[Federal Register Volume 66, Number 14 (Monday, January 22, 2001)]
[Proposed Rules]
[Pages 6768-6829]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-39]
[[Page 6767]]
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Part II
Department of Energy
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Office of Energy Efficiency and Renewable Energy
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10 CFR Part 430
Energy Conservation Programs for Consumer Products; Test Procedures for
Central Air Conditioners and Heat Pumps; Proposed Rule
Federal Register / Vol. 66, No. 14 / Monday, January 22, 2001 /
Proposed Rules
[[Page 6768]]
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DEPARTMENT OF ENERGY
Office of Energy Efficiency and Renewable Energy
10 CFR Part 430
[Docket No. EE-RM/TP-97-440]
RIN 1904-AA46
Energy Conservation Program for Consumer Products: Test
Procedures for Central Air Conditioners and Heat Pumps
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Proposed rule and public hearing.
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SUMMARY: The Department of Energy (DOE) is proposing changes to its
regulations on test procedures for central air conditioners and heat
pumps. Today's revision of the test procedure is not expected to alter
the minimum energy conservation standards currently in effect. The
revised test procedure is up-to-date, more complete and better
organized than the current version. It should yield more accurate
measurements of the energy efficiency of central air conditioners and
heat pumps.
DATES: Comments must be received on or before March 23, 2001. DOE is
requesting a signed original, a computer disk (WordPerfect 8) and 10
copies of the written comments. The Department will also accept e-
mailed comments but you must send a signed original. Oral views, data,
and arguments may be presented at the public workshop (hearing) in
Washington, DC, beginning at 9 a.m. on February 7, 2001.
The Department must receive requests to speak at the workshop and a
copy of your statements no later than 4 p.m., January 9, 2001, and we
request that you provide a computer diskette (WordPerfect 8) of each
statement at that time. The DOE panel will read the statements in
advance of the hearing and requests that speakers limit oral
presentations to a summary. Attendees will have an opportunity to ask
questions.
ADDRESSES: Please submit written comments, and requests to speak at the
public hearing to: Brenda Edwards-Jones, U.S. Department of Energy,
Office of Energy Efficiency and Renewable Energy, Hearings and Dockets,
Test Procedures for Central Air Conditioners Including Heat Pumps,
Docket No. EE-RM-97-440, EE-41, Room 1J-018, Forrestal Building, 1000
Independence Avenue, SW., Washington, DC 20585-0121. You may send email
to: [email protected]. The hearing will be at the U.S.
Department of Energy, Forrestal Building, Room 1E-245, 1000
Independence Avenue, SW., Washington, DC. You can find more information
concerning public participation in this rulemaking proceeding in
section VI, ``Public Comment,'' of this notice.
You may read copies of the transcript of the public hearing and
public comments at the Department of Energy Freedom of Information
Reading Room, U.S. Department of Energy, Forrestal Building, Room 1E-
190, 1000 Independence Avenue, SW., Washington, DC 20585, (202) 586-
3142, between the hours of 9 a.m. and 4 p.m., Monday through Friday,
except Federal holidays.
FOR FURTHER INFORMATION CONTACT:
Michael G. Raymond, U.S. Department of Energy, Energy Efficiency and
Renewable Energy, Mail Station EE-41, Forrestal Building, 1000
Independence Avenue, SW, Washington, DC 20585-0121, (202) 586-9611
Eugene Margolis, Esq., U.S. Department of Energy, Office of General
Counsel, Mail Station GC-72, Forrestal Building, 1000 Independence
Avenue, SW, Washington, DC 20585-0103, (202) 586-9526
SUPPLEMENTARY INFORMATION: The proposed rule incorporates, by
reference, seven test procedures published by the American Society of
Heating, Refrigerating, and Air-Conditioning Engineers, Inc. (ASHRAE),
as follows:
Standard 23-1993, ``Methods of Testing for Rating Positive
Displacement Refrigerant Compressors and Condensing Units.''
Standard 37-1988, ``Methods of Testing for Rating Unitary
Air-Conditioning and Heat Pump Equipment.''
Standard 41.1-1986 (Reaffirmed 1991), ``Standard Method
for Temperature Measurement.''
Standard 41.2-1987 (Reaffirmed 1992), ``Standard Method
for Laboratory Airflow Measurement.''
Standard 41.6-1994, ``Standard Method for Measurement of
Moist Air Properties.''
Standard 41.9-1988, ``A Standard Calorimeter Test Method
for Flow Measurement of a Volatile Refrigerant.''
Standard 116-1995, ``Methods of Testing for Rating for
Seasonal Efficiency of Unitary Air Conditioners and Heat Pumps.''
One test procedure of the American Society of Heating,
Refrigerating, and Air-Conditioning Engineers/Air Moving and
Conditioning Association, Inc. (ASHRAE/AMCA) is incorporated by
reference:
Standard 51-1999, ``Laboratory Methods of Testing Fans for
Rating.''
One test procedure of the Air-Conditioning and Refrigeration
Institute (ARI) is incorporated by reference:
Standard 210/240-1994, ``Unitary Air-Conditioning and Air-
Source Heat Pump Equipment.''
You can view copies of these standards at the Department of
Energy's Freedom of Information Reading Room at the address stated
above. You can also obtain copies of the ASHRAE, ASHRAE/AMCA and ARI
Standards from the American Society of Heating, Refrigerating, and Air-
Conditioning Engineers, Inc., 1971 Tullie Circle, NE, Atlanta, GA
30329, http://www.ashrae.org; and the Air-Conditioning and
Refrigeration Institute, 4301 North Fairfax Drive, Suite 425,
Arlington, VA 22203, http://www.ari.org, respectively.
I. Summary of Proposed Rule
II. Introduction
A. Authority
B. Background
1. Short and Long-term Plans
2. Background for Today's Proposed Rulemaking
III. Discussion of Comments
A. General
1. Non-ducted split system air conditioners and heat pumps
2. Small-duct, high-velocity systems
3. Non-defrost (limited-range) heat pumps
4. Heat pumps that incorporate a heat comfort controller
5. Other commercially-available equipment that should be covered
in the test procedure
B. Definitions
1. Revise definition 1.20 ``Demand-defrost control system''.
C. Testing Conditions
1. Section 2.2.4. Wet-bulb temperature requirements for air
entering the indoor and outdoor coils.
2. Section 2.2.5. Additional refrigerant charging requirements
D. Testing Procedures
1. Section 3.1.4. Indoor air volume rates for a variable-speed,
constant CFM blower.
2. Section 3.1.4.1. Cooling air volume rate.
3. Section 3.1.4.1.1. External static pressure.
4. Sections 3.2.3 and 3.5.3. Testing a two-capacity compressor
system.
5. Section 3.3. Capacity adjustments for barometric effects
6. Sections 3.5.3 and 3.8.1. Cyclic degradation coefficients
E. Calculations of Seasonal Performance Descriptors
1. Sections 4.1.4 and 4.2.4. Variable-speed bin calculations
IV. Summary of Proposed Modifications to the DOE Air Conditioner and
Heat Pump Test Procedure
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A. Update and Add References for ASHRAE and ARI Standards
B. Air Volume Rates
C. Cyclic Testing
D. Fanless (coil-only) Units
E. Frost Accumulation Test
F. Test Tolerance Tables
G. Pretest Intervals
H. Multi-Capacity Systems
I. Triple-split Systems
J. Time-Adaptive Defrost Control Systems
K. Test Unit Installation
L. Test Apparatus and Measurement/Sampling Frequency
M. Different Compressor Speeds and Indoor Fan Capacities Between
Cooling and Heating
N. Secondary Test Requirements
O. HSPF Calculations
V. Procedural Requirements
A. Review Under the National Environmental Policy Act of 1969
B. Regulatory Review
C. Regulatory Flexibility Review
D. ``Takings'' Assessment Review
E. Federalism Review
F. Paperwork Reduction Act Review
G. Review Under Unfunded Mandates Reform Act of 1995
H. Review Under Executive Order 12988, ``Civil Justice Reform''
I. Review Under the Treasury and General Government
Appropriations Act, 1999
J. Plain Language Review
VI. Public Comment Procedures
A. Written Comment Procedures
B. Issues for Public Comment
C. Public Workshop
1. Procedures for Submitting Requests to Speak
2. Conduct of Workshop
I. Summary of Proposed Rule
Today's proposed rule concerns the testing aspect for central air-
conditioners and central air-conditioning heat pumps. The Department
develops these procedures for manufacturers to test products to measure
energy efficiency, energy use, or estimated annual operating cost of a
product. It will interest manufacturers, but consumers of air
conditioners will see no changes due to this revision, which brings the
test procedure up-to-date, and makes it more complete and better
organized. Nearly all the technical content is preserved and the use of
U.S. customary (i.e., inch-pound) units is maintained. Air conditioners
and heat pumps that presently meet the NAECA energy conservation
standards will still meet these standards when rated using the revised
test procedure.
II. Introduction
A. Authority
The Energy Policy and Conservation Act requires the Department of
Energy to establish the Energy Conservation Program for Consumer
Products. This program sets test procedures, energy consumption and
efficiency labeling, and energy conservation standards for many
household, consumer products.\1\ The Act requires DOE to determine to
what extent a proposed test procedure would change the energy
efficiency or energy use of a product from the current test procedure.
If we determine that a new test procedure would change the efficiency
or use of a covered product, we will amend the standard. To determine
the new energy conservation standard, we measure the energy efficiency
or energy use of a representative sample of covered products that
minimally comply with the existing standard. The average efficiency of
these representative samples, tested using the amended test procedure,
constitutes the amended standard. EPCA, Section 323(e)(2).
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\1\ Public Law 94-163, as amended by the National Energy
Conservation Policy Act, Public Law 95-619, the National Appliance
Energy Conservation Act of 1987, Public Law 100-12, the National
Appliance Energy Conservation Amendments of 1988, Public Law 100-
357, and the Energy Policy Act of 1992, Public Law 102-486, Part B
of Title III of Energy Policy and Conservation Act, as amended, is
referred to in this proposed rule as ``EPCA'' or the ``Act.'' Part B
of Title III is codified at 42 U.S.C. 6291-6309.
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B. Background
1. Short and Long-Term Plans
This proposed DOE test procedure is the first step of a planned
two-step revision process. The immediate goal is to promulgate a
revised test procedure that is up-to-date, more complete and better
organized. Nearly all the technical content is preserved and the use of
U.S. customary (i.e., inch-pound) units is maintained. One especially
important goal of this first step is to have air conditioners and heat
pumps that presently meet the NAECA energy conservation standards to
still meet these standards when rated using the revised test procedure.
The second step in the planned revision process is to convert the
DOE test procedure to using Systeme Internationale (SI) units while
maximizing compatibility with pertinent standards of the International
Organization for Standardization (ISO). The goal of this second step is
a DOE metric test procedure which will also meet the requirements
specified by ISO for determining capacities, EER(s) for a ``moderate''
climate, and COP's. For example, DOE plans to directly reference
selected ISO indoor and outdoor test conditions. However, the DOE test
procedure will impose additional requirements, not found in the ISO
test standards, that allow determination of the seasonal performance
factors SEER and HSPF. Presently, the pertinent ISO standards are
either under revision or are being newly developed so we can not yet
fully determine the extent of compatibility between the DOE and ISO
testing and rating procedures. DOE, via NIST personnel, is
participating in the development of the ISO test standards in an effort
to minimize the differences. A proposed DOE metric test procedure will
be available for industry review several months after the revision of
ISO standards (5151 and 13253 or, possibly a combined standard) is
completed.
This two-step test procedure revision will not delay the concurrent
revision of the NAECA energy conservation standards, nor will standards
revision be delayed because of the planned conversion of the test
procedure to SI units. Until a DOE metric test procedure has been
promulgated, you will make predictions of seasonal performance using
the I-P version of the DOE test procedure, i.e., this revision. This
revised test procedure modifies tests for certain configurations, but
is not expected to impact the performance measurements. In the coming
years, when a DOE metric test procedure is progressing through the
rulemaking process, DOE and stakeholders will review the best time line
for implementing the metric test procedure and instituting compatible
NAECA energy conservation standards. As far as possible, the metric
test procedure will retain the current energy efficiency descriptors,
SEER and HSPF.
2. Background for Today's Proposed Rulemaking
The first DOE test procedure covering central air conditioners and
heat pumps was published in the Federal Register on December 27, 1979,
and became effective January 17, 1980. 44 FR 76700. The test procedure
was modified once, in March 1988. 53 FR 8304 (March 14, 1988).
Revisions made in 1988 included expanding coverage to variable-speed
air conditioners and heat pumps, addressing split-type non-ducted
units, and modifying the method used for crediting heat pumps that
provide a demand defrost capability.
Five waivers to the DOE test procedure covering central air
conditioners and heat pumps have been granted since the 1988 final
rulemaking. Waivers have been granted to two different brands of non-
defrost heat pumps, to two brands of combined heat pump-water heating
appliances, and for a line of burner-assisted heat pumps. Non-defrost
heat pumps do not contain a defrost controller and are designed to shut
the compressor off under operating
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conditions where frost accumulation on the outdoor coil is likely.
Combined appliances use an extra condensing coil to permit the unit to
provide domestic water heating in addition to space conditioning.
Burner-assisted heat pumps use a gas-fired burner in the outdoor coil
while using electricity to power the refrigerant compressor.
In revising this test procedure, we considered whether actions
could be taken to eliminate the continued need for any of the granted
waivers. Today's proposed rule covers testing and calculation of HSPF
for non-defrost, all-electric heat pumps, eliminating the first two of
the five waivers discussed in the preceding paragraph. As the market
for dual fuel heat pumps, including burner assisted heat pumps, and
combined heat pump-water heating appliances grows, we will pursue the
development of separate test procedures for these devices, which will
eliminate the remaining three waivers.
We completed the first draft of this revised test procedure for
central air conditioners and heat pumps in June 1996. The draft test
procedure addressed equipment features presently not covered and
improved upon the completeness and readability of the document. The
June 1996 draft test procedure was distributed to members of the HVAC
industry and academia for comment on the proposed changes.
Several parties provided comments on the June 1996 draft test
procedures. We determined that more input on several issues would be
beneficial, and DOE held a workshop on September 25, 1997. The workshop
focused on five areas of concern. The first area was the identification
of commercially-available equipment that is not adequately addressed in
the existing test procedure. Examples include non-defrost heat pumps,
heat pumps that incorporate a heat comfort controller, multi-split non-
ducted heat pumps, two-capacity heat pumps that are sized to meet the
space cooling load while operating at low capacity, small duct systems,
and single-speed heat pumps having a variable-speed indoor fan that is
modulated based on outdoor temperature. The second issue was the
appropriate way to conduct steady-state and cyclic testing on units
having a variable-speed, constant-air-volume-rate indoor blower. The
third area of concern dealt with appropriate adjustments in order to
credit a demand defrost capability and to account for the effect of
barometric pressure. A group of items that pertained to specifics on
lab testing procedures composed the fourth topic of discussion.
Examples included how to best test packaged units having leakage,
whether to limit manufacturer-specified special lab set-up
requirements, recommended static pressure tap manifolding, and
electrical energy measurement requirements. The fifth issue concerned
the development of new defaults for the cyclic degradation
coefficients, as an alternative to having to conduct tests to determine
the coefficients.
A transcript of the discussions at the September 25 workshop is
available for review in the DOE Freedom of Information Reading Room.
The section below summarizes comments received throughout the revision
process. During the workshop, several items were introduced but left
unresolved. In many of these cases, ARI industry members indicated that
they would offer more input and, where possible, a consensus response
in the months following the workshop.
At the invitation of ARI, NIST participated in a meeting and
teleconferences hosted by the ARI Unitary Small Equipment Engineering
Committee in September and October of 1997 and February of 1998. For
the meetings/teleconferences that followed the September 25, 1997
Workshop, discussions on DOE test procedure issues focused mainly on
eleven issues, namely: (1) Small duct systems, (2) non-defrost systems,
(3) multiple split heat pumps, (4) variable-speed, constant CFM
blowers, (5) heat pumps that incorporate a heat comfort controller, (6)
two capacity heat pumps that are sized to meet the design cooling load
while operating at low speed, (7) definition for a demand defrost
system, (8) effects of barometric pressure, (9) testing of packaged
systems with internal leaks, (10) special laboratory setups, and (11)
new default values for the cyclic degradation coefficients,
CD (the measure of performance degradation from cycling
losses). Written comments were received dated 24 November 1997 from ARI
(ARI, No. 6) that addressed these particular areas. ARI formed a task
group to provide additional input on three items: #4, #6, and #9. ARI
also hoped to provide data and a strawman approach for addressing item
#11. These last four items were discussed during a February 1998
teleconference but ARI provided no consensus by the end of February,
the cutoff date imposed by DOE.
The 24 November 1997 written comments from ARI are included among
the overall comment summary provided below. With regard to unresolved
issues associated with ARI items #4, #6, and #9, we implemented changes
based on the information gathered to date. Today's rulemaking proposes
no changes for the CD defaults that may be used instead of
conducting extra tests. DOE is willing to investigate and consider new
CD defaults based on the hardware features of the air
conditioner or heat pump. ARI and its members have thus far provided no
test data nor made any recommendations concerning the hardware features
(e.g., type of expansion device, with or without a time delay relay on
the indoor fan, type of compressor, off-cycle power consumption,
refrigerant charge quantity, rated capacity, etc.) that should be
included in a statistical analysis to identify the primary factors and
the associated correlations.
A draft of this proposed test procedure was posted to the Office of
Codes and Standards web site in October 1998. This document was revised
during the summer of 1999 to comply with the President's Memorandum of
June 1, 1998, ``Plain Language in Government Writing.'' Thereafter,
some sections of the proposed test procedure were reorganized and
amended in response to comments received during the DOE internal review
process.
In the proposed central air conditioner and heat pump standards
rule (65 FR 59590, October 5, 2000), the Department discussed issues
associated with mandating thermostatic expansion valves, or TXVs, to
help maintain equipment performance under improper charge or airflow.
In the standards final rule, we decided not to adopt a TXV requirement,
but considered pursuing modifications to this test procedure to
encourage the use of TXVs. Such modifications will not be part of this
rulemaking, but will be considered in a separate process. Related
issues that may be discussed in the separate process include the
alternate rating method for mixed systems. The alternate rating method
is not a part of this revision, which concerns only appendix M to
subpart B of 10 CFR part 430. The alternate rating method is discussed
in 10 CFR Sec. 430.24(m). In the last revision of this test procedure
in 1988, the adoption of a standard rating procedure for untested
combinations of split systems was proposed, but the Department decided
not to include a standard rating procedure in the test procedure rule.
Instead, the Department requested the National Bureau of Standards to
develop a rating method available to any manufacturer to use in rating
untested combinations. Manufacturers may use this method or any other
after obtaining the Department's approval. It may again be time to
discuss a standard mixed system rating method included in the test
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procedure. These issues will be discussed in a workshop to be held in
the spring of 2001.
III. Discussion of Comments
Following the September 1997 workshop, we received comments from
the ARI Unitary Small Equipment Engineering Committee and individual
ARI members, Proctor Engineering Group, and from the Florida Solar
Energy Center. We grouped these comments into the following categories
corresponding to sections of the test procedure: General, Definitions,
Testing Conditions, and Testing Procedures. (ARI, No. 6, PEG, No. 3,
FSEC, No. 7)
A. General
1. Non-ducted Split System Air Conditioners and Heat Pumps
Non-ducted units may use one or more indoor coils. When two or more
indoor coils are used, they may operate in response to a single or
multiple room thermostats. Standards of the International Organization
for Standardization (ISO) differentiate non-ducted units as single or
multiple room thermostat systems. We refer to equipment having one or
more indoor coils all controlled by a single indoor thermostat as mini-
split systems. We refer to equipment that uses two or more indoor
thermostats to regulate the operation of two or more indoor coils as
multi-split systems.
The current DOE test procedure does not differentiate between mini-
split and multi-split systems. Both are tested and seasonal
calculations are based on all indoor coils operating simultaneously.
The zoning capability of multi-split units, though not operating some
indoor coils, is not credited.
As part of its 1992 waiver petition, EnviroMaster International
(EMI) sought ``to test its three and four zone MC/MH series systems in
the manner prescribed in the DOE test for two zone systems.'' 57 FR
53736 (November 12, 1992). The modification noted in the Decision and
Order was to change the wording of Section 3.1.7 to the following:
``Subsystems of multizone split-type ductless systems shall be
tested as a single system. The system energy efficiency shall be
based on the sum of the measured capacities of all of the zones in
the system divided by the total input power used by the subsystems
compressors, outdoor fans, indoor air handlers, and any additional
power used by the system.''
ARI commented on this issue: ``Our members do not believe any
change is necessary to the test procedures to address multiple split
heat pumps. We are unaware of any unfair treatment of this product in
the industry by the current test methods.'' (ARI, No. 6 at 1).
We propose no changes in today's test procedure. The option of
testing each zone separately is possible. Such extra testing should
provide a more complete description of the unit's capabilities.
However, the benefits would have to be weighed against the considerable
increase in the testing burden. The Department recommends tabling this
issue until a multi-split manufacturer deems that a different and, most
likely, more burdensome test approach is needed.
2. Small-duct, High-velocity Systems
Unico originally requested that DOE add a new class (or subclass)
of central air conditioners and heat pumps that covered small-duct,
high-velocity (SDHV) systems. Unico recommended changes to the test
procedure that were coupled with DOE issuing separate NAECA standards
for SDHV systems. The main test procedure changes were to impose higher
minimum external static pressures and lower maximum air volume rates
requirements on SDHV systems. Unico also provided a proposed definition
for SDHV systems. (Unico, No. 5 at 2).
Unico noted how small duct systems differ from more conventional
systems: external static is typically 1.5 inches of water, air volume
rate is usually one-half of a conventional system, duct outlets into
the room are typically two inches in diameter, and air velocity
entering the room is in the 800 to 2000 feet per minute range. ``We
feel this product is different enough that it * * * should be
considered for a different class. We have different classes for room
air conditioners; we have different classes for packaged terminal units
and ductless systems versus ducted systems.'' (Unico, No. 2HH at 42).
ARI commented: ``ARI believes that no changes to the existing test
procedure are necessary for these products. They are currently tested
and rated in accordance with the existing procedure. Furthermore, ARI
does not believe a different product class or category should be
created for small-duct systems, since that would allow for a
potentially separate efficiency standard. They should be held to the
same minimum efficiency standards as conventional systems. There is
concern that a separate product class could open a loophole in the
regulations. Other products might be specifically designed to meet the
criteria of the new class, with the only intention being that they
would be subjected to a less stringent efficiency standard, while still
used in applications for typical equipment.'' (ARI, No. 6 at 1).
Unico later submitted an alternative proposal to DOE. In its
alternative proposal, Unico plans to exercise the option of testing its
line of SDHV units as coil-only units. In the Unico product line, the
blower assembly is sold separately from the indoor coil assembly. The
only change in the test procedure needed to implement this alternative
approach is to relax the maximum pressure drop allowed when testing
coil-only units. Presently, the test procedure states that the pressure
drop across the indoor coil assembly must not exceed 0.30 inches of
water. Unico requested that the limit be increased, preferably to 0.50
inches of water.
Today's proposed test procedure sets a higher pressure drop limit
of 0.5 inches of water when testing coil-only units that meet the
definition of a small-duct, high-velocity system. The proposed
definition is given in section 1.46. We welcome comments on this
action. Possible points for consideration include whether the action is
acceptable as proposed or if incorporated in combination with a
different default fan power and heat adjustment.
3. Non-defrost (Limited-range) Heat Pumps
We granted the first of two waivers for non-defrost heat pumps to
Airlex in 1988. 53 FR 52216 (December 27, 1988). The waiver called for
testing at 47 deg.F and 62 deg.F in lieu of testing at 35 deg.F and
17 deg.F. HSPF was calculated. Airlex, to the knowledge of DOE, has
since gone out of business. We granted the second waiver to EMI in
November 1992. 57 FR 53736 (November 12, 1992). Unlike Airlex, EMI did
not seek to report HSPF and so did not offer proposed modifications to
the DOE test procedure. We required that EMI state in its printed
materials on its non-defrost products that ``no HSPF value has been
measured since the heat pump cannot be operated at temperatures below
35 deg.F.''
At this time, non-defrost heat pumps appear to be limited to non-
ducted, multi-zone, multi-split heat pumps having multiple
refrigeration systems where one refrigeration system may be heating
while another is cooling. In such systems, having one refrigeration
system conduct a defrost while the other refrigeration system(s) is
cooling is apparently quite difficult (see below EMI comment). No
opposition was voiced at the workshop to a DOE proposal to cover non-
defrost heat pumps in the test procedure. We also
[[Page 6772]]
received the following comments at the workshop:
In response to the question on why EMI can not make its non-ducted,
multi-refrigeration system, multi-split heat pumps defrost, EMI stated
``we have put preliminary designs together, but we've never been able
to successfully control the defrost cycle while operating all the
circuits.'' (EMI, No. 2HH at 23). Trane spoke against the option of
creating a new class and a new NAECA HSPF energy standard for non-
defrost heat pumps. (Trane, No. 2HH at 24). An ARI representative said
that presently a multi-zone multi-split would be tested with all
refrigeration systems operating in the same mode. (ARI, No. 2HH at 23).
In written comments received following the workshop, ARI stated: ``For
the same rationale as with small duct systems, ARI does not believe a
separate product class or category is needed for non-defrost heat
pumps. We also recommend no change in the current test procedure to
accommodate non-defrost systems. As discussed above, they should be
held to the same minimum efficiency standards as conventional
systems.'' (ARI, No. 6 at 1).
Since the workshop, DOE received information on non-ducted, multi-
refrigeration system, multi-split heat pumps made by two manufacturers
other than EMI. Both of these competing multi-split products provide a
defrost capability. The key differentiating feature is that these units
do not provide the option of simultaneous heating and cooling like the
EMI product. EMI apparently values this simultaneous cooling/heating
capability more than a defrost capability while these other two
manufacturers do without the simultaneous mode feature in return for
being able to defrost. To date, we have found no product that provides
both the simultaneous heating/cooling feature and a reverse defrost
cycle capability.
From a test procedure standpoint, several options are available.
One option, in line with ARI's comment, is to make no applicable
changes to the test procedure and allow the existing EMI (and Airlex)
waivers to remain. This option defers the issue until we receive
another waiver request for a non-defrost heat pump. A second option is
to make additions to the test procedure so that the HSPF of any type of
non-defrost heat pump could be evaluated. A third option is to exclude
heat pumps that are designed to simultaneously heat and cool ``whether
they can defrost or not'' from the scope of the test procedure. The
rationale for exclusion would be that such units generally compete with
commercial applications where packaged terminal heat pumps and air
conditioners are used and so should be tested and rated in a manner
comparable to the approach used for packaged terminal equipment (i.e.,
heating performance descriptor becomes COP at 47 deg.F and the
equipment has no HSPF rating). For this third option, the test
procedure could either be changed to cover all other non-defrost heat
pumps (even though DOE knows of only the EMI simultaneously heat and
cool, non-defrost heat pump) or no changes could be made, again
deferring until we receive another waiver petition.
DOE requests comment on the above three and any other options for
handling non-defrost heat pumps. To provide an understanding of the
test procedure changes required to cover non-defrost heat pumps, we
include in today's proposed test procedure (see Sections 3.6.1.1 and
4.2.1.1) the steps required to test and rate most conceivable types of
single-speed, non-defrost heat pumps.
4. Heat Pumps That Incorporate a Heat Comfort Controller
Heat comfort controllers modulate the operation of the resistive
elements of a heat pump to minimize temperature swings of the heated
supply air when operating below the heat pump's balance point.
Frequently, they seek to maintain a minimum delivery temperature when
operating above the balance point. This latter application can cause
the system to use more electrical energy than the heat pump alone would
use to meet the building load.
At the 25 September 1997 DOE workshop, the issue was discussed at
some length. The workshop members noted that the item can be both an
OEM product that is an integral part of the as-shipped heat pump or it
can be a field added accessory that is provided by the heat pump
manufacturer or, more commonly, by a third party supplier. Also,
assuming that the test procedure was modified to cover heat pumps with
a heat comfort controller, no workshop invitee spoke in favor of new
and separate NAECA standards for such products. The following points
were also made at the workshop:
ARI stated if the manufacturer incorporates a heat comfort
controller as an OEM feature, it should be covered by the test
procedure. (ARI, No. 2HH at 31). Trane stated if the test procedure
is modified to cover heat comfort controllers, the rating should be
based on operating the controller at its maximum delivery
temperature. (Trane, No. 2HH at 60). Proctor Engineering commented:
``Units designed to operate with strip heat above the balance
temperature should not receive any special consideration in the test
process or the [NAECA] Standard. Allowing special consideration will
open the door to lower efficiencies in the field where installation
errors already result in excessive strip heat use.'' (PEG, No. 3 at
3). ARI commented: ``We request DOE to develop a rating procedure
for heat pumps that incorporate the use of electric resistance heat
above the balance point. The procedure should be based on the
highest indoor air delivery/supply temperature setting that the
control system allows, so that the most conservative rating will be
derived. Any heat pump that uses this feature, and still meets the
minimum HSPF standard should be permitted. However, the existing ICC
Model Energy Code prohibits such systems, because there is no rating
method for them.'' (ARI, No. 6 at 2).
Today's proposed test procedure covers heat comfort controllers as
applied to most types of single-speed heat pumps. With the heat comfort
controller disabled, conduct all the same heating mode tests. Following
the normally conducted heating mode test at 47 deg.F outdoor
temperature, conduct an extra abbreviated test with the controller
enabled to determine the air delivery temperature when the controller
is set to its maximum setting (see Section 3.1.9). We describe proposed
steps for calculating the HSPF of a single-speed heat pump having a
heat comfort controller in Section 4.2.1.2.
5. Other Commercially-available Equipment that Should Be Covered in the
Test Procedure
One focus of the 25 September 1997 DOE workshop was to identify
commercially-available equipment that is not covered by the DOE test
procedure. For the majority of equipment discussed at the workshop, we
provide separate discussions elsewhere in this summary. Equipment types
that were discussed and thought not to be a commercial product
included: (1) Triple-capacity heat pumps and (2) units that use a two-
capacity (two-stage) compressor and a variable-speed indoor fan that is
modulated at each fixed stage of compressor operation.
B. Definitions
1. Revise Definition 1.20 ``Demand-defrost Control System''
ARI commented: ``We recommend that DOE expand the current ARI
Standard 210/240 definition of a demand defrost system to include
sampling intervals of a minimum of 10 minutes and not to have the
definition pertain to time adaptive systems.'' (ARI, No. 6 at 2)
DOE's goal is to improve upon the existing definition provided in
ARI Standard 210/240-94, Section A1.11, and in particular, to stop
allowance of
[[Page 6773]]
the (maximum) 3 percent HSPF credit to units that truly do not offer a
demand defrost capability. We provide a proposed definition for a
``demand-defrost control system'' that seeks to be consistent with
ARI's comment as Definition 1.20.
C. Testing Conditions
1. Section 2.2.4. Wet-bulb Temperature Requirements for Air Entering
the Indoor and Outdoor Coils
ARI commented: ``In order to provide better repeatability when
testing packaged systems, which may be susceptible to internal air
leakage, ARI believes it may be necessary to specify an outdoor dew
point temperature when units are located in the outdoor chamber
(ambient). A task group has been formed to investigate this issue and
we will provide our recommendations to DOE as soon as they are
available.'' (ARI, No. 6 at 2).
DOE's understanding of the impact of a leak that could result in
optimistic results is as follows:
(1) Leak of outdoor air to a location upstream of the indoor coil
but downstream of the test facility inlet wet bulb temperature (dew
point, relative humidity) sensor. If the outdoor dew point is lower
than the indoor dew point, the measured latent capacity will be higher
than the true latent capacity, while the measured sensible capacity
will be lower than the actual sensible capacity. The effect on total
capacity will depend on dry bulb temperature of the outdoor air (82
deg.F or 95 deg.F) and the depression of the outdoor dew point
relative to the indoor dew point.
(2) Leak of outdoor air to a location downstream of the indoor
coil. Results are the same as (1) except that the depression of the
outdoor dew point would have to be greater to overcome the negative
effect on sensible capacity. The measured air volume rate on the indoor
side would be higher than the actual rate at the coil and would thus
increase the perceived sensible and latent capacity.
DOE's understanding of the other factors that are related to this
issue are as follows. First, psychometric rooms have difficulty
achieving and maintaining outdoor wet bulb temperatures in the mid 70's
deg.F and higher during the A and B Tests. If the internal leakage is
significant, obtaining a 6 percent energy balance would be difficult to
achieve. Although potentially frustrating for a third party tester, the
lack of an energy balance should provide impetus for the manufacturer
to reduce the leakage. You can avoid the difficulty in maintaining the
outdoor wet bulb temperature during the C and D dry coil tests by
meeting the requirements of achieving a dry indoor coil, and by using
the equation for determining sensible cooling capacity, as opposed to
total cooling capacity.
In an effort to avoid potential cases where the leakage causes an
optimistic result while still providing an energy balance of 6 percent
or less, DOE recommends operating at an outdoor dew point temperature
that is the same as the indoor dew point temperature during wet-coil
tests where the unit does not reject condensate to the outdoor coil.
DOE proposes a test tolerance of 3.0 deg.F in the
agreement of the average outdoor dew point temperature with the average
indoor dew point temperature. In nominal terms, the target outdoor wet
bulb temperatures will be 71.7 deg.F and 67.7 deg.F for the A and B
Tests, respectively.
During heating mode tests, leaks could cause problems if the
Outdoor Air Enthalpy Method is used to provide a secondary check of
capacity. The proposed test procedure includes a recommendation for
regulating the indoor side wet bulb temperature in an effort to
minimize the difference between the indoor and outdoor-side dew point
temperatures.
2. Section 2.2.5. Additional Refrigerant Charging Requirements
ARI stated: ``We believe the test procedure, as currently written,
reasonably addresses the issue of special laboratory setups when
conducting tests, as prescribed in manufacturer's installation
instructions. Therefore, we do not recommend any change with respect to
this issue.'' (ARI, No. 6 at 3).
Presently, any installation step is acceptable so long as it is
specified in the manufacturer's installation instructions, including
remarks that only apply if conducting laboratory testing. As discussed
at the 25 September 1997 DOE workshop, the difficult issue is where to
draw the line. Some special setups are justified and/or required when
lab testing. DOE is only excluding special lab set-ups for refrigerant
charging. With assistance from ARI and third-party laboratories, DOE
will monitor test setup requirements to determine if manufacturers are
specifying installation instructions inconsistent with the majority of
lab installations or otherwise contrary to field practices.
Furthermore, DOE is seeking assistance in establishing installation
guidelines for items such as pre-washing of coils (e.g., what cleaning
agent to use, basic steps that specify the extent of the cleaning),
run-in times on compressors, conditions where components (e.g.,
crankcase heaters) are or are not electrically connected, exclusion of
lab-only (or 25 feet only) lineset specifications, etc. These
guidelines will be incorporated into future revisions of the test
procedure to assist in obtaining consistency in the testing.
In today's proposed test procedure, the title of Section 2.2.5
changes from ``Exclusion of special setup requirements if stated in the
manufacturer published installation manual'' to ``Additional
refrigerant charging requirements.'' The section is included for two
reasons. The first is to disallow the specification of two refrigerant
charging criteria, one that applies for lab testing and one that
applies for a field installation. The fact that a lab setting provides
better quality control is not sufficient for permitting lab testing
using a different charging criteria. The second reason for today's
Section 2.2.5 is to avoid discrepancies and delays when third party
testing is conducted. The third party testing facility should not have
to consult with the manufacturer as to how the unit is to be charged.
In the case of a certification failure, the issue of whether the
testing facility charged the unit correctly should only be based on
whether the manufacturer's charging criteria, as specified in the
unit's installation instructions, were followed.
D. Testing Procedures
1. Section 3.1.4. Indoor Air Volume Rates for a Variable-Speed,
Constant CFM Blower
ARI stated: ``ARI is aware of the need to consider more explicit
procedures for testing units with variable speed blowers. Therefore, we
have organized a task group to develop a prescribed test method for
testing units with variable speed blowers, and we will pass our
recommendations on to DOE as soon as they are available.'' (ARI, No. 6
at 1)
Today's proposed test procedure contains several changes from the
existing test procedure to address testing of units having a variable-
speed, constant CFM blower. For all tests, the exhaust fan of the air
flow measuring apparatus is regulated to obtain an external static
pressure that is as close to, while not being less than, the minimum
external static pressure specified in the test procedure (see
3.1.4.1.1(b), 3.1.4.4.1, 3.1.4.4.2 and 3.1.4.4.3(b)). (The air flow
measuring apparatus, by comparison, is not regulated to obtain the
specified air volume rate, as is done when testing units having other
than a constant-air-
[[Page 6774]]
volume-rate indoor fan.) For some units, one or more tests may have to
be conducted at an external static pressure that is higher than the
required minimum value because of instability problems encountered when
trying to reduce the external static pressure to the specified minimum.
In such cases, steps are outlined for correcting the test results if
the difference between the as-tested and the specified minimum external
static pressure is 0.03 inches of water or more. An example of the
proposed correction method is provided in the last paragraph of
Sections 3.3 and 3.7. For systems that operate at multiple air volume
rates, the fan laws are used to approximate the target external static
pressure for tests conducted at other than the air volume rate used
during the A2 and/or H12 test.
The proposed test procedure includes a check of the agreement
between the lab-measured and manufacturer-certified air volume rates.
Today's proposed test procedure calls for the two values to agree
within 8 percent (see 3.1.4.1.1(b), 3.1.4.2, 3.1.4.4.2, and
3.1.4.4.3(b)). This percentage is proposed based on manufacturer's
comments on the variability of the variable-speed motors relative to
estimates of the impact on rated performance caused by an 8 percent
deviation. Using the heat pump computer modeling program HPSIM, DOE
finds that an 8 percent deviation in SCFM is expected to have a
negligible impact on both capacity and EER at the B Test condition
while still keeping the maximum impact on capacity at the A Test
condition in the 2 percent range. DOE asks that manufacturers provide
feedback on the proposed 8 percent tolerance as well as findings from
lab testing and computer modeling on the impact on capacity and EER of
airflow changes in the 5 to 10 percent range.
Cyclic tests on units having a constant CFM blower may be conducted
with or without the indoor fan enabled. If the cyclic test is conducted
with the blower disabled, steps for correcting for the power draw of
the blower are specified (see 3.5 and 3.5.1).
2. Section 3.1.4.1. Cooling Air Volume Rate
This issue is of interest to the ISO working group that is revising
its air conditioner and heat pump test standards. The adoption of a
maximum air flow limit has thus far been opposed by the majority of the
ISO working group member countries. The following comments were made at
the DOE workshop. A Trane representative noted that the 37.5 SCFM per
1000 Btu/h (450 SCFM per ton) maximum air flow requirement is long-
standing and is of value because it (1) sets a de facto maximum
sensible heat ratio and (2) keeps the air flow in a range that avoids
water being blown off the wetted evaporator. (Trane, No. 2HH at 193). A
representative of York International suggested reevaluating the basis
for the 37.5 SCFM per 1000 Btu/h maximum while considering both full
load and part load capacity conditions. (York, No. 2HH at 197).
For today's proposed revision, no change is made in the maximum air
volume rate limit. DOE sees such a limit as providing a hedge against
promoting efficiency gain at the expense of compromised latent
capacity, especially for coil-only units. The limit also helps in
having the A and B Tests conducted with a fully wetted coil that, in
turn, makes the capacity fluctuations less and the collection of 30
minutes of steady-state data more readily obtainable. DOE encourages
and would participate in investigations on whether this limit should be
other than its present value of 37.5 SCFM per 1000 Btu/h, or whether an
alternative mechanism, such as a limit on sensible heat ratio, should
be considered.
Discussion of this issue is timely because no such maximum air
volume limit is presently included in ISO Standards 13253 and 5151 for
ducted and non-ducted air conditioners and heat pumps. A U.S. proposal
to adopt the metric-equivalent of the 37.5 SCFM per 1000 Btu/h limit
was voted down by the ISO working group that is presently revising ISO
Standards 5151 and 13253. The vast majority of other member countries
on the working group perceive air volume rate as a design parameter
that should not be impacted by a rating standard. The ISO standards
provide capacity test conditions that correspond to a hot, dry climate
where latent capacity is not a concern. ISO also provides capacity test
conditions for a cool climate. ISO working group members from countries
that will rate at this cool climate condition argue that high air
volume rates are needed in order to assure that the air delivery
temperature is not objectionably cool. Finally, with the exception of
the U.S., most countries represented on the ISO working group are
predominantly concerned with non-ducted products and calorimeter
testing where indoor air volume rate is not typically measured.
The goal when converting the DOE test procedure to a metric format
is to make it ISO compatible. Most ducted units sold in the U.S. today
are rated at an air volume rate that is less than the 37.5 SCFM per
1000 Btu/h upper limit. This fact suggests that maximum efficiency is
achieved at air volume rates lower than 37.5 SCFM per 1000 Btu/h. Thus,
having a upper limit may not be important enough to warrant a deviation
from ISO. Either way, now is the time to discuss this issue since the
revision of the ISO Standard 13253 is still underway. However, it seems
unlikely that ISO will adopt an upper limit on air volume rate.
3. Section 3.1.4.1.1. External Static Pressure
Proctor Engineering Group recommended the following changes to make
the test specification conform better to measurements of installed
systems. When testing units having an indoor fan, ``the minimum static
pressure should be revised to:
0.50 inches of water column for all systems, or
The maximum allowable external static pressure specified
by the manufacturer, whichever is less.''
When rating fanless units, ``the default Btu/hr (watt draw of the
indoor fan motor) should be revised to 2000 Btu/hr per 1000 cfm (586
Watts per 1000 cfm).'' For comparison, the external static pressure and
fan heat/power defaults presently used in the existing DOE test
procedure are 0.1, 0.15, and 0.2 inches of water, with the assigned
value being a function of the unit's rated capacity. The presently
referenced fan heat/power default adjustment is 1250 Btu/h per 1000
SCFM (365 Watts per 1000 SCFM). Proctor Engineering Group supported its
proposed changes by providing results from field measurements on 28 new
systems in new construction in Phoenix, Arizona. (PEG, No. 3 at 3).
The Florida Solar Energy Center sent a report on field monitoring
work which indicated that ``the standard assumption of an external
static pressure of 0.2 inches of water column (IWC) for the air handler
fan was far lower than the typical values encountered in the field. The
average we measured in 14 evaluated installations was 0.54 IWC (range
was 0.27 to 0.91 IWC).'' The commenter goes on to state his strong
belief that ``the ARI test condition should be modified to 0.5 IWC to
better reflect the actual performance that will be achieved by the air
conditioners operating under realistic conditions. Because of this
change, the watt draw of the fan motor (and heat released into the
supply air stream) should also be revised to reflect the increase in
fan power from this change.'' (FSEC, No. 7 at 1)
Because of concern that such changes would impact the SEER and HSPF
of units that have ratings at or near the
[[Page 6775]]
NAECA minimum standard levels, DOE does not plan to change the static
pressure requirements in this revision of the test procedure. Instead,
DOE will continue dialogue with the working group that is revising ISO
Standard 13253. When the revision of ISO 13253 is completed, DOE will
determine the suitability of incorporating part or all of this test
procedure in the DOE metric test procedure. ISO Standard 13253 is
presently under revision with the present draft containing the
following requirements for the minimum external static requirements.
(The Inch-Pound equivalent values are not part of the proposed 13253
table but are included here to aid the reader.)
------------------------------------------------------------------------
Minimum static pressures
-------------------------------------------------------------------------
Minimum external static
Standard capacity ratings (kW) [kBtu/h] pressure (Pa) [inches of
H2O]
------------------------------------------------------------------------
0 to 8 [0 to 27.3]....................... 25 [0.10]
8 to 12 [27.3 to 41.0]................... 37 [0.15]
12 to 20 [41.0 to 68.3].................. 50 [0.20]
20 to 30 [68.3 to 102.4]................. 62 [0.25]
30 to 45 [102.4 to 153.6]................ 75 [0.30]
45 to 82 [153.6 to 279.9]................ 100 [0.40]
82 to 117 [279.9 to 399.3]............... 125 [0.50]
117 to 147 [399.3 to 501.7].............. 150 [0.60]
[Above 147 Above 501.7].................. 175 [0.70]
------------------------------------------------------------------------
The numbers up to 20 kW are consistent with the values presently
cited in the existing and in this proposed revision of the DOE test
procedure.
As for fanless units, the draft revision of ISO 13253 contains a
thermodynamically-based equation (volume flow rate x total pressure
drop divided by fan static efficiency x fan motor efficiency) to
estimate default fan heat/power adjustments. Total pressure drop is
taken as the sum of the following:
(1) The lab-measured pressure drop across the indoor, fanless unit
(2) The applicable minimum external static pressure listed in the
above table
(3) An estimate for the pressure drop across a typical blower
cabinet (=50 Pa).
The minimum external static pressure requirements thus impact both
the rating for fanless and blower coil units. For residential size
equipment, ISO Standard 13253R uses the following empirical fits to
determine the fan static (SE) and fan motor efficiencies (MEr).
SE=0.1881*Ln(Pe + Pc + 50) - 0.4700
MEr=0.060*Ln[Q*(Pe+Pc + 50) /SE]+0.123
Where Q is the measured air volume rate of standard air (m3/
s), Pe is the minimum external static pressure (Pa), and
Pc is the internal static pressure drop of the indoor coil
cabinet assembly measured during the cooling capacity test (Pa).
Any proposal to raise the minimum external static pressure
requirements and possibly tweak the ISO approach for estimating fan
heat/power adjustments will first have to be agreed upon by the U.S.
delegates on the ISO working group. If the proposal is endorsed by the
U.S. delegation, then the delegation must submit the proposed change
for the consideration of the full working group. NIST, as a member of
the U.S. delegation, has raised the issue for discussion among the U.S.
delegation. At this point, the U.S. delegation does not have plans for
recommending changes to ISO 13253 in this area.
4. Sections 3.2.3 and 3.6.3. Testing a Two-capacity Compressor System
ARI stated: ``ARI agrees with DOE that the test procedure should be
modified to accommodate more appropriate testing of multiple capacity
heat pumps that are sized to meet the cooling load at fan speeds lower
than the maximum. We have established a task group to investigate this
issue, and will provide our recommendations to DOE as soon as they are
available.'' (ARI, No. 6 at 2).
The proposed test procedure covers two-capacity heat pumps that are
designed to operate exclusively at low capacity in meeting the space
cooling load while using both low and high capacities when space
heating. SEER of the unit is evaluated in the same way as specified for
a single-speed air conditioner. HSPF is evaluated using the same
algorithm as specified for a ``normal'' two-capacity heat pump except
that the building loads for the heating temperature bins are based on
the heat pump's heating capacity when tested at low capacity and 47
deg.F outdoor dry bulb temperature. Previously, the building loads were
tied to the heat pump's heating capacity at 47 deg.F and high
compressor capacity. The change will drive the balance point of the
heat pump down. The issue on this particular subject is whether the
heat pump must have a lockout feature to prevent cooling at high
capacity or is it sufficient that the rating is applicable so long as
the heat pump is sized to operate at low capacity at design cooling
conditions? The advantages of the lockout would be to (better) assure
that high compressor capacity would not be used when cooling and a
particular unit would only have one unique NAECA-required SEER and HSPF
rating. Without the lockout feature, the unit would have two SEER and
HSPF ratings. A lockout feature is required in accordance with today's
proposed test procedure but DOE welcomes further discussion on this
issue.
5. Section 3.3. Capacity Adjustments for Barometric Effects
ARI commented: ``ARI is aware that barometric pressure can have an
affect on test results. However, we believe DOE should allow ASHRAE to
finish its analysis of this issue before making changes to the test
procedure. The test procedure should be revised to reference ASHRAE
Standard 37-1988, with the exception of the section that pertains to
corrections made to capacities based on measured barometric pressures,
since it is known this section contains an error and is being
revised.'' (ARI, No. 6 at 2).
Today's proposed test procedure reflects the recommendation made by
ARI.
6. Sections 3.5.3 and 3.8.1. Cyclic Degradation Coefficients
In the existing DOE test procedure, the default values provided for
cooling and heating cyclic degradation coefficients,
CcD and ChD, are both 0.25.
On the cooling side, the two optional tests are conducted on the
majority of units because the experimentally-determined
CcD is lower than 0.25. NIST, DOE and ARI members
have discussed developing new defaults. The goal is to obtain more
representative defaults resulting in less CD testing
[[Page 6776]]
while still crediting features that enhance cyclic performance. The
manufacturers and ARI, as part of their certification program, have
experimentally determined the CD of many units. DOE believes
the available data could be used to evaluate a set of new defaults that
depend on the hardware components of the air conditioner or heat pump.
The compiling of the data, however, is a formidable and thus far
uncompleted task.
ARI originally commented: ``ARI endorses the concept of providing
alternate degradation coefficients (CD) for systems using
specific components known to reduce the typical 0.25 default value.
This could significantly reduce test burden by decreasing the need for
the cumbersome cyclic test. ARI will continue to work with NIST on this
effort, and provide whatever data our members authorize, to help
determine appropriate alternatives.'' (ARI, No. 6 at 3). More recently,
ARI members have reconsidered the merits of seeking new CD
defaults. A final decision from ARI is pending.
DOE encourages ARI to provide data and recommendations needed to
begin the investigation into better CD defaults. If better
CD defaults are identified, DOE will initiate steps to
implement defaults that are lower than the existing values of 0.25.
Such lower defaults could only positively impact the SEER and HSPF of a
unit and so would not require adjustments to the existing NAECA energy
conservation standards. Defaults that are higher than the existing 0.25
values, which could only negatively impact SEER and HSPF, would most
likely become effective the same time as new NAECA energy conservation
standards. We will not delay efforts to move today's proposed
rulemaking into a final rulemaking by the pursuit of better CD
defaults. If we identify better defaults in sufficient time before the
issue of the final rule, so we can obtain public comments on the
proposed CD values, then we will incorporate the better
defaults into the final rulemaking. If better defaults are identified
after the final rulemaking, DOE will initiate a new rulemaking process
where changes and comments are limited to the issue of new CD
defaults.
E. Calculations of Seasonal Performance Descriptors
1. Sections 4.1.4 and 4.2.4. Variable-speed Bin Calculations
In the existing DOE air conditioner and heat pump test procedure, a
quadratic fit is used to approximate the change in EER and COP as a
function of the outdoor bin temperature. Prior to the 25 September 1997
DOE workshop, consideration had been given to using an alternative fit,
a linear over linear rational function of the form
Y=(A0+A1X)/
(1+B1X). The rationale function was considered
because it maintains a monotonic shape in all cases whereas a quadratic
fit can have an inflection point between the points that it is fitting.
For the purposes of interpolating the EER or COP of a variable-speed,
all-electric heat pump or air conditioner, both fits are expected to
give comparable results because the points being fitted have
historically been close to linear. For the one variable-speed heat pump
considered by NIST, for example, the two fits resulted in SEER and HSPF
changes of 0.06% and 0.14%, respectively.
At the 25 September 1997 DOE workshop, the issue was discussed.
Trane spoke against adopting the rational function on the basis that no
practical problems had arisen with using the quadratic fit over the
approximately 15 years that it has been used. (Trane, No. 2HH at 149-
150).
Today's proposed test procedure maintains the use of the quadratic
fit.
IV. Summary of Proposed Modifications to the DOE Air Conditioner
and Heat Pump Test Procedure
In addition to the modifications cited in Section III, the proposed
test procedure also incorporates the following changes.
A. Update and Add References for ASHRAE and ARI Standards
The existing test procedure references ASHRAE Standards 37-78 and
41.1 (no year) and ARI Standards 210-79, 240-77, and 320-76. The
proposed revised version references ARI Standard 210/240-94 and ASHRAE
Standards 23-93, 37-88, 41.1-86 (RA 91), 41.2-87 (RA 92), 41.6-94,
41.9-88, 51-99, and 116-95.
B. Air Volume Rates
ARI Standard 240-77 was previously referenced. Now, rather than
referencing ARI Standard 210/240-94, we have added sections within this
proposed test procedure. The main reason for no longer referencing ARI
Standard 210/240 is that it does not cover variable-speed, constant CFM
blowers and does not directly address two-capacity and variable-speed
systems. It is preferable to have the overall issue of air volume rates
covered in one place rather than in two. The main objective is to agree
on air flow rate specifications. If ARI Standard 210/240 is revised to
cover these systems, DOE may again reference the ARI Standard.
ASHRAE Standard 37-78 (or 37-88) is no longer referenced for the
equation calculating the air volume rate of standard air. The factor
1+Wn is missing from the denominator of the equation given
in Standard 37-88. This change has been adopted by the committee
working to revise Standard 37.
Today's proposed test procedure adopts the approach used in the ISO
Standard 5151 of conducting each test at zero external static pressure
when testing a non-ducted unit.
C. Cyclic Testing
Industry practice and the method described in ASHRAE Standard 116
was adopted. Section 5.1 of the current Appendix M implies that the air
volume rate is to be measured during cyclic tests. Standard test
laboratory practice is to try to obtain the same velocity pressure or
nozzle static pressure drop that was obtained during the comparable
steady-state test. The air volume rate used in the cyclic test
calculations is assumed to be the same air volume rate measured during
the comparable steady-state test. This change is reflected in this
proposed test procedure.
Concerning split-type non-ducted (ductless) systems, Section
4.1.1.5 of Appendix M states that ``The integration time for capacity
and power shall be from compressor cut-on time to indoor fan cutoff
time.'' The indoor fan is operated for 3 minutes prior to compressor
cut-on and for 3 minutes after compressor cutoff during the final OFF/
ON interval. This proposed test procedure adopts industry practice and
integrates power from compressor OFF to compressor OFF and subtracts
the electrical energy associated with operating the indoor fan during
the initial 3-minute fan-only period. Space cooling capacity is
integrated from compressor ON to indoor fan OFF. As with the present
test procedure, fan energy for the three minutes after compressor
cutoff is added to the integrated cooling capacity.
The present test procedure does not contain specific information
regarding the air dampers: where to install them, how well they should
seal, and how quickly they should respond. Much of this information is
given in Appendix B of ARI Standard 210/240-94. Needed information is
incorporated within the text of the proposed test procedure rather than
making specific references to each pertinent section of Appendix B of
the ARI Standard.
For dry coil tests, the proposed test procedure adopts ARI Standard
210/
[[Page 6777]]
240-94 Appendix B language with regard to the requirement that the
drain pan be plugged and that the pan should be completely dry.
This notice of proposed rulemaking clarifies that the requirement
of making electrical energy measurements using an instrument having an
accuracy of 0.5 percent of reading applies during both the
ON and OFF intervals of cyclic tests.
Existing Section 4.1.3.1, which reads ``The indoor and outdoor
average dry-bulb temperature for the cyclic dry coil test D shall both
be within 1.0 deg.F of the indoor and outdoor average dry bulb
temperature for the steady-state dry coil test C, respectively,'' has
been removed from the proposed test procedure. This requirement is
automatically met given the 0.5 deg.F test condition tolerance
associated with each test.
For units having a variable-speed indoor fan, the manufacturer will
have the option of conducting the cyclic tests with the indoor fan
enabled or disabled, the latter being the default option if an attempt
at testing with the fan enabled is unsuccessful. Specifically, if
testing with the indoor fan operating and it automatically reverses,
shuts down, or operates at an uncharacteristically high external static
pressure, then a pull-thru method, where the fan is disabled, must be
used. Although allowing the option of testing with the fan disabled is
needed because of the potential fighting between the unit's fan and the
exhaust fan of the air flow measuring apparatus, DOE seeks data from
cyclic tests where the fan operates versus tests where the fan is
disabled and the pull-thru method is used.
Although a unit having a variable-speed indoor fan may be designed
to ramp its fan speed when cycling on and/or off, a step response in
air volume rate is nonetheless required during cyclic tests. The work
associated with moving the additional air during the ramp periods is
performed by the exhaust fan of the air flow measuring apparatus. The
step response begins at the initiation of ramp up and ends at the
termination of ramp down. The rationale for imposing the step change is
mainly due to the difficulty in obtaining the ramp response and then
making an accurate measurement of the space conditioning delivered.
Systems having indoor fans that ramp are expected to have low cyclic
degradation coefficients (CD) regardless of whether the ramp
feature is used, thus the absolute improvement in CD is
expected to be minor. Still, the proposed method of testing will
benefit these units. DOE has only been able to obtain data from one
unit where two different ramp profiles were compared to the results
from imposing step responses in air flow. In one case CD
went from 0.05 (``truth'': ramp) to 0.02 (approximation: step change)
while in the second case the values were 0.025 and 0.00. DOE seeks
additional data showing the difference between the ramp and step
responses during cyclic tests.
D. Fanless (Coil-only) Units
Section 4.1 of the existing Appendix M calls for corrections to
capacity and power based on CFM. Section 4.2 of existing Appendix M
calls for corrections to capacity and power based on SCFM. ITS uses
SCFM in all cases. Thus, the proposed test procedure adopts the
practice of only specifying the corrections in terms of SCFM.
The proposed test procedure also adopts the ARI Standard 210/240-94
Appendix B requirement that a specific enclosure be constructed (1 inch
ductboard) when testing a coil only unit that does not employ an
enclosure.
E. Frost Accumulation Test
The proposed test procedure adopts the ASHRAE Standard 116-95 and
ARI 210/240-94 convention of specifying the outdoor wet bulb
temperature (33 deg.F) in place of the presently specified dew point
temperature (30 deg.F).
F. Test Tolerance Tables
The current Appendix M contains tables covering all tests except
steady-state cooling mode tests, for which Table III in ASHRAE Standard
37-78 is referenced. Table III of ASHRAE Standard 37-78 has been added
to the proposed test procedure since all the other tables are included
in Appendix M.
The test tolerance tables have been improved. For example, although
a test condition tolerance for external resistance to air flow is
provided in the current test procedure, it is not applicable for ducted
units. Such a test condition tolerance is, however, now applicable to
non-ducted units. Also, a test condition tolerance has been added for
electrical supply voltage (previously, only a test operating tolerance
was specified). Because ASHRAE Standard 37-78 does not cover cooling
mode dry coil tests, a test condition tolerance on the indoor inlet wet
bulb temperature is not applicable. Test tolerances given on the
outdoor outlet dry and wet bulb temperatures are now noted as only
being applicable when the Outdoor Air Enthalpy Method is used to
provide the secondary capacity measurement.
For the Frost Accumulation Test, the intervals considered to be
heating versus defrosting have been modified slightly. Specifically, in
the existing test procedure in Section 4.2.3.3, the first 5 minutes
after a defrost termination was included in the defrost interval. In
the proposed test procedure, the time interval has been increased to 10
minutes. Also, in making the test condition conversion of 30 deg. F dew
point to 33 deg. F wet bulb, the test operating tolerance and test
condition tolerance convert to wet bulb temperature tolerances of
0.6 deg. F and 0.3 deg. F, respectively. This 0.6 deg. F test operating
tolerance on outdoor wet bulb temperature is more stringent than the
value allowed for the steady-state tests. The 0.3 deg. F test condition
tolerance is the same as required for steady-state tests. Given that
these tolerances should be less stringent that those required of a
steady-state test, the proposed test procedure adopts the values given
in ASHRAE Standard 37: 1.5 deg. F and 0.5 deg. F.
G. Pretest Intervals
Statements given in the DOE proposed test procedure regarding
operation prior to recording data have been modified. These changes are
as follows.
1. Wet Coil Tests
Existing: ``The test room reconditioning apparatus and the
equipment under test shall be operated until equilibrium conditions are
attained'' (Section 4.1.1.1).
Proposed: ``For the pretest interval, operate the test room
reconditioning apparatus and the unit to be tested until maintaining
equilibrium conditions for at least 30 minutes at the specified Section
3.2 test conditions'' (Section 3.3).
2. Dry Coil Steady-State Test
Existing: ``The test room reconditioning apparatus and the
equipment under test shall be operated until equilibrium conditions are
attained, but not for less than one hour before data for test C are
recorded'' (Section 4.1.1.2).
Proposed: Same as proposed for Section 3.3 wet coil tests with the
additional requirement to `` * * * operate the unit at least one hour
after achieving dry coil conditions'' (Section 3.4).
3. Dry Coil Cyclic Test
Existing: `` * * * test unit shall be manually cycled `off ' and
`on' * * * until steadily repeating ambient conditions are again
achieved in both the indoor and outdoor test chambers, but for not less
than two complete `off/on' cycles'' (Section 4.1.1.2).
Proposed: ``After completing a minimum of two complete compressor
[[Page 6778]]
OFF/ON cycles, determine the overall cooling delivered and total
electrical energy consumption during any subsequent data collection
interval where the test tolerances given in Table 8 are satisfied''
(Section 3.5).
4. Maximum and High Temperature Heating Mode Tests
Existing: ``The test room apparatus and test units must be operated
for at least one hour with at least one-half hour at equilibrium and at
the specified test conditions prior to starting the test'' (Section
4.2.1.1).
Proposed: ``For the pretest interval, operate the test room
reconditioning apparatus and the heat pump until equilibrium conditions
are maintained for at least 30 minutes at the specified Section 3.6
test conditions'' (Section 3.7).
5. Heating Mode Cyclic Test
Existing: `` * * * and be cycled `on' and `off' as specified in
3.2.1.2 until steadily repeating ambient conditions are achieved for
both the indoor and outdoor test chambers, but for not less than two
complete `off'/`on' cycles'' (Section 4.2.1.2).
Proposed: Same as for the dry coil cooling mode cyclic test (see
above).
6. Frost Accumulation Test
Existing: ``The test room reconditioning equipment and the unit
under test shall be operated for at least one-half hour prior to the
start of a `preliminary' test period'' (Section 4.2.1.3).
Proposed: ``Operate the test room reconditioning apparatus and the
heat pump for at least 30 minutes at the specified Section 3.6 test
conditions before starting the `preliminary' test period'' (Section
3.9).
7. Low Temperature Test
Existing: ``The test room reconditioning equipment shall first be
operated in a steady-state manner for at least one-half hour at
equilibrium and at the specified test conditions. The unit shall then
undergo a defrost, either automatic or manually induced'' (Section
4.2.1.4).
Proposed: Same as for the Maximum and High Temperature Heating mode
tests (see above) with the following additions. ``After satisfying the
Section 3.7 requirements for the pretest interval, but before you begin
collecting data to determine Qh\k\(17) and
Eh\k\(17), conduct a defrost cycle. This defrost cycle may
be manually or automatically initiated. (Section 3.10).
H. Multi-Capacity Systems
1. Two-Capacity Heat Pumps that Lock Out Low Capacity at Higher Outdoor
Temperatures.
The existing test procedure covers two-capacity units that operate
exclusively at high capacity when the building load exceeds the unit's
low capacity. The Department is unaware of any two-capacity units that
implement such a control strategy and so coverage of them is excluded
from today's proposed test procedure. However, coverage was added to
address units that lock out low capacity operation at low (heating) or
high (cooling) outdoor temperatures. For this new case, a step was
added which reverts to a single capacity calculation. The proposed test
procedure uses the CD determined based on cycling at low
capacity (or the 0.25 default) in all cases. The Department welcomes
comments on any control strategy used by two-capacity units that are
not adequately covered in today's proposed test procedure.
2. Systems Having a Single-Speed Compressor and a Variable-Speed Indoor
Fan Where Fan Speed or Air Volume Rate Depends on Outdoor Temperature.
The proposed test procedure requires two extra steady-state tests
for the cooling mode (see Table 4) and two extra steady-state tests for
the heating mode (see Table 10). An extra Frost Accumulation test is
optional.
3. Specification of the Air Volume Rate for Tests at Low Capacity
In the existing test procedure, the air volume rate to be used when
testing a two capacity system while operating at low capacity is not
explicitly addressed. The proposed test procedure requires the use of
the fan laws, as is now done for variable-speed systems, to determine
the air volume rate when testing a unit having an indoor fan. For
fanless units, the air volume rate used when conducting tests at low
capacity (i.e., the Minimum Air Volume Rate) is the higher of
(1) The rate specified by the manufacturer; or
(2) 75 percent of the air volume rate used for the high capacity
tests.
DOE believes that a lower limit is needed given the finite
capabilities of the typical multi-speed furnace blower that is used in
field installations. The 75 percent minimum is based on very limited
data collected by NIST. The subject has been discussed by industry
members at such forums as ASHRAE meetings but no formal consensus has
yet been reached for the specified percentage. Data and comments are
requested, especially with regard to the specified value of the lower
limit.
I. Triple-split Systems
The DOE test procedure refers to ASHRAE Standard 37 on the issue of
equipment installation and test set up procedures. ASHRAE Standard 37,
in turn, states that you must use the calorimeter air-enthalpy method
arrangement when testing units where the compressor is in the indoor
section and separately ventilated. For this arrangement, an enclosure
must be built around the equipment under test within the indoor
chamber. The present requirement is burdensome and DOE knows of no one
who uses it when testing triple-splits. Furthermore, the heat loss from
the indoor compressor section should be reflected in an adjusted output
capacity and not by a raised entering air temperature. The amount of
heat dissipated to the ambient by the indoor compressor section of such
units is usually minimized as a result of the enclosure of the third
section being insulated (mainly in an effort to reduce the operating
noise). Based on limited information gained to date, the amount of heat
lost from the indoor compressor section is on the order of 2 percent or
less of the unit's space conditioning capacity.
The proposed test procedure instructs that triple-split systems are
not to be tested using the calorimeter air-enthalpy method arrangement
(see note in Section 2.6). At this juncture, no algorithm or method for
assigning/determining the heat loss from the indoor compressor section
is included. If triple-split systems become more popular and if
information becomes available indicating the heat loss from the indoor
compressor section exceeds 2 percent of the total, air-side capacity,
then DOE will revisit the option of having a capacity adjustment.
J. Time-Adaptive Defrost Control Systems
When conducting a Frost Accumulation test on a heat pump having a
time-adaptive defrost control system, repeatable frosting and
defrosting intervals typically require (if obtainable at all) an
excessive number of cycles. Until a better alternative is identified,
defrosts initiated during the ``preliminary'' test and the ``official''
test will be manually induced. The manufacturer will be required to
provide information as to how long the unit would optimally frost
before initiating a defrost. The manufacturer will have to provide
information on
[[Page 6779]]
how to induce a defrost cycle at the appropriate elapsed time. The
controls of the unit, however, will still control the duration of the
defrost cycle, once initiated.
K. Test Unit Installation
For the most part, equipment installation requirements will
continue to be performed according to the manufacturer's installation
instructions. However, the proposed test procedure adopts the lab and
field practice of insulating the low pressure line(s) of a split
system. Also, Section 2.2.5 restricts the use of special refrigerant
charging criteria for lab testing.
L. Test Apparatus and Measurement/Sampling Frequency
1. Inlet Plenum for Blower Coils
In the current DOE test procedure, no inlet plenum is required when
testing blower coil units. The proposed test procedure recommends that
an inlet plenum be installed if space permits. (Lab ceiling height on
vertical installation is a limitation.) The test procedure recommends
using an inlet plenum that is constructed according to the design
specified for fanless units. See Section 2.4.2.
2. Manifolded Static Pressure Taps
The triple-T configuration was found in 1976 to be the preferred
method for manifolding static pressure taps (``The design of piezometer
rings'' by K. A. Blake, Journal of Fluid Mechanics, Vol. 78, part 2,
pp. 415-428). The triple-T configuration and the more widely used
complete ring, four-to-one manifolding configuration are presently part
of the draft revision of ASHRAE Standard 37. This revised test
procedure recommends use of either of these two manifolding methods,
which are shown in Figure 1. The broken ring, four-to-one manifolding
configuration may be used but is not recommended.
3. Temperature Measurement Intervals
The proposed test procedure specifies that dry-bulb temperature
measurements are to be measured at the intervals specified in ASHRAE
Standard 41.1-86 (RA91). Wet bulb temperature, dew point temperature,
or relative humidity are to be measured at the minimum sampling
interval specified in Definition 1.14.
4. Temperature Measurement Accuracies
The proposed test procedure defers entirely to ASHRAE Standard
41.1-86 (RA 91) for accuracy and precision requirements.
5. Grid of Individual Temperature Sensors Within the Indoor-Side Outlet
Plenum
The proposed test procedure adopts the ARI Standard 210/240-94
Appendix B requirements that a temperature spread of 1.5 deg.F or less
be obtained, and that the outlet temperature grid be composed of a
minimum of 9 sensors (while recommending 16). Also, the proposed test
procedure recommends redundant sensors to determine the change in dry
bulb temperature across the indoor coil.
6. Duct Loss Correction
The proposed test procedure adds a correction for the heat transfer
between the test room and an outlet duct sandwiched between the coil
and the outlet temperature grid. This correction is already an industry
practice.
7. Water vapor measurements using a dew-point hygrometer, a relative
humidity meter, or any other alternative instrument
Today's test procedure explicitly permits alternatives to using wet
bulb temperature sensors. To ease instrumentation selection, required
instrument accuracies are provided for dew point hygrometers and
relative humidity meters.
8. Voltmeter Accuracy
The required accuracy of voltage measurements has been changed from
2% to 1%.
9. Electrical Power Measurement
Adjustable-speed-driven motors, as used in a variable-speed
compressor, distort the input current and, to a lesser degree, voltage
waveforms. Published literature [1-7] supports avoiding the use of
induction type meters for measuring such non-sinusoidal power and
instead recommends using a meter that is capable of sampling up to the
50th harmonic. This point is included in Section 2.8 of today's test
procedure as a recommendation when testing a heat pump or air
conditioner having a variable-speed compressor. (In terms of a meter
sampling frequency, a 50th harmonic requirement corresponds to a
minimum sampling frequency between 3 and 30 kHz, depending upon which
technical recommendation you wish to cite.)
The majority of the technical references listed below report the
performance of specific meters with specific waveforms, some of which
should be representative of those found in presently-marketed
residential-size air conditioners and heat pumps. In addition to
induction watthour meters, a disconcerting result reported in the noted
references is that the use of a non-induction meter that can measure up
to the 50th harmonic does not insure an accurate measurement but only
improves your chances.
References:
1. P.S. Filipski and R. Arseneau, ``Behavior of Wattmeters and
Watthour Meters Under Distorted Waveform Conditions,'' IEEE tutorial
course, Nonsinusoidal Situations: Effects on the Performance of
Meters and Definitions of Power, IEEE, Piscataway, NJ, pp. 13-22,
1990.
2. A. Domijan, Jr., E. Embriz-Santander, A.J. Gilani, G. Lamer, C.
Stiles, and C.W. Williams, Jr., ``Watthour Meter Accuracy Under
Controlled Unbalanced Harmonic Voltage and Current Conditions,''
IEEE Transactions Power Delivery, Vol. II, No. 1, pp. 64-78, Jan.
1996.
3. A. Domijan, D. Czarkowski, A. Abu-aisheh, and E. Embriz-
Santander, ``Measurements of Electrical Power Inputs to Variable
Speed Motors and Their Solid State Power Converters--Phase II,''
ASHRAE Research Project 770, Final Report, November 30, 1995.
4. D. Czarkowski and A. Domijan, Jr., ``Performance of Electrical
Power Meters and Analyzers in Adjustable-Speed Drive Applications,''
American Society of Heating, Refrigerating and Air-Conditioning
Engineers (ASHRAE) Transactions 1997, Vol. 103, Part 1.
5. A.J. Baldwin, N.G. Planer, D.E. Nordell, N. Hohan, ``Evaluation
of Electrical Interference to the Induction Watthour Meter,'' EPRI
EL-2315, Research Project 1738, Final Report, April 1982.
6. Institute of Electrical and Electronics Engineers (IEEE), Inc.,
``IEEE Standard 519-1992, IEEE Recommended Practices and
Requirements for Harmonic Control in Electrical Power Systems,'' New
York, New York.
7. A. Domijan, and E. Embriz-Santander, ``Measurements of Electrical
Power Inputs to Variable Speed Motors and Their Solid State Power
Converters,'' American Society of Heating, Refrigerating and Air-
Conditioning Engineers (ASHRAE) Transactions 1993, Vol. 99, Part I,
pp. 241-258.
M. Different Compressor Speeds and Indoor Fan Capacities Between
Cooling and Heating
In the existing test procedure, variable-speed systems that operate
at higher speeds when heating than when cooling are covered. In today's
proposed revision (as noted above in III.D.4) this allowance has been
extrapolated to coverage of two-capacity heat pumps that only operate
at low capacity during the cooling season while using both low and high
capacities when heating. And, in taking a generic approach, today's
test procedure covers any case where the heat pump uses different fan
speeds or air volume rates for cooling versus when heating. (See
Section 3.1.4.4.2)
[[Page 6780]]
N. Secondary Test Requirements.
When using the Outdoor Air Enthalpy test method, a preliminary test
is conducted to compensate, if necessary, for any performance impact
caused by the outdoor air-side test apparatus. In accordance with the
existing test procedure, a preliminary test is conducted prior to all
steady-state tests (i.e., those tests where a secondary measurement of
capacity is required). In today's revision, relaxing this requirement
is proposed. Section 3.11.1 indicates that the number of preliminary
tests can be reduced in most cases to one (for air conditioners or
heating-only heat pumps) or two (for heat pumps): one for the first
cooling mode steady-state test and one for the first heating mode
steady-state test.
O. HSPF Calculations
The last paragraph of Sections 5.2.1 and 5.2.2 of the existing test
procedure are not similarly placed in the proposed test procedure. The
paragraph in question reads ``Once the maximum and minimum HSPF and
operating cost values have been obtained for each region, the HSPF and
operating cost shall be determined for each standardized design heating
requirement (see section 6.2.6) between the maximum and minimum design
heating requirements by means of interpolation.'' The issue of how many
HSPF calculations are required has been, and will remain, an item that
is covered elsewhere: In 10 CFR part 430, subpart B,
Sec. 430.23(m)(3)(ii). In the proposed test procedure, this section
along with a short restatement of its contents are included in the
Definition (1.27) for HSPF. Because of the relative ease of automating
the calculation process, and the nonlinearity of the HSPF versus design
heating requirement relationship, no reference is made to obtaining
HSPF or operating cost via interpolation.
V. Procedural Requirements
A. Review Under the National Environmental Policy Act of 1969
In this notice, the Department proposes amendments to the test
procedures for central air conditioners and heat pumps. We have
reviewed the proposed rule under the National Environmental Policy Act
of 1969 (NEPA), 42 U.S.C. 4321 et seq., the regulations of the Council
on Environmental Quality, 40 CFR parts 1500-1508, DOE regulations for
compliance with NEPA, 10 CFR part 1021, and the Secretarial Policy on
the National Environmental Policy Act (June 1994). The Department has
determined that this rulemaking is covered under the Categorical
Exclusion found at paragraph A.6 of appendix A to subpart D, 10 CFR
part 1021, which applies to rulemakings that are strictly procedural.
This proposed rule is a procedural rulemaking and its implementation
will not affect the quality or distribution of energy usage and
therefore will not result in any environmental impacts. Accordingly,
neither an environmental assessment nor an environmental impact
statement is required.
B. Regulatory Review
Today's regulatory proposal has been determined not to be a
``significant regulatory action'' under Executive Order 12866,
``Regulatory Planning and Review,'' (58 FR 51735, October 4, 1993).
Accordingly, today's action was not subject to review under the
Executive Order by the Office of Information and Regulatory Affairs in
the Office of Management and Budget.
C. Regulatory Flexibility Review
The proposed rule has been reviewed under the Regulatory
Flexibility Act, (42 U.S.C. 601-612), which requires preparation of a
regulatory flexibility analysis for any regulation that will have a
significant economic impact on a substantial number of small businesses
and other small entities. The proposed rule affects manufacturers of
central air conditioners and heat pumps. The test procedures would not
have a significant economic impact, but rather, would provide common
testing methods. This revision of the test procedure will not require a
significant investment for new testing equipment. DOE accordingly
certifies that the proposed rule would not, if promulgated, have a
significant economic impact on a substantial number of small entities
and that preparation of a regulatory flexibility analysis is not
required.
D. ``Takings'' Assessment Review
DOE has determined pursuant to Executive Order 12630 (52 FR 8859,
March 18, 1988) that this proposed regulation, if adopted, would not
result in any takings which might require compensation under the Fifth
Amendment to the United States Constitution.
E. Federalism Review
Executive Order 13132 (64 FR 43255, August 10, 1999) requires
agencies to develop an accountable process to ensure meaningful and
timely input by State and local officials in the development of
regulatory policies that have ``federalism implications.'' Policies
that have federalism implications are defined in the Executive Order to
include regulations that have ``substantial direct effects on the
States, on the relationship between the national government and the
States, or on the distribution of power and responsibilities among the
various levels of government.'' On March 14, 2000, DOE published a
statement of policy describing the intergovernmental consultation
process it will follow in the development of such regulations (65 FR
13735). DOE has examined today's rule and determined that it does not
have a substantial direct effect on the States, on the relationship
between the national government and the States, or on the distribution
of power and responsibilities among the various levels of government.
No further action is required by the Executive Order.
F. Paperwork Reduction Act Review
This proposed rule contains no new collections of information under
the Paperwork Reduction Act, 44 U.S.C. 3501 et seq.
G. Review Under Unfunded Mandates Reform Act of 1995
Section 202 of the Unfunded Mandates Reform Act of 1995 (``Unfunded
Mandates Act'') requires that the Department prepare an impact
statement before promulgating a rule that includes a Federal mandate
that may result in expenditure by state, local, and tribal governments,
in the aggregate, or by the private sector, of $100 million or more in
any one year. The impact statement must include: (i) Identification of
the Federal law under which the rule is promulgated; (ii) a qualitative
and quantitative assessment of anticipated costs and benefits of the
Federal mandate and an analysis of the extent to which such costs to
state, local, and tribal governments may be paid with Federal financial
assistance; (iii) if feasible, estimates of the future compliance costs
and of any disproportionate budgetary effects the mandate has on
particular regions, communities, non-Federal units of government, or
sectors of the economy; (iv) if feasible, estimates of the effect on
the national economy; and (v) a description of the Department's prior
consultation with elected representatives of state, local, and tribal
governments and a summary and evaluation of the comments and concerns
presented.
The Department has determined that the action proposed today does
not include a Federal mandate that may result in estimated costs of
$100 million
[[Page 6781]]
or more to state, local or to tribal governments in the aggregate or to
the private sector. Therefore, the requirements of sections 203 and 204
of the Unfunded Mandates Act do not apply to this action.
H. Review Under Executive Order 12988, ``Civil Justice Reform''
With respect to the review of existing regulations and the
promulgation of new regulations, section 3(a) of Executive Order 12988,
``Civil Justice Reform,'' 61 FR 4729 (February 7, 1996), imposes on
executive agencies the general duty to adhere to the following
requirements: (1) Eliminate drafting errors and ambiguity; (2) write
regulations to minimize litigation; and (3) provide a clear legal
standard for affected conduct rather than a general standard and
promote simplification and burden reduction. With regard to the review
required by Section 3(a), section 3(b) of the Executive Order
specifically requires that Executive agencies make every reasonable
effort to ensure that the regulation: (1) Clearly specifies the
preemptive effect, if any; (2) clearly specifies any effect on existing
Federal law or regulation; (3) provide a clear legal standard for
affected conduct while promoting simplification and burden reduction;
(4) specifies the retroactive effect, if any; (5) adequately defines
key terms; and (6) addresses other important issues affecting clarity
and general draftsmanship under any guidelines issued by the Attorney
General. Section 3(c) of the Executive Order requires Executive
agencies to review regulations in light of applicable standards section
3(a) and section 3(b) to determine whether they are met or it is
unreasonable to meet one or more of them. DOE reviewed today's proposed
rulemaking under the standards of section 3 of the Executive Order and
determined that, to the extent permitted by law, it meets the
requirements of those standards.
I. Review Under the Treasury and General Government Appropriations Act,
1999
Section 654 of the Treasury and General Government Appropriations
Act, 1999 (Pub. L. 105-277) requires federal agencies to issue a Family
Policymaking Assessment for any proposed rule or policy that may affect
family well-being. Today's proposal would not have any impact on the
autonomy or integrity of the family as an institution. Accordingly, we
have concluded that it is not necessary to prepare a Family
Policymaking Assessment.
J. Plain Language Review
The President's Memorandum on ``Plain Language in Government
Writing,'' 63 FR 31885 (June 10, 1998) directs each federal agency to
write all published rulemaking documents in plain language. The
Memorandum includes general guidance on what constitutes ``plain
language.'' Plain language requirements will vary from one document to
another, depending on the intended audience, but all plain language
documents should be logically organized and clearly written.
We have tried to make this proposed rule easy to understand. We are
also requesting suggestions on how to improve its readability further.
VI. Public Comment Procedures
A. Written Comment Procedures
The Department invites interested persons to participate in the
proposed rulemaking by submitting data, comments, or information with
respect to the proposed issues set forth in today's proposed rule to
Ms. Brenda Edwards-Jones, at the address indicated at the beginning of
this notice. We will consider all submittals received by the date
specified at the beginning of this notice in developing the final rule.
According to 10 CFR 1004.11, any person submitting information that
he or she believes to be confidential and exempt by law from public
disclosure should submit one complete copy of the document and ten (10)
copies, if possible, from which the information believed to be
confidential has been deleted. The Department of Energy will make its
own determination with regard to the confidential status of the
information and treat it according to its determination.
Factors of interest to the Department when evaluating requests to
treat as confidential information that has been submitted include: (1)
A description of the items; (2) an indication as to whether and why
such items are customarily treated as confidential within the industry;
(3) whether the information is generally known by or available from
other sources; (4) whether the information has previously been made
available to others without obligation concerning its confidentiality;
(5) an explanation of the competitive injury to the submitting person
which would result from public disclosure; (6) an indication as to when
such information might lose its confidential character due to the
passage of time; and (7) why disclosure of the information would be
contrary to the public interest.
B. Issues for Public Comment
The Department of Energy is interested in receiving comments and
data concerning these test procedures. Also, the Department welcomes
comments on improvements or alternatives to these approaches. In
particular, DOE is interested in gathering comments on the following:
1. Non-defrost (limited-range) heat pumps
Which of the three options described in Section III.A.3 should be
invoked?
2. Testing units having a constant-air-volume-rate indoor fan
Are the proposed changes described in Section III.D.1 acceptable?
In particular, does the proposed 8 percent tolerance on indoor air
volume rate provide a fair balance between assuring repeatable results
while not being too restrictive given the variation in blower motor
performance?
3. Cyclic testing of units having a variable-speed indoor fan (that may
or may not provide a constant air volume rate)
For units that ramp the indoor fan speed when cycling on and/or
off, data are sought of the type referenced in the last paragraph of
Section IV.C (i.e., data that quantifies the effect on CD
from using a ramped air volume rate versus forcing the air volume rate
to have a step profile). Also, as described in the second-to-last
paragraph of Section IV.C, data from cyclic tests conducted with the
indoor fan enabled and disabled are sought.
4. Two-capacity heat pumps that are designed to meet the seasonal
cooling load while operating at low capacity
As discussed in the last paragraph of Section III.D.4, should the
heat pump be required to have controls that lock out high capacity
operation when cooling?
5. Lower limit on the air volume rate used when testing a fanless, two-
capacity unit at low compressor capacity
As discussed in Section IV.H.3, data and comments are requested
regarding the assigned limit for the air volume rate when testing a
fanless, two-capacity unit at low compressor capacity.
Related to this issue is whether the manufacturer should be
required to supply, with the unit, the hardware needed to allow the use
of two fan speeds on the furnace blower that the unit would be used
with in the field. Conceivably, if such hardware was not provided, the
test procedure could call for using the same air volume rate for all
[[Page 6782]]
tests, regardless of whether the compressor is operating at high or low
capacity. On the other extreme, do any manufacturers provide hardware
that allows a multi-speed furnace blower to operate as a variable-speed
blower? Or, are there safeguards that will result in all or the vast
majority of fanless, two-capacity units to be applied with furnaces
having variable-speed blowers? If so, then the lower limit noted in the
previous paragraph may not be applicable.
6. Fan defaults for fanless (i.e., coil-only) two-capacity units
In the existing test procedure, the fan heat/power default that is
applied when rating fanless units is 1250 Btu/h per 1000 SCFM (365
watts per 1000 SCFM). When testing two-capacity fanless units, this
adjustment is applied when evaluating space conditioning capacities and
electrical power usages for both high and low compressor capacity
operation. Do blower curves for multi-speed indoor fans support the use
of the same default for both low and high capacity?
7. Differentiation among two-capacity air conditioners and heat pumps
Is there a need to differentiate between two-capacity units that
can transition between high and low compressor capacities on-the-fly
versus units that must shut off the compressor for some finite time
interval when transitioning? Both the existing test procedure and
today's proposed revision do not offer a means for providing such
differentiation. To begin to do so would require information on how EER
and COP are affected as they change from the value associated with
steady operation at one compressor capacity until steady operation is
obtained at the other compressor capacity following the transition. DOE
seeks comments and data that would help to determine whether the test
procedure needs to account for low/high compressor transitioning
performance.
8. Testing single-packaged units
Today's proposed test procedure includes new test requirements when
testing certain types of single-packaged units. The proposed additions
are summarized in III.C.1. As presently proposed, the changes are
limited to cooling mode tests where all or part of the indoor section
is located in the outdoor test room and to heating mode tests where all
or part of the outdoor section is located in the indoor test room.
Comments are sought on the general proposal and on whether the
approaches should be invoked when testing all packaged units.
9. Multi-capacity units
Are there any multi-capacity units that operate at less than
maximum speed or high capacity at the lowest outdoor temperatures
(prior to cycling off the compressor, if applicable)? Possibly such a
strategy is needed to insure component reliability. Such a contingency
is not covered in the existing or proposed test procedure.
10. Cyclic degradation coefficients
Comments are sought on the proposed actions discussed above in
Section III.D.6 for working towards new CD defaults.
11. NAECA energy conservation standards
Changes introduced in today's proposed test procedure are not
expected to cause a minimally-compliant unit to now become non-
compliant. If a particular proposed change is found to negatively
affect minimally compliant units, then DOE would like to know.
12. Small-duct, high-velocity systems
Comments are sought on the proposed actions discussed in Section
III.A.2.
C. Public Workshop
1. Procedures for Submitting Requests to Speak
You will find the time and place of the public workshop listed at
the beginning of this notice of proposed rulemaking. The Department
invites any person who has an interest in today's notice of proposed
rulemaking, or who is a representative of a group or class of persons
that has an interest in these proposed issues, to make a request for an
opportunity to make an oral presentation. If you would like to attend
the public workshop, please notify Ms. Brenda Edwards-Jones at (202)
586-2945. You may hand deliver requests to speak to the address
indicated at the beginning of this notice between the hours of 8:00
a.m. and 4:00 p.m., Monday through Friday, except Federal holidays, or
send them by mail or e-mail to [email protected].
The person making the request should state why he or she, either
individually or as a representative of a group or class of persons, is
an appropriate spokesperson, briefly describe the nature of the
interest in the rulemaking, and provide a telephone number for contact.
The Department requests each person wishing to speak to submit an
advance copy of his or her statement at least 10 days prior to the date
of this workshop as indicated at the beginning of this notice. The
Department, at its discretion, may permit any person wishing to speak
who cannot meet this requirement to participate if that person has made
alternative arrangements with the Office of Building Research and
Standards in advance. The letter making a request to give an oral
presentation must ask for such alternative arrangements.
2. Conduct of Workshop
The workshop (hearing) will be conducted in an informal, conference
style. The Department may use a professional facilitator to facilitate
discussion, and a court reporter will be present to record the
transcript of the meeting. We will present summaries of comments
received before the workshop, allow time for presentations by workshop
participants, and encourage all interested parties to share their views
on issues affecting this rulemaking. Following the workshop, we will
provide an additional comment period, during which interested parties
will have an opportunity to comment on the proceedings at the workshop,
as well as on any aspect of the rulemaking proceeding.
The Department will arrange for a transcript of the workshop and
will make the entire record of this rulemaking, including the
transcript, available for inspection in the Department's Freedom of
Information Reading Room. Any person may purchase a copy of the
transcript from the transcribing reporter.
List of Subjects in 10 CFR Part 430
Administrative practice and procedure, Energy conservation,
Household appliances, Incorporation by reference.
Issued in Washington, DC., on December 19, 2000.
Dan W. Reicher,
Assistant Secretary, Energy Efficiency and Renewable Energy.
For the reasons set forth in the preamble, part 430 of Chapter II
of Title 10, Code of Federal Regulations is proposed to be amended as
set forth below:
PART 430--ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS
1. The authority citation for Part 430 continues to read as
follows:
Authority: 42 U.S.C. 6291-6309; 28 U.S.C. 2461 note.
2. Section 430.22 is amended:
[[Page 6783]]
a. By adding paragraphs (b)(5)3. through (b)(5)10.;
b. by adding paragraph (b)(7).
The additions specified above read as follows:
Sec. 430.22 Reference Sources.
* * * * *
(b) * * *
(5) * * *
3. American Society of Heating, Refrigerating, and Air-
Conditioning Engineers Standard 23-1993, ``Methods of Testing for
Rating Positive Displacement Refrigerant Compressors and Condensing
Units.''
4. American Society of Heating, Refrigerating, and Air-
Conditioning Engineers Standard 37-1988, ``Methods of Testing for
Rating Unitary Air-Conditioning and Heat Pump Equipment.''
5. American Society of Heating, Refrigerating, and Air-
Conditioning Engineers Standard 41.1-1986 (Reaffirmed 1991),
``Standard Method for Temperature Measurement.''
6. American Society of Heating, Refrigerating, and Air-
Conditioning Engineers Standard 41.2-1987 (Reaffirmed 1992),
``Standard Method for Laboratory Airflow Measurement.''
7. American Society of Heating, Refrigerating, and Air-
Conditioning Engineers Standard 41.6-1994, ``Method for Measurement
of Moist Air Properties.''
8. American Society of Heating, Refrigerating, and Air-
Conditioning Engineers Standard 41.9-1988, ``A Standard Calorimeter
Test Method for Flow Measurement of a Volatile Refrigerant.''
9. American Society of Heating, Refrigerating, and Air-
Conditioning Engineers/Air Moving and Conditioning Association, Inc.
Standard 51-1999, ``Laboratory Methods of Testing Fans for Rating.''
10. American Society of Heating, Refrigerating, and Air-
Conditioning Engineers Standard 116-1995, ``Methods of Testing for
Rating for Seasonal Efficiency of Unitary Air Conditioners and Heat
Pumps.''
* * * * *
(7) Air-Conditioning and Refrigeration Institute (ARI), 4301 North
Fairfax Drive, Suite 425, Arlington, Virginia 22203, (703) 524-8800,
ARI Standard 210/240-1994, ``Unitary Air-Conditioning and Air-Source
Heat Pump Equipment.''
* * * * *
3. Appendix M to Subpart B is revised to read as follows:
Appendix M to Subpart B--Uniform Test Method for Measuring the Energy
Consumption of Central Air Conditioners and Heat Pumps
1. Definitions
2. Testing Conditions
2.1 Test room requirements
2.2 Test unit installation requirements.
2.2.1 Defrost control settings
2.2.2 Special requirements for units having a multiple-speed
outdoor fan.
2.2.3 Special requirements for multi-split air conditioners and
heat pumps, and systems composed of multiple mini-split units
(outdoor units located side-by-side) that would normally operate
using two or more indoor thermostats.
2.2.4 Wet-bulb temperature requirements for the air entering
the indoor and outdoor coils.
2.2.4.1 Cooling mode tests.
2.2.4.2 Heating mode tests.
2.2.5 Additional refrigerant charging requirements
2.3 Indoor air volume rates.
2.3.1 Cooling tests.
2.3.2 Heating tests.
2.4 Indoor coil inlet and outlet duct connections.
2.4.1 Outlet plenum for the indoor coil.
2.4.2 Inlet plenum for the indoor unit
2.5 Indoor coil air property measurements and air damper box
applications
2.5.1 Test set-up on the inlet side of the indoor coil: for
cases where the inlet damper box is installed
2.5.1.1 If the Section 2.4.2 inlet plenum is installed.
2.5.1.2 If the Section 2.4.2 inlet plenum is not installed
2.5.2 Test set-up on the inlet side of the indoor unit: for
cases where no inlet damper box is installed.
2.5.3 Indoor coil static pressure difference measurement
2.5.4 Test set-up on the outlet side of the indoor coil.
2.5.4.1 Outlet air damper box placement and requirements
2.5.4.2 Additional recommendations
2.5.5 Dry bulb temperature measurement
2.5.6 Water vapor content measurement
2.5.7 Air damper box performance requirements
2.6 Airflow measuring apparatus
2.7 Electrical voltage supply
2.8 Electrical power and energy measurements
2.9 Time measurements.
2.10 Test apparatus for the secondary space conditioning capacity
measurement
2.10.1 Outdoor Air Enthalpy Method
2.10.2 Compressor Calibration Method
2.10.3 Refrigerant Enthalpy Method.
2.11 Measurement of test room ambient conditions
2.12 Measurement of indoor fan speed
2.13 Measurement of barometric pressure
3. Testing Procedures
3.1 General Requirements
3.1.1 Primary and secondary test methods.
3.1.2 Manufacturer-provided equipment overrides.
3.1.3 Airflow through the outdoor coil.
3.1.4 Airflow through the indoor coil.
3.1.4.1 Cooling Certified Air Volume Rate.
3.1.4.1.1 Cooling Certified Air Volume Rate for Ducted Units.
3.1.4.1.2 Cooling Certified Air Volume Rate for Non-ducted
Units.
3.1.4.2 Cooling Minimum Air Volume Rate.
3.1.4.3 Cooling Intermediate Air Volume Rate.
3.1.4.4 Heating Certified Air Volume Rate
3.1.4.4.1 Ducted heat pumps where the Heating and Cooling
Certified Air Volume Rates are the same.
3.1.4.4.2 Ducted heat pumps where the Heating and Cooling
Certified Air Volume Rates are different due to indoor fan
operation.
3.1.4.4.3 Ducted heating-only heat pumps.
3.1.4.4.4 Non-ducted heat pumps, including non-ducted heating-
only heat pumps.
3.1.4.5 Heating Minimum Air Volume Rate.
3.1.4.6 Heating Intermediate Air Volume Rate.
3.1.4.7 Heating Nominal Air Volume Rate.
3.1.5 Indoor test room requirement when the air surrounding the
indoor unit is not supplied from the same source as the air entering
the indoor unit.
3.1.6 Air volume rate calculations.
3.1.7 Test sequence.
3.1.8 Requirement for the air temperature distribution leaving
the indoor coil.
3.1.9 Control of auxiliary resistive heating elements.
3.2 Cooling mode tests for different types of air conditioners and
heat pumps.
3.2.1 Tests for a unit having a single-speed compressor that is
tested with a fixed-speed indoor fan installed, with a constant-air-
volume-rate indoor fan installed, or with no indoor fan installed.
3.2.2 Tests for a unit having a single-speed compressor and a
variable-speed variable-air-volume-rate indoor fan installed.
3.2.2.1 Indoor fan capacity modulation that correlates with the
outdoor dry bulb temperature.
3.2.2.2 Indoor fan capacity modulation based on adjusting the
sensible to total (S/T) cooling capacity ratio.
3.2.3 Tests for a unit having a two-capacity compressor.
3.2.4 Tests for a unit having a variable-speed compressor.
3.3 Test procedures for steady-state wet coil cooling mode tests
3.4 Test procedures for the optional steady-state dry coil cooling
mode tests
3.5 Test procedures for the optional cyclic dry coil cooling mode
tests (the D, D1, and I1 Tests)
3.5.1 Procedures when testing ducted systems.
3.5.2 Procedures when testing non-ducted systems
3.5.3 Cooling mode cyclic degradation coefficient calculation.
3.6 Heating mode tests for different types of heat pumps, including
heating-only heat pumps.
3.6.1 Tests for a heat pump having a single-speed compressor
that is tested with a fixed speed indoor fan installed, with a
constant-air-volume-rate indoor fan installed, or with no indoor fan
installed.
3.6.1.1 Non-defrost heat pump.
3.6.1.2 Heat pump having a heat comfort controller.
[[Page 6784]]
3.6.2 Tests for a heat pump having a single-speed compressor
and a variable-speed, variable-air-volume-rate indoor fan: capacity
modulation correlates with outdoor dry bulb temperature.
3.6.3 Tests for a heat pump having a two-capacity compressor
3.6.4 Tests for a heat pump having a variable-speed compressor.
3.7 Test procedures for steady-state Maximum Temperature and High
Temperature heating mode tests (the H0, H01, H1,
H12, H11, and H1N Tests).
3.8 Test procedures for the optional cyclic heating mode tests (the
H0C1, H1C, and H1C1 Tests).
3.8.1 Heating mode cyclic degradation coefficient calculation.
3.9 Test procedures for Frost Accumulation heating mode tests
3.9.1 Average space heating capacity and electrical power
calculations
3.9.2 Demand defrost credit
3.10 Test procedures for steady-state Low Temperature heating mode
tests
3.11 Additional requirements for the secondary test methods
3.11.1 If using the Outdoor Air Enthalpy Method as the
secondary test method
3.11.1.1 If a preliminary test precedes the official test
3.11.1.2 If a preliminary test does not precede the official
test
3.11.1.3 Official test
3.11.2 If using the Compressor Calibration Method as the
secondary test method
3.11.3 If using the Refrigerant Enthalpy Method as the
secondary test method
3.12 Rounding of space conditioning capacities for reporting
purposes.
4. Calculations of Seasonal Performance Descriptors
4.1 Seasonal Energy Efficiency Ratio (SEER) Calculations
4.1.1 SEER calculations for an air conditioner or heat pump
having a single-speed compressor that was tested with a fixed-speed
indoor fan installed, a constant-air-volume-rate indoor fan
installed, or with no indoor fan installed
4.1.2 SEER calculations for an air conditioner or heat pump
having a single-speed compressor and a variable-speed variable-air-
volume-rate indoor fan
4.1.2.1 Units covered by Section 2.1.2.2.1 where indoor fan
capacity modulation correlates with the outdoor dry bulb temperature
4.1.2.2 Units covered by Section 2.1.2.2.2 where indoor fan
capacity modulation is used to adjust the sensible to total cooling
capacity ratio
4.1.3 SEER calculations for an air conditioner or heat pump
having a two-capacity compressor.
4.1.3.1 Steady-state space cooling capacity at low compressor
capacity is greater than or equal to the building cooling load at
temperature Tj
4.1.3.2 Unit alternates between high (k=2) and low (k=1)
compressor capacity to satisfy the building cooling load at
temperature Tj
4.1.3.3 Unit only operates at high (k=2) compressor capacity at
temperature Tj and its capacity is greater than the
building cooling load
4.1.3.4 Unit must operate continuously at high (k=2) compressor
capacity at temperature Tj
4.1.4 SEER calculations for an air conditioner or heat pump
having a variable-speed compressor
4.1.4.1 Steady-state space cooling capacity when operating at
minimum compressor speed is greater than or equal to the building
cooling load at temperature Tj
4.1.4.2 Unit operates at an intermediate compressor speed (k=i)
in order to match the building cooling load at temperature
Tj
4.1.4.3 Unit must operate continuously at maximum (k=2)
compressor speed at temperature Tj
4.2 Heating Seasonal Performance Factor (HSPF) Calculations
4.2.1 Additional steps for calculating the HSPF of a heat pump
having a single-speed compressor that was tested with a fixed-speed
indoor fan installed, a constant-air-volume-rate indoor fan
installed, or with no indoor fan installed
4.2.1.1 Space heating capacity and the electrical power
consumption calculations for a non-defrost heat pump
4.2.1.2 Space heating capacity and the electrical power
consumption calculations for a heat pump having a heat comfort
controller
4.2.2 Additional steps for calculating the HSPF of a heat pump
having a single-speed compressor and a variable-speed, variable-air-
volume-rate indoor fan.
4.2.3 Additional steps for calculating the HSPF of a heat pump
having a two-capacity compressor.
4.2.3.1 Steady-state space heating capacity when operating at
low compressor capacity is greater than or equal to the building
heating load at temperature Tj
4.2.3.2 Heat pump alternates between high (k=2) and low (k=1)
compressor capacity to satisfy the building heating load at a
temperature Tj
4.2.3.3 Heat pump only operates at high (k=2) compressor
capacity at temperature Tj and its capacity is greater
than the building heating load
4.2.3.4 Heat pump must operate continuously at high (k=2)
compressor capacity at temperature Tj
4.2.4 Additional steps for calculating the HSPF of a heat pump
having a variable-speed compressor.
4.2.4.1 Steady-state space heating capacity when operating at
minimum compressor speed is greater than or equal to the building
heating load at temperature Tj
4.2.4.2 Heat pump operates at an intermediate compressor speed
(k=i) in order to match the building heating load at a temperature
Tj
4.2.4.3 Heat pump must operate continuously at maximum (k=2)
compressor speed at temperature Tj
4.3 Calculations
4.3.1 Calculation of actual regional annual performance factors
(APFA) for a particular location and for each
standardized design heating requirement
4.3.2 Calculation of representative regional annual performance
factors (APFR) for each generalized climatic region and
for each standardized design heating requirement
4.4 Rounding of SEER , HSPF, and APF for reporting purposes
1. Definitions
1.1 Annual performance factor means the total heating and
cooling done by a heat pump in a particular region in one year
divided by the total electric energy used in one year. Section
430.23(m)(3)(iii) of the Code of Federal Regulations states the
calculation requirements for this rating descriptor.
1.2 ARI means Air-Conditioning and Refrigeration Institute.
1.3 ARI Standard 210/240-94 means the test standard ``Unitary
Air-Conditioning and Air-Source Heat Pump Equipment'' published in
1994 by ARI.
1.4 ASHRAE means the American Society of Heating, Refrigerating
and Air-Conditioning Engineers, Inc.
1.5 ASHRAE Standard 23-93 means the test standard ``Methods of
Testing for Rating Positive Displacement Refrigerant Compressors and
Condensing Units'' published in 1993 by ASHRAE.
1.6 ASHRAE Standard 37-88 means the test standard ``Methods of
Testing for Rating Unitary Air-Conditioning and Heat Pump
Equipment'' published in 1988 by ASHRAE.
1.7 ASHRAE Standard 41.1-86 (RA 91) means the test standard
``Standard Method for Temperature Measurement'' published in 1986
and reaffirmed in 1991 by ASHRAE.
1.8 ASHRAE Standard 41.2-87 (RA 92) means the test standard
``Standard Method for Laboratory Airflow Measurement'' published in
1987 and reaffirmed in 1992 by ASHRAE.
1.9 ASHRAE Standard 41.9-88 means the test standard ``A
Standard Calorimeter Test Method for Flow Measurement of a Volatile
Refrigerant'' published in 1988 by ASHRAE.
1.10 ASHRAE Standard 51-99 means the test standard ``Laboratory
Methods of Testing Fans for Rating'' published in 1999 by ASHRAE and
the Air Movement and Control Association, Inc.
1.11 ASHRAE Standard 116-95 means the test standard ``Methods
of Testing for Rating for Seasonal Efficiency of Unitary Air
Conditioners and Heat Pumps'' published in 1995 by ASHRAE.
1.12 CFR means Code of Federal Regulations.
1.13 Constant-air-volume-rate indoor fan means a fan that
varies its operating speed to provide a fixed air volume rate from a
ducted system.
1.14 Continuously recorded, when referring to a dry bulb
measurement, means that the specified temperature must be sampled at
regular intervals that are equal to or less than the maximum
intervals specified in Section 4.3 part ``a'' of ASHRAE Standard
41.1-86 (RA 91). If such dry bulb temperatures are used only for
test room
[[Page 6785]]
control, sample at regular intervals that are equal to or less than
the maximum intervals specified in Section 4.3 part ``b'' of the
same ASHRAE Standard. Regarding wet bulb temperature, dew point
temperature, or relative humidity measurements, continuously
recorded means that the measurements must be made at regular
intervals that are equal to or less than 1 minute.
1.15 Cooling load factor (CLF) means the ratio having as its
numerator the total cooling delivered during a cyclic operating
interval consisting of one ON period and one OFF period. The
denominator is the total cooling that would be delivered, given the
same ambient conditions, had the unit operated continuously at its
steady-state space cooling capacity for the same total time (ON +
OFF) interval.
1.16 Coefficient of Performance (COP) means the ratio of the
average rate of space heating delivered to the average rate of
electrical energy consumed by the heat pump. These rate quantities
must be determined from a single test or, if derived via
interpolation, must be tied to a single set of operating conditions.
COP is a dimensionless quantity. When determined for a ducted unit
tested without an indoor fan installed, COP must include the Section
3.7, 3.8, and 3.9.1 default values for the heat output and power
input of a fan motor.
1.17 Cyclic Test means a test where the unit's compressor is
cycled on and off for specific time intervals. A cyclic test
provides half the information needed to calculate a degradation
coefficient.
1.18 Damper box means a short section of duct having an air
damper that meets the performance requirements of Section 2.5.7.
1.19 Degradation coefficient (CD) means a parameter
used in calculating the part load factor. The degradation
coefficient for cooling is denoted by C\c\D. The
degradation coefficient for heating is denoted by C\h\D.
1.20 Demand-defrost control system means a system that defrosts
the heat pump outdoor coil only when measuring a predetermined
degradation of performance. The heat pump's controls monitor one or
more parameters that always vary with the amount of frost
accumulated on the outdoor coil (e.g., coil to air differential
temperature, coil differential air pressure, outdoor fan power or
current, optical sensors, etc.) at least once for every ten minutes
of compressor ON-time when space heating. One acceptable alternative
to the criterion given in the prior sentence is a feedback system
that measures the length of the defrost period and adjusts defrost
frequency accordingly.\1\ In all cases, when the frost parameter(s)
reaches a predetermined value, the system initiates a defrost. In a
demand-defrost control system, defrosts are terminated based on
monitoring a parameter(s) that indicates that frost has been
eliminated from the coil.
---------------------------------------------------------------------------
\1\ Systems that vary defrost intervals according to outdoor
dry-bulb temperature are not demand defrost systems.
---------------------------------------------------------------------------
A demand defrost control system, which otherwise meets the above
requirements, may allow time-initiated defrosts if, and only if,
such defrosts occur after 6 hours of compressor operating time.
1.21 Design heating requirement (DHR) predicts the space
heating load of a residence when subjected to outdoor design
conditions. Estimates for the minimum and maximum DHR are provided
for six generalized U.S. climatic regions in Section 4.2.
1.22 Dry-coil tests are cooling mode tests where the wet-bulb
temperature of the air supplied to the indoor coil is maintained low
enough that no condensate forms on this coil.
1.23 Ducted system means an air conditioner or heat pump that
is designed to be permanently-installed equipment and delivers
conditioned air to the indoor space through a duct(s). The air
conditioner or heat pump may be either a split system or a single-
packaged unit.
1.24 Energy efficiency ratio (EER) means the ratio of the
average rate of space cooling delivered to the average rate of
electrical energy consumed by the air conditioner or heat pump.
These rate quantities must be determined from a single test or, if
derived via interpolation, must be tied to a single set of operating
conditions. EER is expressed in units of
[GRAPHIC] [TIFF OMITTED] TP22JA01.000
.When determined for a ducted unit tested without an indoor fan
installed, EER must include the Section 3.3 and 3.5.1 default values
for the heat output and power input of a fan motor.
1.25 Heating load factor (HLF) means the ratio having as it
numerator the total heating delivered during a cyclic operating
interval consisting of one ON period and one OFF period. The
denominator is the total heating that would be delivered, given the
same ambient conditions, if the unit operated continuously at its
steady-state space heating capacity for the same total time (ON +
OFF) interval.
1.26 Heat pump having a heat comfort controller means equipment
that regulates the operation of the electric resistance elements to
assure that the air temperature leaving the indoor section does not
fall below a specified temperature. This specified temperature is
usually field adjustable. A method for testing and rating heat pumps
having a heat comfort controller is presently limited to heat pumps
that meet the equipment criteria of Section 3.6.1.
1.27 Heating seasonal performance factor (HSPF) means the total
space heating required during the space heating season, expressed in
Btu's, divided by the total electrical energy consumed by the heat
pump system during the same season, expressed in watt-hours. For all
heat pumps, HSPF accounts for the heating delivered and the energy
consumed by auxiliary resistive elements when operating below the
balance point. This condition occurs when the building load exceeds
the space heating capacity of the heat pump condenser. For heat
pumps with heat comfort controllers (see Definition 1.26), in
addition, HSPF also accounts for resistive heating contributed when
operating above the balance point as a result of maintaining a
minimum supply temperature. Unless an approved alternative rating
method is used, as set forth in 10 CFR part 430, subpart B,
Sec. 430.24(m), HSPF must be calculated according to this appendix.
Repeat the calculations for each of the six generalized U.S.
climatic regions listed in this appendix. For each region, evaluate
an HSPF for each standardized design heating requirement that
applies. (See 10 CFR part 430 subpart B, Sec. 430.23(m)(3)(ii).) The
HSPF used to evaluate compliance with the Energy Conservation
Standards (see 10 CFR part 430, subpart C, Sec. 430.32(c)) is based
on Region IV, the minimum standardized design heating requirement,
and the sampling plan stated in 10 CFR part 430, subpart B,
Sec. 430.24(m).
1.28 Mini-split air conditioners and heat pumps means non-
ducted systems that have a single outdoor section and one or more
indoor sections. The indoor sections cycle on and off in unison in
response to a single indoor thermostat.
1.29 Multiple-split air conditioners and heat pumps means non-
ducted systems that have two or more indoor sections. The indoor
sections operate independently and can be used to space condition
multiple zones in response to multiple indoor thermostats.
1.30 Non-defrost heat pumps means equipment that is incapable
of defrosting the outdoor coil. The equipment ceases to operate the
refrigeration system at outdoor temperatures that are conducive to
frost accumulation. A method for testing and rating non-defrost heat
pumps is presently limited to heat pumps that meet the equipment
criteria of Section 3.6.1.
1.31 Non-ducted system means an air conditioner or heat pump
that is designed to be permanently-installed equipment and directly
heats or cools air within the conditioned space using one or more
indoor coils that are mounted on room walls and/or ceilings. The
unit may be of a modular design that allows for combining multiple
outdoor coils and compressors to create one overall system. Non-
ducted systems covered by this test procedure are all split systems.
1.32 Part-load factor (PLF) means the ratio of the cyclic
energy efficiency ratio (coefficient of performance) to the steady-
state energy efficiency ratio (coefficient of performance). Evaluate
both energy efficiency ratios (coefficients of performance) based on
operation at the same ambient conditions.
1.33 Seasonal energy efficiency ratio (SEER) means the total
heat removed from the conditioned space during the annual space
cooling season, expressed in Btu's, divided by the total electrical
energy consumed by the air conditioner or heat pump during the same
season, expressed in watt-hours. Unless using an approved
alternative rating method, as set forth in 10 CFR part 430, subpart
B, Sec. 430.24(m), SEER must be calculated according to Section 4.1
of this appendix. [See 10 CFR part 430, subpart B, 430.23(m)(3)(i).]
This Section 4.1 SEER and the sampling plan stated in 10 CFR subpart
B, 430.24(m) are used to evaluate compliance with the Energy
Conservation Standards. (See 10 CFR part 430, subpart C,
Sec. 430.32(c).)
1.34 Single-packaged unit means any central air conditioner or
heat pump that has all major assemblies enclosed in one cabinet.
[[Page 6786]]
1.35 Split system means any air conditioner or heat pump that
has one or more of the major assemblies separated from the others.
1.36 Standard Air means dry air at 70 deg.F and 14.696 psia.
Under these conditions, dry air has a mass density of 0.075 lb/
ft.\3\
1.37 Steady-state test means a test where the test conditions
are regulated to remain as constant as possible while the unit
operates continuously in the same mode.
1.38 Temperature bin means the 5 deg.F increments that are
used to partition the outdoor dry-bulb temperature ranges of the
cooling ( 65 deg.F) and heating ( 65 deg.F) seasons.
1.39 Test condition tolerance means the maximum permissible
difference between the average value of the measured test parameter
and the specified test condition.
1.40 Test operating tolerance means the maximum permissible
range that a measurement may vary over the specified test interval.
The difference between the maximum and minimum sampled values must
be less than or equal to the specified test operating tolerance.
1.41 Time adaptive defrost control system is a demand-defrost
control system (see Definition 1.20) that measures the length of the
prior defrost period(s) and uses that information to automatically
determine when to initiate the next defrost cycle.
1.42 Time-temperature defrost control systems initiate or
evaluate initiating a defrost cycle only when a predetermined
cumulative compressor ON-time is obtained. This predetermined ON-
time is generally a fixed value (e.g., 30, 45, 90 minutes) although
it may vary based on the measured outdoor dry-bulb temperature. The
ON-time counter accumulates if controller measurements (e.g.,
outdoor temperature, evaporator temperature) indicate that frost
formation conditions are present, and it is reset/remains at zero at
all other times. In one application of the control scheme, a defrost
is initiated whenever the counter time equals the predetermined ON-
time. The counter is reset when the defrost cycle is completed. In a
second application of the control scheme, one or more parameters are
measured (e.g., air and/or refrigerant temperatures) at the
predetermined, cumulative, compressor ON-time. A defrost is
initiated only if the measured parameter(s) falls within a
predetermined range. The ON-time counter is reset regardless of
whether a defrost is initiated. If systems of this second type use
cumulative ON-time intervals of 10 minutes or less, then the heat
pump may qualify as having a demand defrost control system (see
Definition 1.20).
1.43 Triple-split system means an air conditioner or heat pump
that is composed of three separate components: An outdoor fan coil
section, an indoor fan coil section, and an indoor compressor
section.
1.44 Two-capacity (or two-stage) compressor means an air
conditioner or heat pump that has one of the following:
(1) A two-speed compressor,
(2) Two compressors where only one compressor ever operates at a
time,
(3) Two compressors where one compressor (Compressor #1)
operates at low loads and both compressors (Compressors #1 and #2)
operate at high loads but Compressor #2 never operates alone, and
(4) A compressor that is capable of cylinder or scroll
unloading.
For such systems, low capacity means:
(1) Operating at low compressor speed,
(2) Operating the lower capacity compressor,
(3) Operating Compressor #1, and
(4) Operating with the compressor unloaded (e.g., operating one
piston of a two-piston reciprocating compressor, using a fixed
fractional volume of the full scroll, etc.).
High capacity means:
(1) Operating at high compressor speed,
(2) Operating the higher capacity compressor,
(3) Operating Compressors #1 and #2, and
(4) Operating with the compressor loaded (e.g., operating both
pistons of a two-piston reciprocating compressor, using the full
volume of the scroll).
1.45 Wet-coil test means a test conducted at test conditions
that typically cause water vapor to condense on the test unit
evaporator coil.
1.46 Small-duct system means equipment that contains a blower
and indoor coil combination that produces at least 1.5 inches of
external static across the indoor unit when operated at the
certified air volume rate. When applied in the field, small-duct
systems use branch ducts having less than 6.0 square inches of free
area.
1.47 ASHRAE Standard 41.6-94 means the test standard ``Method
for Measurement of Moist Air Properties'' published in 1994 by
ASHRAE.
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2. Testing Conditions
a. This test procedure covers split-type and single-packaged
ducted units and split-type non-ducted units. Except for units
having a variable-speed compressor, ducted units tested without an
indoor fan installed are covered.
b. Only a subset of the sections listed in this test procedure
apply when testing and rating a particular unit. Tables 1-A through
1-C show which sections of the test procedure apply to each type of
equipment. In each table, look at all four of the Roman--numeral
categories to see what test sections apply to your equipment.
1. The first category, Rows I-1 through I-4 of the Tables,
pertains to the compressor and indoor fan features of the equipment.
After identifying the correct ``I'' row, find the table cells in the
same row that list the type of equipment being tested: Air
conditioner (AC), heat pump (HP), or heating-only heat pump (HH).
Use the test section(s) listed above each noted table cell for
testing and rating the unit.
2. The second category, Rows II-1 and II-2, pertains to the
presence or absence of ducts. Row II-1 shows the test procedure
sections that apply to ducted systems, and Row II-2 shows those that
apply to non-ducted systems.
3. The third category is for special features that may be
present in the equipment. When testing units that have one or more
of the four (special) equipment features described by the Table
footnote for Category III, use Row III to find test sections that
apply.
4. The fourth category is for the secondary test method to be
used. If you know the secondary method for determining the unit's
cooling and/or heating capacity, use Row IV to find the appropriate
test sections. Otherwise, include all of the test sections
referenced by Row IV cell entries--i.e., sections 2.10 to 2.10.3 and
3.11 to 3.11.3--among those sections consulted for testing and
rating information.
c. Obtain a complete listing of all pertinent test sections by
recording those sections identified from the four categories above.
d. The user should note that, for many sections, only part of a
section applies to the unit being tested. In a few cases, the entire
section may not apply. For example, Sections 3.4 to 3.5.3 (which
describe optional dry coil tests), are not relevant if the allowed
default value for the cooling mode cyclic degradation coefficient is
used rather than determining it from testing.
Example for Using Tables 1-A to 1-C.
Equipment Description:
A ducted air conditioner having a single-speed compressor, a
fixed-speed indoor fan, and a multi-speed outdoor fan.
Secondary Test Method: Refrigerant Enthalpy Method
Step 1. Determine which of four listed Row ``I'' options applies ==>
Row I-2
Table 1-A: ``AC'' in Row I-2 is found in the columns for
sections 1.1 to 1.47, 2.1 to 2.2, 2.2.4 to 2.2.4.1, 2.2.5, 2.3 to
2.3.1, 2.4 to 2.4.1, 2.5, 2.5.2 to 2.10, and 2.11 to 2.13.
Table 1-B: ``AC'' is listed in Row I-2 for sections 3 to 3.1.4,
3.1.5 to 3.1.8, 3.2.1, 3.3 to 3.5, 3.5.3, 3.11 and 3.12.
Table 1-C: ``AC'' is listed in Row I-2 for sections 4.1.1 and
4.4.
Step 2. Equipment is ducted ==> Row II-1
Table 1-A: ``AC'' is listed in Row II-1 for sections 2.4.2 and
2.5.1 to 2.5.1.2.
Table 1-B: ``AC'' is listed in Row II-1 for sections 3.1.4.1 to
3.1.4.1.1 and 3.5.1.
Table 1-C: no ``AC'' listings in Row II-1.
Step 3. Equipment Special Features include multi-speed outdoor fan
==> Row III, M
Table 1-A: ``M'' is listed in Row III for section 2.2.2
Tables 1-B and 1-C: no ``M'' listings in Row III.
Step 4. Secondary Test Method is Refrigerant Enthalpy Method ==> Row
IV, R
Table 1-A: ``R'' is listed in Row IV for section 2.10.3
Table 1-B: ``R'' is listed in Row IV for section 3.11.3
Table 1-C: no ``R'' listings in Row IV.
Step 5. Cumulative listing of applicable test procedure sections
1.1 to 1.47, 2.1 to 2.2, 2.2.2, 2.2.4 to 2.4.1, 2.2.5, 2.3 to 2.3.1,
2.4 to 2.4.1, 2.4.2, 2.5, 2.5.1 to 2.5.1.2, 2.5.2 to 2.10, 2.10.3,
2.11 to 2.13, 3. to 3.1.4, 3.1.4.1 to 3.1.4.1.1, 3.1.5 to 3.1.8,
3.2.1, 3.3 to 3.5, 3.5.1, 3.5.3, 3.11, 3.11.3, 3.12, 4.1.1, and 4.4.
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Inside these test rooms, use artificial loads during cyclic
tests and frost accumulation tests, if needed, to produce stabilized
room air temperatures. For one room, DOE recommends using an
electric resistance heater(s) having a heating capacity that is
[[Page 6792]]
approximately equal to the heating capacity of the test unit's
condenser. For the second room, DOE recommends using a heater(s)
having a capacity that is close to the sensible cooling capacity of
the test unit's evaporator. Cycle the heater located in the same
room as the test unit evaporator coil ON and OFF when the test unit
cycles ON and OFF. Cycle the heater located in the same room as the
test unit condensing coil ON and OFF when the test unit cycles OFF
and ON.
2.2 Test unit installation requirements. a. Install the unit
according to Section 8.6 of ASHRAE Standard 37-88. With respect to
interconnecting tubing used when testing split systems, however,
follow the requirements given in Section 5.1.3.5 of ARI Standard
210/240-94. When testing triple-split systems (see Definition 1.43),
use the tubing length specified in Section 5.1.3.5 of ARI Standard
210/240-94 to connect the outdoor coil, indoor compressor section,
and indoor coil while still meeting the requirement of exposing 10
feet of the tubing to outside conditions. When testing non-ducted
systems having multiple indoor coils, connect each indoor fan-coil
to the outdoor unit using: a. 25 feet of tubing, or b. tubing
furnished by the manufacturer, whichever is longer. If they are
needed to make a secondary measurement of capacity, install
refrigerant pressure measuring instruments as described in Section
8.6.5 of ASHRAE Standard 37-88. Refer to Section 2.10 of this
Appendix to learn which secondary methods require refrigerant
pressure measurements. At a minimum, insulate the low pressure
line(s) of a split system with foam insulation having an inside
diameter that matches the refrigerant tubing and a nominal thickness
of \1/2\ inch.
b. For units designed for both horizontal and vertical
installation or for both up-flow and down-flow vertical
installations, the manufacturer must specify the orientation used
for testing. Conduct testing with the following installed:
(1) The most restrictive filter(s),
(2) Supplementary heating coils, and
(3) Other equipment specified as part of the unit, including all
hardware used by a heat comfort controller if so equipped (see
Definition 1.26).
c. Testing a ducted unit without having an indoor air filter
installed is permissible as long as the minimum external static
pressure requirement is adjusted as Table 2, note 3 states (see
Section 3.1.4). Except as noted in Section 3.1.9, prevent the indoor
air supplementary heating coils from operating during all tests. For
coil only indoor units that are supplied without an enclosure,
create an enclosure using 1 inch fiberglass ductboard having a
nominal density of 6 pounds per cubic foot. Or alternatively, use
some other insulating material having a thermal resistance (``R''
value) between 4 and 6 hrft\2\ deg.F/Btu. For
units where the coil is housed within an enclosure or cabinet, no
extra insulating or sealing is allowed.
2.2.1 Defrost control settings. Set heat pump defrost controls
at the normal settings which most typify those encountered in
generalized climatic region IV. (Refer to Figure 2 and Table 17 of
Section 4.2 for information on region IV.) For heat pumps that use a
time-adaptive defrost control system (see Definition 1.41), the
manufacturer must specify the frosting interval to be used during
Frost Accumulation tests and provide the procedure for manually
initiating the defrost at the specified time. To ease testing of any
unit, the manufacturer should provide information and any necessary
hardware to manually initiate a defrost cycle.
2.2.2 Special requirements for units having a multiple-speed
outdoor fan. Configure the multiple-speed outdoor fan according to
the manufacturer's specifications, and thereafter, leave it
unchanged for all tests. The controls of the unit must regulate the
operation of the outdoor fan during all lab tests except dry coil
cooling mode tests. For dry coil cooling mode tests, the outdoor fan
must operate at the same speed as used during the required wet coil
test conducted at the same outdoor test conditions.
2.2.3 Special requirements for multi-split air conditioners and
heat pumps, and systems composed of multiple mini-split units
(outdoor units located side-by-side) that would normally operate
using two or more indoor thermostats. During the steady-state tests,
shunt all thermostats to make all indoor fan-coil units operating
simultaneously. To ease the testing burden of cyclic tests, consider
creating a single control circuit that allows simultaneous cycling
of all compressor systems. In this test procedure, references to a
single indoor fan, outdoor fan, and compressor means all indoor
fans, all outdoor fans, and all compressor systems.
2.2.4 Wet-bulb temperature requirements for the air entering
the indoor and outdoor coils.
2.2.4.1 Cooling mode tests. For wet-coil cooling mode tests,
regulate the water vapor content of the air entering the indoor unit
to the applicable wet-bulb temperature listed in Tables 3 to 6. As
noted in these same tables, achieve a wet-bulb temperature during
dry-coil cooling mode tests that results in no condensate forming on
the indoor coil. Controlling the water vapor content of the air
entering the outdoor side of the unit is not required for cooling
mode tests except when testing:
(1) Units that reject condensate to the outdoor coil during wet
coil tests. Tables 3-6 list the applicable wet-bulb temperatures.
(2) Single-packaged units where all or part of the indoor
section is located in the outdoor test room. The average dew point
temperature of the air entering the outdoor coil during wet coil
tests must be within 3.0 deg.F of the average dew point
temperature of the air entering the indoor coil over the 30-minute
data collection interval described in Section 3.3. For dry coil
tests on such units, you may need to limit the moisture content of
the air entering the outdoor side of the unit to meet the
requirements of Section 3.4.
2.2.4.2 Heating mode tests. For heating mode tests, regulate
the water vapor content of the air entering the outdoor unit to the
applicable wet-bulb temperature listed in Tables 9 to 12. The wet-
bulb temperature entering the indoor side of the heat pump must not
exceed 60 deg.F. Additionally, if you use the Outdoor Air Enthalpy
test method while testing a single-packaged heat pump where all or
part of the outdoor section is located in the indoor test room,
adjust the wet-bulb temperature for the air entering the indoor side
to yield an indoor-side dew point temperature that is as close as
reasonably possible to the dew point temperature of the outdoor-side
entering air.
2.2.5 Additional refrigerant charging requirements. Charging
according to the ``manufacturer's instructions,'' as stated in
Section 8.6 of ASHRAE Standard 37-88, means the manufacturer's
installation instructions that come packaged with the unit. For
third party testing, for example, do not consult the manufacturer
about how to charge the unit. If a unit requires charging but the
installation instructions do not specify a charging procedure, then
evacuate the unit and add the nameplate refrigerant charge. Where
the manufacturer's installation instructions contain two sets of
refrigerant charging criteria, one for field installations and one
for lab testing, use the field installation criteria.
2.3 Indoor air volume rates. If a unit's controls allow for
overspeeding the indoor fan (usually on a temporary basis), take the
necessary steps to prevent overspeeding during all tests.
2.3.1 Cooling tests. a. Set indoor fan control options (e.g.,
fan motor pin settings, fan motor speed) according to the published
installation instructions that are provided with the equipment while
meeting the airflow requirements that are specified in paragraph b.
of this section.
b. Express the Cooling Certified Air Volume Rate, the Cooling
Minimum Air Volume Rate, and the Cooling Intermediate Air Volume
Rate in terms of standard air.
2.3.2 Heating tests. a. If needed, set the indoor fan control
options (e.g., fan motor pin settings, fan motor speed) according to
the published installation instructions that are provided with the
equipment. Do this set-up while meeting all applicable airflow
requirements that are specified in paragraph b. of this section.
b. Express the Heating Certified Air Volume Rate, the Heating
Minimum Air Volume Rate, the Heating Intermediate Air Volume Rate,
and the Heating Nominal Air Volume Rate in terms of standard air.
2.4 Indoor coil inlet and outlet duct connections. Insulate
and/or construct the outlet plenum described in Section 2.4.1 and,
if installed, the inlet plenum described in Section 2.4.2 with
thermal insulation having a nominal overall resistance (R-value) of
at least 19 hrft\2\ deg.F/Btu.
2.4.1 Outlet plenum for the indoor coil. Attach a plenum to the
outlet of the indoor coil. (Note: For some packaged systems, the
indoor coil may be located in the outdoor test room.) For non-ducted
systems having multiple indoor coils, attach a plenum to each indoor
coil outlet. Add a static pressure tap to each face of the (each)
outlet plenum, if rectangular, or at four evenly distributed
locations along the circumference of an oval or round plenum. Create
a manifold that connects the four static pressure taps. Figure 1
provides recommended options for the manifold configuration. See
Figures 7 and 8 of ASHRAE Standard 37-88 for the cross-
[[Page 6793]]
sectional dimensions and minimum length of the (each) plenum and the
locations for adding the static pressure taps for units tested with
and without an indoor fan installed. For a non-ducted system having
multiple indoor coils, have all outlet plenums discharge air into a
single common duct. At the plane where each plenum enters the common
duct, install an adjustable airflow damper and use it to equalize
the static pressure in each plenum.
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2.4.2 Inlet plenum for the indoor unit. Install an inlet plenum
when testing a coil-only indoor unit or a packaged system where the
indoor coil is located in the outdoor test room. Add static pressure
taps at the center of each face of this plenum, if rectangular, or
at four evenly distributed locations along the circumference of an
oval or round plenum. Make a manifold that connects the four static
pressure taps. See Figure 8 of ASHRAE Standard 37-88 for cross-
sectional dimensions, the minimum length of the inlet plenum, and
the locations of the static pressure taps. When testing a ducted
unit having an indoor fan (and the indoor coil is in the indoor test
room), DOE recommends installing an inlet plenum if sufficient space
exists within the test room. If using an inlet plenum, add four
static pressure taps and a manifold that connects them together. DOE
recommends constructing the inlet plenum and locating the static
pressure taps as shown in Figure 8 of ASHRAE Standard 37-88. Never
use an inlet plenum when testing a non-ducted system.
2.5 Indoor coil air property measurements and air damper box
applications. a. Measure the dry-bulb temperature and water vapor
content of the air entering and leaving the indoor coil. If needed,
use an air sampling device to divert air to a sensor(s) that
measures the water vapor content of the air. See Figure 2 of ASHRAE
Standard 41.1-86 (RA 91) for guidance on constructing an air
sampling device. The sampling device may also divert air to a
remotely located sensor(s) that measures dry bulb temperature. You
may use the air sampling device and the remotely located temperature
sensor(s) to determine the entering air dry bulb temperature during
any test. You may use the air sampling device and the remotely
located leaving air dry bulb temperature sensor(s) for all tests
except:
(1) Cyclic tests, and
(2) Frost Accumulation tests.
b. An acceptable alternative in all cases, including the two
special cases noted above, is to install a grid of dry bulb
temperature sensors within the outlet and inlet ducts. Use a
temperature grid to get the average dry bulb temperature at one
location, leaving or entering, or when two grids are applied as a
thermopile, to directly obtain the temperature difference. A grid of
temperature sensors (which may also be used for determining average
leaving air dry bulb temperature) is required to measure the
temperature distribution within a cross-section of the leaving
airstream.
c. Use an inlet and outlet air damper box when testing ducted
systems if conducting one or both of the cyclic tests listed in
Sections 3.2 and 3.6 . Otherwise, DOE recommends installing an
outlet air damper box when testing heat pumps, both ducted and non-
ducted, that cycle off the indoor fan during defrost cycles. Never
use an inlet damper box when testing a non-ducted system.
2.5.1 Test set-up on the inlet side of the indoor coil: for
cases where the inlet damper box is installed. a: Install the inlet
side damper box as specified in Section 2.5.1.1 or 2.5.1.2,
whichever applies. Insulate or construct the ductwork between the
point where the air damper is installed and where the connection is
made to the following:
(1) The inlet plenum (Section 2.5.1.1 units); or
(2) To the indoor unit (Section 2.5.1.2 units) with thermal
insulation that has a nominal overall resistance (R-value) of at
least 19 hrft2 deg.F/Btu.
b. Locate the grid of entering air dry-bulb temperature sensors,
if used, at the inlet of the damper box. Locate the air sampling
device, or the sensor used to measure the water vapor content of the
inlet air, at a location immediately upstream of the damper box
inlet.
2.5.1.1 If the Section 2.4.2 inlet plenum is installed. Install
the inlet damper box upstream of the inlet plenum. The cross-
sectional flow area of the damper box must be equal to or greater
than the flow area of the inlet plenum. If needed, use an adaptor
plate or a transition duct section to connect the damper box with
the inlet plenum.
2.5.1.2 If the Section 2.4.2 inlet plenum is not installed.
Install the damper box immediately upstream of the air inlet of the
indoor unit. The cross-sectional dimensions of the damper box must
be equal to or greater than the dimensions of the indoor unit inlet.
If needed, use an adaptor plate or a short transition duct section
to connect the damper box with the unit's air inlet. Add static
pressure taps at the center of each face of the damper box, if
rectangular, or at four evenly distributed locations along the
circumference, if oval or round. Locate the pressure taps between
the inlet damper and the inlet of the indoor unit. Make a manifold
that connects the four static pressure taps.
2.5.2 Test set-up on the inlet side of the indoor unit: for
cases where no inlet damper box is installed. If using the Section
2.4.2 inlet plenum and a grid of dry bulb temperature sensors, mount
the grid at a location upstream of the static pressure taps
described in Section 2.4.2, preferably at the entrance plane of the
inlet plenum. If you do not use the Section 2.4.2 inlet plenum, but
you are using a grid of dry bulb temperature sensors, locate the
grid approximately 6 inches from the inlet of the indoor coil. Or,
in the case of non-ducted units having multiple indoor coils, locate
a grid approximately 6 inches from the inlet of each indoor coil.
Position an air sampling device, or the sensor used to measure the
water vapor content of the inlet air, immediately upstream of the
(each) entering air dry-bulb temperature sensor grid. If you are not
using a grid of sensors, position the entering air sampling device
(or the sensor used to measure the water vapor content of the inlet
air) as if the grid were present.
2.5.3 Indoor coil static pressure difference measurement.
Section 6.4.4.1 of ASHRAE Standard 37-88 describes the recommended
method for fabricating static pressure taps. Also refer to Figure 2A
of ASHRAE Standard 51-99. Use a differential pressure measuring
instrument that is accurate to within 0.01 inches of
water and has a resolution of at least 0.01 inches of water to
measure the static pressure difference between the indoor coil air
inlet and outlet. Connect one side of the differential pressure
instrument to the manifolded pressure taps installed in the outlet
plenum. Connect the other side of the instrument to the manifolded
pressure taps located in either the inlet plenum or incorporated
within the air damper box. If you are not using an inlet plenum or
inlet damper box, leave the inlet side of the differential pressure
instrument open to the surrounding atmosphere. For non-ducted
systems that are tested with multiple outlet plenums, measure the
static pressure within each outlet plenum relative to the
surrounding atmosphere.
2.5.4 Test set-up on the outlet side of the indoor coil. a:
Install an interconnecting duct between the outlet plenum described
in Section 2.4.1 and the airflow measuring apparatus described below
in Section 2.6. The cross-sectional flow area of the interconnecting
duct must be equal to or greater than the flow area of the outlet
plenum or the common duct used when testing non-ducted units having
multiple indoor coils. If needed, use adaptor plates or transition
duct sections to allow the connections. DOE recommends taping joints
within the interconnecting duct (and the outlet plenum). Construct
or insulate the entire flow section with thermal insulation having a
nominal overall resistance (R-value) of at least 19
hrft2 deg.F/Btu.
b. Install a grid(s) of dry-bulb temperature sensors inside the
interconnecting duct. Also, install an air sampling device, or the
sensor(s) used to measure the water vapor content of the outlet air,
inside the interconnecting duct. Locate the dry-bulb temperature
grid(s) upstream of the air sampling device [or the in-duct
sensor(s) used to measure the water vapor content of the outlet
air]. Air that circulates through an air sampling device and passed
a remote water-vapor-content sensor(s) must be returned to the
interconnecting duct at a point:
(1) Downstream of the air sampling device,
(2) Upstream of the outlet air damper box, if installed, and
(3) Upstream of the Section 2.6 airflow measuring apparatus.
2.5.4.1 Outlet air damper box placement and requirements. If
using an outlet air damper box (see Section 2.5), install it within
the interconnecting duct at a location downstream of the location
where air from the sampling device is reintroduced or downstream of
the in-duct sensor that measures water vapor content of the outlet
air. The leakage rate from the combination of the outlet plenum, the
closed damper, and the duct section that connects these two
components must not exceed 20 cubic feet per minute when a negative
pressure of 1 inch of water column is maintained at the plenum's
inlet.
2.5.4.2 Additional recommendations. DOE recommends installing a
mixing device(s) upstream of the outlet air, dry-bulb temperature
grid (but downstream of the outlet plenum static pressure taps).
Also, consider using a perforated screen located between the mixing
device and the dry-bulb temperature grid. DOE recommends using a
screen having a maximum open area of 40 percent. One or both items
should help to
[[Page 6796]]
meet the maximum outlet air temperature distribution specified in
Section 3.1.8. Mixing devices are described in Sections 6.3--6.5 of
ASHRAE Standard 41.1-86 (RA 91) and Section 5.2.2 of ASHRAE Standard
41.2-87 (RA 92).
2.5.5 Dry bulb temperature measurement. a. Measure dry bulb
temperatures as specified in Sections 4, 5, 6.1-6.10, 9, 10, and 11
of ASHRAE Standard 41.1-86 (RA 91). The transient testing
requirements cited in Section 4.3 of ASHRAE Standard 41.1-86 (RA 91)
apply if conducting a cyclic or Frost Accumulation test.
b. Distribute the sensors of a dry-bulb temperature grid over
the entire flow area. DOE recommends using 16 temperature sensors
within each temperature grid. The required minimum is 9 sensors per
grid. DOE recommends installing redundant inlet and outlet dry bulb
temperature sensors and particularly a thermopile. If using
thermocouples, DOE recommends the following:
(1) Use 24 gauge wire,
(2) Remove approximately 1 inch of insulation from each lead
when preparing to make a junction, and
(3) Use no more than two bonded turns per junction.
2.5.6 Water vapor content measurement. Determine water vapor
content by measuring dry-bulb temperature combined with the air wet-
bulb temperature, dew point temperature, or relative humidity. If
used, construct and apply wet-bulb temperature sensors as specified
in Sections 4, 5, 6, 9, 10, and 11 of ASHRAE Standard 41.1-86 (RA
91). As specified in ASHRAE Standard 41.1, the temperature sensor
(wick removed) must be accurate to within 0.2 deg.F. If
used, apply dew point hygrometers as specified in Sections 5 and 8
of ASHRAE Standard 41.6-94. The dew point hygrometers must be
accurate to within 0.4 deg.F when operated at
conditions that result in the evaluation of dew points above 35
deg.F. If used, a relative humidity meter must be accurate to within
0.7% RH. Other means to determine the psychrometric
state of air may be used as long as the measurement accuracy is
equivalent or better than the accuracy achieved from using a wet-
bulb temperature sensor that meets the above specifications.
2.5.7 Air damper box performance requirements. If used (see
Section 2.5), the air damper box(es) must be capable of being
completely opened or completely closed within 10 seconds for each
action.
2.6 Airflow measuring apparatus. a. Fabricate and operate an
Air Flow Measuring Apparatus as specified in Section 6.6 of ASHRAE
Standard 116-95. Refer to Figure 12 of ASHRAE Standard 51-99 or
Figure 14 of ASHRAE Standard 41.2-87 (RA 92) for guidance on placing
the static pressure taps and positioning the diffusion baffle
(settling means) relative to the chamber inlet.
b. Connect the airflow measuring apparatus to the
interconnecting duct section described in Section 2.5.4. See
Sections 6.1.1, 6.1.2, and 6.1.4, and Figures 1, 2, and 4 of ASHRAE
Standard 37-88, and Figures B1, B2, and B4 of ARI Standard 210/240-
94 for illustrative examples of how the test apparatus may be
applied within a complete laboratory set-up. Instead of following
one of these examples, you may use an alternative set-up to handle
the air leaving the airflow measuring apparatus and to supply
properly conditioned air to the test unit's inlet. The alternative
set-up, however, must not interfere with the prescribed means for
measuring airflow rate, inlet and outlet air temperatures, inlet and
outlet water vapor contents, and external static pressures, nor
create abnormal conditions surrounding the test unit. (Note: do not
use an enclosure as described in Section 6.1.3 of ASHRAE Standard
37-88 when testing triple-split units.)
2.7 Electrical voltage supply. Perform all tests at the voltage
specified in Section 5.1.3.2 of ARI Standard 210/240-94 for
``Standard Rating Tests.'' Measure the supply voltage at the
terminals on the test unit using a volt meter that provides a
reading that is accurate to within 1.0 percent of the
measured quantity.
2.8 Electrical power and energy measurements. a. Use an
integrating power (watt-hour) measuring system to determine the
electrical energy or average electrical power supplied to all
components of the air conditioner or heat pump (including auxiliary
components such as controls, transformers, crankcase heater,
integral condensate pump on non-ducted indoor units, etc.). The
watt-hour measuring system must give readings that are accurate to
within 0.5 percent. For cyclic tests, this accuracy is
required during both the ON and OFF cycles. Use either two different
scales on the same watt-hour meter or two separate watt-hour meters.
Activate the scale or meter having the lower power rating within 15
seconds after beginning an OFF cycle. Activate the scale or meter
having the higher power rating active within 15 seconds prior to
beginning an ON cycle. For ducted units tested with a fan installed,
the ON cycle lasts from compressor ON to indoor fan OFF. For ducted
units tested without an indoor fan installed, the ON cycle lasts
from compressor ON to compressor OFF. For non-ducted units, the ON
cycle lasts from indoor fan ON to indoor fan OFF. When testing air
conditioners and heat pumps having a variable-speed compressor,
avoid using an induction watt/watt-hour meter. Instead, consider
using a watt-hour measuring system that is capable of measuring up
to the 50th harmonic.
b. When performing Section 3.5 and/or 3.8 cyclic tests on non-
ducted units, provide instrumentation to determine the average
electrical power consumption of the indoor fan motor to within
1.0 percent. If required according to Sections 3.3, 3.4,
3.7, 3.9.1, and/or 3.10, this same instrumentation requirement
applies when testing air conditioners and heat pumps having a
variable-speed constant-air-volume-rate indoor fan or a variable-
speed, variable-air-volume-rate indoor fan.
2.9 Time measurements. Make elapsed time measurements using an
instrument that yields readings accurate to within 0.2
percent.
2.10 Test apparatus for the secondary space conditioning
capacity measurement. For all tests, use the Indoor Air Enthalpy
Method to measure the unit's capacity. This method uses the test
set-up specified in Sections 2.4 to 2.6. For all steady-state tests,
in addition, conduct a second, independent measurement of capacity.
For split systems, use one of the following secondary measurement
methods: Outdoor Air Enthalpy Method, Compressor Calibration Method,
or Refrigerant Enthalpy Method. Use either the Outdoor Air Enthalpy
Method or the Compressor Calibration Method as the secondary
measurement when testing a single packaged unit.
2.10.1 Outdoor Air Enthalpy Method. a. To make a secondary
measurement of indoor space conditioning capacity using the Outdoor
Air Enthalpy Method, do the following:
(1) Measure the electrical power consumption of the test unit,
(2) Measure the air-side capacity at the outdoor coil, and
(3) Apply a heat balance on the refrigerant cycle.
b. The test apparatus required for the Outdoor Air Enthalpy
Method is a subset of the apparatus used for the Indoor Air Enthalpy
Method. Required apparatus includes the following:
(1) An outlet plenum containing static pressure taps (Sections
2.4, 2.4.1, and 2.5.3),
(2) An airflow measuring apparatus (Section 2.6),
(3) A duct section that connects these two components and itself
contains the instrumentation for measuring the dry-bulb temperature
and water vapor content of the air leaving the outdoor coil
(Sections 2.5.4, 2.5.5, and 2.5.6), and
(4) On the inlet side, a sampling device and optional
temperature grid (Sections 2.5 and 2.5.2).
c. During the preliminary tests described in Sections 3.11.1 and
3.11.1.1, measure the evaporator and condenser temperatures or
pressures. On both the outdoor coil and the indoor coil, solder a
thermocouple onto a return bend located at or near the midpoint of
each coil or at points not affected by vapor superheat or liquid
subcooling. Alternatively, if the test unit is not sensitive to the
refrigerant charge, connect pressure gages to the access valves or
to ports created from tapping into the suction and discharge lines.
Use this alternative approach when testing a unit charged with a
zeotropic refrigerant having a temperature glide in excess of
1 deg.F at the specified test conditions.
2.10.2 Compressor Calibration Method. Measure refrigerant
pressures and temperatures to determine the evaporator superheat and
the enthalpy of the refrigerant that enters and exits the indoor
coil. Determine refrigerant flow rate or, when the superheat of the
refrigerant leaving the evaporator is less that 5 deg.F, total
capacity from separate calibration tests conducted under identical
operating conditions. Install instrumentation; measure refrigerant
properties; adjust the refrigerant charge according to Section 7.4.2
of ASHRAE Standard 37-88. Use refrigerant temperature and pressure
measuring instruments that meet the specifications given in Sections
5.1.1 and 5.2 of ASHRAE Standard 37-88.
2.10.3 Refrigerant Enthalpy Method. For this method, calculate
space conditioning
[[Page 6797]]
capacity by determining the refrigerant enthalpy change for the
indoor coil and directly measuring the refrigerant flow rate. Refer
to Section 7.6.2 of ASHRAE Standard 37-88 for the requirements for
using the method, the additional instrumentation requirements, and
information on placing the flow meter and a sight glass. Use
refrigerant temperature, pressure, and flow measuring instruments
that meet the specifications given in Sections 5.1.1, 5.2, and 5.5.1
of ASHRAE Standard 37-88.
2.11 Measurement of test room ambient conditions. a. If using a
test set-up where air is ducted directly from the conditioning
apparatus to the indoor coil inlet (see Figure 2, Loop Air-Enthalpy
Test Method Arrangement, of ASHRAE Standard 37-88), add
instrumentation to permit measurement of the indoor test room dry-
bulb temperature.
b. If you are not using the Outdoor Air Enthalpy Method, add
instrumentation to measure the dry-bulb temperature and the water
vapor content of the air entering the outdoor coil. DOE recommends
measuring water vapor content by using an air sampling device to
divert air to a remotely located sensor(s). If used, construct and
apply the air sampling device as per Section 6 of ASHRAE Standard
41.1-86 (RA 91). You may use the air sampling device to also divert
air to a sensor that measures outdoor-side entering dry bulb
temperature. However, DOE recommends positioning dry bulb
temperature sensors around the exterior of the entire outdoor coil
and using them to determine an average entering dry bulb
temperature. In such cases, use individually monitored sensors to
identify any significant temperature distribution. Take steps (e.g.,
add or re-position a lab circulating fan), as needed, to minimize
the magnitude of the temperature distribution. Position any fan in
the outdoor test room while trying to keep air velocities in the
vicinity of the test unit below 500 feet per minute.
c. Measure dry bulb temperatures as specified in Sections 4, 5,
6.1-6.10, 9, 10, and 11 of ASHRAE Standard 41.1-86 (RA 91). Measure
water vapor content as stated above in Section 2.5.6.
2.12 Measurement of indoor fan speed. When required, measure
fan speed using a revolution counter, tachometer, or stroboscope
that gives readings accurate to within 1.0 percent.
2.13 Measurement of barometric pressure. Determine the average
barometric pressure during each test. Use an instrument that meets
the requirements specified in Section 5.2 of ASHRAE Standard 37-88.
3. Testing Procedures
3.1 General Requirements. If during the testing process you
make an equipment set-up adjustment that would alter the performance
of the unit when conducting an already completed test, then repeat
all tests affected by the adjustment. For cyclic tests, instead of
maintaining an air volume rate, maintain the airflow nozzle(s)'
static pressure difference or velocity pressure during an ON period
at the same pressure difference or velocity pressure as measured
during the steady-state test conducted at the same test conditions.
3.1.1 Primary and secondary test methods. For all tests, use
the Indoor Air Enthalpy Method test apparatus to determine the test
unit's space conditioning capacity. The procedure and data
collected, however, differ slightly depending upon whether the test
is a steady-state test, a cyclic test, or a Frost Accumulation test.
The following sections described these differences. For all steady-
state tests (i.e., the A, A2, A1, B,
B2, B1, C, C1, EV,
F1, G1, H0, H01, H1,
H12, H11, HIN, H3, H32,
and H31 Tests), in addition, use one of the acceptable
secondary methods specified in Section 2.10 to determine indoor
space conditioning capacity. Calculate this secondary check of
capacity according to Section 3.11. The two capacity measurements
must agree to within 6 percent to constitute a valid test. For this
capacity comparison, use the Indoor Air Enthalpy Method capacity
that is calculated in Section 7.3 of ASHRAE Standard 37-88 (and do
not make the after-test fan heat adjustments described in Sections
3.3, 3.4, 3.7, and 3.10 of this Appendix). However, include the
appropriate Section 3.3 to 3.5 and 3.7 to 3.10 fan heat adjustments
within the Indoor Air Enthalpy Method capacities used for the
Section 4 seasonal calculations.
3.1.2 Manufacturer-provided equipment overrides. Where needed,
the manufacturer must provide a means for overriding the controls of
the test unit so that the compressor(s) operates at the specified
speed or capacity and the indoor fan operates at the specified speed
or delivers the specified air volume rate.
3.1.3 Airflow through the outdoor coil. For all tests, meet the
requirements given in Section 5.1.3.4 of ARI Standard 210/240-94
when obtaining the airflow through the outdoor coil.
3.1.4 Airflow through the indoor coil.
3.1.4.1 Cooling Certified Air Volume Rate.
3.1.4.1.1 Cooling Certified Air Volume Rate for Ducted Units.
The manufacturer must specify the Cooling Certified Air Volume Rate.
Use this value as long as the following two requirements are
satisfied. First, when conducting the A or A2 Test
(exclusively), the measured air volume rate, when divided by the
measured indoor air-side total cooling capacity, must not exceed
37.5 cubic feet per minute of standard air (SCFM ) per 1000 Btu/h.
If this ratio is exceeded, reduce the air volume rate until this
ratio is equaled. Use this reduced air volume rate for all tests
that call for using the Cooling Certified Air Volume Rate. The
second requirement is as follows:
a. For ducted units that are tested with a fixed-speed, multi-
speed, or variable-speed variable-air-volume-rate indoor fan
installed. For the A or A2 Test (exclusively), the
measured external static pressure must be equal to or greater than
the applicable minimum external static pressure cited in Table 2. If
the Table 2 minimum is not equaled or exceeded, incrementally change
the set-up of the indoor fan (e.g., fan motor pin settings, fan
motor speed) until the Table 2 requirement is met while maintaining
the same air volume rate. If the indoor fan set-up changes cannot
provide the minimum external static, then reduce the air volume rate
until the correct Table 2 minimum is equaled. For the last scenario,
use the reduced air volume rate for all tests that require the
Cooling Certified Air Volume Rate.
b. For ducted units that are tested with a constant-air-volume-
rate indoor fan installed. For all tests that specify the Cooling
Certified Air Volume Rate, obtain an external static pressure as
close to (but not less than) the applicable Table 2 value that does
not cause instability or an automatic shutdown of the indoor blower.
For the A or A2 Test (exclusively), the average air
volume rate from the 30-minute data collection interval (see Section
3.3) and the manufacturer-provided Cooling Certified Air Volume Rate
must differ by 8 percent or less.
c. For ducted units that are tested without an indoor fan
installed. For the A or A2 Test, (exclusively), the
pressure drop across the indoor coil assembly must not exceed a
specified maximum. The maximum value is 0.30 inches of water for all
units except small-duct, high-velocity systems (see 1.46) for which
the limit is 0.50 inches of water. If the maximum value is exceeded,
reduce the air volume rate until the measured pressure drop equals
the specified maximum. Use this reduced air volume rate for all
tests that require the Cooling Certified Air Volume Rate.
Table 2.--Minimum External Static Pressure for Ducted Systems Tested
with an Indoor Fan Installed
------------------------------------------------------------------------
Minimum
external
Rated cooling 1 or heating 2 capacity (Btu/h) resistance
3 (inches
of water)
------------------------------------------------------------------------
Up Thru 28,800............................................. 0.10
29,000 to 42,500........................................... 0.15
43,000 and Above........................................... 0.20
------------------------------------------------------------------------
1 For air conditioners and heat pumps, the value cited by the
manufacturer in published literature for the unit's capacity when
operated at the A or A2 Test conditions.
2 For heating-only heat pumps, the value the manufacturer cites in
published literature for the unit's capacity when operated at the H1
or H12 Test conditions.
3 For ducted units tested without an air filter installed, increase the
applicable tabular value by 0.08 inches of water.
3.1.4.1.2 Cooling Certified Air Volume Rate for Non-ducted
Units. For non-ducted units, the Cooling Certified Air Volume Rate
is the air volume rate that results during each test when the unit
is operated at an external static pressure of zero inches of water.
3.1.4.2 Cooling Minimum Air Volume Rate. a. For ducted units
that regulate the speed (as opposed to the CFM) of the indoor fan,
[[Page 6798]]
[GRAPHIC] [TIFF OMITTED] TP22JA01.006
where ``Cooling Minimum Fan Speed'' corresponds to the fan speed
used when operating at low compressor capacity (two-capacity
system), the fan speed used when operating at the minimum compressor
speed (variable-speed system), or the lowest fan speed used when
cooling (single-speed compressor and a variable-speed variable-air-
volume-rate indoor fan). For such systems, obtain the Cooling
Minimum Air Volume Rate regardless of the external static pressure.
b. For ducted units that regulate the air volume rate provided
by the indoor fan, the manufacturer must specify the Cooling Minimum
Air Volume Rate. For such systems, conduct all tests that specify
the Cooling Minimum Air Volume Rate--the A1,
B1, C1, F1, and G1
Tests--at an external static pressure that does not cause
instability or an automatic shutdown of the indoor blower while
being as close to, but not less than,
[GRAPHIC] [TIFF OMITTED] TP22JA01.007
where Pst, A2 is the applicable Table 2 minimum
external static pressure that was targeted during the A2
(and B2) Test. Only for the first test, the average
measured air volume rate and the manufacturer-specified Cooling
Minimum Air Volume Rate must differ by 8 percent or less.
c. For ducted two-capacity units that are tested without an
indoor fan installed, the Cooling Minimum Air Volume Rate is the
higher of the rate specified by the manufacturer or 75 percent of
the Cooling Certified Air Volume Rate. During the laboratory tests
on a coil-only (fanless) unit, obtain this Cooling Minimum Air
Volume Rate regardless of the pressure drop across the indoor coil
assembly.
d. For non-ducted units, the Cooling Minimum Air Volume Rate is
the air volume rate that results during each test when the unit
operates at an external static pressure of zero inches of water and
at the indoor fan setting used at low compressor capacity (two-
capacity system) or minimum compressor speed (variable-speed
system). For units having a single-speed compressor and a variable-
speed variable-air-volume-rate indoor fan, use the lowest fan
setting allowed for cooling.
3.1.4.3 Cooling Intermediate Air Volume Rate. a. For ducted
units that regulate the speed of the indoor fan,
[GRAPHIC] [TIFF OMITTED] TP22JA01.008
b. For such units, obtain the Cooling Intermediate Air Volume
Rate regardless of the external static pressure.
c. For ducted units that regulate the air volume rate provided
by the indoor fan, the manufacturer must specify the Cooling
Intermediate Air Volume Rate. For such systems, conduct the
EV Test at an external static pressure that does not
cause instability or an automatic shutdown of the indoor blower
while being as close to, but not less than,
[GRAPHIC] [TIFF OMITTED] TP22JA01.009
where Pst, A2 is the applicable Table 2 minimum
external static pressure that was targeted during the A2
(and B2) Test.
d. For non-ducted units, the Cooling Intermediate Air Volume
Rate is the air volume rate that results when the unit operates at
an external static pressure of zero inches of water and at the fan
speed selected by the controls of the unit for the EV
Test conditions.
3.1.4.4 Heating Certified Air Volume Rate.
3.1.4.4.1 Ducted heat pumps where the Heating and Cooling
Certified Air Volume Rates are the same.
a. Use the Cooling Certified Air Volume Rate as the Heating
Certified Air Volume Rate for:
1. Ducted heat pumps that operate at the same indoor fan speed
during both the A (or A2) and the H1 (or H12)
Tests,
2. Ducted heat pumps that regulate fan speed to deliver the same
constant air volume rate during both the A (or A2) and
the H1 (or H12) Tests, and
3. Ducted heat pumps that are tested without an indoor fan
installed (except two-capacity heat pumps that lock out high
capacity cooling--see 3.1.4.4.2).
b. For heat pumps that meet the above criteria ``1'' and ``3,''
no minimum requirements apply to the measured external or internal,
respectively, static pressure. For heat pumps that meet the above
criterion ``2,'' test at an external static pressure that does not
cause instability or an automatic shutdown of the indoor blower
while being as close to, but not less than, the same Table 2 minimum
external static pressure as was specified for the A (or
A2) cooling mode test.
3.1.4.4.2 Ducted heat pumps where the Heating and Cooling
Certified Air Volume Rates are different due to indoor fan
operation.
a. For ducted heat pumps that regulate the speed (as opposed to
the CFM) of the indoor fan,
[GRAPHIC] [TIFF OMITTED] TP22JA01.152
b. For such heat pumps, obtain the Heating Certified Air Volume
Rate without regard to the external static pressure.
c. For ducted heat pumps that regulate the air volume rate
delivered by the indoor fan, the manufacturer must specify the
Heating Certified Air Volume Rate. For such heat pumps, conduct all
tests that specify the Heating Certified Air Volume Rate at an
[[Page 6799]]
external static pressure that does not cause instability or an
automatic shutdown of the indoor blower while being as close to, but
not less than,
[GRAPHIC] [TIFF OMITTED] TP22JA01.153
where the Cooling Certified Pst is the
applicable Table 2 minimum external static pressure that was
specified for the A or A2 Test. For the first test that
uses the Heating Certified Air Volume Rate, the average measured air
volume rate and the manufacturer-specified Heating Certified Air
Volume Rate, both expressed in SCFM, must differ by 8 percent or
less.
d. When testing ducted, two-capacity heat pumps that lock out
high capacity operation when cooling, use the appropriate approach
of the above two cases for units that are tested with an indoor fan
installed. For coil-only (fanless) heat pumps that lock out high
capacity cooling, the Heating Certified Air Volume Rate is the
lesser of the rate specified by the manufacturer or 133 percent of
the Cooling Certified Air Volume Rate. For this latter case, obtain
the Heating Certified Air Volume Rate regardless of the pressure
drop across the indoor coil assembly.
3.1.4.4.3 Ducted heating-only heat pumps. This section applies
when testing ducted two-capacity heat pumps that lock out high
capacity operation when cooling. The manufacturer must specify the
Heating Certified Air Volume Rate. Use this value when the following
two requirements are satisfied. First, when conducting the H1 or
H12 Test (exclusively), the measured air volume rate,
when divided by the measured indoor air-side total heating capacity,
must not exceed 37.5 cubic feet per minute of standard air (SCFM)
per 1000 Btu/h. If this ratio is exceeded, reduce the air volume
rate until this ratio is equaled. Use this reduced air volume rate
for all tests of heating-only heat pumps that call for the Heating
Certified Air Volume Rate. The second requirement is as follows:
a. For heating-only heat pumps that are tested with a fixed-
speed, multi-speed, or variable-speed variable-air-volume-rate
indoor fan installed. For the H1 or H12 Test
(exclusively), the measured external static pressure must be equal
to or greater than the Table 2 minimum external static pressure that
applies given the heating-only heat pump's rated heating capacity.
If the Table 2 minimum is not equaled or exceeded, incrementally
change the set-up of the indoor fan until the Table 2 requirement is
met while maintaining the same air volume rate. If the indoor fan
set-up changes cannot provide the necessary external static, then
reduce the air volume rate until the correct Table 2 minimum is
equaled. For the last scenario, use the reduced air volume rate for
all tests that require the Heating Certified Air Volume Rate.
b. For ducted heating-only heat pumps having a constant-air-
volume-rate indoor fan. For all tests that specify the Heating
Certified Air Volume Rate, obtain an external static pressure that
does not cause instability or an automatic shutdown of the indoor
blower while being as close to, but not less than, the applicable
Table 2 minimum. For the H1 or H12 Test (exclusively),
the average air volume rate from the 30-minute data collection
interval (see Section 3.7) and the manufacturer-provided Heating
Certified Air Volume Rate must differ by 8 percent or less.
c. For ducted heating-only heat pumps that are tested without an
indoor fan installed. For the H1 or H12 Test,
(exclusively), the pressure drop across the indoor coil assembly
must not exceed a specified maximum. The maximum value is 0.30
inches of water for all units except small-duct, high-velocity
systems (see 1.46) for which the limit is 0.50 inches of water. If
the maximum value is exceeded, reduce the air volume rate until the
measured pressure drop equals the specified maximum. Use this
reduced air volume rate for all tests that require the Heating
Certified Air Volume Rate.
3.1.4.4.4 Non-ducted heat pumps, including non-ducted heating-
only heat pumps. For non-ducted heat pumps, the Heating Certified
Air Volume Rate is the air volume rate that results during each test
when the unit operates at an external static pressure of zero inches
of water.
3.1.4.5 Heating Minimum Air Volume Rate. a. For ducted heat
pumps that regulate the speed (as opposed to the CFM) of the indoor
fan,
[GRAPHIC] [TIFF OMITTED] TP22JA01.010
where ``Heating Minimum Fan Speed'' corresponds to the fan speed
used when operating at low compressor capacity (two-capacity
system), the lowest fan speed used at any time when operating at the
minimum compressor speed (variable-speed system), or the lowest fan
speed used when heating (single-speed compressor and a variable-
speed variable-air-volume-rate indoor fan). For such heat pumps,
obtain the Heating Minimum Air Volume Rate without regard to the
external static pressure.
b. For ducted heat pumps that regulate the air volume rate
delivered by the indoor fan, the manufacturer must specify the
Heating Minimum Air Volume Rate. For such heat pumps, conduct all
tests that specify the Heating Minimum Air Volume Rate--the
H01, H11, H21, and H31,
at an external static pressure that does not cause instability or an
automatic shutdown of the indoor blower while being as close to, but
not less than,
[GRAPHIC] [TIFF OMITTED] TP22JA01.011
where is Pst,H12 is the minimum external static
pressure that was targeted during the H12 Test. Only for
the first test, the average measured air volume rate and the
manufacturer-specified Heating Minimum Air Volume Rate must differ
by 8 percent or less.
c. When testing ducted, two-capacity heat pumps that lock out
high capacity operation when cooling, use the appropriate approach
of the above two cases for units that are tested with a indoor fan
installed.
d. For ducted two-capacity heat pumps that are tested without an
indoor fan installed, use the Cooling Minimum Air Volume Rate as the
Heating Minimum Air Volume Rate. For ducted two-capacity heat pumps
that are tested without an indoor fan installed, and that lock out
high capacity operation when cooling, use the Cooling Certified Air
Volume Rate as the Heating Minimum Air Volume Rate. For ducted two-
capacity heating-only heat pumps that are tested without an indoor
fan installed, the Heating Minimum Air Volume Rate is the higher of
the rate specified by the manufacturer or 75 percent of the Heating
Certified Air Volume Rate. During the laboratory tests on a coil-
only (fanless) unit, obtain the Heating Minimum Air Volume Rate
without regard to the pressure drop across the indoor coil assembly.
[[Page 6800]]
e. For non-ducted heat pumps, the Heating Minimum Air Volume
Rate is the air volume rate that results during each test when the
unit operates at an external static pressure of zero inches of water
and at the indoor fan setting used at low compressor capacity (two-
capacity system) or minimum compressor speed (variable-speed
system). For units having a single-speed compressor and a variable-
speed, variable-air-volume-rate indoor fan, use the lowest fan
setting allowed for heating.
3.1.4.6 Heating Intermediate Air Volume Rate. a. For ducted
heat pumps that regulate the speed of the indoor fan,
[GRAPHIC] [TIFF OMITTED] TP22JA01.012
b. For such heat pumps, obtain the Heating Intermediate Air
Volume Rate without regard to the external static pressure.
c. For ducted heat pumps that regulate the air volume rate
delivered by the indoor fan, the manufacturer must specify the
Heating Intermediate Air Volume Rate. For such heat pumps, conduct
the H2V Test at an external static pressure that does not
cause instability or an automatic shutdown of the indoor blower
while being as close to, but not less than,
[GRAPHIC] [TIFF OMITTED] TP22JA01.013
where Pst,H12 is the minimum external static
pressure that was specified for the H12 Test.
d. For non-ducted heat pumps, the Heating Intermediate Air
Volume Rate is the air volume rate that results when the heat pump
operates at an external static pressure of zero inches of water and
at the fan speed selected by the controls of the unit for the
H2V Test conditions.
3.1.4.7 Heating Nominal Air Volume Rate. Except for the noted
changes, determine the Heating Nominal Air Volume Rate using the
approach described in Section 3.1.4.6. Required changes include
substituting ``H1N Test'' for ``H2V Test''
within the first Section 3.1.4.6 equation, substituting
``H1N Test Pst`` for ``H2V
Test Pst`` in the second Section 3.1.4.6
equation, substituting ``H1N Test'' for each
``H2V Test'', and substituting ``Heating Nominal Air
Volume Rate'' for each ``Heating Intermediate Air Volume Rate.''
3.1.5 Indoor test room requirement when the air surrounding the
indoor unit is not supplied from the same source as the air entering
the indoor unit. If using a test set-up where air is ducted directly
from the air reconditioning apparatus to the indoor coil inlet (see
Figure 2, Loop Air-Enthalpy Test Method Arrangement, of ASHRAE
Standard 37-88), maintain the dry bulb temperature within the test
room within 5.0 deg.F of the applicable Sections 3.2
and 3.6 dry bulb temperature test condition for the air entering the
indoor unit.
3.1.6 Air volume rate calculations. For all steady-state tests
and for Frost Accumulation (H2, H21, H22,
H2V) Tests, calculate the air volume rate through the
indoor coil as specified in Sections 7.8.3.1 and 7.8.3.2 of ASHRAE
Standard 37-88. When using the Outdoor Air Enthalpy Method, follow
Sections 7.8.3.1 and 7.8.3.2 to calculate the air volume rate
through the outdoor coil. To express air volume rates in terms of
standard air, use:
[GRAPHIC] [TIFF OMITTED] TP22JA01.014
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.015
air volume rate of standard (dry) air, (ft3/
min)da
[GRAPHIC] [TIFF OMITTED] TP22JA01.176
air volume rate of the air-water vapor mixture, (ft3/
min)mx
[GRAPHIC] [TIFF OMITTED] TP22JA01.177
specific volume of air-water vapor mixture at the nozzle,
ft3 per lbm of the air-water vapor mixture
Wn= humidity ratio at the nozzle, lbm of water vapor per
lbm of dry air
0.075= the density associated with standard (dry) air
Vn= specific volume of the dry air portion of the mixture
evaluated at the dry-bulb temperature, vapor content, and barometric
pressure existing at the nozzle, ft3 per lbm of dry air.
3.1.7 Test sequence. When testing a ducted unit (except if a
heating-only heat pump), conduct the A or A2 Test first
to establish or verify the Cooling Certified Air Volume Rate. For
ducted heat pumps where the Heating and Cooling Certified Air Volume
Rates are different, make the first heating mode test one that
requires the Heating Certified Air Volume Rate. For ducted heating-
only heat pumps, conduct the H1 or H12 Test first to
establish or verify the Heating Certified Air Volume Rate. When
conducting an optional cyclic test, always conduct it immediately
after the steady-state test that requires the same test conditions.
For variable-speed systems, the first test using the Cooling Minimum
Air Volume Rate should precede the EV Test if you expect to adjust
the indoor fan control options when preparing for the first Minimum
Air Volume Rate test. Under the same circumstances, the first test
using the Heating Minimum Air Volume Rate should precede the
H2V Test. The test laboratory makes all other decisions
on the test sequence.
3.1.8 Requirement for the air temperature distribution leaving
the indoor coil. For at least the first cooling mode test and the
first heating mode test, monitor the temperature distribution of the
air leaving the indoor coil using the grid of individual sensors
described in Sections 2.5 and 2.5.4. For the 30-minute data
collection interval used to determine capacity, the maximum spread
among the outlet dry bulb temperatures from any data sampling must
be 1.5 deg.F or less. Install the mixing devices described in
Section 2.5.4.2 to minimize the temperature spread.
[[Page 6801]]
3.1.9 Control of auxiliary resistive heating elements. Except as
noted, disable heat pump resistance elements used for heating indoor
air at all times, including during defrost cycles and if they are
normally regulated by a heat comfort controller. For heat pumps
equipped with a heat comfort controller, enable the heat pump
resistance elements only during the below-described, short test that
follows the H1 or, if conducted, the H1C Test. Set the heat comfort
controller to provide the maximum supply air temperature. With the
heat pump operating and while maintaining the Heating Certified Air
Volume Rate, measure the temperature of the air leaving the indoor-
side beginning 5 minutes after activating the heat comfort
controller. Sample the outlet dry-bulb temperature at regular
intervals that span 5 minutes or less. Collect data for 10 minutes,
obtaining at least 3 samples. Calculate the average outlet
temperature over the 10-minute interval, TCC.
3.2 Cooling mode tests for different types of air conditioners
and heat pumps.
3.2.1 Tests for a unit having a single-speed compressor that is
tested with a fixed-speed indoor fan installed, with a constant-air-
volume-rate indoor fan installed, or with no indoor fan installed.
Conduct two steady-state wet coil tests, the A and B Tests. Use the
two optional dry-coil tests, the steady-state C Test and the cyclic
D Test, to determine the cooling mode cyclic degradation
coefficient, CcD. If the two optional tests
are not conducted, assign CcD the default
value of 0.25. Table 3 specifies test conditions for these four
tests.
Table 3.--Cooling Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed-Speed Indoor Fan,
a Constant Air Volume Rate Indoor Fan, Or No Indoor Fan
----------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor
Temperature ( deg.F) unit Temperature (
Test Description -------------------------- deg.F) Cooling Air Volume
-------------------------- Rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
A Test--required (steady, wet coil). 80 67 95 \1\ 75 Cooling Certified \2\
B Test--required (steady, wet coil). 80 67 82 \1\ 65 Cooling Certified \2\
C Test--optional (steady, dry coil). 80 \3\ 82 - Cooling Certified \2\
D Test--optional (cyclic, dry coil). 80 \3\ 82 - \4\
----------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in Section 3.1.4.1.
\3\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE
recommends using an indoor air wet-bulb temperature of 57 deg.F or less.
\4\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the
same pressure difference or velocity pressure as measured during the C Test.
3.2.2 Tests for a unit having a single-speed compressor and a
variable-speed variable-air-volume-rate indoor fan installed.
3.2.2.1 Indoor fan capacity modulation that correlates with the
outdoor dry bulb temperature. Conduct four steady-state wet coil
tests: The A2, A1, B2, and
B1 Tests. Use the two optional dry-coil tests, the
steady-state C1 Test and the cyclic D1 Test,
to determine the cooling mode cyclic degradation coefficient,
CcD. If the two optional tests are not
conducted, assign CcD the default value of
0.25. Table 4 specifies test conditions for these six tests.
3.2.2.2 Indoor fan capacity modulation based on adjusting the
sensible to total (S/T) cooling capacity ratio. The testing
requirements are the same as specified in Section 3.2.1 and Table 3.
Use a Cooling Certified Air Volume Rate that represents a normal
residential installation. If performed, conduct the steady-state C
Test and the cyclic D Test with the unit operating in the same S/T
capacity control mode as used for the B Test.
Table 4.--Cooling Mode Test Conditions for Units Having a Single-Speed Compressor and a Variable Air Volume Rate
Indoor Fan That is Controlled as Specified in 3.2.2.1
----------------------------------------------------------------------------------------------------------------
Air entering indoor Air entering outdoor
unit temperature ( unit temperature (
Test description deg.F) deg.F) Cooling air volume rate
--------------------------------------------
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
A2 Test--required (steady, wet coil).... 80 67 95 (\1\) 75 Cooling Certified \2\.
A1 Test--required (steady, wet coil).... 80 67 95 (\1\) 75 Cooling Minimum \3\.
B2 Test--required (steady, wet coil).... 80 67 82 (\1\) 65 Cooling Certified \2\.
B1 Test--required (steady, wet coil).... 80 67 82 (\1\) 65 Cooling Minimum \3\.
C1 Test \4\--optional (steady, dry coil) 80 (\4\) 82 ......... Cooling Minimum \3\.
D1 Test \4\--optional (cyclic, dry coil) 80 (\4\) 82 ......... (\5\).
----------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in Section 3.1.4.1.
\3\ Defined in Section 3.1.4.2.
\4\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE
recommends using an indoor air wet-bulb temperature of 57 deg.F or less.
\5\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the
same pressure difference or velocity pressure as measured during the C1 Test.
3.2.3 Tests for a unit having a two-capacity compressor. a.
(See Definition 1.44.) Conduct four steady-state wet coil tests: The
A2, A1, B2, and B1
Tests. Use the two optional dry-coil tests, the steady-state
C1 Test and the cyclic D1 Test, to determine
the cooling mode cyclic degradation coefficient,
CcD. If the two optional tests are not
conducted, assign CcD the default value of
0.25. Table 5 specifies test conditions for these six tests.
b. For units having a variable speed indoor fan that is
modulated to adjust the sensible to total (S/T) cooling capacity
ratio, use Cooling Certified and Cooling Minimum Air Volume Rates
that represent a normal residential installation. Additionally, if
conducting the optional dry-coil tests, operate the unit in the same
S/T capacity control mode as used for the B1 Test.
c. Two-capacity units that operate exclusively, via a lockout
feature, at low compressor capacity when space cooling must be
tested as a single speed system (see Section 3.2.1 and Table 3). If
a two-capacity
[[Page 6802]]
unit locks out low capacity operation at outdoor temperatures that
are less than 95 deg.F, conduct the A1 Test using the
outdoor temperature conditions listed for the F1 Test in
Table 6 rather than using the outdoor temperature conditions listed
in Table 5 for the A1 Test.
Table 5.--Cooling Mode Test Conditions for Units Having a Two-Capacity Compressor
----------------------------------------------------------------------------------------------------------------
Air entering indoor Air entering outdoor
unit temperature ( unit temperature (
Test description deg.F) deg.F) Compressor capacity Cooling air
-------------------------------------------- volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
A2 Test--required (steady, 80 67 95 \1\ 75 High................ Cooling
wet coil). Certified \2\.
A1 Test--required (steady, 80 67 95 \1\ 75 Low................. Cooling Minimum
wet coil). \3\.
B2 Test--required (steady, 80 67 82 \1\ 65 High................ Cooling
wet coil). Certified \2\.
B1 Test--required (steady, 80 67 82 \1\ 65 Low................. Cooling Minimum
wet coil). \3\.
C1 Test \4\--optional 80 \4\ 82 ......... Low................. Cooling Minimum
(steady, dry coil). \3\.
D1 Test \4\--optional \4\ 80 82 ......... Low \5\ ................
(cyclic, dry coil).
----------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in Section 3.1.4.1.
\3\ Defined in Section 3.1.4.2.
\4\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE
recommends using an indoor air wet-bulb temperature of 57 deg.F or less.
\5\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the
same pressure difference or velocity pressure as measured during the C1 Test.
3.2.4 Tests for a unit having a variable-speed compressor. a.
Conduct five steady-state wet coil tests: the A2,
EV, B2, B1, and F1
Tests. Use the two optional dry-coil tests, the steady-state
G1 Test and the cyclic I1 Test, to determine
the cooling mode cyclic degradation coefficient,
CDc. If the two optional tests are not
conducted, assign CDc the default value of
0.25. Table 6 specifies test conditions for these seven tests.
Determine the intermediate compressor speed cited in Table 6 using:
[GRAPHIC] [TIFF OMITTED] TP22JA01.016
where a tolerance of plus 5 percent or the next higher inverter
frequency step from that calculated is allowed.
b. For units that modulate the indoor fan speed to adjust the
sensible to total (S/T) cooling capacity ratio, use Cooling
Certified, Cooling Intermediate, and Cooling Minimum Air Volume
Rates that represent a normal residential installation.
Additionally, if conducting the optional dry-coil tests, operate the
unit in the same S/T capacity control mode as used for the
F1 Test.
Table 6.--Cooling Mode Test Conditions for Units Having a Variable-Speed Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor Air entering outdoor
unit Temperature ( unit Temperature (
Test description deg.F) deg.F) Compressor speed Cooling air volume rate
--------------------------------------------
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
A\2\ Test--required (steady, wet coil)... 80 67 95 \1\75 Maximum Cooling Certified \2\
B2 Test--required (steady, wet coil)..... 80 67 82 \1\65 Maximum Cooling Certified \2\
EV Test--required (steady, wet coil)..... 80 67 87 \1\69 Intermediate Cooling Intermediate \3\
B1 Test--required (steady, wet coil)..... 80 67 82 \1\65 Minimum Cooling Minimum \4\
F1 Test--required (steady, wet coil)..... 80 67 67 \1\53.5 Minimum Cooling Minimum \4\
G1 Test\5\--optional (steady, dry coil).. 80 \(5)\ 67 ......... Minimum Cooling Minimum \4\
I1 Test\5\--optional (cyclic, dry coil).. 80 \5\ 67 ......... Minimum \6\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in Section 3.1.4.1.
\3\ Defined in Section 3.1.4.3.
\4\ Defined in Section 3.1.4.2.
\5\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE recommends using an indoor air wet bulb
temperature of 57 deg.F or less.
\6\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity
pressure as measured during the G1 Test.
3.3 Test procedures for steady-state wet coil cooling mode
tests (the A, A2, A1, B, B2,
B1, EV, and F1 Tests). a. For the
pretest interval, operate the test room reconditioning apparatus and
the unit to be tested until maintaining equilibrium conditions for
at least 30 minutes at the specified Section 3.2 test conditions.
Use the exhaust fan of the airflow measuring apparatus and, if
installed, the indoor fan of the test unit to obtain and then
maintain the indoor air volume rate and/or external static pressure
specified for the particular test. Continuously record (see
Definition 1.14):
(1) The dry-bulb temperature of the air entering the indoor
coil,
(2) The water vapor content of the air entering the indoor coil,
(3) The dry-bulb temperature of the air entering the outdoor
coil, and
(4) For the Section 2.2.4 cases where its control is required,
the water vapor content of the air entering the outdoor coil.
[[Page 6803]]
b. Refer to Section 3.11 for additional requirements that depend
on the selected secondary test method. After satisfying the pretest
equilibrium requirements, make the measurements specified in Table 5
of ASHRAE Standard 37-88 for the Indoor Air Enthalpy method and the
user-selected secondary method. Except for external static pressure,
make the Table 5 measurements at equal intervals that span 10
minutes or less. Measure external static pressure every 5 minutes or
less. Continue data sampling until you obtain a 30-minute period
(e.g., four consecutive 10-minute samples) where the test tolerances
specified in Table 7 are satisfied. For those continuously recorded
parameters, use the entire data set from the 30-minute interval to
evaluate Table 7 compliance. Determine the average electrical power
consumption of the air conditioner or heat pump over the same 30-
minute interval.
c. Calculate indoor-side total cooling capacity as specified in
Section 7.3.3.1 of ASHRAE Standard 37-88. Do not adjust the
parameters used in calculating capacity for the permitted variations
in test conditions. Evaluate air enthalpies based on the measured
barometric pressure. Assign the average total space cooling capacity
and electrical power consumption over the 30-minute data collection
interval to the variables Qck(T) and
Eck(T), respectively. For these two variables,
replace the ``T'' with the nominal outdoor temperature at which the
test was conducted. The superscript k is used only when testing
multi-capacity units. Use the superscript k=2 to denote a test with
the unit operating at high capacity or maximum speed, k=1 to denote
low capacity or minimum speed, and k=v to denote the intermediate
speed. For units tested without an indoor fan installed, decrease
Qck(T) by
[GRAPHIC] [TIFF OMITTED] TP22JA01.017
Where
[GRAPHIC] [TIFF OMITTED] TP22JA01.018
is the average measured indoor air volume rate expressed in units of
cubic feet per minute of standard air (SCFM).
Table 7.--Test Operating and Test Condition Tolerances for Section 3.3
Steady-state Wet Coil Cooling Mode Tests and Section 3.4 Dry Coil
Cooling Mode Tests
------------------------------------------------------------------------
Test operating Test Condition
tolerance Tolerance
-----------------------------------------------(\1\)-----------(\2\)----
Indoor dry-bulb, deg.F:
Entering temperature................ 2.0 0.5
Leaving temperature................. 2.0
Indoor wet-bulb, deg.F:
Entering temperature................ 1.0 \3\ 0.3
Leaving temperature................. \3\ 1.0
Outdoor dry-bulb, deg.F:
Entering temperature................ 2.0 0.5
Leaving temperature................. \4\ 2.0
Outdoor wet-bulb, deg.F:
Entering temperature................ 1.0 \5\ 0.3
Leaving temperature................. \4\ 1.0
External resistance to airflow, inches 0.05 \6\ 0.02
of water...............................
Electrical voltage, % of rdg............ 2.0 1.5
Nozzle pressure drop, % of rdg.......... 2.0 ..............
------------------------------------------------------------------------
\1\ See Definition 1.40.
\2\ See Definition 1.39.
\3\ Only applies during wet coil tests; does not apply during steady-
state, dry coil cooling mode tests.
\4\ Only applies when using the Outdoor Air Enthalpy Method.
\5\ Only applies during wet coil cooling mode tests where the unit
rejects condensate to the outdoor coil.
\6\ Only applies when testing non-ducted units.
d. For air conditioners and heat pumps having a constant-air-
volume-rate indoor fan, the five additional steps listed below are
required if the average of the measured external static pressures
exceeds the applicable Section 3.1.4 minimum (or target) external
static pressure (Pmin) by 0.03 inches of water
or more.
1. Measure the average power consumption of the indoor fan motor
(Efan,1 ) and record the corresponding external static
pressure (P1) during or immediately following
the 30-minute interval used for determining capacity.
2. After completing the 30-minute interval and while maintaining
the same test conditions, adjust the exhaust fan of the airflow
measuring apparatus until the external static pressure increases to
approximately P1 + (P1 -
Pmin).
3. After re-establishing steady readings of the fan motor power
and external static pressure, determine average values for the
indoor fan power (Efan,2) and the external static
pressure (P2) by making measurements over a 5-
minute interval.
4. Approximate the average power consumption of the indoor fan
motor at Pmin using linear extrapolation:
[GRAPHIC] [TIFF OMITTED] TP22JA01.019
5. Increase the total space cooling capacity,
Qck(T), by the quantity (Efan,1 -
Efan,min), when expressed on a Btu/h basis. Decrease the
total electrical power, Ekc(T) , by the same
fan power difference, now expressed in watts.
3.4 Test procedures for the optional steady-state dry coil
cooling mode tests (the C, C1, and G1 Tests). a. Except
for the modifications noted in this section, conduct the steady-
state dry coil cooling mode tests as specified in Section 3.3 for
wet coil tests. Prior to recording data during the steady-state dry
coil test, operate the unit at least one hour after achieving dry
coil conditions. Drain the drain pan and plug the drain opening.
Thereafter, the drain pan should remain completely dry.
b. Denote the resulting total space cooling capacity and
electrical power derived from
[[Page 6804]]
the test as Qkss,dry(T) and
Ess,dry(T). In preparing for the Section 3.5 cyclic test,
record the average indoor-side air volume rate, V, specific heat
Cp,a of the air, (expressed on dry air basis), specific
volume of the air at the nozzle(s), vn , humidity ratio
at the nozzle(s),Wn , and either pressure difference or
velocity pressure for the flow nozzle(s). For units having a
variable-speed indoor fan (that provides either a constant or
variable air volume rate) that will or may be tested during the
cyclic dry coil cooling mode test with the indoor fan turned off
(see Section 3.5), include the electrical power used by the indoor
fan motor among the recorded parameters from the 30-minute test.
3.5 Test procedures for the optional cyclic dry coil cooling
mode tests (the D, D1, and I1 Tests). a. After
completing the steady-state dry-coil test, remove the Outdoor Air
Enthalpy method test apparatus, if connected, and begin manual OFF/
ON cycling of the unit's compressor. The test set-up should
otherwise be identical to the set-up used during the steady-state
dry coil test. When testing heat pumps, leave the switchover valve
during the compressor OFF cycles in the same position as used for
the compressor ON cycles, unless automatically changed by the
controls of the unit. For units having a variable-speed indoor fan,
the manufacturer has the option of electing at the outset whether to
conduct the cyclic test with the indoor fan enabled or disabled.
Always revert to testing with the indoor fan disabled if cyclic
testing with the fan enabled is unsuccessful.
b. For units having a single-speed or two-capacity compressor,
cycle the compressor OFF for 24 minutes and then ON for 6 minutes
(cyc,dry = 0.5 hours). For units having
a variable-speed compressor, cycle the compressor OFF for 48 minutes
and then ON for 12 minutes (cyc,dry =
1.0 hours). Repeat the OFF/ON compressor cycling pattern until you
complete the test. Allow the controls of the unit to regulate
cycling of the outdoor fan.
c. Sections 3.5.1 and 3.5.2 specify airflow requirements through
the indoor coil of ducted and non-ducted systems, respectively. In
all cases, use the exhaust fan of the airflow measuring apparatus
(covered under Section 2.6) along with the indoor fan of the unit,
if installed and operating, to approximate a step response in the
indoor coil airflow. Regulate the exhaust fan to quickly obtain and
then maintain the flow nozzle(s) static pressure difference or
velocity pressure at the same value as was measured during the
steady-state dry coil test. The pressure difference or velocity
pressure should be within 2 percent of the value from the steady-
state dry coil test within 15 seconds after airflow initiation. For
units having a variable-speed indoor fan that ramps when cycling on
and/or off, use the exhaust fan of the airflow measuring apparatus
to impose a step response that begins at the initiation of ramp up
and ends at the termination of ramp down.
d. For units having a variable-speed indoor fan, conduct the
cyclic dry coil test using a pull-thru approach if any of the
following occur when testing with the fan operating:
(1) The test unit automatically cycles off,
(2) Its blower motor reverses, or
(3) The unit operates for more than 30 seconds at a external
static pressure that is 0.1 inches of water or more higher than the
value measured during the prior steady-state test.
e. For the pull-thru approach, disable the indoor fan and use
the exhaust fan of the airflow measuring apparatus to generate the
specified flow nozzle(s) static pressure difference or velocity
pressure. If the exhaust fan cannot deliver the required pressure
difference because of resistance created by the unpowered blower,
temporarily remove the blower. After completing a minimum of two
complete compressor OFF/ON cycles, determine the overall cooling
delivered and total electrical energy consumption during any
subsequent data collection interval where the test tolerances given
in Table 8 are satisfied. DOE recommends obtaining repeatable
results for two or more data collection intervals before terminating
the test. If available, use electric resistance heaters (see Section
2.1) to minimize the variation in the inlet air temperature. With
regard to the Table 8 parameters, continuously record the dry-bulb
temperature of the air entering the indoor and outdoor coils during
periods when air flows through the respective coils. Sample the
water vapor content of the indoor coil inlet air at least every 2
minutes during periods when air flows through the coil. Record
external static pressure and the air volume rate indicator (either
nozzle pressure difference or velocity pressure) at least every
minute during the interval that air flows through the indoor coil.
(These regular measurements of the airflow rate indicator are in
addition to the required measurement at 15 seconds after flow
initiation.) Sample the electrical voltage at least every 2 minutes
beginning 30 seconds after compressor start-up. Continue until the
compressor, the outdoor fan, and the indoor fan (if it is installed
and operating) cycle off.
f. For ducted units, continuously record the dry-bulb
temperature of the air entering (as noted above) and leaving the
indoor coil. Or if using a thermopile, continuously record the
difference between these two temperatures during the interval that
air flows through the indoor coil. For non-ducted units, make the
same dry-bulb temperature measurements beginning when the compressor
cycles on and ending when indoor coil airflow ceases.
Integrate the electrical power over complete cycles of length
cyc,dry. For ducted units tested with
an indoor fan installed and operating, integrate electrical power
from indoor fan OFF to indoor fan OFF. For all other ducted units
and for non-ducted units, integrate electrical power from compressor
OFF to compressor OFF. (Some cyclic tests will use the same data
collection intervals to determine the electrical energy and the
total space cooling. For other units, you will terminate data
collection used to determine the electrical energy before you
terminate data collection used to determine total space cooling.]
Table 8.--Test Operating and Test Condition Tolerances For Cyclic Dry
Coil Cooling Mode Tests
------------------------------------------------------------------------
Test Test
operating condition
tolerance tolerance
---------------------------------------------------\1\-----------\2\----
Indoor entering dry-bulb temperature \3\, 2.0 0.5
deg.F......................................
Indoor entering wet-bulb temperature, deg.F ............ (\4\)
Outdoor entering dry-bulb temperature \3\, 2.0 0.5
deg.F......................................
External resistance to airflow \3\, inches 0.05
of water...................................
Airflow nozzle pressure difference or 2.0 \5\ 2.0
velocity pressure \3\, % of reading........
Electrical voltage (\6\), % of rdg.......... 2.0 1.5
------------------------------------------------------------------------
\1\ See Definition 1.40.
\2\ See Definition 1.39.
\3\ Applies during the interval that air flows through the indoor
(outdoor) coil except for the first 30 seconds after flow initiation.
For units having a variable-speed indoor fan that ramps, the
tolerances listed for the external resistance to airflow apply from 30
seconds after achieving full speed until ramp down begins.
\4\ Shall at no time exceed a wet-bulb temperature that results in
condensate forming on the indoor coil.
\5\ The test condition shall be the average nozzle pressure difference
or velocity pressure measured during the steady-state dry coil test.
\6\ Applies during the interval when at least one of the following--the
compressor, the outdoor fan, or, if applicable, the indoor fan--are
operating except for the first 30 seconds after compressor start-up.
g. If the Table 8 tolerances are satisfied over the complete
cycle, record the measured electrical energy consumption as
ecyc,dry and express it in units of watt-hours. Calculate
the total space cooling delivered, qcyc,dry, in units of
Btu using,
[[Page 6805]]
[GRAPHIC] [TIFF OMITTED] TP22JA01.020
where V, Cp,a, vn' (or vn), and
Wn are the values recorded during the Section 3.4 dry
coil steady-state test and,
[GRAPHIC] [TIFF OMITTED] TP22JA01.021
Ta1() = dry bulb temperature of the air entering
the indoor coil at time , deg.F.
Ta2() = dry bulb temperature of the air leaving
the indoor coil at time , deg.F.
1 = for ducted units, the elapsed time when
airflow is initiated through the indoor coil; for non-ducted units,
the elapsed time when the compressor is cycled on, hr.
2 = the elapsed time when indoor coil airflow
ceases, hr.
3.5.1 Procedures when testing ducted systems. The automatic
controls that are normally installed with the test unit must govern
the OFF/ON cycling of the air moving equipment on the indoor side
(exhaust fan of the airflow measuring apparatus and, if installed,
the indoor fan of the test unit). For example, for ducted units
tested without an indoor fan installed but rated based on using a
fan time delay relay, control the indoor coil airflow according to
the rated ON and/or OFF delays provided by the relay. For ducted
units having a variable-speed indoor fan that has been disabled (and
possibly removed), start and stop the indoor airflow at the same
instances as if the fan were enabled. For all other ducted units
tested without an indoor fan installed, cycle the indoor coil
airflow in unison with the cycling of the compressor. Close air
dampers on the inlet (Section 2.5.1) and outlet side (Sections 2.5
and 2.5.4) during the OFF period. Airflow through the indoor coil
should stop within 3 seconds after the automatic controls of the
test unit (act to) de-energize the indoor fan. For ducted units
tested without an indoor fan installed (excluding the special case
where a variable-speed fan is temporarily removed), increase
ecyc,dry by the quantity,
[GRAPHIC] [TIFF OMITTED] TP22JA01.022
where
[GRAPHIC] [TIFF OMITTED] TP22JA01.023
is the average indoor air volume rate from the Section 3.4 dry coil
steady-state test and is expressed in units of cubic feet per minute
of standard air (SCFM). For units having a variable-speed indoor fan
that is disabled during the cyclic test, increase
ecyc,dryand decrease qcyc/dry based on:
a. The product of [2 -
1] and the indoor fan power measured during or
following the dry coil steady-state test or,
b. The following algorithm if the indoor fan ramps its speed
when cycling.
1. Measure the electrical power consumed by the variable-speed
indoor fan at a minimum of three operating conditions: at the speed/
air volume rate/external static pressure that was measured during
the steady-state test, at operating conditions associated with the
midpoint of the ramp-up interval, and at conditions associated with
the midpoint of the ramp-down interval. For these measurements, the
tolerances on the airflow volume or the external static pressure are
the same as required for the Section 3.4 steady-state test.
2. For each case, determine the fan power from measurements made
over a minimum of 5 minutes.
3. Approximate the electrical energy consumption of the indoor
fan if it had operated during the cyclic test using all three power
measurements. Assume a linear profile during the ramp intervals. The
manufacturer must provide the durations of the ramp-up and ramp-down
intervals. If a manufacturer-supplied ramp interval exceeds 45
seconds, use a 45-second ramp interval nonetheless when estimating
the fan energy.
The manufacturer is allowed to choose option a, and forego the extra
testing burden of option b, even if the unit ramps indoor fan speed
when cycling.
3.5.2 Procedures when testing non-ducted systems. Do not use
air dampers when conducting cyclic tests on non-ducted units. Until
the last OFF/ON compressor cycle, airflow through the indoor coil
must cycle off and on in unison with the compressor. For the last
OFF/ON compressor cycle--the one used to determine ecyc,dry
and qcyc,dry--use the exhaust fan of the airflow
measuring apparatus and the indoor fan of the test unit to have
indoor airflow start 3 minutes prior to compressor cut-on and end
three minutes after compressor cutoff. Subtract the electrical
energy used by the indoor fan during the 3 minutes prior to
compressor cut-on from the integrated electrical energy,
ecyc,dry. Add the electrical energy used by the indoor
fan during the 3 minutes after compressor cutoff to the integrated
cooling capacity, qcyc,dry. For the case where the non-
ducted unit uses a variable-speed indoor fan which is disabled
during the cyclic test, correct ecyc,dry and
qcyc,dry using the same approach as prescribed in Section
3.5.1 for ducted units having a disabled variable-speed indoor fan.
3.5.3 Cooling mode cyclic degradation coefficient calculation.
Use two optional dry-coil tests to determine the cooling mode cyclic
degradation coefficient, CcD. If the two
optional tests are not conducted, assign CcD
the default value of 0.25. Evaluate CcD using
the above results and those from the Section 3.4 dry coil steady-
state test.0
[GRAPHIC] [TIFF OMITTED] TP22JA01.024
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.191
the average energy efficiency ratio during the cyclic dry coil
cooling mode test, Btu/Wh
[GRAPHIC] [TIFF OMITTED] TP22JA01.192
the average energy efficiency ratio during the steady-state dry coil
cooling mode test, Btu/Wh
[GRAPHIC] [TIFF OMITTED] TP22JA01.193
the cooling load factor, dimensionless.
Round the calculated value for CcD to the
nearest 0.01. If CcD is negative, then set it
equal to zero.
3.6 Heating mode tests for different types of heat pumps,
including heating-only heat pumps.
[[Page 6806]]
3.6.1 Tests for a heat pump having a single-speed compressor
that is tested with a fixed speed indoor fan installed, with a
constant-air-volume-rate indoor fan installed, or with no indoor fan
installed. Conduct three tests: the High Temperature (H1) Test, the
Frost Accumulation (H2) Test, and the Low Temperature (H3) Test.
Conduct the optional High Temperature Cyclic (H1C) Test to determine
the heating mode cyclic degradation coefficient, CDh
. If this optional test is not conducted, assign CDh
the default value of 0.25. Test conditions for these four tests are
specified in Table 9.
Table 9.--Heating Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed-Speed Indoor Fan,
a Constant Air Volume Rate Indoor Fan, Or No Indoor Fan
----------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
Temperature ( deg.F) Temperature ( deg.F) Heating air
Test description ---------------------------------------------------------------- volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
H1 Test (required, steady).... 70 60 (max) 47 43 Heating
certified \1\
H1C Test (optional, cyclic)... 70 60 (max) 47 43 \2\
H2 Test (required)............ 70 60 (max) 35 33 Heating
certified \1\
H3 Test (required, steady).... 70 60 (max) 17 15 Heating
certified \1\
----------------------------------------------------------------------------------------------------------------
\1\ Defined in Section 3.1.4.4.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the
same pressure difference or velocity pressure as measured during the H1 Test.
3.6.1.1 Non-defrost heat pump. For non-defrost heat pumps (see
Definition 1.30) that cease compressor operation at outdoor dry-bulb
temperatures less than 37 deg.F, do not conduct the H2 and H3
Tests. Instead, conduct a Maximum Temperature (H0) Test using the
Table 9 Heating Certified Air Volume Rate and the indoor and outdoor
coil air inlet conditions specified for the H01 Test in
Table 11.
3.6.1.2 Heat pump having a heat comfort controller. Test any
heat pump that has a heat comfort controller (see Definition 1.26)
according to Section 3.6.1 and Table 9 with the heat comfort
controller disabled. Additionally, conduct the abbreviated test
described in Section 3.1.9 with the heat comfort controller active
to determine the system's maximum supply air temperature.
3.6.2 Tests for a heat pump having a single-speed compressor
and a variable-speed, variable-air-volume-rate indoor fan: capacity
modulation correlates with outdoor dry bulb temperature. Conduct
five tests: two High Temperature Tests (H12 and
H11), one Frost Accumulation Test (H22), and
two Low Temperature Tests (H32 and H31).
Conducting one Frost Accumulation Test (H21), is
optional. Conduct the optional High Temperature Cyclic
(H1C1) Test to determine the heating mode cyclic
degradation coefficient, CDh If this optional
test is not conducted, assign CDh the default
value of 0.25. Table 10 specifies test conditions for these seven
tests. If you do not conduct the optional H21 Test, use
the following equations to approximate the capacity and electrical
power of the heat pump at the H21 test conditions:
[GRAPHIC] [TIFF OMITTED] TP22JA01.025
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.026
The quantities Qhk=2(47),
Ehk=2(47),
Qhk=1(47), and
Ehk=1(47) are determined from the
H12 and H11 Tests and evaluated as specified
in Section 3.7; the quantities
Qhk=2(35) and
Ehk=2(35) are determined from the
H22 Test and evaluated as specified in Section 3.9; and
the quantities Qhk=2(17),
Ehk=2(17),
Qhk=1(17), and
Ehk=1(17) are determined from the
H32 and H31 Tests and evaluated as specified
in Section 3.10.
[[Page 6807]]
Table 10.--Heating Mode Test Conditions for Units Having a Single-Speed Compressor and a Variable Air Volume
Rate Indoor Fan
----------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
Temperature ( deg.F) Temperature ( deg.F) Heating air
Test description ---------------------------------------------------------------- volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
H12 Test (required, steady)... 70 60 (max) 47 43 Heating
certified \1\
H11 Test (required, steady)... 70 60 (max) 47 43 Heating minimum
\2\
H1C1 Test (optional, cyclic).. 70 60 (max) 47 43 \3\
H22 Test (required)........... 70 60 (max) 35 33 Heating
certified \1\
H21 Test (optional)........... 70 60 (max) 35 33 Heating minimum
\2\
H32 Test (required, steady)... 70 60 (max) 17 15 Heating
certified \1\
H31 Test (required, steady)... 70 60 (max) 17 15 Heating minimum
\2\
----------------------------------------------------------------------------------------------------------------
\1\ Defined in Section 3.1.4.4.
\2\ Defined in Section 3.1.4.5.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the
same pressure difference or velocity pressure as measured during the H11 Test.
3.6.3 Tests for a heat pump having a two-capacity compressor
(see Definition 1.44).
a. Conduct one Maximum Temperature Test (H01), two
High Temperature Tests (H12 and H11), one
Frost Accumulation Test (H22), and one Low Temperature
Test (H32). Conduct an additional Frost Accumulation Test
(H2)1 and Low Temperature Test (H31) if both
of the following conditions exist:
1. You need to know the heat pump's capacity and electrical
power at low compressor capacity for outdoor temperatures of 37
deg.F and less to complete the Section 4.2.3 seasonal performance
calculations, and
2. The heat pump's controls allow low capacity operation at
outdoor temperatures of 37 deg.F and less.
b. Conduct the optional Maximum Temperature Cyclic Test
(H0C1) to determine the heating mode cyclic degradation
coefficient, CDh. If this optional test is not
conducted, assign CDh the default value of
0.25. Table 11 specifies test conditions for these eight tests.
Table 11.--Heating Mode Test Conditions for Units Having a Two-Capacity Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
Temperature ( deg.F) Temperature ( deg.F) Heating air volume
Test description ---------------------------------------------------------------- Compressor capacity rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 Test (required, steady).......... 70 60(max) 62 56.5 Low..................... Heating minimum \1\
H0C1 Test (optional, cyclic)......... 70 60(max) 62 56.5 Low..................... \2\
H12 Test (required, steady).......... 70 60(max) 47 43 High.................... Heating certified \3\
H11 Test (required, steady).......... 70 60(max) 47 43 Low..................... Heating minimum \2\
H22 Test (required).................. 70 60(max) 35 33 High.................... Heating certified \3\
H21 Test \4\ (required).............. 70 60(max) 35 33 High.................... Heating minimum \1\
H32 Test (required, steady).......... 70 60(max) 17 15 High.................... Heating certified \3\
H31 Test\4\ (required, steady)....... 70 60(max) 17 15 Low..................... Heating minimum \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in Section 3.1.4.5.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity
pressure as measured during the H01 Test.
\3\ Defined in Section 3.1.4.4.
\4\ Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37 deg.F is needed to
complete the Section 4.2.3 HSPF calculations.
3.6.4 Tests for a heat pump having a variable-speed compressor.
Conduct one Maximum Temperature Test (H01), two High
Temperature Tests (H12 and H11), one Frost
Accumulation Test (H2V), and one Low Temperature Test
(H32). Conducting one or both of the following tests is
optional: an additional High Temperature Test (H1N) and
an additional Frost Accumulation Test (H22). Conduct the
optional Maximum Temperature Cyclic (H0C1) Test to
determine the heating mode cyclic degradation coefficient,
CDh. If this optional test is not conducted,
assign CDh the default value of 0.25. Table 12
specifies test conditions for these eight tests. Determine the
intermediate compressor speed cited in Table 12 using the heating
mode maximum and minimum compressors speeds and:
[GRAPHIC] [TIFF OMITTED] TP22JA01.027
where a tolerance of plus 5 percent or the next higher inverter
frequency step from that calculated is allowed. If you do not
conduct the H22 Test, use the following equations to
approximate the capacity and electrical power at the H22
test conditions:
[GRAPHIC] [TIFF OMITTED] TP22JA01.028
[[Page 6808]]
Determine the quantities Qhk=2(47) and
Ehk=2(47) from the H12 Test and
evaluate them according to Section 3.7. Determine the quantities
Qhk=2(17) and Ehk=2(17)
from the H32 Test and evaluate them according to Section
3.10. For heat pumps where the heating mode maximum compressor speed
exceeds its cooling mode maximum compressor speed, conduct the
H1N Test if the manufacturer requests it. If you conduct
the H1N Test, operate the heat pump's compressor at the
same speed as used for the cooling mode A2 Test. Refer to
the last sentence of Section 4.2 to see how the results of the
H1N Test may be used in calculating the heating seasonal
performance factor.
Table 12.--Heating Mode Test Conditions for Units Having a Variable-Speed Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
Temperature ( deg.F) Temperature ( deg.F)
Test description ---------------------------------------------------------------- Compressor speed Heating air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 Test (required, steady).......... 70 60(max) 62 56.5 Minimum................. Heating minimum \1\
H0C1 Test (optional, cyclic)......... 70 60(max) 62 56.5 Minimum................. \2\
H12 Test (required, steady).......... 70 60(max) 47 43 Maximum................. Heating certified \3\
H11 Test (required, steady).......... 70 60(max) 47 43 Minimum................. Heating minimum \2\
H1N Test (optional, steady).......... 70 60(max) 47 43 Cooling Mode Maximum.... Heating nominal \4\
H22 Test (optional).................. 70 60(max) 35 33 Maximum................. Heating certified \3\
H2V Test (required).................. 70 60(max) 35 33 Intermediate............ Heating intermediate
\5\
H32 Test (required, steady).......... 70 60(max) 17 15 Maximum................. Heating certified \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in Section 3.1.4.5.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity
pressure as measured during the H01 Test.
\3\ Defined in Section 3.1.4.4.
\4\ Defined in Section 3.1.4.7.
\5\ Defined in Section 3.1.4.6.
3.7 Test procedures for steady-state Maximum Temperature and
High Temperature heating mode tests (the H0, H01, H1,
H12, H11, and H1N Tests). a. For
the pretest interval, operate the test room reconditioning apparatus
and the heat pump until equilibrium conditions are maintained for at
least 30 minutes at the specified Section 3.6 test conditions. Use
the exhaust fan of the airflow measuring apparatus and, if
installed, the indoor fan of the heat pump to obtain and then
maintain the indoor air volume rate and/or the external static
pressure specified for the particular test. Continuously record the
dry-bulb temperature of the air entering the indoor coil, and the
dry-bulb temperature and water vapor content of the air entering the
outdoor coil. Refer to Section 3.11 for additional requirements that
depend on the selected secondary test method. After satisfying the
pretest equilibrium requirements, make the measurements specified in
Table 5 of ASHRAE Standard 37-88 for the Indoor Air Enthalpy method
and the user-selected secondary method. Except for external static
pressure, make the Table 5 measurements at equal intervals that span
10 minutes or less. Measure external static pressure every 5 minutes
or less. Continue data sampling until you obtain a 30-minute period
(e.g., four consecutive 10-minute samples) where the test tolerances
specified in Table 13 are satisfied. For those continuously recorded
parameters, use the entire data set for the 30-minute interval when
evaluating Table 13 compliance. Determine the average electrical
power consumption of the heat pump over the same 30-minute interval.
Table 13.--Test Operating and Test Condition Tolerances for Section 3.7
and Section 3.10 Steady-State Heating Mode Tests.
------------------------------------------------------------------------
Test operating Test condition
tolerance (1) tolerance (2)
------------------------------------------------------------------------
Indoor dry-bulb, deg.F:
Entering temperature.......... 2.0 0.5
Leaving temperature........... 2.0 .................
Indoor wet-bulb, deg.F:
Entering temperature.......... 1.0 .................
Leaving temperature........... 1.0 .................
Outdoor dry-bulb, deg.F:
Entering temperature.......... 2.0 0.5
Leaving temperature........... (3) 2.0 .................
Outdoor wet-bulb, deg.F:
Entering temperature.......... 1.0 0.3
Leaving temperature........... (3) 1.0 .................
External resistance to airflow, 0.05 (4) 0.02
inches of water..................
Electrical voltage, % of rdg...... 2.0 1.5
Nozzle pressure drop, % of rdg.... 2.0 .................
------------------------------------------------------------------------
1 See Definition 1.40.
2 See Definition 1.39.
3 Only applies when the Outdoor Air Enthalpy Method is used.
4 Only applies when testing non-ducted units.
[[Page 6809]]
Calculate indoor-side total heating capacity as specified in
Section 7.3.4.1 of ASHRAE Standard 37-88. Do not adjust the
parameters used in calculating capacity for the permitted variations
in test conditions. Assign the average space heating capacity and
electrical power over the 30-minute data collection interval to the
variables and Qhk(T) and
Ehk(T), respectively. The ``T'' and
superscripted ``k'' are the same as described in Section 3.3.
Additionally, for the heating mode, use the superscript k=N to
denote results from the optional H1N Test, if conducted.
b. For heat pumps tested without an indoor fan installed,
increase Qhk(T) by
[GRAPHIC] [TIFF OMITTED] TP22JA01.029
where
[GRAPHIC] [TIFF OMITTED] TP22JA01.030
is the average measured indoor air volume rate expressed in units of
cubic feet per minute of standard air (SCFM). During the 30-minute
data collection interval of a High Temperature Test, pay attention
to preventing a defrost cycle. Prior to this time, allow the heat
pump to perform a defrost cycle if automatically initiated by its
own controls. As in all cases, wait for the heat pump's defrost
controls to automatically terminate the defrost cycle. Heat pumps
that undergo a defrost should operate in the heating mode for at
least 10 minutes after defrost termination prior to beginning the
30-minute data collection interval. For some heat pumps, frost may
accumulate on the outdoor coil during a High Temperature test. If
the indoor coil leaving air temperature or the difference between
the leaving and entering air temperatures decreases by more than 1.5
deg.F over the 30-minute data collection interval, then do not use
the collected data to determine capacity. Instead, initiate a
defrost cycle. Begin collecting data no sooner than 10 minutes after
defrost termination. Collect 30 minutes of new data during which the
Table 13 test tolerances are satisfied. In this case, use only the
results from the second 30-minute data collection interval to
evaluate Qhk(47) and
Ehk(47).
If conducting the optional cyclic heating mode test, which is
described in Section 3.8, record the average indoor-side air volume
rate,
[GRAPHIC] [TIFF OMITTED] TP22JA01.031
specific heat of the air Cp,a (expressed on dry air
basis), specific volume of the air at the nozzle(s), vn
(or vn), humidity ratio at the nozzle(s), Wn,
and either pressure difference or velocity pressure for the flow
nozzle(s). If either or both of the below criteria apply, determine
the average, steady-state, electrical power consumption of the
indoor fan motor (Efan,1).
a. the Section 3.8 cyclic test will be conducted and the heat
pump has a variable-speed indoor fan that is expected to be disabled
during the cyclic test, or
b. the heat pump has a (variable-speed) constant-air volume-rate
indoor fan and during the steady-state test the average external
static pressure (P1) exceeds the applicable
Section 3.1.4.4 minimum (or targeted) external static pressure
(Pmin) by 0.03 inches of water or more.
Determine Efan,1 by making measurements during
the 30-minute data collection interval, or immediately following the
test and prior to changing the test conditions. When the above ``b''
criteria applies, conduct the following four steps after determining
Efan,1 (which corresponds to
P1).
1. While maintaining the same test conditions, adjust the
exhaust fan of the airflow measuring apparatus until the external
static pressure increases to approximately P1 +
(P1 - Pmin).
2. After re-establishing steady readings for fan motor power and
external static pressure, determine average values for the indoor
fan power (Efan,2) and the external static
pressure (P2) by making measurements over a 5-
minute interval.
3. Approximate the average power consumption of the indoor fan
motor if the 30-minute test had been conducted at
Pmin using linear extrapolation:
[GRAPHIC] [TIFF OMITTED] TP22JA01.032
4. Decrease the total space heating capacity,
Qhk(T), by the quantity
(E)fan,1 - Efan,min,
when expressed on a Btu/h basis. Decrease the total electrical
power, E)hk (T), by the same fan power
difference, now expressed in watts.
3.8 Test procedures for the optional cyclic heating mode tests
(the H0C1, H1C, and H1C1 Tests). a. Except as
noted below, conduct the cyclic heating mode test as specified in
Section 3.5. As adapted to the heating mode, replace Section 3.5
references to ``the steady-state dry coil test'' with ``the heating
mode steady-state test conducted at the same test conditions as the
cyclic heating mode test.'' Use the test tolerances in Table 14
rather than Table 8. Record the outdoor coil entering wet-bulb
temperature according to the requirements given in Section 3.5 for
the outdoor coil entering dry-bulb temperature. Drop the subscript
``dry'' used in variables cited in Section 3.5 when referring to
quantities from the cyclic heating mode test. Determine the total
space heating delivered during the cyclic heating test,
qcyc, as specified in Section 3.5 except for making the
following changes.
(1) When evaluating Equation 3.5-1, use the values of,
[GRAPHIC] [TIFF OMITTED] TP22JA01.033
Cp,avb (or vn), and Wn
that were recorded during the Section 3.7 steady-state test
conducted at the same test conditions.
(2) Calculate using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.034
b. For ducted heat pumps tested without an indoor fan installed
(excluding the special case where a variable-speed fan is
temporarily removed), increase qcyc by the amount
calculated using Equation 3.5-3. Additionally, increase ecyc
by the amount calculated using Equation 3.5-2. In making these
calculations, use the average indoor air volume rate
[GRAPHIC] [TIFF OMITTED] TP22JA01.035
determined from the Section 3.7 steady-state heating mode test
conducted at the same test conditions.
c. For non-ducted heat pumps, subtract the electrical energy
used by the indoor fan during the 3 minutes after compressor cutoff
from the non-ducted heat pump's integrated heating capacity,
qcyc.
d. For single-speed heat pumps that defrosted before completing
the Section 3.7 H1 (or H11) steady-state test, DOE
recommends initiating a defrost cycle before cycling the heat pump
OFF and ON according to Section 3.5. Do not restrict air movement
through the indoor coil if the heat pump cycles off its indoor fan
during the defrost cycle. If conducting a defrost cycle, operate the
single-speed heat pump for at least 10 minutes after defrost
termination. After that, begin cycling the heat pump immediately or
delay until you have re-established the specified test conditions.
Pay attention to preventing defrosts after beginning the cycling
process. However, if a defrost is automatically or manually
initiated once the OFF/ON cycling begins, switch to operating the
heat pump continuously until 10 minutes after defrost termination.
After that, resume the OFF/ON cycling while conducting a minimum of
two complete compressor OFF/ON cycles before determining qcyc
and ecyc.
3.8.1 Heating mode cyclic degradation coefficient calculation.
Use the results from the optional cyclic test and the required
steady-state test that was conducted at the same test conditions to
determine the heating mode cyclic degradation coefficient,
CDh. If the optional test is not conducted,
assign CDh the default value of 0.25.
[[Page 6810]]
[GRAPHIC] [TIFF OMITTED] TP22JA01.036
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.194
the average coefficient of performance during the cyclic heating
mode test, dimensionless.
[GRAPHIC] [TIFF OMITTED] TP22JA01.195
the average coefficient of performance during the steady-state
heating mode test conducted at the same test conditions i.e., same
outdoor dry bulb temperature, Tcyc, and speed/capacity,
k, if applicable--as specified for the cyclic heating mode test,
dimensionless.
[GRAPHIC] [TIFF OMITTED] TP22JA01.196
the heating load factor, dimensionless.
Tcyc = the nominal outdoor temperature at which the
cyclic heating mode test is conducted, 62 or 47 deg.F.
cyc = the duration of the OFF/ON
intervals; 0.5 hours when testing a heat pump having a single-speed
or two-capacity compressor and 1.0 hour when testing a heat pump
having a variable-speed compressor.
Round the calculated value for ChD to the
nearest 0.01. If ChD is negative, then set it
equal to zero.
Table 14.--Test Operating and Test Condition Tolerances for Cyclic
Heating Mode Tests
------------------------------------------------------------------------
Test operating Test condition
tolerance \1\ tolerance \2\
------------------------------------------------------------------------
Indoor entering dry-bulb temperature 2.0 \3\ 0.5
\3\, deg.F........................
Indoor entering wet-bulb temperature 1.0 ................
\3\, deg.F........................
Outdoor entering dry-bulb 2.0 0.5
temperature \3\, deg.F............
Outdoor entering wet-bulb 2.0 1.0
temperature \3\, deg.F............
External resistance to air-flow \3\, 0.05 ................
inches of water....................
Airflow nozzle pressure difference 2.0 2.0 \4\
or velocity pressure \3\, % of
reading............................
Electrical voltage \5\, % of rdg.... 2.0 1.5
------------------------------------------------------------------------
\1\ See Definition 1.40.
\2\ See Definition 1.39.
\3\ Applies during the interval that air flows through the indoor
(outdoor) coil except for the first 30 seconds after flow initiation.
For units having a variable-speed indoor fan that ramps, the
tolerances listed for the external resistance to airflow shall apply
from 30 seconds after achieving full speed until ramp down begins.
\4\ The test condition shall be the average nozzle pressure difference
or velocity pressure measured during the steady-state test conducted
at the same test conditions.
\5\ Applies during the interval that at least one of the following--the
compressor, the outdoor fan, or, if applicable, the indoor fan--are
operating, except for the first 30 seconds after compressor start-up.
3.9 Test procedures for Frost Accumulation heating mode tests
(the H2, H22, H2V, and H21 Tests).
a. Confirm that the defrost controls of the heat pump are set as
specified in Section 2.2.1. Operate the test room reconditioning
apparatus and the heat pump for at least 30 minutes at the specified
Section 3.6 test conditions before starting the ``preliminary'' test
period. The preliminary test period must immediately precede the
``official'' test period, which is the heating and defrost interval
over which data are collected for evaluating average space heating
capacity and average electrical power consumption.
b. For heat pumps containing defrost controls which are likely
to cause defrosts at intervals less than one hour, the preliminary
test period starts at the termination of an automatic defrost cycle
and ends at the termination of the next occurring automatic defrost
cycle. For heat pumps containing defrost controls which are likely
to cause defrosts at intervals exceeding one hour, the preliminary
test period must consist of a heating interval lasting at least one
hour followed by a defrost cycle that is either manually or
automatically initiated. In all cases, the heat pump's own controls
must govern when a defrost cycle terminates.
c. The official test period begins when the preliminary test
period ends, at defrost termination. The official test period ends
at the termination of the next occurring automatic defrost cycle.
When testing a heat pump that uses a time-adaptive defrost control
system (see Definition 1.41), however, manually initiate the defrost
cycle that ends the official test period at the instant indicated by
instructions provided by the manufacturer. If the heat pump has not
undergone a defrost after 12 hours, immediately conclude the test
and use the results from the full 12-hour period to calculate the
average space heating capacity and average electrical power
consumption. For heat pumps that turn the indoor fan off during the
defrost cycle, take steps to cease forced airflow through the indoor
coil and block the outlet duct whenever the heat pump's controls
cycle off the indoor fan. You should use the outlet damper box
described in Section 2.5.4.1, if installed, to affect the blocked
outlet duct.
d. Defrost termination occurs when the controls of the heat pump
actuate the first change in converting from defrost operation to
normal heating operation. Defrost initiation occurs when the
controls of the heat pump first alter its normal heating operation
in order to eliminate possible accumulations of frost on the outdoor
coil.
e. To constitute a valid Frost Accumulation test, you must
satisfy the test tolerances specified in Table 15 during both the
preliminary and official test periods. As noted in Table 15, test
operating tolerances are specified for two sub-intervals: When
heating, except for the first 10 minutes after the termination of a
defrost cycle (Sub-interval H) and when defrosting, plus these same
first 10 minutes after defrost termination (Sub-interval D).
Evaluate compliance with Table 15 test condition tolerances and the
majority of the test operating tolerances using the averages from
measurements recorded only during Sub-interval H. Continuously
record the dry bulb temperature of the air entering the indoor coil,
and the dry bulb temperature and water vapor content of the air
entering the outdoor coil. Sample the remaining parameters listed in
Table 15 at equal intervals that span 10 minutes or less.
f. For the official test period, collect and use the following
data to calculate average space heating capacity and electrical
power. During heating and defrosting intervals when the controls of
the heat pump (act to) have the indoor fan on, continuously record
the dry-bulb temperature of the air entering (as noted above) and
leaving the indoor coil. If using a thermopile, continuously record
the difference between the leaving and entering dry-bulb
temperatures during the interval(s) that air flows through the
indoor coil. For heat pumps tested without an indoor fan installed,
determine the corresponding cumulative time (in hours) of indoor
coil airflow, a. Sample measurements
used in calculating the air volume rate (refer to Sections 7.8.3.1
and 7.8.3.2 of ASHRAE Standard 37-88) at equal intervals that span
10 minutes or less. Record the electrical energy consumed, expressed
in watt-hours, from defrost termination to defrost termination,
ekDEF(35), as well as the corresponding
elapsed time in hours, FR.
[[Page 6811]]
Table 15.--Test Operating and Test Condition Tolerances for Frost
Accumulation Heating Mode Tests
------------------------------------------------------------------------
Test Operating Tolerance Test
1 Condition
-------------------------- Tolerance 2
Sub- Sub- Sub-
interval H interval D interval H
----------------------------------------3------------4------------3-----
Indoor entering dry-bulb 2.0 5 4.0 0.5
temperature, deg.F.............
Indoor entering wet-bulb 1.0 ........... ...........
temperature, deg.F.............
Outdoor entering dry-bulb 2.0 10.0 1.0
temperature, deg.F.............
Outdoor entering wet-bulb 1.5 ........... 0.5
temperature, deg.F.............
External resistance to airflow, 0.05 ........... 6 0.02
inches of water.................
Electrical voltage, % of rdg..... 2.0 ........... 1.5
------------------------------------------------------------------------
1 See Definition 1.40.
2 See Definition 1.39.
3 Applies when the heat pump is in the heating mode, except for the
first 10 minutes after termination of a defrost cycle.
4 Applies during a defrost cycle and during the first 10 minutes after
the termination of a defrost cycle when the heat pump is operating in
the heating mode.
5 For heat pumps that turn off the indoor fan during the defrost cycle,
the noted tolerance only applies during the 10 minute interval that
follows defrost termination.
6 Only applies when testing non-ducted heat pumps.
3.9.1 Average space heating capacity and electrical power
calculations. Evaluate average space heating capacity,
Qhk(35), when expressed in units of Btu per
hour, using:
[GRAPHIC] [TIFF OMITTED] TP22JA01.037
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.038
the average indoor air volume rate measured during Sub-interval H,
cfm.
Cp,a = 0.24 + 0.444 Wn, the
constant pressure specific heat of the air-water vapor mixture that
flows through the indoor coil and is expressed on a dry air basis,
Btu / lbmda deg.F.
Vn = specific volume of the air-water vapor mixture at
the nozzle, ft\3\ / lbmmx.
Wn = humidity ratio of the air-water vapor mixture at the
nozzle, lbm of water vapor per lbm of dry air.
FR = 2 -
1, the elapsed time from defrost termination to
defrost termination, hr.
[GRAPHIC] [TIFF OMITTED] TP22JA01.039
Tal()= dry bulb temperature of the air entering
the indoor coil at elapsed time , deg.F; only recorded
when indoor coil airflow occurs; assigned the value of zero during
periods (if any) where the indoor fan cycles off.
Ta2()= dry bulb temperature of the air leaving
the indoor coil at elapsed time , deg.F; only recorded
when indoor coil airflow occurs; assigned the value of zero during
periods (if any) where the indoor fan cycles off.
1 = the elapsed time when the defrost
termination occurs that begins the official test period, hr.
2 = the elapsed time when the next automatically
occurring defrost termination occurs, thus ending the official test
period, hr
Vn = specific volume of the dry air portion of the
mixture evaluated at the dry-bulb temperature, vapor content, and
barometric pressure existing at the nozzle, ft \3\ per lbm of dry
air.
Evaluate average electrical power,
Ekh(35), when expressed in units of watts,
using:
[GRAPHIC] [TIFF OMITTED] TP22JA01.040
For heat pumps tested without an indoor fan installed, increase
Qkh(35) by,
[GRAPHIC] [TIFF OMITTED] TP22JA01.041
and increase Ekh(35) by,
[GRAPHIC] [TIFF OMITTED] TP22JA01.042
where Vs is the average indoor air volume rate measured
during the Frost Accumulation heating mode test and is expressed in
units of cubic feet per minute of standard air (SCFM). For heat
pumps having a constant-air-volume-rate indoor fan, the five
additional steps listed below are required if the average of the
measured external static pressures exceeds the Section 3.1.4.4
minimum (or targeted) external static pressure
(Pmin) by 0.03 inches of water or more.
1. Measure the average power consumption of the indoor fan motor
(Efan, 1) and record the corresponding
external static pressure (P1) during or
immediately following the 30-minute interval used for determining
capacity.
2. After the 30-minute interval is completed and while
maintaining the same test conditions, adjust the exhaust fan of the
airflow measuring apparatus until the external static pressure
increases to approximately P1 +
(P1 - Pmin).
3. After re-establishing steady readings for the fan motor power
and external static pressure, determine average values for the
indoor fan power (Efan, 2) and the external
static pressure (P2) by making measurements over
a 5-minute interval.
4. Approximate the average power consumption of the indoor fan
motor had the 30-minute tests been conducted at
Pmin using linear extrapolation:
[GRAPHIC] [TIFF OMITTED] TP22JA01.044
5. Increase the total heating capacity,
Qhk(35), by the quantity
[(Efan,1 - Efan,min)
(a /
a FR)], when expressed on a Btu/h
basis. Decrease the total electrical power,
Ekh(35), by the same quantity, now expressed
in watts.
3.9.2 Demand defrost credit. Assign the demand defrost credit,
Fdef, that is used in Section 4.2 to the value of 1 in
all cases
[[Page 6812]]
except for heat pumps having a demand-defrost control system
(Definition 1.20). For such qualifying heat pumps, evaluate
Fdef using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.045
where,
def = the time between defrost
terminations (in hours) or 1.5, whichever is greater.
max = maximum time between defrosts as
allowed by the controls (in hours) or 12, whichever is less.
For two-capacity heat pumps and for Section 3.6.2 units,
evaluate the above equation using the def
that applies based on the Frost Accumulation Test conducted at high
capacity and/or at the Heating Certified Air Volume Rate. For
variable-speed heat pumps, evaluate def
based on the required Frost Accumulation Test conducted at the
intermediate compressor speed.
3.10 Test procedures for steady-state Low Temperature heating
mode tests (the H3, H32, and H31 Tests).
Except for the modifications noted in this section, conduct the Low
Temperature heating mode test using the same approach as specified
in Section 3.7 for the Maximum and High Temperature tests. After
satisfying the Section 3.7 requirements for the pretest interval but
before you begin collecting data to determine
Qhk(17) and Ehk(17),
conduct a defrost cycle. This defrost cycle may be manually or
automatically initiated. The defrost sequence must be terminated by
the action of the heat pump's defrost controls. Begin the 30-minute
data collection interval described in Section 3.7, from which
Qhk(17) and Ehk(17) are
determined, no sooner than 10 minutes after defrost termination.
Defrosts should be prevented over the 30-minute data collection
interval.
3.11 Additional requirements for the secondary test methods.
Prior to evaluating if the energy balance specified in Section 3.1.1
is obtained, you should make an adjustment to account for the energy
loss within the air duct that connects the indoor coil and the
location where the outlet dry-bulb temperature is measured. If using
the Outdoor Air Enthalpy Method, you should make an adjustment to
account for the energy loss within the air duct that connects the
outdoor coil and the location where the outlet temperature is
measured. In all cases, apply the correction to the indoor space
conditioning capacity that is determined using the secondary test
method.
3.11.1 If using the Outdoor Air Enthalpy Method as the secondary
test method. During the ``official'' test, the outdoor air-side test
apparatus described in Section 2.10.1 is connected to the outdoor
unit. To help compensate for any effect that the addition of this
test apparatus may have on the unit's performance, conduct a
``preliminary'' test where the outdoor air-side test apparatus is
disconnected. Conduct a preliminary test prior to the first Section
3.2 steady-state cooling mode test and prior to the first Section
3.6 steady-state heating mode test. No other preliminary tests are
required so long as the unit operates the outdoor fan during all
cooling mode steady-state tests at the same speed and all heating
mode steady-state tests at the same speed. If using more than one
outdoor fan speed for the cooling mode steady-state tests, however,
conduct a preliminary test prior to each cooling mode test where a
different fan speed is first used. This same requirement applies for
the heating mode tests.
3.11.1.1 If a preliminary test precedes the official test. The
test conditions for the preliminary test are the same as specified
for the official test. Connect the indoor air-side test apparatus to
the indoor coil; disconnect the outdoor air-side test apparatus.
Allow the test room reconditioning apparatus and the unit being
tested to operate for at least one hour. After attaining equilibrium
conditions, measure the following quantities at equal intervals that
span 10 minutes or less:
1. The Section 2.10.1 evaporator and condenser temperatures or
pressures
2. Parameters required according to the Indoor Air Enthalpy
Method.
Continue these measurements until a 30-minute period (e.g., four
consecutive 10-minute samples) is obtained where the Table 7 or
Table 13, whichever applies, test tolerances are satisfied. After
collecting 30 minutes of steady-state data, reconnect the outdoor
air-side test apparatus to the unit. Adjust the exhaust fan of the
outdoor airflow measuring apparatus until averages for the
evaporator and condenser temperatures, or the saturated temperatures
corresponding to the measured pressures, agree within
0.5 deg.F of the averages achieved when the outdoor
air-side test apparatus was disconnected. Calculate the averages for
the reconnected case using five or more consecutive readings taken
at one minute intervals. Make these consecutive readings after re-
establishing equilibrium conditions and before initiating the
official test.
3.11.1.2 If a preliminary test does not precede the official
test. Connect the outdoor-side test apparatus to the unit. Adjust
the exhaust fan of the outdoor airflow measuring apparatus to
achieve the same external static pressure as measured during the
prior preliminary test conducted with the unit operating in the same
cooling or heating mode at the same outdoor fan speed.
3.11.1.3 Official test. a. Continue (preliminary test was
conducted) or begin (no preliminary test) the official test by
making measurements for both the Indoor and Outdoor Air Enthalpy
Methods at equal intervals that span 10 minutes or less. Discontinue
these measurement only after obtaining a 30-minute period where the
specified test condition and test operating tolerances are
satisfied. To constitute a valid official test,
(1) Achieve the energy balance specified in Section 3.1.1 and,
(2) For cases where you conduct a preliminary test, the
capacities determined using the Indoor Air Enthalpy Method from the
official and preliminary test periods must agree within 2.0 percent.
b. For space cooling tests, calculate capacity from the outdoor
air enthalpy measurements as specified in Section 7.3.3.2 of ASHRAE
Standard 37-88. Calculate heating capacity based on outdoor air
enthalpy measurements as specified in Section 7.3.4.2 of the same
ASHRAE Standard. You may adjust outdoor side capacities according to
Section 7.3.3.3 of ASHRAE Standard 37-88 to account for line losses
when testing split systems. Do not correct the average electrical
power measurement as described in Section 8.5.3 of ASHRAE Standard
37-88.
3.11.2 If using the Compressor Calibration Method as the
secondary test method. a. Conduct separate calibration tests using a
calorimeter to determine the refrigerant flow rate. Or for cases
where the superheat of the refrigerant leaving the evaporator is
less than 5 deg.F, use the calorimeter to measure total capacity
rather than refrigerant flow rate. Conduct these calibration tests
at the same test conditions as specified for the tests in this
Appendix. Operate the unit for at least one hour or until obtaining
equilibrium conditions before collecting data that will be used in
determining the average refrigerant flow rate or total capacity.
Sample the data at equal intervals that span 10 minutes or less.
Determine average flow rate or average capacity from data sampled
over a 30-minute period where the Table 7 (cooling) or the Table 13
(heating) tolerances are satisfied. Otherwise, conduct the
calibration tests according to ASHRAE Standard 23-93, ASHRAE
Standard 41.9-88, and Section 7.5 of ASHRAE Standard 37-88.
b. Calculate space cooling and space heating capacities using
the compressor calibration method measurements as specified in
Sections 7.5.7 and 7.5.8, respectively, of ASHRAE Standard 37-88.
3.11.3 If using the Refrigerant Enthalpy Method as the
secondary test method. Conduct this secondary method according to
Section 7.6 of ASHRAE Standard 37-88. Calculate space cooling and
space heating capacities using the refrigerant enthalpy method
measurements as specified in Sections 7.6.4 and 7.6.5, respectively,
of the same ASHRAE Standard.
3.12 Rounding of space conditioning capacities for reporting
purposes. When reporting rated capacities, round them off as
follows.
1. For capacities less than 20,000 Btu/h, round to the nearest
100 Btu/h.
2. For capacities between 20,000 and 37,999 Btu/h, round to the
nearest 200 Btu/h.
3. For capacities between 38,000 and 64,999 Btu/h, round to the
nearest 500 Btu/h.
For the capacities used to perform the Section 4 calculations,
however, round only to the nearest integer.
4. Calculations of Seasonal Performance Descriptors
4.1 Seasonal Energy Efficiency Ratio (SEER) Calculations. For
equipment covered under Sections 4.1.2, 4.1.3, and 4.1.4, evaluate
the seasonal energy efficiency ratio,
[GRAPHIC] [TIFF OMITTED] TP22JA01.046
[[Page 6813]]
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.186
the ratio of the total space cooling provided during periods of the
space cooling season when the outdoor temperature fell within the
range represented by bin temperature Tj to the total
number of hours in the cooling season (N), Btu/h.
[GRAPHIC] [TIFF OMITTED] TP22JA01.187
the electrical energy consumed by the test unit during periods of
the space cooling season when the outdoor temperature fell within
the range represented by bin temperature Tj to the total
number of hours in the cooling season (N), W.
Tj = the outdoor bin temperature, deg.F. Outdoor
temperatures are grouped or ``binned.'' Use bins of 5 deg.F with
the 8 cooling season bin temperatures being 67, 72, 77, 82, 87, 92,
97, and 102 deg.F.
j = the bin number. For cooling season calculations,
j ranges from 1 to 8.
Additionally, for Sections 4.1.2, 4.1.3, and 4.1.4, use a
building cooling load, BL(Tj). When referenced, evaluate
BL(Tj) for cooling using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.047
where,
Qck=\2\(95) = the space cooling capacity
determined from the A2 Test and calculated as specified
in Section 3.3, Btu/h.
1.1 = sizing factor, dimensionless.
The temperatures 95 deg.F and 65 deg.F in the building load
equation represent the selected outdoor design temperature and the
zero-load base temperature, respectively.
4.1.1 SEER calculations for an air conditioner or heat pump
having a single-speed compressor that was tested with a fixed-speed
indoor fan installed, a constant-air-volume-rate indoor fan
installed, or with no indoor fan installed. a. Evaluate the seasonal
energy efficiency ratio, expressed in units of Btu/watt-hour, using:
[GRAPHIC] [TIFF OMITTED] TP22JA01.048
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.049
the energy efficiency ratio determined from the B Test described in
Sections 3.2.1, 3.1.4.1, and 3.3, Btu/h per watt.
PLF(0.5) = 1 - 0.5 CcD, the
part-load performance factor evaluated at a cooling load factor of
0.5, dimensionless.
b. Refer to Section 3.3 regarding the definition and calculation
of Qc(82) and Ec(82). If the optional tests
described in Section 3.2.1 are not conducted, set the cooling mode
cyclic degradation coefficient, QDc, to the
default value specified in Section 3.5.3. If these optional tests
are conducted, set Qcd to the lower of:
1. The value calculated as per Section 3.5.3 or
2. The Section 3.5.3 default value of 0.25.
4.1.2 SEER calculations for an air conditioner or heat pump
having a single-speed compressor and a variable-speed variable-air-
volume-rate indoor fan.
4.1.2.1 Units covered by Section 3.2.2.1 where indoor fan
capacity modulation correlates with the outdoor dry bulb
temperature. The manufacturer must provide information on how the
indoor air volume rate or the indoor fan speed varies over the
outdoor temperature range of 67 deg.F to 102 deg.F.
Calculate SEER using Equation 5.4-1. Evaluate the quantity
[GRAPHIC] [TIFF OMITTED] TP22JA01.050
in Equation 4.1-1 using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.051
where
[GRAPHIC] [TIFF OMITTED] TP22JA01.188
the cooling mode load factor for temperature bin j,
dimensionless.
Qc(Tj) = the space cooling capacity of the
test unit when operating at outdoor temperature, Tj, Btu/
h.
[GRAPHIC] [TIFF OMITTED] TP22JA01.052
fractional bin hours for the cooling season; the ratio of the number
of hours during the cooling season when the outdoor temperature fell
within the range represented by bin temperature Tj to the
total number of hours in the cooling season, dimensionless.
a. For the space cooling season, assign
[GRAPHIC] [TIFF OMITTED] TP22JA01.053
as specified in Table 16. Use Equation 4.1-2 to calculate the
building load, BL(Tj). Evaluate
QC(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.054
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.055
the space cooling capacity of the test unit at outdoor temperature
Tj if operated at the Cooling Minimum Air Volume Rate,
Btu/h.
[[Page 6814]]
[GRAPHIC] [TIFF OMITTED] TP22JA01.189
the space cooling capacity of the test unit at outdoor temperature
Tj if operated at the Cooling Certified Air Volume Rate,
Btu/h.
b. For units where indoor fan speed is the primary control
variable, FPck=1denotes the fan speed used
during the required A1 and B1 Tests (see
Section 3.2.2.1), FPck=2 denotes the fan speed
used during the required A2 and B2 Tests, and
FPc(Tj) denotes the fan speed used by the unit
when the outdoor temperature equals Tj. For units where
indoor air volume rate is the primary control variable, the three
FPc's are similarly defined only now being expressed in
terms of air volume rates rather than fan speeds. Refer to Sections
3.2.2.1, 3.1.4 to 3.1.4.2, and 3.3 regarding the definitions and
calculations of Qck=\1\(82),
Qck=\1\(95),
Qck=\2\(82), and
Qck=\2\(95).
Calculate
[GRAPHIC] [TIFF OMITTED] TP22JA01.056
in Equation 4.1 using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.057
where,
PLFj = 1 - CDc [1 - X
(Tj), the part load factor, dimensionless.
Ec(Tj) = the electrical power consumption of
the test unit when operating at outdoor temperature Tj,
W.
The quantities X(Tj) and nj/N are the same
quantities as used in Equation 4.1.2-1. If the optional tests
described in Section 3.2.2.1 and Table 4 are not conducted, set the
cooling mode cyclic degradation coefficient,
CDc, to the default value specified in Section
3.5.3. If these optional tests are conducted, set
CDc to the lower of
a. The value calculated as per Section 3.5.3 or
b. The Section 3.5.3 default value of 0.25.
Evaluate E(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.058
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.059
the electrical power consumption of the test unit at outdoor
temperature Tj if operated at the Cooling Minimum Air
Volume Rate, W.
[GRAPHIC] [TIFF OMITTED] TP22JA01.190
the electrical power consumption of the test unit at outdoor
temperature Tj if operated at the Cooling Certified Air
Volume Rate, W.
The parameters FPck=\1\,
FPck=\2\, and FPc (Tj)
are the same quantities that are used when evaluating Equation
4.1.2-2. Refer to Sections 3.2.2.1, 3.1.4 to 3.1.4.2, and 3.3
regarding the definitions and calculations of
Eck\=1\(82),Eck\=1\(95),E
ck\=2\(82),and
Eck\=2\(95).
[[Page 6815]]
Table 16.--Distribution of Fractional Hours Within Cooling Season
Temperature Bins
------------------------------------------------------------------------
Fraction of
Bin Representative total
Bin number, j temperature temperature temperature
range for bin deg.F bin hours,
deg.F nj/N
------------------------------------------------------------------------
1............................. 65-69 67 0.214
2............................. 70-74 72 0.231
3............................. 75-79 77 0.216
4............................. 80-84 82 0.161
5............................. 85-89 87 0.104
6............................. 90-94 92 0.052
7............................. 95-99 97 0.018
8............................. 100-104 102 0.004
------------------------------------------------------------------------
4.1.2.2 Units covered by Section 3.2.2.2 where indoor fan capacity
modulation is used to adjust the sensible to total cooling capacity
ratio. Calculate SEER as specified in Section 4.1.1.
4.1.3 SEER calculations for an air conditioner or heat pump having
a two-capacity compressor. Calculate SEER using Equation 4.1-1.
Evaluate the space cooling capacity,
Qck\=1\(Tj), and electrical power
consumption, Eck\=1\(Tj), of the test
unit when operating at low compressor capacity and outdoor temperature
Tj using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.060
[GRAPHIC] [TIFF OMITTED] TP22JA01.061
where Qck\=1\(95) and
Eck\=1\(95) are determined from the A 1
Test, Qck\=1\ (82) and
Eck\=1\ (82) are determined from the B1
Test, and all are calculated as specified in Section 3.3. For two-
capacity units that lock out low capacity operation at outdoor
temperatures less than 95 deg.F (but greater than 82 deg.F), use
Equations 4.1.4-1 and 4.1.4-2 rather than Equations 4.1.3-1 and 4.1.3.2
for estimating performance at low compressor capacity. Evaluate the
space cooling capacity, Qck\=2\(Tj),
and electrical power consumption,
Eck\=2\(Tj), of the test unit when
operating at high compressor capacity and outdoor temperature Tj
using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.062
[GRAPHIC] [TIFF OMITTED] TP22JA01.063
where Qck\=2\ (95) and
Eck\=2\(95) are determined from the A 2
Test, Qck\=2\ (82) and
Eck\=2\ (82) are determined from the B2
Test, and all are calculated as specified in Section 3.3.
The calculation of Equation 4.1-1 quantities
[GRAPHIC] [TIFF OMITTED] TP22JA01.174
differs depending on whether the test unit would operate at low
capacity (Section 4.1.3.1), cycle between low and high capacity
(Section 4.1.3.2), or operate at high capacity (Sections 4.1.3.3 and
4.1.3.4) in responding to the building load. For units that lock out
low capacity operation at higher outdoor temperatures, the manufacturer
must supply information regarding this temperature so that the
appropriate equations are used. Use Equation 4.1-2 to calculate the
building load, BL(T)j for each temperature bin.
4.1.3.1 Steady-state space cooling capacity at low compressor
capacity is greater than or equal to the building cooling load at
temperature Tj, Qck\=1\(Tj)
BL(Tj).
[GRAPHIC] [TIFF OMITTED] TP22JA01.064
where,
Xk=\1\(Tj) = the cooling mode low capacity load
factor for temperature bin j, dimensionless.
PLFj = 1 - CDc [ -
Xk=\1\(Tj)], the part load factor, dimensionless.
[GRAPHIC] [TIFF OMITTED] TP22JA01.065
fractional bin hours for the cooling season; the ratio of the number of
hours
[[Page 6816]]
during the cooling season when the outdoor temperature fell within the
range represented by bin temperature Tj to the total number
of hours in the cooling season, dimensionless.
[GRAPHIC] [TIFF OMITTED] TP22JA01.066
Obtain the fractional bin hours for the cooling season,
[GRAPHIC] [TIFF OMITTED] TP22JA01.066
from Table 16. Use Equations 4.1.3-1 and 4.1.3-2, respectively, to
evaluate Qck\=1\(Tj) and
Eck\=1\(Tj). If the optional tests
described in Section 3.2.3 and Table 5 are not conducted, set the
cooling mode cyclic degradation coefficient, CDc,
to the default value specified in Section 3.5.3. If these optional
tests are conducted, set CDc to the lower of:
a. The value calculated according to Section 3.5.3 or
b. The Section 3.5.3 default value of 0.25.
4.1.3.2 Unit alternates between high (k=2) and low (k=1)
compressor capacity to satisfy the building cooling load at temperature
Tj, Qck\=1\(Tj)
BL(Tj) Qck\=2\(Tj).
[GRAPHIC] [TIFF OMITTED] TP22JA01.067
where,
Xk=\1\(Tj)=
[GRAPHIC] [TIFF OMITTED] TP22JA01.068
the cooling mode, low capacity load factor for temperature bin j,
dimensionless.
- Xk=\2\(Tj)=1 -
Xk=\1\(Tj), the cooling mode, high capacity load
factor for temperature bin j, dimensionless.
Obtain the fractional bin hours for the cooling season,
[GRAPHIC] [TIFF OMITTED] TP22JA01.069
from Table 16. Use Equations 4.1.3-1 and 4.1.3-2, respectively, to
evaluate Qck\=1\(Tj) and
Eck\=1\(Tj). Use Equations 4.1.3-3 and
4.1.3-4, respectively, to evaluate
Qck\=2\(Tj) and
Eck\=2\(Tj).
4.1.3.3 Unit only operates at high (k=2) compressor capacity at
temperature Tj and its capacity is greater than the building
cooling load, BL (Tj)
Qck\=2\(Tj). This Section applies to
units that lock out low compressor capacity operation at higher outdoor
temperatures.
[GRAPHIC] [TIFF OMITTED] TP22JA01.070
[GRAPHIC] [TIFF OMITTED] TP22JA01.071
where,
Xk=\2\(Tj)= BL(Tj) /
Qck\=2\(Tj), the cooling mode high
capacity load factor for temperature bin j, dimensionless.
PLFj = 1 - CDc [1 -
Xk=\2\(Tj)], the part load factor, dimensionless.
Obtain the fractional bin hours for the cooling season,
[GRAPHIC] [TIFF OMITTED] TP22JA01.072
from Table 16. Use Equations 4.1.3-3 and 4.1.3-4, respectively, to
evaluate Qck=\2\(Tj) and
Eck=\2\(Tj). When evaluating the above
equation for part load factor at high capacity, use the same value of
CDc as used in the Section 4.1.3.1 calculations.
4.1.3.4 Unit must operate continuously at high (k=2) compressor
capacity at temperature Tj BL(Tj)
Qck=\2\(Tj).
[GRAPHIC] [TIFF OMITTED] TP22JA01.073
Obtain the fractional bin hours for the cooling season,
[GRAPHIC] [TIFF OMITTED] TP22JA01.074
from Table 16. Use Equations 4.1.3-3 and 4.1.3-4, respectively, to
evaluate Qck=\2\(Tj) and
Eck=\2\(Tj).
4.1.4 SEER calculations for an air conditioner or heat pump having
a variable-speed compressor. Calculate SEER using Equation 4.1-1.
Evaluate the space cooling capacity,
Qck=\1\(Tj), and electrical power
consumption, Eck=\1\(Tj), of the test
unit when operating at minimum compressor speed and outdoor temperature
Tj. use,
[GRAPHIC] [TIFF OMITTED] TP22JA01.075
where Qck=1(82) and
Eck=1(82) are determined from the B1
Test, Qck=1(67) and
Eck=1(67) are determined from the F1
Test, and all four quantities are calculated as specified in Section
3.3. Evaluate the space cooling capacity,
Qck=2(Tj), and electrical power
consumption, Eck=2(Tj), of the test
unit when operating at maximum compressor speed and outdoor temperature
Tj. Use Equations 4.1.3-3 and 4.1.3-4, respectively, where
Qck=2(95) and Eck=2(95) are
determined from the A2 Test, Qck=2(82)
and Eck=2(82) are determined from the B2
Test, and all four quantities are calculated as specified in Section
3.3. Calculate the space cooling capacity,
Qck=v(Tj), and electrical power
consumption, Eck=v(Tj), of the test
unit when operating at outdoor temperature Tj and the
intermediate compressor speed used during the Section 3.2.4 (and Table
6) EV Test using,
[[Page 6817]]
[GRAPHIC] [TIFF OMITTED] TP22JA01.076
where Qck=v(87) and
Eck=v(87) are determined from the EV
Test and calculated as specified in Section 3.3. Approximate the slopes
of the k=v intermediate speed cooling capacity and electrical power
input curves, MQ and ME, as follows:
[GRAPHIC] [TIFF OMITTED] TP22JA01.077
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.078
Calculating Equation 4.1-1 quantities
[GRAPHIC] [TIFF OMITTED] TP22JA01.079
differs depending upon whether the test unit would operate at minimum
speed (Section 4.1.4.1), operate at an intermediate speed (Section
4.1.4.2), or operate at maximum speed (Section 4.1.4.3) in responding
to the building load. Use Equation 4.1-2 to calculate the building
load, BL(Tj), for each temperature bin.
4.1.4.1 Steady-state space cooling capacity when operating at
minimum compressor speed is greater than or equal to the building
cooling load at temperature Tj,
Qck=1(Tj)
BL(Tj).
[GRAPHIC] [TIFF OMITTED] TP22JA01.080
where,
Xk=1(Tj) = BL(Tj) /
Qck=1(Tj), the cooling mode minimum
speed load factor for temperature bin j, dimensionless.
PLFj = 1 - CcD [1 -
Xk=1(Tj)], the part load factor, dimensionless.
[GRAPHIC] [TIFF OMITTED] TP22JA01.083
fractional bin hours for the cooling season; the ratio of the number of
hours during the cooling season when the outdoor temperature fell
within the range represented by bin temperature Tj to the
total number of hours in the cooling season, dimensionless.
Obtain the fractional bin hours for the cooling season,
[GRAPHIC] [TIFF OMITTED] TP22JA01.084
from Table 16. Use Equations 4.1.4-1 and 4.1.4-2, respectively, to
evaluate Qck=1(Tj) and
Eck=1(Tj). If the optional tests
described in Section 3.2.4 and Table 6 are not conducted, set the
cooling mode cyclic degradation coefficient, CDc,
to the default value specified in Section 3.5.3. If these optional
tests are conducted, set CDc to the lower of:
a. The value calculated according to Section 3.5.3 or
b. The Section 3.5.3 default value of 0.25.
4.1.4.2 Unit operates at an intermediate compressor speed (k=i) in
order to match the building cooling load at temperature Tj,
Qck=1(Tj) BL(Tj)
Qck=1(Tj).
[GRAPHIC] [TIFF OMITTED] TP22JA01.085
where,
Qck=i(Tj) = BL(Tj), the
space cooling capacity delivered by the unit in matching the building
load at temperature Tj, Btu/h. The matching occurs with the
unit operating at compressor speed k = i.
Eck=i(Tj) =
[GRAPHIC] [TIFF OMITTED] TP22JA01.086
the electrical power input required by the test unit when operating at
a compressor speed of k = i and temperature Tj, W.
EERk=i(Tj) = the steady-state energy efficiency
ratio of the test unit when operating at a compressor speed of k = i
and temperature Tj, Btu/h per W.
Obtain the fractional bin hours for the cooling season,
[GRAPHIC] [TIFF OMITTED] TP22JA01.087
from Table 16. For each temperature bin where the unit operates at an
intermediate compressor speed, determine the energy efficiency ratio
EERk=i(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.088
For each unit, determine the coefficients A, B, and C by conducting
the following calculations once:
[GRAPHIC] [TIFF OMITTED] TP22JA01.090
[GRAPHIC] [TIFF OMITTED] TP22JA01.095
[[Page 6818]]
where,
T1 = the outdoor temperature at which the unit, when
operating at minimum compressor speed, provides a space cooling
capacity that is equal to the building load
[Qck=i(T1) =
BL(T1)], deg.F. Determine T1 by equating
Equations 4.1.4-1 and 4.1-2 and solving for outdoor temperature.
Tv = the outdoor temperature at which the unit, when
operating at the intermediate compressor speed used during the Section
3.2.4 EV Test, provides a space cooling capacity that is
equal to the building load [Qck=v(Tv)
= BL(Tv)], deg.F. Determine Tv by equating
Equations 4.1.4-3 and 4.1-2 and solving for outdoor temperature.
T2 = the outdoor temperature at which the unit, when
operating at maximum compressor speed, provides a space cooling
capacity that is equal to the building load
[Qck=2(T2) =
BL(Tv)], deg.F. Determine T2 by equating
Equations 4.1.3-3 and 4.1-2 and solving for outdoor temperature.
[GRAPHIC] [TIFF OMITTED] TP22JA01.089
4.1.4.3 Unit must operate continuously at maximum (k=2) compressor
speed at temperature Tj, BL(Tj)
Qck=2(Tj). Evaluate the
Equation 4.1-1 quantities
[GRAPHIC] [TIFF OMITTED] TP22JA01.091
as specified in Section 4.1.3.4 with the understanding that
Qck=2(Tj) and
Eck=2(Tj) correspond to
maximum compressor speed operation and are derived from the results of
the tests specified in Section 3.2.4.
4.2 Heating Seasonal Performance Factor (HSPF) Calculations. Six
generalized climatic regions are depicted in Figure 2 and otherwise
defined in Table 17. For each of these regions and for each applicable
standardized design heating requirement, evaluate the heating seasonal
performance factor using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.092
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.093
the ratio of the electrical energy consumed by the heat pump during
periods of the space heating season when the outdoor temperature fell
within the range represented by bin temperature Tj to the
total number of hours in the heating season (N), W.
[GRAPHIC] [TIFF OMITTED] TP22JA01.094
the ratio of the electrical energy used for resistive space heating
during periods when the outdoor temperature fell within the range
represented by bin temperature Tj to the total number of
hours in the heating season (N), W. Except as noted in Section 4.2.1.2,
resistive space heating is modeled as being used to meet that portion
of the building load that the heat pump does not meet because of
insufficient capacity or because the heat pump automatically turns off
at the lowest outdoor temperatures.
Tj = the outdoor bin temperature, deg.F. Outdoor
temperatures are ``binned'' such that calculations are only performed
based one temperature within the bin. Bins of 5 deg.F are used.
[GRAPHIC] [TIFF OMITTED] TP22JA01.081
fractional bin hours for the heating season; the ratio of the number of
hours during the heating season when the outdoor temperature fell
within the range represented by bin temperature Tj to the
total number of hours in the heating season, dimensionless. Obtain
[GRAPHIC] [TIFF OMITTED] TP22JA01.096
values from Table 17.
j = the bin number, dimensionless.
J = for each generalized climatic region, the total number of
temperature bins, dimensionless. Referring to Table 17, J is the
highest bin number (j) having a nonzero entry for the fractional bin
hours for the generalized climatic region of interest.
Fdef = the demand defrost credit described in Section 3.9.2,
dimensionless.
BL(Tj) = the building space conditioning load corresponding
to an outdoor temperature of Tj for a given generalized climatic region
and design heating requirement, Btu/h.
[[Page 6819]]
Table 17.--Generalized Climatic Region Information
----------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------
Region Number................................. I II III IV V VI
----------------------------------------------------------------------------------------------------------------
Heating Load Hours, HLH....................... 750 1250 1750 2250 2750 *2750
Outdoor Design Temperature, Tod............... 37 27 17 5 -10 30
----------------------------------------------------------------------------------------------------------------
j Tj( deg.F) Fractional Bin Hours, nj/N
----------------------------------------------------------------------------------------------------------------
1.................................. 62 .291 .215 .153 .132 .106 .113
2.................................. 57 .239 .189 .142 .111 .092 .206
3.................................. 52 .194 .163 .138 .103 .086 .215
4.................................. 47 .129 .143 .137 .093 .076 .204
5.................................. 42 .081 .112 .135 .100 .078 .141
6.................................. 37 .041 .088 .118 .109 .087 .076
7.................................. 32 .019 .056 .092 .126 .102 .034
8.................................. 27 .005 .024 .047 .087 .094 .008
9.................................. 22 .001 .008 .021 .055 .074 .003
10................................. 17 0 .002 .009 .036 .055 0
11................................. 12 0 0 .005 .026 .047 0
12................................. 7 0 0 .002 .013 .038 0
13................................. 2 0 0 .001 .006 .029 0
14................................. -3 0 0 0 .002 .018 0
15................................. -8 0 0 0 .001 .010 0
16................................. -130 0 0 0 .005 0 0
17................................. -18 0 0 0 0 .002 0
18................................. -23 0 0 0 0 .001 0
----------------------------------------------------------------------------------------------------------------
*Pacific Coast Region.
Evaluate the building heating load using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.097
where,
TOD = the outdoor design temperature, deg.F. An outdoor
design temperature is specified for each generalized climatic region in
Table 17.
C = 0.77, a correction factor which tends to improve the agreement
between calculated and measured building loads, dimensionless.
DHR = the design heating requirement (see Definition 1.21), Btu/h.
Calculate the minimum and maximum design heating requirements for each
generalized climatic region as follows:
[GRAPHIC] [TIFF OMITTED] TP22JA01.098
and
[GRAPHIC] [TIFF OMITTED] TP22JA01.099
where Qhk(47) is expressed in units of Btu/h and
otherwise defined as follows:
1. For a single-speed heat pump tested as per Section 3.6.1,
Qhk(47) = Qhk(47), the
space heating capacity determined from the H1 Test.
2. For a variable-speed heat pump, a Section 3.6.2 single-speed
heat pump, or a two-capacity heat pump not covered by item 3,
Qhk(47) = Qhk=2(47), the
space heating capacity determined from the H1N Test.
3. For two-capacity heat pumps that are designed to operate
exclusively, via an equipment lockout feature, at low compressor
capacity when space cooling while using both high and low capacities
when space heating, Qhk(47) =
Qhk(47), the space heating capacity determined
from the H1n Test.
If the optional H1N Test is conducted on a variable-speed
heat pump, the manufacturer has the option of defining
Qhk(47) as specified above in item 2 or as
Qhk(47) = Qhk=N(47), the
space heating capacity determined from the H1N Test.
Table 18.--Standardized Design Heating Requirements (Btu/h)
------------------------------------------------------------------------
------------------------------------------------------------------------
5,000 25,000 50,000 90,000
10,000 30,000 60,000 100,000
15,000 35,000 70,000 110,000
20,000 40,000 80,000 130,000
------------------------------------------------------------------------
[[Page 6820]]
4.2.1 Additional steps for calculating the HSPF of a heat pump
having a single-speed compressor that was tested with a fixed-speed
indoor fan installed, a constant-air-volume-rate indoor fan installed,
or with no indoor fan installed.
[GRAPHIC] [TIFF OMITTED] TP22JA01.100
[GRAPHIC] [TIFF OMITTED] TP22JA01.101
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.102
whichever is less; the heating mode load factor for temperature
binj, dimensionless.
Qh(Tj) = the space hearing capacity of the heat
pump when operating at outdoor temperature Tj, Btu/h.
Eh(Tj) = the electrical power consumption of the
heat pump when operating at outdoor temperature Tj, W.
(Tj) = the heat pump low temperature cut-out
factor, dimensionless.
PFLj = 1 - CD>h [1 -
X(Tj)], the part load factor, dimensionless.
Use Equation 4.2-2 to determine BL(Tj). Obtain fractional
bin hours for the heating season, nj/N, from Table 17. If
the optional H1C Test described in Section 3.6.1 is not conducted, set
the heating mode cyclic degradation coefficient,
CDh, to the default value specified in Section
3.8.1. If this optional test is conducted, set CDh
to the lower of:
a. The value calculated according to Section 3.8.1 or
b. The Section 3.8.1 default value of 0.25.
Determine the low temperature cut-out factor using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.103
where,
Toff = the outdoor temperature when the compressor is
automatically shut off, deg.F. (If no such temperature exists, Tj
is always greater than Toff and Ton).
Ton = the outdoor temperature when the compressor is
automatically turned back on, if applicable, following an automatic
shut-off, deg.F.
For non-defrost heat pumps covered under Section 3.6.1.1, determine its
space heating capacity, Qh(Tj), and the
electrical power consumption, Eh(Tj), as
specified in Section 4.2.1.1. For heat pumps having a heat comfort
controller that are covered under Section 3.6.1.2, determine
Qh(Tj) and Eh(Tj) as
specified in Section 4.2.1.2. For all other heat pumps covered under
Section 4.2.1 (and Section 3.6.1), calculate
Qh(Tj) and Eh(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.104
[GRAPHIC] [TIFF OMITTED] TP22JA01.105
[[Page 6821]]
where
Qh(47) and Eh(47) are determined from the H1 Test
and calculated and as specified in Section 3.7; Qh(35) and
Eh(35) are determined from the H2 Test and calculated as
specified in Section 3.9.1; and Qh(17) and Eh(17)
are determined from the H3 Test and calculated as specified in Section
3.10.
4.2.1.1 Space heating capacity and the electrical power
consumption calculations for a non-defrost heat pump. Calculate the
space heating capacity, Qh(Tj), and the
electrical power consumption, Eh(Tj), for a non-
defrost heat pump covered under Section 3.6.1.1 using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.106
where
Q h(62) and Eh(62) are determined from the H0
Test, Qh(47) and Eh(47) are determined from the
H1 Test, and all four quantities are calculated as specified in Section
3.7. The low temperature cut-out factor, (Tj), must be
greater than or equal to 37 deg.F, in accordance with Section 3.6.1.1.
4.2.1.2 Space heating capacity and the electrical power
consumption calculations for a heat pump having a heat comfort
controller. Calculate the space heating capacity and electrical power
of the heat pump without the heat comfort controller being active as
specified in Section 4.2.1 (Equations 4.2.1-4 and 4.2.1-5) for each
outdoor bin temperature, Tj, that is listed in Table 17.
Denote these capacities and electrical powers by using the subscript
``hp'' instead of ``h.'' Calculate the mass flow rate (expressed in
pounds-mass of dry air per hour) and the specific heat of the indoor
air (expressed in Btu/lbmda deg.F) from the
results of the H1 Test using:
[GRAPHIC] [TIFF OMITTED] TP22JA01.107
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.108
are defined following Equation 3-1. For each outdoor bin temperature
listed in Table 17, calculate the nominal temperature of the air
leaving the heat pump condenser coil using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.109
For outdoor bin temperatures where To(Tj) is
equal to or greater than TCC,, the maximum supply
temperature determined according to Section 3.1.9, determine Q
h(Tj) and Eh(Tj) as
specified in Section 4.2.1 [i.e., Qh(Tj) =
Qhp(Tj) and Eh(Tj) =
Ehp(Tj)].
For outdoor bin temperatures where To(Tj)
TCC, Qh(Tj) = Qhp(Tj) +
QCC(Tj)
[GRAPHIC] [TIFF OMITTED] TP22JA01.110
Calculate the HSPF of a heat pump having a heat comfort controller
as specified in Section 4.2.1 with the exception of using the space
heating capacity and electrical power given above
[Qh(Tj) and Eh(Tj)] for the
calculations at each outdoor bin temperature.
4.2.2 Additional steps for calculating the HSPF of a heat pump
having a single-speed compressor and a variable-speed, variable-air-
volume-rate indoor fan. The manufacturer must provide information about
how the indoor air volume rate or the indoor fan speed varies over the
outdoor temperature range of 65 deg.F to -23 deg.F. Calculate the
quantities
[GRAPHIC] [TIFF OMITTED] TP22JA01.111
in Equation 4.2-1 as specified in Section 4.2.1 with the exception of
replacing references to the H1C Test and Section 3.6.1 with the
H1C1 Test and Section 3.6.2. In addition, evaluate the space
heating capacity and electrical power consumption of the heat pump
[Qh(Tj) and Eh(Tj)] using,
[[Page 6822]]
[GRAPHIC] [TIFF OMITTED] TP22JA01.113
where the space heating capacity and electrical power consumption at
both low capacity (k=1) and high capacity (k=2) at outdoor temperature
Tj are determined using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.114
For units where indoor fan speed is the primary control variable,
FPhk=1 denotes the fan speed used
during the required H11 and H31 Tests (see Table
10), FPhk=2 denotes the fan speed used
during the required H12, H22, and H32
Tests, and FPh(Tj) denotes the fan speed used by
the unit when the outdoor temperature equals Tj. For units
where indoor air volume rate is the primary control variable, the three
FPh's are similarly defined only now being expressed in
terms of air volume rates rather than fan speeds. Determine
Qhk=1 (47) and
Ehk=1 (47) from the H11
Test, and Qhk=2 (47) and
Ehk=2 (47) from the H12
Test. Calculate all four quantities as specified in Section 3.7.
Determine Qhk=1 (35) and Ehk=1
(35) as specified in Section 3.6.2; determine Qhk=2
(35) and Ehk=2 (35) from the H22 Test
and the calculation specified in Section 3.9. Determine
Qhk=1 (17) and Ehk=1 (17)
from the H31 Test, and Qhk=2 (17) and
Ehk=2 (17) from the H32 Test.
Calculate all four quantities as specified in Section 3.10.
4.2.3 Additional steps for calculating the HSPF of a heat pump
having a two-capacity compressor. The calculation of the Equation 4.2-1
quantities
[GRAPHIC] [TIFF OMITTED] TP22JA01.115
and
[GRAPHIC] [TIFF OMITTED] TP22JA01.116
differs depending upon whether the heat pump would operate at low
capacity (Section 4.2.3.1), cycle between low and high capacity
(Section 4.2.3.2), or operate at high capacity (Sections 4.2.3.3 and
4.2.3.4) in responding to the building load. For heat pumps that lock
out high and/or low capacity operation at low outdoor temperatures, the
manufacturer must supply information regarding the cutoff
temperature(s) so that you can select the appropriate equations.
a. Evaluate the space heating capacity and electrical power
consumption of the heat pump when operating at low compressor capacity
and outdoor temperature Tj using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.117
[[Page 6823]]
b. Evaluate the space heating capacity and electrical power
consumption [Qhk=2(Tj) and
Ehk=2(Tj)] of the heat pump when
operating at high compressor capacity and outdoor temperature Tj
by solving Equations 4.2.2-1 and 4.2.2-2, respectively, for k=2.
Determine Qhk=1 (62) and Ehk=1
(62) from the H01 Test, Qhk=1 (47) and
Ehk=1 (47) from the H11 Test, and
Qhk=2 (47) and Ehk=2 (47)
from the H12 Test. Calculate all six quantities as specified
in Section 3.7. Determine Qhk=2 (35) and
Qhk=2 (35) from the H22 Test and, if
required as described in Section 3.6.3, determine Qhk=1
(35) and Ehk=1 (35) from the H21 Test.
Calculate the required 35 deg.F quantities as specified in Section
3.9. Determine Qhk=2 (17) and
Ehk=2 (17) and from the H32 Test and,
if required as described in Section 3.6.3, determine
Qhk=1 (17) and Ehk=1 (17)
from the H31 Test. Calculate the required 17 deg.F
quantities as specified in Section 3.10.
4.2.3.1 Steady-state space heating capacity when operating at low
compressor capacity is greater than or equal to the building heating
load at temperature Tj, Qh
k=1(Tj) BL(Tj).
[GRAPHIC] [TIFF OMITTED] TP22JA01.118
where,
Xk=1= BL(Tj/
Qhk=1(Tj), the heating mode low
capacity load factor for temperature bin j, dimensionless.
PLFj= 1 - CDh [1 -
Xk=1(Tj)], the part load factor, dimensionless.
'(Tj = the low temperature cutoff factor,
dimensionless.
If the optional H0C1 Test described in Section 3.6.3 is
not conducted, set the heating mode cyclic degradation coefficient,
CDh, to the default value specified in Section
3.8.1. If this optional test is conducted, set CDh
to the lower of:
a. The value calculated according to Section 3.8.1 or
b. The Section 3.8.1 default value of 0.25.
Determine the low temperature cut-out factor using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.120
where toff and Ton are defined in Section 4.2.1.
Use the calculations given in Section 4.2.3.3, and not the above, if:
(1) the heat pump locks out low capacity operation at low outdoor
temperatures and
(2) Tj is below this lockout threshold temperature.
4.2.3.2 Heat pump alternates between high (k=2) and low (k=1)
compressor capacity to satisfy the building heating load at a
temperature Tj, Qhk=1(Tj)
BL(Tj) Qhk=2(Tj).
[GRAPHIC] [TIFF OMITTED] TP22JA01.121
[GRAPHIC] [TIFF OMITTED] TP22JA01.123
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.124
Xk=2(Tj) 1 - Xk=1(Tj),
the heating mode, high capacity load factor for temperature bin j,
dimensionless.
Determine the low temperature cut-out factor, (T), using
Equation 4.2.3-3.
4.2.3.3 Heat pump only operates at high (k=2) compressor capacity
at temperature Tj and its capacity is greater than the building heating
load, BL(Tj) Qhk=2(Tj).
This Section applies to units that lock out low compressor capacity
operation at low outdoor temperatures. Calculate
[GRAPHIC] [TIFF OMITTED] TP22JA01.125
using Equation 4.2.3-2. Evaluate
[GRAPHIC] [TIFF OMITTED] TP22JA01.126
using,
[[Page 6824]]
[GRAPHIC] [TIFF OMITTED] TP22JA01.127
where,
Xk=2(Tj)= BL(Tj) /
Qhk=2(Tj).
PLFj= 1 - CDh [1 -
Xk=2(Tj)].
When evaluating the above equation for part load factor at high
capacity, use the same value of CDh as used in
the Section 4.2.3.1 calculations. Determine the low temperature cut-out
factor, (Tj), using Equation 4.2.3-3.
4.2.3.4 Heat pump must operate continuously at high (k=2)
compressor capacity at temperature Tj, BL(Tj).
[GRAPHIC] [TIFF OMITTED] TP22JA01.128
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.129
4.2.4 Additional steps for calculating the HSPF of a heat pump
having a variable-speed compressor. Calculate HSPF using Equation 4.2-
1. Evaluate the space heating capacity,
Qhk=1(Tj), and electrical power
consumption, Ehk=1(Tj), of the heat
pump when operating at minimum compressor speed and outdoor temperature
Tj using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.130
where Qhk=1(62) and
Ehk=1(62) are determined from the H01
Test, Qhk=1(47) and
Ehk=1(47) are determined from the H11
Test, and all four quantities are calculated as specified in Section
3.7. Evaluate the space heating capacity,
Qhk=2(Tj), and electrical power
consumption, Ehk=2(Tj), of the heat
pump when operating at maximum compressor speed and outdoor temperature
Tj by solving Equations 4.2.2-1 and 4.2.2-2, respectively,
for k=2. Determine the Equation 4.2.2-1 quantities
Qhk=2(47) and Ehk=2(47)
from the H12 Test and the calculations specified in Section
3.7. Determine Qhk=2(35) and
Ehk=2(35) from the H22 Test and the
calculations specified in Section 3.9 or, if the H22 Test is
not conducted, by conducting the calculations specified in Section
3.6.4. Determine Qhk=2(17) and
Ehk=2(17) from the H32 Test and the
calculations specified in Section 3.10. Calculate the space heating
capacity, Qhk=i(Tj), and electrical
power consumption, Ehk=1(Tj), of the
heat pump when operating at outdoor temperature Tj and the
intermediate compressor speed used during the Section 3.6.4 H2V
Test using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.131
where Qhk=v(35) and
Ehk=v(35) are determined from the H2V
Test and calculated as specified in Section 3.9. Approximate the slopes
of the k=v intermediate speed heating capacity and electrical power
input curves, MQ and ME, as follows:
[[Page 6825]]
[GRAPHIC] [TIFF OMITTED] TP22JA01.132
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.133
Use Equations 4.2.4-1 and 4.2.4-2, respectively, to calculate
Qhk=1(35) and Ehk=1(35).
The calculation of Equation 4.2-1 quantities
[GRAPHIC] [TIFF OMITTED] TP22JA01.134
differs depending upon whether the heat pump would operate at minimum
speed (Section 4.2.4.1), operate at an intermediate speed (Section
4.2.4.2), or operate at maximum speed (Section 4.2.4.3) in responding
to the building load.
4.2.4.1 Steady-state space heating capacity when operating at
minimum compressor speed is greater than or equal to the building
heating load at temperature Tj,
Qhk=1(Tj)
BL(Tj). Evaluate the Equation 4.2-1 quantities
[GRAPHIC] [TIFF OMITTED] TP22JA01.135
as specified in Section 4.2.3.1. Except now use Equations 4.2.4-1 and
4.2.4-2 to evaluate Qhk=1(Tj) and
Ehk=1(Tj), respectively, and replace
Section 4.2.3.1 references to ``low capacity'' and Section 3.6.3 with
``minimum speed'' and Section 3.6.4. Also, the last sentence of Section
4.2.3.1 does not apply.
4.2.4.2 Heat pump operates at an intermediate compressor speed
(k=i) in order to match the building heating load at a temperature
Tj, Qhk=1(Tj)
BL(Tj) Qhk=2(Tj).
Calculate
[GRAPHIC] [TIFF OMITTED] TP22JA01.139
using Equation 4.2.3-2 while evaluating
[GRAPHIC] [TIFF OMITTED] TP22JA01.140
using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.141
where,
[GRAPHIC] [TIFF OMITTED] TP22JA01.142
and (Tj) is evaluated using Equation 4.2.3-3 while,
Qhk=i(Tj) = BL(Tj), the
space heating capacity delivered by the unit in matching the building
load at temperature Tj, Btu/h. The matching occurs with the
heat pump operating at compressor speed k=i.
COPhk=i(Tj) = the steady-state
coefficient of performance of the heat pump when operating at
compressor speed k=i and temperature Tj, dimensionless.
For each temperature bin where the heat pump operates at an
intermediate compressor speed, determine
COPhk=i(Tj) using,
[GRAPHIC] [TIFF OMITTED] TP22JA01.136
For each heat pump, determine the coefficients A, B, and C by
conducting the following calculations once:
[GRAPHIC] [TIFF OMITTED] TP22JA01.143
where,
T3 = the outdoor temperature at which the heat pump,
when operating at minimum compressor speed, provides a space heating
capacity that is equal to the building load
[Qh k=1(T3) = BL(T3)],
deg.F. Determine T3 by equating Equations 4.2.4-1 and 4.2-2
and solving for outdoor temperature.
Tvh = the outdoor temperature at which the heat pump,
when operating at the intermediate compressor speed used during the
Section 3.6.4 H2V Test, provides a space heating capacity
that is equal to the building load
[Qhk=v(Tvh) = BL(Tvh)],
deg.F. Determine Tvh by equating Equations 4.2.4-3 and 4.2-2
and solving for outdoor temperature.
T4 = the outdoor temperature at which the heat pump,
when operating at maximum compressor speed, provides a space heating
capacity that is equal to the building load
[Qhk=2(T4)] = BL(T4)],
deg.F. Determine T4 by equating Equations by 4.2.2-1 (k=2)
and 4.2-2 and solving for outdoor temperature.
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4.2.4.3 Heat pump must operate continuously at maximum (k=2)
compressor speed at temperature Tj, BL(Tj)
Qhk=2(Tj). Evaluate the
Equation 4.2-1 quantities
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as specified in Section 4.2.3.4 with the understanding that
Qhk=2(Tj) and Ehk=2
(Tj) correspond to maximum compressor speed operation and
are derived from the results of the specified Section 3.6.4 tests.
4.3 Calculations of the Actual and Representative Regional Annual
Performance Factors for Heat Pumps.
4.3.1 Calculation of actual regional annual performance factors
(APFA) for a particular location and for each standardized
design heating requirement.
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where,
CLHA = the actual cooling hours for a particular
location as determined using the map given in Figure 3, hr.
Qck(95)= the space cooling capacity of the
unit as determined from the A or A2 Test, whichever applies,
Btu/h.
HLHA = the actual heating hours for a particular
location as determined using the map given in Figure 2, hr.
DHR = the design heating requirement used in determining the HSPF;
refer to Section 4.2 and Definition 1.21, Btu/h.
C = defined in Section 4.2 following Equation 4.2-2, dimensionless.
SEER = the seasonal energy efficiency ratio calculated as specified
in Section 4.1, Btu/Wh.
HSPF = the heating seasonal performance factor calculated as
specified in Section 4.2 for the generalized climatic region that
includes the particular location of interest (see Figure 2), Btu/
Wh; the HSPF should preferably correspond to the actual
design heating requirement (DHR) if known. But it may correspond to one
of the standardized design heating requirements referenced in Section
4.2.
4.3.2 Calculation of representative regional annual performance
factors APFR) for each generalized climatic region and for
each standardized design heating requirement
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where,
CLHR = the representative cooling hours for each
generalized climatic region, Table 19, hr.
HLHR = the representative heating hours for each
generalized climatic region, Table 19, hr.
HSPF = the heating seasonal performance factor calculated as
specified in Section 4.2 for each generalized climatic region and for
each standardized design heating requirement within each region, Btu/
Wh.
The SEER, Qck(95), DHR, and C are the same
quantities as defined in Section 4.3.1. Figure 2 shows the generalized
climatic regions. Table 18 lists standardized design heating
requirements.
Table 19.--Representative Cooling and Heating Load Hours for Each
Generalized Climatic Region
------------------------------------------------------------------------
Region CLHR HLHR
------------------------------------------------------------------------
I....................................................... 2400 750
II...................................................... 1800 1250
III..................................................... 1200 1750
IV...................................................... 800 2250
V....................................................... 400 2750
VI...................................................... 200 2750
------------------------------------------------------------------------
4.4 Rounding of SEER, HSPF, and APF for reporting purposes. After
calculating SEER according to Section 4.1, round it off as specified in
subpart b, Sec. 430.23(m)(3)(i) of the Code of Federal Regulations.
Round Section 4.2 HSPF values and Section 4.3 APF values as per
paragraphs (ii) and (iii), respectively, of Subpart B,
Sec. 430.23(m)(3) of the Code of Federal Regulations.
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[FR Doc. 01-39 Filed 1-19-01; 8:45 am]
BILLING CODE 6450-01-P