[Federal Register Volume 88, Number 15 (Tuesday, January 24, 2023)]
[Proposed Rules]
[Pages 4091-4107]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-00942]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 88 , No. 15 / Tuesday, January 24, 2023 /
Proposed Rules
[[Page 4091]]
DEPARTMENT OF ENERGY
10 CFR Parts 429 and 430
[EERE-2022-BT-TP-0028]
Energy Conservation Program: Test Procedures for Central Air
Conditioners and Heat Pumps
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Request for information.
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SUMMARY: The U.S. Department of Energy (``DOE'') is undertaking the
preliminary stages of a rulemaking to consider amendments to the test
procedure for central air conditioners and heat pumps. Through this
request for information (``RFI''), DOE seeks data and information
regarding issues pertinent to whether amended test procedures would
more accurately or fully comply with the requirement that the test
procedure produces results that measure energy use during a
representative average use cycle or period of use for the product
without being unduly burdensome to conduct, or reduce testing burden.
DOE welcomes written comments from the public on any subject within the
scope of this document (including topics not raised in this RFI), as
well as the submission of data and other relevant information.
DATES: Written comments and information are requested and will be
accepted on or before February 23, 2023.
ADDRESSES: Interested persons are encouraged to submit comments using
the Federal eRulemaking Portal at www.regulations.gov, under docket
number EERE-2022-BT-TP-0028. Follow the instructions for submitting
comments. Alternatively, interested persons may submit comments,
identified by docket number EERE-2022-BT-TP-0028, by any of the
following methods:
Email: CACandHeatPump2022 [email protected]. Include the docket
number EERE-2022-BT-TP-0028 in the subject line of the message.
Postal Mail: Appliance and Equipment Standards Program, U.S.
Department of Energy, Building Technologies Office, Mailstop EE-5B,
1000 Independence Avenue SW, Washington, DC 20585-0121. Telephone:
(202) 287-1445. If possible, please submit all items on a compact disc
(``CD''), in which case it is not necessary to include printed copies.
Hand Delivery/Courier: Appliance and Equipment Standards Program,
U.S. Department of Energy, Building Technologies Office, 950 L'Enfant
Plaza SW, 6th Floor, Washington, DC 20024. Telephone: (202) 287-1445.
If possible, please submit all items on a CD, in which case it is not
necessary to include printed copies. No telefacsimiles (``faxes'') will
be accepted. For detailed instructions on submitting comments and
additional information on this process, see section III of this
document.
Docket: The docket for this activity, which includes Federal
Register notices, comments, and other supporting documents/materials,
is available for review at www.regulations.gov. All documents in the
docket are listed in the www.regulations.gov index. However, not all
documents listed in the index may be publicly available, such as
information that is exempt from public disclosure.
The docket web page can be found at www.regulations.gov/#!docketDetail;D=EERE-2022-BT-TP-0028. The docket web page contains
instructions on how to access all documents, including public comments,
in the docket. See section III for information on how to submit
comments through www.regulations.gov.
FOR FURTHER INFORMATION CONTACT:
Mr. Lucas Adin, U.S. Department of Energy, Office of Energy
Efficiency and Renewable Energy, Building Technologies Office, EE-2J,
1000 Independence Avenue SW, Washington, DC 20585-0121. Telephone:
(202) 287-5904. Email: [email protected]">ApplianceStandards[email protected].
Mr. Pete Cochran, U.S. Department of Energy, Office of the General
Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585-0121.
Telephone: (202) 586-9496. Email: [email protected].
For further information on how to submit a comment or review other
public comments and the docket, contact the Appliance and Equipment
Standards Program staff at (202) 287-1445 or by email:
[email protected]">ApplianceStandards[email protected].
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Introduction
A. Authority and Background
B. Rulemaking History
II. Request for Information
A. Scope and Definitions
B. Load-Based Testing
1. Background
2. Current DOE Test Procedures
3. Categorization of Test Concepts
4. Summaries of Selected Activities Investigating and Developing
New Test Methods for Central Air Conditioners and Heat Pumps
5. Request for Information
C. Stakeholder Requests for Test Improvements in Appendix M1
1. Shoulder-Season Fan Power Consumption
2. Power Consumption of Auxiliary Components
3. Low-Temperature Heating Performance
D. Additional Improvements in Appendix M1
1. Impact of Defrost on Performance
2. Inlet Duct Design for Accurate Measurement With Minimal
Length
3. Heat Comfort Controllers
4. Cut-Out and Cut-In Temperature Certification
5. Extending the Definition of Low-Static Blower-Coil Systems to
Single-Split Systems
6. Hybrid Heat Pumps
III. Submission of Comments
I. Introduction
Central air conditioners (``CACs'') and central air conditioning
heat pumps (``HPs'') (collectively, ``CAC/HPs'') are included in the
list of ``covered products'' for which DOE is authorized to establish
and amend energy conservation standards and test procedures. (42 U.S.C.
6292(a)(3)) DOE's energy conservation standards and test procedures for
CAC/HPs are prescribed at title 10 of the Code of Federal Regulations
(``CFR''), part 430 section 430.32(c), and 10 CFR part 430, subpart B,
appendix M1 (``appendix M1'') (titled ``Uniform Test Method for
Measuring the Energy Consumption of Central Air Conditioners and Heat
Pumps''). The following sections discuss DOE's authority to establish
and amend test
[[Page 4092]]
procedures for CAC/HPs as well as relevant background information
regarding DOE's consideration of test procedures for this product.
A. Authority and Background
The Energy Policy and Conservation Act, as amended (``EPCA''),\1\
authorizes DOE to regulate the energy efficiency of a number of
consumer products and certain industrial equipment. (42 U.S.C. 6291-
6317) Title III, Part B \2\ of EPCA established the Energy Conservation
Program for Consumer Products Other Than Automobiles, which sets forth
a variety of provisions designed to improve energy efficiency. These
products include CAC/HPs,\3\ the subject of this RFI. (42 U.S.C.
6292(a)(3))
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\1\ All references to EPCA in this document refer to the statute
as amended through the Energy Act of 2020, Public Law 116-260 (Dec.
27, 2020), which reflect the last statutory amendments that impact
Parts A and A-1 of EPCA.
\2\ For editorial reasons, upon codification in the U.S. Code,
Part B was redesignated Part A.
\3\ This rulemaking uses the term ``CAC/HP'' to refer
specifically to central air conditioners (which include heat pumps)
as defined by EPCA. (42 U.S.C. 6291(21))
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The energy conservation program under EPCA consists essentially of
four parts: (1) testing, (2) labeling, (3) Federal energy conservation
standards, and (4) certification and enforcement procedures. Relevant
provisions of EPCA specifically include definitions (42 U.S.C. 6291),
test procedures (42 U.S.C. 6293), labeling provisions (42 U.S.C. 6294),
energy conservation standards (42 U.S.C. 6295), and the authority to
require information and reports from manufacturers (42 U.S.C. 6296).
Federal energy efficiency requirements for covered products
established under EPCA generally supersede State laws and regulations
concerning energy conservation testing, labeling, and standards. (42
U.S.C. 6297) DOE may, however, grant waivers of Federal preemption for
particular State laws or regulations, in accordance with the procedures
and other provisions of EPCA. (42 U.S.C. 6297(d))
The Federal testing requirements consist of test procedures that
manufacturers of covered products must use as the basis for: (1)
certifying to DOE that their products comply with the applicable energy
conservation standards adopted pursuant to EPCA (42 U.S.C. 6295(s)),
and (2) making other representations about the efficiency of those
consumer products (42 U.S.C. 6293(c)). Similarly, DOE must use these
test procedures to determine whether the products comply with relevant
standards promulgated under EPCA. (42 U.S.C. 6295(s))
Under 42 U.S.C. 6293, EPCA sets forth the criteria and procedures
DOE must follow when prescribing or amending test procedures for
covered products. EPCA requires that any test procedures prescribed or
amended under this section be reasonably designed to produce test
results which measure energy efficiency, energy use or estimated annual
operating cost of a covered product during a representative average use
cycle or period of use and not be unduly burdensome to conduct. (42
U.S.C. 6293(b)(3))
EPCA also requires that, at least once every 7 years, DOE review
test procedures for all type of covered products, including CAC/HPs, to
determine whether amended test procedures would more accurately or
fully comply with the requirements that the test procedures are (1)
reasonably designed to produce test results which reflect energy
efficiency, energy use, and estimated operating costs during a
representative average use cycle or period of use and (2) not unduly
burdensome to conduct. (42 U.S.C. 6293(b)(1)(A)) If the Secretary
determines, on her own behalf or in response to a petition by any
interested person, that a test procedure should be prescribed or
amended, the Secretary shall promptly publish in the Federal Register
proposed test procedures and afford interested persons an opportunity
to present oral and written data, views, and arguments with respect to
such procedures. The comment period on a proposed rule to amend a test
procedure shall be at least 60 days and may not exceed 270 days. In
prescribing or amending a test procedure, the Secretary shall take into
account such information as the Secretary determines relevant to such
procedure, including technological developments relating to energy use
or energy efficiency of the type (or class) of covered products
involved. (42 U.S.C. 6293(b)(2)) If DOE determines that test procedure
revisions are not appropriate, DOE must publish its determination not
to amend the test procedures.
DOE is publishing this RFI to collect data and information to
inform its decision in satisfaction of the 7-year review requirement
specified in EPCA. (42 U.S.C. 6293(b)(1)(A))
B. Rulemaking History
DOE's energy conservation standards for CAC/HPs are currently
prescribed at 10 CFR 430.32(c), and test procedure at 10 CFR part 430,
subpart B, appendix M1.
On January 5, 2017, DOE published a final rule regarding the
Federal test procedures for CAC/HPs. 82 FR 1426 (``January 2017 CAC TP
final rule''). The January 2017 CAC TP final rule amended the current
test procedure at that time, 10 CFR part 430, subpart B, appendix M
(``appendix M'') and established appendix M1, use of which was required
beginning January 1, 2023, for any representations, including
compliance certifications, made with respect to the energy use or
efficiency of CAC/HPs. Appendix M provides for the measurement of the
cooling and heating performance of CAC/HPs using the seasonal energy
efficiency ratio (``SEER'') metric and heating seasonal performance
factor (``HSPF'') metric, respectively. Appendix M1 specifies a revised
SEER metric (i.e., ``SEER2'') and a revised HSPF metric (i.e.,
``HSPF2'').
On October 25, 2022, DOE published a final rule to address limited-
scope amendments to the existing test procedures for CAC/HPs in
appendix M and appendix M1. 87 FR 64550 (``October 2022 CAC TP final
rule''). The October 2022 CAC TP final rule provided changes to improve
the functionality of appendix M1 to address the issues identified in
test procedure waivers, improve representativeness, and correct
typographical issues raised by commenters. Id. In the October 2022 CAC
TP final rule, DOE noted that several commenters indicated the need for
further test procedure amendments beyond the scope of the rulemaking.
Id. at 87 FR 64554-64555. DOE received comments recommending
consideration of load-based testing methods, controls validation
(particularly for variable-speed systems), amended metrics, amended
definitions, and expansion of test methods to capture low-temperature
heating performance for heat pumps. Id. In its response to these
comments, DOE noted that it had initiated the rulemaking not as a
comprehensive revision that will satisfy the 7-year lookback
requirements (see 42 U.S.C. 6293(b)(1)(A)), but to address a limited
set of known issues, including those that have been raised through the
test procedure waiver process. 87 FR 64554. However, DOE also responded
that a future rulemaking may more comprehensively address the issues
raised by the commenters. Id.
DOE has considered the issues raised by stakeholders in two
separate categories: (1) consideration of load-based testing
methodologies that have been in development by multiple organizations
and whether certain aspects of these methodologies might be adopted
into the DOE test procedure (this is discussed in section II.B of this
RFI) and (2) issues with the current appendix M1 test procedure that
may or may not still be relevant when/if load-
[[Page 4093]]
based concepts are adopted in the DOE test procedure (these are
discussed in sections II.C and II.D of this RFI).
In summary, DOE is publishing this RFI to collect data and
information regarding the need for amendments to the test procedures
for CAC/HPs, including the issues raised by the commenters in the
previous rulemaking, and in satisfaction of the 7-year review
requirement specified in EPCA.
II. Request for Information
In the following sections, DOE has identified a variety of issues
on which it seeks input to determine whether, and if so how, an amended
test procedure for CAC/HPs would (1) more accurately or fully comply
with the requirements in EPCA that test procedures be reasonably
designed to produce test results which reflect energy use during a
representative average use cycle or period of use, without being unduly
burdensome to conduct (42 U.S.C. 6293(b)(3)); or (2) reduce testing
burden.
Additionally, DOE welcomes comments on any aspect of the existing
test procedures for CAC/HPs that may not specifically be identified in
this document.
A. Scope and Definitions
CAC/HPs are defined in 10 CFR 430.2. As laid out in section 1.1 of
appendix M1, the test procedure applies to CAC/HPs including the
following categories, all of which are defined either in 10 CFR 430.2
or in section 1.2 of appendix M1:
(a) Split-system air conditioners, including single-split, multi-
head mini-split, multi-split (including variable refrigerant flow
(``VRF'')), and multi-circuit systems;
(b) Split-system heat pumps, including single-split, multi-head
mini-split, multi-split (including VRF), and multi-circuit systems;
(c) Single-package air conditioners;
(d) Single-package heat pumps;
(e) Small-duct, high-velocity systems (including VRF);
(f) Space-constrained products--air conditioners; and
(g) Space-constrained products--heat pumps.
The definition for central air conditioner or central air
conditioning heat pump was last amended in the October 2022 CAC TP
final rule. DOE revised the central air conditioner or central air
conditioning heat pump definition so that it explicitly excluded
certain equipment categories that met the CAC/HP definition based on
their characteristics but are exclusively distributed in commerce for
commercial and industrial applications. 87 FR 64550, 64573. DOE noted
that there are certain types of equipment that meet the CAC/HP
definition but are exclusively distributed in commerce for commercial
and industrial applications, and that EPCA did not intend to regulate
as consumer products. Id.
Issue 1: DOE seeks information on whether the scope of CAC/HPs
covered by appendices M and M1 needs to be limited, expanded,
clarified, or revised in any way.
Issue 2: DOE seeks information on whether the definition of central
air conditioner or central air conditioning heat pump needs revision or
further clarifications.
B. Load-Based Testing
1. Background
As noted in section I.B of this RFI, several stakeholders in the
previous rulemaking encouraged DOE to review ways to improve the
representativeness of the test procedures for CAC/HPs. Specifically,
the Pacific Gas and Electric Company, San Diego Gas and Electric, and
Southern California Edison (collectively, the ``California Investor
Owned Utilities'' or ``CA IOUs''); the Appliance Standards Awareness
Project (``ASAP'') and American Council for an Energy-Efficient Economy
(``ACEEE'') (collectively, the ``Joint Advocates''); and the Northwest
Energy Efficiency Alliance (``NEEA'') all requested that DOE explore
approaches that would capture the performance of variable-speed and
multi-stage systems operating under native controls rather than under
fixed compressor and fan speed controls as required under the current
DOE test methods. (CA IOUs, No. 20 at pp. 2-3; Joint Advocates, No. 18
at p. 1; NEEA, No. 23 at p. 1) \4\
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\4\ The parenthetical reference provides a reference for
information located in the docket of DOE's rulemaking to develop
test procedures for central air conditioners and heat pumps (Docket
No. EERE-2021-BT-TP-0030, which is maintained at
www.regulations.gov). The references are arranged as follows:
(commenter name, comment docket ID number, page of that document).
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NEEA and the Joint Advocates recommended that DOE adopt a test
procedure that evaluates performance for variable-speed systems with
the heat pump operating using its native controls rather than using
fixed-speed overrides of controls. (NEEA, No. 23 at p. 1; Joint
Advocates, No. 18 at pp. 3-4) NEEA provided data to support their claim
that seasonal efficiency performance is highly dependent on the
installed firmware of the system. (Id. at pp. 3-4) NEEA compiled this
information in a report \5\ that was also cited by the Joint Advocates
in their comment. (Joint Advocates, No. 18 at p. 4)
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\5\ The report titled ``Heat Pump and Air Conditioner Efficiency
Ratings: Why Metrics Matter'' outlined how the built-in firmware of
variable-speed CAC/HPs can have a significant impact on real-world
performance, yet the firmware operation is explicitly excluded from
current rating procedures. The report presented the case that a much
better rating metric would utilize a load-based testing procedure
that fully characterizes heat pump performance under realistic
operating conditions, including the systems' built-in firmware.
Available at https://neea.org/resources/heat-pump-and-air-conditioner-efficiency-ratings-why-metrics-matter.
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NEEA also requested that DOE adopt a load-based test procedure with
the tested system operating under native controls. (NEEA, No. 23 at p.
2) NEEA again provided data concerning the representativeness of the
existing DOE test procedure as compared to field data. Id. NEEA cited
several ongoing projects related to the evaluation of load-based
testing of CAC/HP and recommended that DOE leverage this work as a part
of the next CAC/HP test procedure rulemaking. (Id. at pp. 5-7) NEEA
additionally requested that DOE consider increasing the amount of data
reported for heat pumps operating at part-load heating conditions,
specifically advocating for required reporting of coefficient of
performance (``COP'') for low-compressor-stage tests at 67 [deg]F and
47 [deg]F. (Id. at p. 7)
To address these comments, and in addition to the potential
improvements in appendix M1 outlined in sections II.C and II.D of this
RFI, DOE is exploring the potential of a load-based testing approach,
primarily for variable-speed CAC/HPs, to evaluate performance
characteristics that may not be captured by the existing steady-state
test methods outlined in appendix M1. DOE has also considered load-
based test methods that are also applicable for single- and two-stage
models. This section gives a brief introduction of the load-based
testing methodologies and summarizes the various efforts and test
programs that are investigating and developing new load-based test
methods.
2. Current DOE Test Procedures
As discussed, the current test procedures for CAC/HPs are given at
title 10 CFR part 430, subpart B, appendix M1. Beginning January 1,
2023, manufacturers must certify their systems under appendix M1 and
meet energy conservation standards in terms of EER2, SEER2, HSPF2, and
off-mode power.
a. Test Conditions
Appendix M1 uses a steady-state test concept where test room
conditions are kept within narrow operating tolerances for each test
point, and the CAC/HP
[[Page 4094]]
system is manually controlled to operate at the specified compressor
speed and airflow rate for each test point (i.e., the CAC/HP system's
controls are overridden to ensure constant operation at the speed and
airflow required by the DOE test procedure). While the DOE test
procedures do include transient tests to examine the impact of defrost
and compressor cycling, they do not incorporate any elements of load-
based testing \6\ in which the unit operates under its own native
controls in responding to conditioning loads. Several research projects
discussed in section II.B.4 have addressed development of load-based
test approaches.
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\6\ A load-based test method differs from the steady-state test
method currently used in DOE test procedures for air conditioning
and heat pump equipment. In a steady-state test method, the indoor
room is maintained at a constant temperature throughout the test. In
this type of test, any variable-speed or variable-position
components of air conditioners and heat pumps are set in a fixed
position, which is typically specified by the manufacturer. In
contrast, a load-based test has the conditioning load applied to the
indoor room using a load profile that approximates how the load
varies for units installed in the field. In this type of test, an
air conditioning system or heat pump is allowed to automatically
determine and vary its control settings in response to the imposed
conditioning loads, rather than relying on manufacturer-specified
settings.
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Furthermore, there has been growing interest in cold climate heat
pumps (``CCHPs''). A CCHP is a kind of central heat pump that could
provide mechanical air heating utilizing a refrigerant vapor
compression cycle, or a combination of mechanical air heating and
electric resistance heating, at low outdoor ambient conditions (~5
[deg]F) that could occur in generalized climate region V \7\ in the
United States. On May 19, 2021, DOE, in conjunction with the U.S.
Environmental Protection Agency (``EPA'') and National Resources Canada
(``NRCan''), announced a Cold Climate Heat Pump Technology Challenge
(``DOE CCHP Tech Challenge'') as part of the Energy, Emissions and
Equity (``E3'') Initiative.\8\ In partnership with heat pump
manufacturers, DOE developed a new technology specification for a high-
performance CCHP. Several CCHP prototypes meeting this technology
specification will undergo field trials in the winters of 2022 and 2023
to demonstrate performance in the field. In addition to the interest in
CCHP development expressed by heat pump manufacturers, DOE is aware of
growing interest from utilities and state governments to support the
development of CCHPs to accelerate decarbonization efforts (e.g.,
replacing residential furnaces with heat pumps). Utility programs often
offer rebates to consumers who purchase high-efficiency products, and
high-performing CCHP are a growing component of several utility rebate
programs.\9\
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\7\ See ``Figure 1--Climatic Regions I through VI for the United
States'' in appendix M1.
\8\ As part of the E3 Initiative, DOE launched the DOE CCHP Tech
Challenge. Currently, the challenge is focused on residential,
centrally ducted, electric-only HPs. CCHP products that meet the
challenge specification would offer high efficiency and heating
capacity both seasonally and at very cold temperatures (5 [deg]F and
below). The challenge builds upon the recent ENERGY STAR
specification (v6.1). For further details, see www.energy.gov/sites/default/files/2022-02/bto-cchp-fact-sheet-021822.pdf.
\9\ There currently is a database of CCHP products provided by
the Northeast Energy Efficiency Partners (``NEEP''), and some
utility providers are offering rebates if customers purchase and
install a CCHP from the NEEP database. For example, the Vermont
Public Power Supply Authority is offering one (vppsa.com/2021-cold-climate-heat-pump-instant-discount/).
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However, the validation of CCHP performance at colder outdoor
ambient temperatures (i.e., 5 [deg]F and colder), is not a topic
currently addressed by the DOE test procedures.
b. Control Inputs
When testing for single-speed and two-speed CAC/HPs, the heating
and cooling tests per the DOE test procedures are conducted using each
of the discrete compressor speeds at which the system is capable of
operating. However, when testing variable-speed CAC/HPs, appendix M1
requires selection of appropriate compressor speeds that are intended
to be representative of how the system would operate under its native
controls.\10\ The DOE test procedures include some specification as to
how compressor speeds should be selected for testing variable-speed
CAC/HP. For example, appendix M1 specifies that for the H32
heating test, the ``Heating Full'' compressor speed should be the
maximum speed at which the system controls would operate the compressor
in normal operation at 17 [deg]F ambient temperature. However, there is
no process for verifying that the compressor speeds selected for
testing agree with the compressor speed that would be observed if the
system were operating at the same conditions under native controls.
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\10\ Native controls means configuring the unit under test with
settings specified for field use and removing the unit from ``test
mode'' used for steady-state tests. Native control settings are
determined from manufacturer installation and operations manual
shipped with the unit.
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Additionally, single-speed and two-speed CAC/HP systems rely on
voltage signals from a thermostat to determine their operating state.
When following DOE's test procedures for single-speed and two-speed
CAC/HPs, it is common practice for the test lab to simulate a
thermostat signal by sending the appropriate voltage signals directly
to the unit under test instead of using a functional thermostat to
induce the desired stage of heating or cooling mode. Conversely,
variable-speed CAC/HPs installed in the field commonly utilize
communicating thermostats where the control system communicates the
difference in space temperature and space setpoint temperature to the
control that sets compressor speed and indoor fan speed. Manufacturers
involved in the development of the ENERGY STAR Central Air Conditioner
and Air Source Heat Pump Specification Version 6.0 indicated that
standard thermostats for their variable-speed units enable two-way
communication control between the indoor and outdoor units.\11\ DOE is
aware of concerns that two-way communication control may not be
possible using a third-party smart thermostat or lab-simulated
thermostat. Therefore, many variable-speed units would not operate
without their proprietary communicating thermostat making it an
inherent part of the native control. DOE is also aware of concerns that
operation under native controls for variable-speed CAC/HP can result in
dynamic operation that is inconsistent with the steady-state
requirements in the current DOE test procedure.
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\11\ Lennox and Carrier comments on the Version 6.0 Limited
Topic Proposal on Installation, dated February 23, 2021. Comments
are accessible at https://www.energystar.gov/products/spec/central_air_conditioner_and_air_source_heat_pump_specification_version_6_0_pd.
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3. Categorization of Test Concepts
As explained in section II.B.1 of this document, the current DOE
test procedure for CAC/HPs outlined in appendix M1 is a steady-state
test, where the compressor speeds and airflow rates may be overridden
for each test point.
In contrast, a load-based test has the conditioning load applied to
the indoor room using either a stable compensation load or a load
profile that approximates how the load varies for units installed in
the field. In this type of test, an air conditioning system or heat
pump is allowed to automatically determine and vary its operation in
response to the imposed conditioning loads, rather than operating at
manually overridden speeds.
Because of the different variations of load-based tests, it is
important to define the method of inducing the conditioning load on the
indoor psychrometric room. Broadly, there are two methods of inducing
load, which
[[Page 4095]]
are detailed in the following sections II.B.3.a and II.B.3.b of this
document.
a. Test Chamber Induced Load
In this approach, the test chamber's reconditioning equipment, and/
or any alternative devices such as a fan coil or electric heater, add
or remove heat to (or from) the chamber at a constant rate. An example
of the test chamber induced load is the load-compensation method, which
was first proposed by the German energy regulatory body, Bundesanstalt
f[uuml]r Materialforschung und-Pr[uuml]fung (``BAM'').\12\ Like all
load-based tests, the load-compensation method involves testing the
CAC/HP equipment operating without any test unit native controls
override (i.e., not in test mode). This approach minimizes the impact
on test result variation caused by test chamber and measurement
apparatus thermal mass due to the inherent steady-state nature of the
testing.
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\12\ BAM (2019). Proposal for the revision of the harmonised
test standard EN 14825:2016. Federal Institute for Materials
Research and Testing (BAM).
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This testing methodology can be illustrated by explanation of its
execution in the DOE CCHP Tech Challenge. Prior to conducting load-
compensation tests under native controls, appendix M1 tests are
required to calculate HSPF2 and determine target compensation loads for
a select sub-set of native control tests. During native control
testing, the psychrometric chambers are operated with a fixed cooling
load; this load should be equivalent in magnitude to the capacity from
the corresponding appendix M1 regulatory test. Full-load tests are
conducted with the thermostat set at the maximum available setpoint
unless temporary over speeding is allowed by the system controls. In
this case, the thermostat setpoint is reduced until temporary over
speeding is no longer occurring. Minimum and intermediate speed tests
are conducted with the thermostat set at the test condition target
value (adjusted for thermostat offset). For example, if a heating
capacity of 17,000 Btu/h was measured during the H11 test,
the ``Min/Mild'' test would apply an equivalent 17,000 Btu/h cooling
load to the indoor room's conditioning equipment. This results in the
unit under test responding to the test chamber-induced load to maintain
the desired temperature. If a similar capacity cannot be achieved
without the unit cycling on and off, then the compensation load is
incrementally increased until the unit is no longer cycling. Data is
collected with the unit operating at a capacity as close as possible to
the ratings test while running continuously (not cycling).
b. Virtual Building Load
The Virtual Building Load (``VBL'') approach of load-based testing
adds to the load-compensation approach by simulating the building
response to the conditioning provided by the unit under test.
Specifically, if the system capacity is lower than the average load in
a heating test, the temperature of the air returned to the unit would
be reduced (by the test chamber conditioning equipment) to reflect the
transient reduction in temperature of the building while the load and
unit capacity are not balanced. The main difference between the test
chamber induced load test method and the VBL test method is that the
former utilizes a stable load being imposed on the unit under test,
whereas the latter varies the load to simulate the building response if
the capacity of the unit under test does not match the imposed load.
Several variations exist for implementation of the VBL for load-based
testing of CAC/HPs, as detailed in section II.B.4 of this RFI. What all
these variations have in common is that the indoor room temperature
varies to mimic the response of the virtual building, which is a
software loop continuously interacting with the indoor room's
conditioning equipment.
4. Summaries of Selected Activities Investigating and Developing New
Test Methods for Central Air Conditioners and Heat Pumps
Several initiatives to investigate, research, and develop new test
procedures have emerged in response to concerns that current regulatory
test methods may have issues representing field performance. Some of
these activities are described in the subsections below.
a. CSA EXP07
In March 2019, The Canadian Standards Association (``CSA'')
published a draft ``first edition'' of CSA EXP07:19, ``Load-based and
climate-specific testing and rating procedures for heat pumps and air
conditioners'' \13\ (``EXP07''). EXP07 is a load-based testing
methodology applicable to single-split and packaged air-source CAC/HP
with rated cooling or heating capacity below 65,000 Btu/h, including
space-constrained and small-duct, high-velocity equipment. In contrast
to conventional test methods, in which the indoor room conditions are
held constant by the laboratory's indoor room conditioning equipment,
EXP07 allows the unit under test to respond to a thermostat or
temperature controller installed in the room or the return air, while
the indoor room conditioning equipment is controlled to adjust that
temperature to represent the conditioning (be it heating or cooling)
provided by the unit as well as the response of a typical building. The
test sequences through a set of representative outdoor room conditions.
As the unit attempts to maintain a desired condition, all modulating
components are free to perform under the unit's own native controls.
---------------------------------------------------------------------------
\13\ CSA EXP07:19 is available for purchase in the CSA Group
online store at www.csagroup.org/store/product/CSA%20EXP07%3A19. A
total of 86 different comments were received by stakeholders
regarding EXP07:19 during a technical review. A summary of the major
comments is detailed in this article: Bruce Harley, Mark Alatorre,
Christopher Dymond, Gary Hamer, ``CSA EXP07: Ongoing Progress,
Lessons Learned, and Future Work in Load-based Testing of
Residential Heat Pumps'' (2022). International Refrigeration and Air
Conditioning Conference. Paper 2477.
---------------------------------------------------------------------------
The load-based test concept that underpins the EXP07 procedure is
heavily dependent on the interaction of the unit under test, the test
chambers, and the thermostat. For CAC/HP systems equipped with a
communicating control system, typical for variable-speed systems, the
thermostat calculates the difference between the measured indoor room
temperature and the unit setpoint for the indoor room, and continuously
sends signals to the unit under test to control its operating state.
CSA EXP07 also requires that the make and model of the thermostat be
recorded and reported with test data.
b. AHRI 1230-2021 VRF CVP
On May 18, 2021, the Air-Conditioning, Heating, and Refrigeration
Institute (``AHRI'') published an updated test procedure (AHRI 1230-
2021) for Variable Refrigerant Flow Multi-Split Air Conditioners and
Heat Pumps that incorporates a controls verification procedure
(``CVP'') as appendix C \14\ (``VRF CVP''). AHRI 1230-2021 allows
manufacturers to specify control settings for certain ``critical
parameters'' (e.g., compressor speed, outdoor unit fan speed, and
outdoor unit valve positions) in supplemental testing instructions; the
VRF CVP is then used to verify whether these manufacturer-specified
critical parameter settings are within the range of settings that would
be used by the system during operation in the field. On October 20,
2022, DOE published a Final Rule regarding Federal test procedures for
VRFs. 87 FR 63860
[[Page 4096]]
(``October 2022 VRF TP final rule''). In the October 2022 VRF TP final
rule, DOE incorporated the CVP (via reference to Appendix C of AHRI
1230-2021) as part of DOE's product-specific enforcement provisions for
VRF multi-split systems in the proposed Sec. 429.134(s). Id.
---------------------------------------------------------------------------
\14\ See www.ahrinet.org/sites/default/files/2022-06/AHRI_Standard_1230-2021.pdf.
---------------------------------------------------------------------------
The VRF CVP is performed in the cooling mode by using the test room
conditioning apparatus to continuously reduce the indoor room
temperature throughout the duration of the procedure. The VRF system
responds as the temperature decreases and ``unloads'' as the demand
diminishes for the system to provide cooling capacity. Throughout the
CVP, the measured positions of each critical parameter are compared
against the certified critical parameter values. The certified critical
parameters are validated if a defined time exists from within the CVP
where the measured values are within tolerance of the certified values.
The VRF CVP is not used to measure capacity or efficiency; it is solely
used for validating whether critical parameter control inputs are
representative of behavior as observed under native control.
Additionally, the VRF CVP is not a fully load-based method.
The VRF CVP includes test provisions that are specific to the
operation of VRF systems, such as requirements governing the number of
thermally active indoor units and validation of critical parameters
that are all variable-speed or modulating-position. Additional
specification would be required to adapt the AHRI 1230-2021 CVP for VRF
systems into a similar CVP applicable for CAC/CHP equipment intended to
validate the operating states of variable-speed or modulating
components. It is important to note that the VRF CVP utilizes a dynamic
load that is neither constant nor simulates a virtual building load.
The magnitude of the load is dynamically decreased by explicitly
requiring the indoor temperature to be ramped down.
c. ENERGY STAR CCHP CVP
On January 27, 2022, EPA published the ENERGY STAR Version 6.1
Specification for CACs and Air-Source Heat Pumps (``ASHPs'').\15\ To
certify as an ENERGY STAR CCHP, systems must also meet criteria at the
5 [deg]F heating test condition and perform a controls verification
procedure to confirm that the system achieves the same capacity and
efficiency criteria at the 5 [deg]F test point when operating under
native controls. The ENERGY STAR CCHP CVP is used as pass/fail
verification criteria, rather than being used to develop a discrete
performance rating, and the system must meet verification criteria in
terms of capacity and efficiency.
---------------------------------------------------------------------------
\15\ See www.energystar.gov/sites/default/files/asset/document/ENERGY%20STAR%20Version%206.1%20Central%20Air%20Conditioner%20and%20Heat%20Pump%20Final%20Specification%20%28Rev.%20January%20%202022%29.pdf.
---------------------------------------------------------------------------
The ENERGY STAR CCHP CVP shares aspects of both load-based testing
and controls verification procedures. The method is similar to other
load-based test procedures in that the test unit operates under its
native controls. During the ENERGY STAR CCHP CVP, the system thermostat
is set to the highest achievable setpoint, while the indoor room
conditioning apparatus is set to control to the standardized 70 [deg]F
indoor room temperature used for heating tests.\16\ In cases in which
the required capacity is exceeded but the COP is lower than the
requirement, a modified test is allowed, in which the operating
capacity is reduced, to attempt to shift both capacity and COP into
compliance with the requirement. For this modified test, the thermostat
setting is reduced to the standardized room temperature, and the load
applied to the room is reduced. If the system can operate at a balance
point where both the COP and heating capacity requirements are met,
then the CCHP CVP is successful. This part of the ENERGY STAR CCHP CVP
is a load-based method, since the chamber conditioning system applies a
fixed load rather than maintaining chamber temperature.
---------------------------------------------------------------------------
\16\ This is referred to as a ``buried thermostat'' test. The
``buried'' term arose from use of the approach in cooling mode
testing, for which the term is consistent with using the lowest
setting.
---------------------------------------------------------------------------
d. BAM Dynamic Testing Method
On May 29, 2019, BAM proposed a load-based (compensation method)
test method (``Proposal for the revision of the harmonized test
standard EN 14825, for the testing and rating of air conditioners and
heat pumps at part load conditions and calculation of seasonal
performance''), to be used as an alternative to EN 14825:2016 ``Air
conditioners, liquid chilling packages and heat pumps, with
electrically driven compressors, for space heating and cooling. Testing
and rating at part load conditions and calculation of seasonal
performance'' (``EN 14825''). The proposal outlined several issues \17\
with the fixed compressor speed standard, EN 14825.
---------------------------------------------------------------------------
\17\ Section 2.3; May 29th BAM Proposal.
---------------------------------------------------------------------------
After consultations with stakeholders, BAM released test guidelines
based on their load-based test method on September 21st, 2020, for
ducted and non-ducted, single-split and packaged air-source CAC/HPs
with rated cooling or heating capacity below 41,000 Btu/h in a single
or double calorimeter room (``Test guideline for a load-based
performance testing and calculation of the seasonal performance (air
conditioners, cooling only)'').\18\
---------------------------------------------------------------------------
\18\ See: netzwerke.bam.de/Netzwerke/Content/DE/Downloads/Evpg/
Heizen-Kuehlen-Lueften/bam%20test%20guideline%20-%20load-
based%20testing%20of%20air%20conditioners%20cooling.pdf.pdf?__blob=pu
blicationFile.
---------------------------------------------------------------------------
Through round-robin testing of CAC/HP units using the fixed
compressor speed test procedure at seven different test labs, BAM found
the standard deviation of reproducibility for EN 14825 to be 7.8% with
a maximum deviation of 24% of Seasonal COP values. 19 20 BAM
did undergo some limited investigation of the repeatability and
reproducibility of the BAM Dynamic Testing method, and BAM claims that
their test method is both repeatable and reproducible.\21\ They found
the degree of repeatability using the BAM Dynamic Testing method to be
comparable (~2%) to the repeatability of the current fixed compressor
speed standard, EN 14825.\22\
---------------------------------------------------------------------------
\19\ Figure 4a, 29th May 2019 BAM Proposal. BAM cites that many
any labs were erroneously assuming various correction factors due to
ambiguities in EN 14825, and without the need for these correction
factors in a dynamic test procedure, BAM predicts that
reproducibility will be higher.
\20\ Table 2, 29th May 2019 BAM Proposal; BAM has not released
substantial test data on the reproducibility of their test procedure
in comparison to the European standard. Instead, they hypothesize
that without the ambiguities found in EN 14825 or correction
factors, the BAM Dynamic Test procedure will be more reproducible.
\21\ Figure 10 in the May 29, 2019, proposal features a
distribution of some of these results, but the document does not
provide substantiating data to back up their claim of repeatability
and reproducibility.
\22\ ``Results'' section, 29th May 2019 BAM Proposal.
---------------------------------------------------------------------------
BAM evaluated 15 CAC models during their preliminary testing for
the BAM Dynamic Testing method and found that the unfixed compressor
speed load compensation method results in, on average, an approximately
20% lower SEER compared to declared values.\23\ The reason for this
deviation was primarily due to varying behavior at part-load
conditions, typically when the outdoor ambient temperature was between
77 [deg]F and 86 [deg]F. Due to the different control strategies in
each of the
[[Page 4097]]
CACs, the pattern of cycling on and off varied unit to unit, and hence
affecting the SEER values. BAM observed that the compensation method
allowed for a better comparison between units with well-designed
control systems.
---------------------------------------------------------------------------
\23\ Figure 6, 29th May 2019 BAM Proposal. This figure displays
results from testing to the unfixed compressor, load compensation
method defined in section 8.5.2 of EN 14825. This method is not
exactly what the BAM Dynamic Testing method is, but the BAM Dynamic
Testing method is largely based off this.
---------------------------------------------------------------------------
e. 4E IEA
The Technology Collaboration Program on Energy Efficient End-use
Equipment, International Energy Agency (``4E TCP'') studied various
load-based testing techniques in order to see if it is possible to
develop a test method that improves testing representativeness of
variable-speed central air conditioners.\24\ 4E TCP conducted the
testing series (titled ``Project 2.0'') where three different variable-
speed CAC/CHP units were tested by utilizing aspects of published load-
based test procedures (BAM Dynamic Testing, CSA EXP07 and AHRI 1230
CVP).
---------------------------------------------------------------------------
\24\ ``Load-based Testing for Variable Speed Air Conditioners &
Heat Pumps Phase 1 Findings Webinar'' 4E IEA presentation (January
29, 2021). See https://www.iea-4e.org/wp-content/uploads/2021/08/AC-HP-Test-Methods-Phase-1-Key-Findings_Revised.pdf.
---------------------------------------------------------------------------
4E TCP presented their findings in a public webinar \25\ and
solicited feedback from stakeholders on the preferred test concept to
be used in a unified load-based test method. After investigative
testing, 4E IEA recommended either a compensation target load-based
method (if test condition/test operating tolerances, repeatability and
burden increases are acceptable to stakeholders), or a CVP would be
preferred if the tolerances and burden are not acceptable. They also
found that the dynamic load response test method is not repeatable in a
laboratory setting. Stakeholders indicated the projected 10%-15%
repeatability increase for a compensation target load-based test was
too large and that for regulatory purposes, the overridden steady-state
test would be preferred.
---------------------------------------------------------------------------
\25\ ``AC/HP Test Methods Investigative Testing: Phase 2
Preliminary Findings'' 4E IEA presentation (May 7, 2021). See
https://www.iea-4e.org/wp-content/uploads/2021/08/AC-HP-Test-Methods-Phase-2-key-Findings-2021-08-06-CLEAN.pdf.
---------------------------------------------------------------------------
On December 1, 2021, 4E IEA published a test method in ``Controls
Validation Method for Variable Speed Air Conditioners and Heat Pumps''
(``4E TCP AC/HP Controls Validation Method''). This test method
utilized the compensation target load-based method as a CVP for
confirmation against regulatory tests in which modulating component(s)
are overridden. This methodology is applicable to variable-speed ducted
and non-ducted single-split and packaged air-source CAC/CHP with rated
cooling or heating capacity below 65,000 Btu/h, including through-the-
wall air conditioners (``ACs'') and heat pumps (``HPs'').
f. DOE Cold-Climate Heat Pump Investigative Testing
To inform the development of test methods for Cold Climate Heat
Pump Test methods, DOE conducted investigative testing on 7 non-ducted
mini-split and 2 central-ducted split variable-speed heat pumps. All
heating regulatory tests as per appendix M/M1 were conducted, in
addition to the H42 test at 5 [deg]F (optional in appendix
M1), H52 test at -5 [deg]F, and H62 test at -15
[deg]F (not part of appendix M or M1). Load-based tests were conducted
using the load-compensation method for select appendix M1 conditions,
denoted by the ``x'' subscript, namely H1NX,
H11X, and H42X. The testing showed that
regulatory and load-based tests showed similar performance for ducted
units at 47 [deg]F heating maximum air volume rate condition
(H1N and H1NX). However, DOE found that
regulatory tests did not capture ``real-world'' performance at ambient
temperatures lower than 47 [deg]F. Specifically, DOE observed that the
compressor speeds and indoor fan speeds for load-based and regulatory
tests at ambient temperatures below 47 [deg]F differed by more than 11%
for some of the tested units. Additionally, DOE observed that units in
``test mode'' allowed operation below the point at which the native
control tests cut out.
g. DOE CCHP Tech Challenge
Performance of the CCHPs participating in the DOE CCHP Tech
Challenge (see II.B.2 for further details) is evaluated by testing at
the psychrometric chambers at Oak Ridge National Laboratory (``ORNL'').
The test matrix comprises the regulatory heating mode tests outlined in
appendix M1, with the H4/H42 test at outdoor ambient
temperature of 5 [deg]F being mandatory. Additionally, after
consultation with manufacturers, it was decided that a battery of CCHP-
Focused Dynamic Tests would be conducted based on the load-compensation
method.\26\ For variable-speed CCHPs to pass the DOE CCHP Tech
Challenge specifications, one of the requirements is that the minimum
capacity at 47 [deg]F, validated using the ``Min/Mild'' load-based
test, shall be at least 30% less than the nominal capacity at 47 [deg]F
(i.e., capacity for test H1N of appendix M1). So far, 10
manufacturers have committed to participate in the DOE CCHP Tech
Challenge, with three of them having successfully achieved the
challenge's standards to date.\27\
---------------------------------------------------------------------------
\26\ See www.energy.gov/sites/default/files/2021-10/bto-cchp-tech-challenge-spec-102521.pdf.
\27\ See www.energy.gov/articles/biden-harris-administration-announces-250-million-investment-inflation-reduction-act.
---------------------------------------------------------------------------
h. Emulator-Based Assessment Method for Dynamic Performance Evaluation
of Air Conditioners by Waseda University
Various groups at the Waseda University in Japan collaborated to
develop an emulator-based method for load-based testing of ACs.\28\ The
virtual room emulator simulates the return indoor air temperature based
on the input assumptions for a VBL. Consequently, the AC responds to
the simulated indoor air conditions by supplying cooling capacity
according to the response guided by its control system. Testing was
conducted, with and without the emulator enabled, on a 2-ton non-ducted
CHP, as per the conditions outlined in the Japanese Industrial
Standards annual performance tests (``JIS B 08615, 2013'') (i.e.,
indoor dry-bulb and wet-bulb temperatures of 80 [deg]F and 67 [deg]F,
respectively, and outdoor dry-bulb and wet-bulb temperatures of 95
[deg]F and 75 [deg]F, respectively, at a 25 percent loading condition).
It was found that the COP of the unit with the emulator enabled was 22
percent lower than the corresponding steady-state test (without the
emulator).
---------------------------------------------------------------------------
\28\ Niccolo Giannetti, Hifni Ariyadi, Yoichi Miyaoka, Jongsoo
Jeong, Kiyoshi Saito, ``Development of an Emulator-Based Assessment
Method for Representative Evaluation of the Dynamic Performance of
Air Conditioners '' (2022). International Refrigeration and Air
Conditioning Conference. Paper 2458. docs.lib.purdue.edu/iracc/2448/.
---------------------------------------------------------------------------
As a result of testing, the team at Waseda University was able to
identify several sources of errors and delays that affected the
modulation of indoor air temperature and humidity, such as the
emulator's calculation time delay, tracking of air flow rate,
temperature and humidity by the condition generator, heat transfer and
thermal capacity of the structure and instrumentation of the
psychrometric chamber, time delay of the various signals, and the
thermostat location.
i. The Advanced Heat Pump Coalition
The Advanced Heat Pump Coalition is a group of utilities and energy
efficiency advocates, namely NEEA, the Northeast Energy Efficiency
Partners (``NEEP''), the Midwest Energy Efficiency Alliance (``MEEA''),
NRCan, EPA, California Energy Commission, and the New York State Energy
Research and Development Authority (``NYSERDA''), that share knowledge
and resources to assist the market adoption of residential heat
[[Page 4098]]
pumps in the US.\29\ Workgroup 1 of this coalition aims to identify a
load-based test procedure for ASHPs that is more representative of
their performance in the field.
---------------------------------------------------------------------------
\29\ See www.mwalliance.org/advanced-heat-pump-coalition.
---------------------------------------------------------------------------
Initially, 13 heat pumps made by nine manufacturers were tested
using CSA EXP07:19 and AHRI 210/240 \30\ (``Performance Rating of
Unitary Air-conditioning & Air-source Heat Pump Equipment'') at the UL
Plano laboratory in Texas. Two were initially tested only in the
heating mode and 11 were tested in both heating and cooling modes to
generate a complete set of seasonal COP ratings. As previously
mentioned, EXP07 accounts for the on-board control algorithms of the
units under test. A comparison of the relationship between HSPF and
heating SCOP or SEER and cooling SCOP was not conducted due to the fact
that these are two different metrics based on different measurement
conditions and methodologies. However, comparing different models with
similar SEER and HSPF ratings to the results using the CSA EXP07 method
showed that the relative efficiencies of those models were
significantly different. The Coalition stated that the on-board
controls are a critical component of the heat pump's real performance
and should be accounted for in future test standards.
---------------------------------------------------------------------------
\30\ AHRI 210/240 establishes a method to rate residential
central air conditioners and heat pumps consistent with the test
procedure codified in 10 CFR part 430, subpart B, appendix M1.
---------------------------------------------------------------------------
j. ISO/TC 86/SC 6/TG 13
TG 13 (``Next generation of performance standards'') is a working
group of ISO/TC 86/SC 6 (``Testing and rating of air-conditioners and
heat pumps'') that is responsible for gathering information on various
activities pertaining to load-based testing methods for residential
CAC/HPs. Recently, lab testing results of several CAC/HPs using the BAM
Dynamic Testing Method (section II.B.4.d of this document), CSA-
EXP07:2019 (section II.B.4.a of this document), and the emulator-based
assessment method (section II.B.4.h of this document), along with
findings of the 4E IEA project (section II.B.4.e of this document),
have been presented to members of ISO/TC 86/SC6/TG 13. The subcommittee
has raised concerns about the repeatability and reproducibility of
load-based tests on several occasions (e.g., the ``Load-based test
method'' informal virtual meeting held on July 8th, 2022), and hence
encourage all ongoing and future research projects to address both of
these factors.
k. ASHRAE TC 8.11 Subcommittee Unitary Next Generation Test Procedure
The American Society of Heating, Refrigerating and Air-Conditioning
Engineers (``ASHRAE'') Technical Committee (``TC'') 8.11 \31\ is
concerned with the following AC and HP systems: (1) ducted unitary ACs/
HPs, (2) room ACs such as window mounted units and non-ducted split
systems, and (3) packaged terminal equipment. The TC 8.11 subcommittee
titled ``Unitary Next Generation Test Procedure Subcommittee'' was
developed with the aim of coordinating technical activities related to
the development of the next generation load-based test procedure for
unitary HVAC equipment. It is planning to develop a Research Topic
Acceptance Request (``RTAR''), which will enable identification of
ASHRAE Research Projects (``RPs'') to improve upon the reproducibility,
repeatability, and representativeness of load-based test procedures for
residential and commercial unitary AC/HP equipment.
---------------------------------------------------------------------------
\31\ ASHRAE's technical committees are responsible for
coordination of society-sponsored Research Projects (``RPs''),
reviewing technical papers, evaluating the need for standards, and
acting as the advisory board for the Society on all aspects of the
technology for which it is in charge.
---------------------------------------------------------------------------
5. Request for Information
As explained in section II.B.3, all load-based test methods are
characterized by how the load is applied on the test chamber. Two
primary testing procedures are used for capacity measuring, namely the
calorimetric or air enthalpy method. The calorimetric room method
measures the energy input to the equipment serving a known load added
into the conditioned room. Test chambers are typically limited to a
3.4-ton (12 kW) cooling capacity and are typically preferable for
testing non-ducted CAC/HPs. In contrast, the air enthalpy method is
typically employed in psychrometric chambers, and is geared towards
ducted equipment, but can accommodate non-ducted if needed. Table II-1
shows which of the two capacity measuring methods (i.e., calorimetric
room or air enthalpy) are used for each load-based test method, and
also show the load application scheme for each of them.
Table II-1--Applicability of Load-Based Test Methods to Equipment Types, and Procedure for Capacity Measurement
--------------------------------------------------------------------------------------------------------------------------------------------------------
Test procedure for capacity Type of equipment test method is Load application scheme
measurement applicable to ---------------------------------
Load-based test method --------------------------------------------------------------------
Calorimetric Air enthalpy Test chamber Virtual
room method Ducted Non-ducted induced load building load
--------------------------------------------------------------------------------------------------------------------------------------------------------
CSA EXP07......................................... ............... [check] [check] [check] ............... [check]
AHRI 1230-2021 VRF CVP............................ ............... [check] [check] [check] [check] ...............
Energy Star CCHP CVP.............................. ............... [check] [check] [check] [check] ...............
BAM Dynamic Testing Method........................ [check] ............... [check] [check] [check] ...............
DOE CCHP Investigative Testing.................... ............... [check] [check] ............... [check] ...............
DOE CCHP Tech Challenge........................... ............... [check] [check] ............... [check] ...............
Emulator-Based Assessment Method for Dynamic [check] ............... ............... [check] ............... [check]
Performance Evaluation of ACs....................
4E TCP AC/HP Controls Validation Method........... [check] [check] [check] [check] [check] ...............
--------------------------------------------------------------------------------------------------------------------------------------------------------
In the following sections, DOE has identified a variety of issues
on which it seeks input to determine whether, and if so, how, an
amended test procedure for CAC/HPs and CCHPs would more accurately or
fully comply with the requirements in EPCA that test procedures be
reasonably designed to produce test results that reflect energy use
during a representative average use cycle or period of use without
being unduly burdensome to conduct (42
[[Page 4099]]
U.S.C. 6293(b)(3)). DOE also seeks input on the most appropriate
application of such an amended test procedure.
a. Repeatability and Reproducibility
DOE is interested in information and data regarding the
repeatability and reproducibility of known load-based test methods.
Publicly available information on this topic for the load-based test
method initiatives discussed in section II.B.4 is very limited.
Presentations regarding the 4E IEA work on development of load-based
test procedures (see section II.B.4.e of this document) include claims
that the degree of repeatability and reproducibility of load-based test
procedures is extremely important, and through testing three different
units twice at different test labs, the COP was found to vary as much
as 10.6 percent during the load compensation method.\32\ In addition,
several units have been tested at two laboratories to assess the
repeatability and reproducibility of CSA EXP07 and AHRI 210/240, but
the information is only available to ISO/TC 86/SC 6/TG 13 and not to
the public. DOE is aware of ongoing efforts where it has been pointed
out during load-based testing that thermostat location within the
indoor environmental chambers is very crucial for repeatability of
load-based tests across different laboratories.\33\
---------------------------------------------------------------------------
\32\ Slide 24 of ``AC/HP Test Methods Investigative Testing:
Phase 2 Preliminary Findings'' 4E IEA presentation (May 7, 2021).
\33\ Cheng, Li; Patil, Akash; Dhillon, Parveen; Braun, James E.;
and Horton, W. Travis, ``Impact of Virtual Building Model and
Thermostat Installation on Performance and Dynamics of Variable-
Speed Equipment during Load-based Tests'' (2018). International
Refrigeration and Air Conditioning Conference. Paper 2078.
docs.lib.purdue.edu/iracc/2078.
---------------------------------------------------------------------------
Issue 3: DOE requests quantitative information regarding the
repeatability and reproducibility of load-based test procedures (not
limited to the developments discussed in section II.B.4 of this RFI).
Specifically, which of the approaches presented in section II.B.4 are
better in this regard, and what specific characteristics make them
better? How do the repeatability and reproducibility of load-based test
procedures compare to more conventional test methods that involve
operating the system with one or more fixed control setting? To what
extent do the differences in test facility characteristics lead to
different settings of control system parameters as a result of control
system learning (i.e., adaptation of control parameters in response to
``conditioned system'' behavior) and how much does this affect
different load-based test approaches? Please provide appropriate data
to the extent possible to support the information.
b. Field Performance
As described in sections II.B.1 and II.B.2 of this RFI,
stakeholders have expressed greater interest in load-based test
procedures based on the observation that variable-speed CAC/HPs may not
always operate in the field in a manner that is represented by
conventional testing using fixed speeds for the compressor and other
key components. Developers of load-based testing methods claim these
tests are more representative of an average use cycle than the fixed
compressor speed methods found in appendix M1. However, comprehensive
information comparing the results of different test methods with the
results of field operation have not been made public. Currently, DOE is
only aware of NEEP managing a field performance research study to
directly compare the representativeness of both EXP07 and appendix M1,
but the results of this research are expected in the 2nd quarter of
2023.\34\
---------------------------------------------------------------------------
\34\ See neep.org/request-proposals-heat-pump-rating-representativeness-project-0.
---------------------------------------------------------------------------
Issue 4: DOE seeks data showing how the representativeness of load-
based test procedures compares to that of more conventional fixed-speed
and fixed-setting test procedures. What are the key issues observed
that cause field performance of CAC/HPs to deviate from the predictions
of conventional testing, and has load-based testing provided more
representative predictions? Additionally, DOE is interested in any data
suggesting that CAC/HPs that were considered to be performing poorly in
the lab when tested using load-based methods also performed poorly when
installed in the field.
c. Test Burden
In addition to considering repeatability, reproducibility, and
representativeness when evaluating test procedures, DOE must also
consider the relative burdens associated with conducting test
procedures. One component of test burden is the total testing time,
which includes setup/commissioning/decommissioning, official test
points, and any time required to transition between test conditions.
Test burden also accounts for difficulties in repeatably achieving test
conditions (i.e., whether a test has a higher likelihood of needing to
be conducted multiple times to achieve a valid result). Another key
component of analyzing test burden is considering any upgrades to
laboratory equipment or capital expenditures required to conduct
testing. These upgrades may constitute considerable burden when large
capital expenditures are required.
Issue 5: DOE seeks information related to the test burden of load-
based test methods, including those discussed in this document and any
other method that may not be considered here. What is the test duration
and how does it compare with a regulatory test under the currently
prescribed DOE test method? How much time is needed for control system
learning (i.e., adaptation of control parameters in response to
``conditioned system'' behavior) to take place prior to testing? What
specific changes to the facility, including its control systems, are
required to conduct load-based testing? Additionally, what are the
costs associated with upgrading controls of environmental chambers and
the time needed for training technicians to successfully conduct load-
based testing?
d. Thermostat Selection and Built-In Control Firmware
A key aspect of system performance addressed by load-based test
procedures is the way that the control system impacts the operation and
performance of the system. Since thermostats can vary in their control
algorithms and how they communicate with a system, the thermostat
selection can potentially impact the results of the test (see section
II.B.2.b of this RFI for further discussion). As noted in section
II.B.4.a, CSA EXP07 requires the make and model of the thermostat to be
recorded and reported with test data. The 4E IEA Project 2.0 round-
robin testing (described in section II.B.4.e of this RFI) is
investigating the impact of different thermostat selections on system
performance when subjected to the same test procedure using load-based
test conditions. DOE is not aware of data showing the variability of
test results when pairing the same CAC/CHP model with different
thermostats. However, as explained in section II.B.1, in response to a
notice of proposed rulemaking (``NOPR'') regarding CAC/HP test
procedures published on March 24, 2022 (``March 2022 CAC TP NOPR''),
NEEA provided data from a report \35\ that showed the seasonal
efficiency performance of variable-speed CAC/HPs
[[Page 4100]]
was highly dependent on the internal firmware of the system. 87 FR
16830.
---------------------------------------------------------------------------
\35\ The report is titled ``Heat Pump and Air Conditioner
Efficiency Ratings: Why Metrics Matter'', and can be downloaded for
free from this link: neea.org/resources/heat-pump-and-air-conditioner-efficiency-ratings-why-metrics-matter.
---------------------------------------------------------------------------
Issue 6: DOE requests comment on the impact of thermostat selection
and the built-in firmware version when testing CAC/HP under their
native controls. What range of performance could be measured using
different thermostats when testing the same system? How does this vary
for staged systems as compared with fully variable-speed systems? How
should thermostat pairings and the built-in firmware be considered from
a certification standpoint (i.e., should the thermostat used for
testing be certified as part of the tested combination)? DOE is also
interested in knowing how behavior of CAC/HPs in the field varies
depending on the thermostats pairing (i.e., those shipped with the unit
versus those obtained from third-party suppliers). DOE would like to
know what percentage of thermostats can be updated remotely via
firmware upgrades and what percentage can only be updated in the field
via service technicians.
e. Use of Different Test Methods for Different Purposes
It is DOE's understanding that some organizations seek to use load-
based testing as a tool to evaluate the performance of air conditioning
and heat pump systems even as the current regulatory test procedures
(e.g., appendix M1) are required for certification of compliance with
minimum efficient standards. As noted in section II.B.4.a, CSA EXP07
proposes to use test conditions that differ from the Federal test
procedures, which will yield different test results, whether or not
there might be inefficiencies that CSA EXP07 would capture that
conventional test methods do not.
Issue 7: DOE is interested in any existing examples of load-based
testing for regulatory purposes or for use in voluntary incentive-based
programs. Are there draft examples of how such regulation would be
applied, with focus on differences as compared with more conventional
test methods (e.g., appendix M1)?
f. Test Conditions for Load-Based Methods
Load-based test procedures for CAC/HPs may sometimes have test
conditions that do not align with the DOE test procedure outlined in
appendix M1. For example, EXP07 includes more test conditions spanning
a wider range of outdoor temperatures than appendix M1. Figure II-1 and
Table II-2 show a comparison of the test room conditions used in EXP07
versus the test conditions used in the DOE test procedure appendix M1.
[GRAPHIC] [TIFF OMITTED] TP24JA23.253
Table II-2--Comparison of Outdoor Dry-Bulb Temperature Test Conditions
Between EXP07 and DOE Test Procedure (Appendix M1) for CAC/HPs
------------------------------------------------------------------------
Cooling test conditions \1\ Heating test conditions \2\
------------------------------------------------------------------------
Appendix M1:
A2--95 [deg]F........................... H01--62 [deg]F.
Ev--87 [deg]F........................... H11/H12*/H1N/H1C1*--47
[deg]F.
B1 & B2--82 [deg]F...................... H2V/H22*--35 [deg]F.
F1/G1*/I1*--67 [deg]F................... H32--17 [deg]F.
H42*--5 [deg]F.
EXP07:
CA*--113 [deg]F......................... HA*--(-10 [deg]F).
CB--104 [deg]F.......................... HB*--5 [deg]F.
CC--95 [deg]F........................... HC--17 [deg]F.
CD--86 [deg]F........................... HD--34 [deg]F.
CE--77 [deg]F........................... HE--47 [deg]F.
HF--54 [deg]F.
------------------------------------------------------------------------
* Optional Test Condition.
\1\ Cooling-mode indoor room test condition temperatures are 80 [deg]F
dry-bulb, 67 [deg]F wet-bulb for appendix M1. EXP07 utilizes different
indoor room conditions based on humid climate (74 [deg]F dry-bulb, 63
[deg]F wet-bulb) and dry climate (79 [deg]F dry-bulb, 56 [deg]F wet-
bulb).
\2\ Heating-mode indoor room test condition temperatures are 70 [deg]F
dry-bulb, 60 [deg]F wet-bulb for both appendix M1 and for EXP07.
Issue 8: Given the differences between the EXP07 and appendix M1
test procedures for CAC/HPs, DOE requests information comparing how
rankings/ratings of CAC/HPs would differ when tested using the EXP07
test conditions (both outdoor and indoor) rather than the appendix M1
test conditions, keeping other aspects of the test the same. Further,
DOE requests comments on the relative benefits and drawbacks of
revising the appendix M1 test conditions.
g. Communicating and Non-Communicating Variable-Speed CAC/HP Systems
Controls used with CAC/HPs may transfer information between system
components, or they may use more conventional low-voltage on-off
signals to indicate ``calls'' for space conditioning and/or consumer
selection of fan settings. In the October 2022 CAC TP Final Rule, DOE
defined ``communicating control'' in the context of variable-speed
coil-only CAC/HPs to differentiate the test procedure provisions
applicable to communicating systems from those applicable to non-
communicating systems. 87 FR 16830, 16837. Section 1.2 of appendix M1
defines ``Communicating Variable-Speed Coil-Only Central Air
Conditioner or Heat Pump'' as follows:
Variable-Speed Communicating Coil-Only Central Air Conditioner or
Heat Pump means a variable-speed compressor system having a coil-only
indoor unit that is installed with a control system that (a)
communicates the difference in space temperature and space setpoint
temperature (not a setpoint value inferred from on/off thermostat
signals) to the control that sets compressor speed; (b) provides a
signal to the indoor fan to set fan speed appropriate for compressor
staging and air volume rate; and (c) has installation instructions
indicating that the required control system meeting both (a) and (b)
must be installed.
Although the DOE test procedure explicitly addresses communicating
vs. non-communicating operation only for coil-only variable-speed
systems, DOE is aware that there may also be non-communicating blower
coil variable-speed system installations. DOE understands that the
fundamental differences in the control architecture will lead to
performance differences. For example, a non-communicating
[[Page 4101]]
variable-speed system will not be able to apply classic proportional/
integral/differential control algorithms to minimizing space
temperature offset from setpoint, since the space thermostat would
generally only be able to indicate to the system whether there is a
need for conditioning and/or whether a call for a first or a second
level of conditioning should be engaged. Thus, it is unclear how such a
system would determine the appropriate level of variable-speed
compressor operation to engage to meet the conditioning load. It is
expected that there would be more variation of the capacity level of
such a system, operation which is known to affect efficiency. For
communicating variable-speed systems, it is clearer how the control
system would be able to set compressor operating level consistent and
better optimized for the conditioning need.
DOE is unaware if any of the load-based test methods have different
test procedure provisions for communicating and non-communicating CAC/
HPs, regardless of whether they are coil-only or blower coil systems.
Issue 9: DOE is interested in test data, if any, that shows how the
performance of communicating and non-communicating variable-speed CAC/
HPs compares when tested using load-based methods. For systems equipped
with non-communicating controls, DOE would like to know how load-based
methods address modulation of compressor speed for changing load and
outdoor conditions if the difference in indoor space temperature and
space setpoint temperature is not communicated to the control setting
compressor speed.
h. Load-Based Testing for Single-Stage and Two-Stage Variable-Speed
CAC/HP Systems
Much of the discussion about load-based testing has focused on
potential performance differences of variable-speed CAC/HP systems in
traditional fixed-setting testing as compared with load-based testing
methodologies that may better reflect field performance. However, the
potential application of load-based testing has also been discussed for
single-stage and two-stage CAC/HP systems. Appendix M1 does include
cyclic test procedures to capture the losses associated with compressor
cycling when capacity is greater than the load.\36\ But there may be
questions about whether this test is not sufficiently accurate or
whether there are other factors that might cause traditional test
methods to provide inaccurate indications of field performance.
---------------------------------------------------------------------------
\36\ Sections 3.5 and 3.8 of appendix M1 contain provisions for
conducting optional cooling and heating cyclic tests. These cyclic
tests are used to determine the Coefficient of Degradation
(CD), which is incorporated into the calculation of SEER2
and HSPF2, to account for any compressor cycling losses. If the
optional cyclic tests are not conducted, appendix M1 requires use of
the default CD value of 0.25. However, for the majority
of single- and two-stage systems, a lower CD can be
achieved when completing the optional cyclic tests, which results in
higher SEER2 and HSPF2.
---------------------------------------------------------------------------
Issue 10: DOE requests comment on the application of load-based
testing to single-stage and two-stage CAC/HP systems, specifically on
the differences between conventional test approaches and load-based
testing as indicators of system field performance. Additionally, DOE
requests any available information indicating whether the cyclic test
methods in appendix M1 may be unrepresentative in capturing cyclic
losses. Finally, DOE requests comment on whether there are other
aspects of single- and two-stage system operation that are not
adequately captured by the test methods of appendix M1.
i. Other Factors That Affect System Energy Use
The overall energy use of CAC/HP systems not only depends on how
long they operate in the cooling and/or heating seasons, but also on
aspects such as adaptive defrost systems, operation of electric
resistance heating elements, operation of the fan when the compressor
is not running (i.e., during the shoulder season) and operation of
auxiliary components during off-mode, such as crank case heaters. In
order to accurately capture the performance of CAC/HP systems while
testing in a laboratory for regulatory purposes, it is imperative that
a load-based test procedure should also account for the aforementioned
aspects.
Issue 11: DOE requests comment on the potential application of
load-based test procedure to other aspects of CAC/HP operation
affecting energy use, including but not limited to defrost systems,
operation of electric resistance heating elements (if equipped),
operation of fans when the compressor is not running during the
shoulder season, and operation of crank case heaters during off-mode.
C. Stakeholder Requests for Test Improvements in Appendix M1
As noted in section I.B, several stakeholder comments in the
October 2022 CAC TP final rule encouraged DOE to review ways to improve
the representativeness of the test procedures for CAC/HP in a future
rulemaking under DOE's 7-year lookback authority. Stakeholder requests
that relate to test procedure improvements in appendix M1 are discussed
in the subsequent sections.
1. Shoulder-Season Fan Power Consumption
In their written comments submitted during the rulemaking that
culminated in the October 2022 CAC TP final rule, the CA IOUs contended
that the current test procedure does not fully reflect energy use
during the shoulder-season hours when outdoor temperatures are
typically between 55 [deg]F and 64 [deg]F and the equipment is likely
in fan-only mode (i.e., the compressor is not running). (CA IOUs, No.
20 at pp. 2-3) CA IOUs further commented that the HSPF2 metric used for
evaluating heating operation in appendix M1 no longer includes
fractional bin hours when outdoor temperatures are between 55 [deg]F
and 64 [deg]F and that these hours represent approximately 24 percent
of the fractional bin hours relative to appendix M. Id.
In the October 2022 CAC TP Final Rule, DOE acknowledged the CA
IOUs' comment that shoulder-season fan energy consumption (i.e., fan
operation when there is no heating or cooling load) is not captured by
either the SEER/SEER2 or HSPF/HSPF2 metrics, which are constructed to
represent cooling season efficiency and heating season efficiency,
respectively.
DOE notes that a majority of CAC/HPs are installed in the field
with a furnace as the air mover (i.e., as coil-only CAC/HPs). Appendix
M1 specifies a default fan power for the testing of coil-only CAC/HPs
to represent the furnace fan use. The furnace fan test procedure (see
10 CFR part 430, subpart B, appendix AA (``appendix AA'')) addresses
fan energy use for cooling, heating, and constant circulation modes,
including constant circulation operation during the shoulder season.
Appendix AA uses an estimate of 400 hours as the national-average
annual hours of constant circulation fan operation (see 10 CFR part
430, subpart B, appendix AA, Table IV.2). The survey data used to
develop this estimate value is described in a furnace fan NOPR,
published on May 15, 2012. 77 FR 28674, 28682-28683. While the shoulder
season may include many hours when heating or cooling is not required,
the survey data and DOE's analysis suggest that only 9 percent of
systems operate in fan-only mode when no heating or cooling is being
provided, indicating that the shoulder-season fan energy consumption
may not be as significant as the CA IOUs present. (See,
[[Page 4102]]
e.g., Table III.1 in the furnace fan NOPR, 77 FR 28674, 28682). While
these hours are specifically associated with coil-only CAC/HP systems,
they may also be representative of blower coil systems, which are
excluded from the scope of appendix AA and covered in appendix M1. Key
factors that would make this energy use significant and worth
addressing include the constant circulation fan wattage of blower coil
systems, the percentage of such systems that use constant fan when not
in cooling and heating mode, and the average hours per year operating
in this mode for such a system.
Additionally, there is a potential of increased use of constant
circulation in systems that employ new refrigerants to mitigate
flammability risks. Currently, nearly all CAC/HP products are designed
with R-410A as the refrigerant. The EPA Significant New Alternatives
Policy (``SNAP'') Program evaluates and regulates substitutes for
ozone-depleting chemicals (such as CAC/HP refrigerants) that are being
phased out under the stratospheric ozone protection provisions of the
Clean Air Act. (42 U.S.C. 7401 et seq.) \37\ Of interest in this RFI,
the EPA SNAP Program's list of viable substitutes \38\ includes a group
of refrigerants classified as A2L refrigerants. A2L refrigerants
receive high attention for their low global warming potential in
addition to their minimal to zero ozone depletion potential. However,
A2L refrigerants also face stricter safety requirements than most due
to the flammability concerns associated with their ``2L'' ASHRAE safety
classification.\39\
---------------------------------------------------------------------------
\37\ Additional information regarding EPA's SNAP Program is
available online at: www.epa.gov/ozone/snap/.
\38\ List of EPA SNAP program-approved refrigerant substitutes
is available at: www.epa.gov/snap/substitutes-residential-and-light-commercial-air-conditioning-and-heat-pumps.
\39\ ASHRAE assigns safety classification to refrigerants based
on toxicity and flammability data. The capital letter designates a
toxicity class based on allowable exposure and the numeral denotes
flammability. For toxicity, Class A denotes refrigerants of lower
toxicity, and Class B denotes refrigerants of higher toxicity. For
flammability, class 1 denotes refrigerants that do not propagate a
flame when tested as per the standard; class 2 and 2L denotes
refrigerants of lower flammability; and class 3, for highly
flammable refrigerants such as the hydrocarbons.
---------------------------------------------------------------------------
Considering A2L flammability concerns and the large push towards
their increased use in design, UL recently published updated safety
standards \40\ for electrical heat pumps, air-conditioners, and
dehumidifiers that include the CAC/HP products at issue in this
document. One safety risk these standards address is refrigerant
leakage, which can be especially hazardous with A2Ls involved. In
satisfaction of new UL safety requirements, manufacturers may need to
adjust CAC/HP product design to include refrigerant leak detection
systems, which use sensors and control logic to detect a loss of
pressure, activate the evaporator fan, and use circulated air to
quickly disperse and dilute refrigerant in the event of a leakage. DOE
acknowledges that a subsequent need may exist for the constant
circulation of refrigerant or circulation based on leak detection to
accommodate these refrigerant leak detection and mitigation strategies
in CAC/HP product design.
---------------------------------------------------------------------------
\40\ On November 1, 2019, UL published an updated 3rd edition of
UL 60335-2-40 that includes safety requirements regarding the use
A2L refrigerants in CAC/HP product design.
---------------------------------------------------------------------------
Issue 12: DOE requests information on the typical fan power for
constant circulation mode for blower coil systems (or as a fraction of
cooling or heating fan power); whether constant circulation mode is a
default or user configurable setting for these systems and whether
manufacturers plan to modify this as part of their mitigation strategy
for refrigerant leakage; and information on the percentage of people
that use this mode and the associated hours per year on average the
system would be in this mode.
Issue 13: DOE requests comment on whether measurement of SEER2 and/
or HSPF2 should take into consideration that a certain fraction of
systems will use constant circulation mode rather than turn off the fan
during the compressor off mode.
Issue 14: DOE requests comment on whether UL safety requirements
for A2L refrigerants will require some level of circulation on a
continuous basis, or whether circulation to disperse refrigerant will
only be required when sensors detect a leak. DOE is interested to know
of any other techniques that manufacturers will use for dispersing the
A2L refrigerant in the event of a refrigerant leak.
2. Power Consumption of Auxiliary Components
In comments submitted during the rulemaking that culminated in the
October 2022 CAC TP final rule, the CA IOUs also commented that neither
the HSPF2 nor the SEER2 metrics reflect the energy use of auxiliary
components, including fans and crankcase heaters, when the compressor
is off, and the SEER2 and HSPF2 metrics therefore do not fully
represent any difference in the efficiency of auxiliary equipment
between systems. (CA IOUs, No. 20 at pp. 2-3) They recommended that DOE
consider methods to address these energy uses in a subsequent review of
test procedure. Id.
DOE notes that there are already test procedures and energy
conservation standards governing the allowable off-mode power
consumption for CAC/HPs, which encapsulates the off-mode and standby
power consumed by auxiliary components such as crankcase heaters as
suggested by the CA IOUs. These test procedures are enumerated in
section 4.3 of appendix M and appendix M1, and standards are enumerated
at 10 CFR 430.32(c)(4). DOE acknowledges the CA IOUs' comment that the
energy use of crankcase heaters is not directly included \41\ in the
SEER2 and HSPF2 metrics but notes that this energy use is accounted for
in off-mode power. In a NOPR regarding CAC/HP test procedures published
on June 2, 2010 (``June 2010 CAC TP NOPR''), DOE noted that integrating
off-mode energy use, and hence crankcase heater energy use, into SEER
and HSPF metrics, would not be technically feasible because they both
are seasonal descriptors. 75 FR 31224, 31239. Using these two seasonal
metrics to account for out-of-season off-mode energy consumption (i.e.,
the energy consumed during the shoulder season and during the heating
season) would be inconsistent with the definitions of SEER and HSPF.
Id. Hence, in order to maintain the technical integrity of SEER and
HSPF and to account for off-mode energy consumption, DOE developed a
separate algorithm to calculate the off-mode (off-season) energy
consumption.\42\ Id. Nevertheless, to help DOE further assess whether
its test procedure adequately addresses crankcase heater energy use,
DOE is requesting information and data from stakeholders.
---------------------------------------------------------------------------
\41\ Some energy use associated with crankcase heaters is
inherently measured in the cyclic cooling (for non-temperature
dependent crankcase heaters) and cyclic heating tests in appendix
M1.
\42\ The calculation of off-mode power consumption is explained
in section 3.13 of appendix M, and section 4.3 of appendix M1.
---------------------------------------------------------------------------
Issue 15: DOE requests information as to what percentage of units
on the market (split separately between air-conditioners and heat
pumps) are shipped from the factory with crank-case heaters; what
percentage have crank-case heaters installed in the field (e.g., by
contractors); and the percentage breakdown of controls used with units
(both factory- and field-installed)--by those that are energized at
full power during the compressor off cycle, those that also have an
ambient thermostat to prevent use when temperature is high, and those
that are self-regulating.
[[Page 4103]]
Issue 16: DOE requests information and available field data, on any
other auxiliary components that come equipped with CAC/HPs that use
energy or affect system energy use.
In a supplemental notice of proposed rulemaking (``SNOPR'')
regarding CAC/HP test procedures published on August 24, 2016, DOE
revised the off-mode test procedure by imposing time delays to allow
self-regulating crankcase heaters to approach equilibrium. 81 FR 58163,
58173-58174 (``August 2016 CAC TP SNOPR''). Specifically, DOE proposed
a 4-hour time delay for units without compressor sound blankets and an
8-hour time delay for units with compressor sound blankets. Id. DOE
proposed these time delays based on testing of a 5-ton residential
condensing unit. Id. In response to stakeholder comments regarding the
aforementioned time delays, DOE decided in the January 2017 CAC TP
final rule to adopt the proposed time delays for measurements of off-
mode power for units with self-regulating crankcase heaters or heater
systems in which the crankcase heater control is affected by the
heater's heat, in appendix M1, but not appendix M. 82 FR 1426, 1438.
Nevertheless, DOE acknowledges that with more test procedure
development time, an approach could potentially be developed that would
allow for accurate projections of self-regulating crankcase heater
energy use to be determined in reduced time and requests comment on
this possibility.
Issue 17: DOE requests test data that would indicate if and how the
4-hour time delay (for compressors without sound blankets) and 8-hour
time delay (for compressors with sound blankets) may be reduced, for
units with self-regulating crankcase heaters, without compromising the
accuracy of the off-mode power consumption measurement.
3. Low-Temperature Heating Performance
In the previous CAC/HP test procedure rulemaking, NYSERDA
encouraged DOE to start immediately on foundational work needed to
improve the standard and test procedure to better account for equipment
performance in cold climates. (NYSERDA, No. 17 at pp. 2-3) NYSERDA
requested that DOE make the H4, H42, or H43
heating tests in appendix M1 mandatory in order to produce more
representative ratings that account for system performance at 5 [deg]F.
Id. NYSERDA also requested that DOE explore how to test and report
relative capacity maintenance at temperatures lower than the heating
mode test temperatures that are used to determine nominal capacity and
suggested that DOE prescribe performance requirements of low-
temperature capacity maintenance for products advertised as cold-
climate heat pumps. Id. Further, NYSERDA requested that DOE evaluate
how a variety of sizing approaches could be incorporated into the test
procedure. Id. NYSERDA highlighted that DOE has previously established
that the sizing assumptions inherent in the DOE test procedure are
based on cooling capacity and provide an example of a sizing and
selection guide that emphasizes heating function. Id.
While the H4 heating tests provide meaningful information and more
representative ratings for products designed specifically for low
temperature operation, appendix M1 includes them as optional tests, as
they may not be appropriate for all CHPs. Currently, appendix M1 allows
the performance at 5 [deg]F to be extrapolated based on tests conducted
at 17 [deg]F and 47 [deg]F (i.e. using the H32 and
H12 tests, respectively) for CHPs that are not tested at the
H4 heating condition. While the ENERGY STAR certification is a
voluntary program, DOE notes that the latest ENERGY STAR specification
for CAC/HPs \43\ already has cold-climate performance and capacity
maintenance requirements as suggested by NYSERDA.
---------------------------------------------------------------------------
\43\ Version 6.1 of the ENERGY STAR specification for CAC/HPs,
revised in January 2022, can be found here: www.energystar.gov/products/spec/central_air_conditioner_and_air_source_heat_pump_specification_version_6_0_pd.
---------------------------------------------------------------------------
In the August 2016 CAC TP SNOPR, DOE noted that most heat pump
units in the field are sized based on cooling capacity as opposed to
heat pump capacity, consistent with ACCA Manual S provisions. 81 FR
58163, 58188. Subsequently, in the January 2017 CAC TP final rule, DOE
revised appendix M1 such that the determination of the heating load
line was based on cooling capacity rather than heating capacity. 82 FR
1426,1453-1454. Part of DOE's motivation for this change was that the
previous approach of heating load line determination based on the
nominal heating capacity (H1N capacity) provided little incentive to
design for good heat pump performance, since low H1N capacity resulted
in a low load line and generally better HSPF. Sizing based on cooling
capacity is consistent with trends for sales distributions of heat
pumps, which have had greater adoption in milder climates than cold
climates.\44\ However, DOE is aware that NRCan has proposed
alternatives for sizing CAC/HPs, in its ``Air Source Heat Pump Sizing
and Selection Guide'',\45\ which provides four different approaches
with varying emphasis on heating vs. cooling, ranging from sizing based
on cooling to sizing such that the heat pump can meet the design
heating load without need for resistance auxiliary heat. DOE
acknowledges that in cold climates, sizing a heat pump for heating may
be more appropriate than sizing for cooling. Further, DOE acknowledges
that accurate information regarding heat pump cold-weather performance
is relevant for selection of the best heat pumps for cold climates.
Nevertheless, it is not clear how a test procedure using a heating load
line based on heating performance would incentivize good heating
performance, particularly if it is based on heating performance at 47
[deg]F, which is not a heating design temperature. As mentioned
earlier, this is the same issue that led DOE to move to the cooling-
capacity-based load line in appendix M1. Further, given the greater
market share in milder climates, it is unclear that requiring a 5
[deg]F test is appropriate for all heat pump models.
---------------------------------------------------------------------------
\44\ RECS 2020 data shows that electric heat pumps represent 29%
of primary space heating equipment in homes in the South region,
which is a higher number as compared to the 14% for US overall. See:
www.eia.gov/consumption/residential/data/2020/hc/pdf/HC%206.8.pdf.
\45\ The ``Air Source Heat Pump Sizing and Selection Guide'' was
written by NRCan in response to stakeholder requests for consistent
guidance for sizing ASHPs according to the design heating or cooling
load and intended use as well as identifying the appropriate system
according to the installation and application. The four methods of
sizing in the Guide are Options 4A (Emphasis on Cooling), 4B
(Balanced Heating and Cooling), 4C (Emphasis on Heating) and 4D
(Sized on Design Heating Load). The ``Air Source Heat Pump Sizing
and Selection Guide'' is available here: publications.gc.ca/collections/collection_2021/rncan-nrcan/M154-138-2020-eng.pdf.
---------------------------------------------------------------------------
Issue 18: DOE requests comment on whether it would be appropriate
to make the H4 heating tests mandatory for all CHPs. If not for all
CHPs, DOE requests comment on whether it would be appropriate to make
the tests mandatory for any subset of CHPs, e.g., cold climate heat
pumps, and if so, what characteristics would represent a clear
delineation to distinguish such models from others. DOE also seeks
information on the prevalence of test chambers capable of testing CHPs
at outdoor ambient temperature of 5 [deg]F.
Issue 19: Further, DOE requests comment on whether the test
procedure for such cold climate heat pumps should use a heating load
line based on heating performance, and how such an approach could be
implemented such that it does not weaken the incentive for good cold-
temperature heating performance.
[[Page 4104]]
D. Additional Improvements in Appendix M1
In addition to the potential improvements in appendix M1 suggested
by stakeholders in previous rulemakings, DOE is also considering
potential improvements to address issues and questions that have come
to light as part of DOE testing of CAC/HPs, industry technical
committee discussions, and other discussions with stakeholders.
1. Impact of Defrost on Performance
Defrost is required for heat pumps when operating in moderate to
low outdoor temperatures when the outdoor coil surface temperature is
sufficiently low to freeze moisture removed from the air or
precipitation that can collect on the coil. For defrost, the system
switches back to cooling mode operation in which heat is transferred
from the indoor coil to the outdoor coil to provide the heat to warm
the coil and melt the frost. During defrost, different control
strategies are applied to maintain comfort level inside the house. For
example, the indoor fan may or may not be operated during defrost, and
(if the indoor fan is operated) the auxiliary resistance heater may or
may not be energized to warm the indoor air while the system is
temporarily in defrost mode. Defrost initiation can be based on time
(clock time or time of compressor operation), or the need for defrost
can be determined based on temperature and pressure or other
measurements that provide an indication of the need for defrost.\46\
Appendix M1 defines a demand-defrost control system as a system that
defrosts the heat pump outdoor coil only when measuring a predetermined
degradation of performance. When frequent defrost occurrences are not
needed, e.g. when there is insufficient moisture in the outdoor air to
build up a significant frost layer on the outdoor coil, demand defrost
can save energy by delaying defrost initiation. Defrost cycles are
terminated when there is indication that defrost has been long enough
for frost to be eliminated from the coil, e.g., when a coil temperature
sensor indicates the coil is well above 32 [deg]F.
---------------------------------------------------------------------------
\46\ Some examples of parameters monitored for demand-defrost
control systems are coil to air differential temperature, coil
differential air pressure, outdoor fan power or current, optical
sensors. Note that systems that vary defrost intervals according to
outdoor dry-bulb temperature are not demand-defrost systems.
---------------------------------------------------------------------------
For CAC/HPs equipped with demand defrost, appendix M1 includes a
term called the demand defrost credit (``Fdef'') in the
HSPF2 calculation to provide nominal credit for heat pumps with a
demand-defrost control system, reflecting the relative improvement in
heating mode efficiency due to use of demand defrost rather than
defrosts with fixed periodicity. The demand-defrost credit, first
introduced in a March 14, 1988, rulemaking (53 FR 8304, 8319), is
calculated by the following equation in section 3.9.2 of appendix
[GRAPHIC] [TIFF OMITTED] TP24JA23.254
where [Delta][tau]def = time between defrost terminations (in hours) or
1.5, whichever is greater. [Delta][tau]def is assigned a value of 6 if
this limit is reached during a frost accumulation test and the heat
pump has not completed a defrost cycle, and [Delta][tau]max= maximum
time between defrosts as allowed by the controls (in hours) or 12,
whichever is less, as provided in the certification report.
The credit equation has remained unchanged in its current form in
the test procedure since at least January 22, 2001, when DOE published
a NOPR. 66 FR 6767. Based on the test results of several CAC/HPs in
various programs, DOE has noticed a range of defrost operation
sequences and a range of approaches to defrost initiation for demand
defrost. Based on these observations, DOE acknowledges that the demand
defrost credit may no longer accurately reflect the benefits of demand
defrost.
Issue 20: DOE seeks information on the operation of demand-defrost
control systems, specifically information that would indicate whether
the demand-defrost credit outlined in the calculation in section 3.9.2
of appendix M1 is representative of the improvement in seasonal heating
efficiency in field operation. Further, DOE requests comment whether
any specific change in the credit equation could improve its accuracy.
Appendix M1 requires that CHPs undergo a test at 35 [deg]F dry-bulb
temperature and 33 [deg]F wet-bulb temperature, a condition for which
frost accumulation is rapid, generally affecting performance before a
30-minute steady-state test can be completed. For this condition, the
test procedure prescribes use of a transient test, including a frost
accumulation period followed by defrost. Capacity and power input for
the test are averaged for a full cycle of heating followed by defrost.
At this condition, appendix M1 estimates the average capacity is 10
percent lower (or more) than it would be if there were no frost
accumulation, while average power may be just slightly lower, thus
reducing efficiency. At temperatures between 17 [deg]F and 45 [deg]F,
the performance calculations prescribed in the test procedure call for
representing capacity as a linear function of temperature based on the
tests conducted at 17 [deg]F and 35 [deg]F--likewise for power input.
Hence, the frost/defrost impact is built into the HSPF2 calculation for
temperatures in this range. The DOE test procedure requires use of the
35 [deg]F test for single-stage and two-stage CHPs for all capacity
levels. However, for variable-speed CHPs, the test procedure requires
the defrost test be conducted only at intermediate compressor speed,
and performance is estimated using default degradation factors at full
capacity (see section 3.6.4.1.c of appendix M1).
In testing, DOE has observed variations among CHP models in regard
to defrost control (e.g., time durations of the defrost can vary
significantly for different models, and the indoor unit fan shuts off
during defrost for some units but not all). In addition, as part of the
DOE CCHP Tech Challenge, DOE has tested systems with electric
resistance heaters and noted that resistance heater operation during
defrost can vary significantly for different models. This varying
behavior clearly affects energy use, and while some aspects of which
may be captured by the current appendix M1 test procedure, others may
not be.
Issue 21: DOE requests information regarding defrost impact on
heating capacity and power input over a range of temperatures to inform
evaluation of whether the approach used in the DOE test procedure to
account for this impact is accurate or whether it could be improved by
revision.
[[Page 4105]]
2. Inlet Duct Design for Accurate Measurement With Minimal Length
In a final rule regarding CAC/HP test procedures published on June
8, 2016 (``June 2016 CAC TP final rule''), DOE made clarifications on
the indoor unit air inlet geometry and made a revision to ensure that
the inlet plenum is not installed upstream of the airflow prevention
device, and that the minimum lengths of inlet plenum, locations of
static-pressure taps, and minimum cross-sectional dimensions are
consistent with American National Standards Institute (``ANSI'')/ASHRAE
Standard 37-2009 (``ANSI/ASHRAE 37-2009''), Methods of Testing for
Rating Electrically Driven Unitary Air-Conditioning and Heat Pump
Equipment. 81 FR 36991, 37037. DOE also clarified that when an inlet
plenum is not used, then the length of straight duct upstream of the
unit's inlet within the airflow prevention device must still adhere to
the inlet plenum length requirements as illustrated in ANSI/ASHRAE 37-
2009, figures 7b, 7c, and 8. Id.
In response, AHRI and Nortek commented that DOE's clarification of
inlet plenum may result in the overall height of unit setup exceeding
the current height limit of many existing psychrometric rooms. 82 FR
1426, 1463. They proposed that DOE should consider allowing the
approach included in ASHRAE's RP 1581, requesting DOE to approve the
use of the 6'' skirt coupled with the 90[deg] square vane elbow, along
with the appropriate leaving duct. Id. At the time of the January 2017
CAC TP Final Rule, the ASHRAE Standards Policy Committee had not added
the details of RP 1581 into ASHRAE Standard 37, and hence DOE did not
modify its requirement laid out in the January 2016 CAC TP Final Rule.
However, DOE is aware that these details may be part of the upcoming
edition of ASHRAE Standard 37.
Issue 22: DOE seeks test data that shows testing done using reduced
overall height of the unit setup (similar to that proposed in ASHRAE RP
1581) and compared against the baseline duct designs in ASHRAE 37-2009
Figures 7(b) and 7(c) for blower coil indoor units, and Figure 8 for
coil-only indoor units. DOE requests information that could help inform
the existing CAC/HP test procedures to allow testing in smaller
environmental chambers, or to incorporate adjustments to the test setup
that might reduce test burden.
3. Heat Comfort Controllers
A heat comfort controller enables a heat pump to regulate the
operation of the electric resistance elements such that the air
temperature leaving the indoor section does not fall below a specified
temperature (see appendix M1). Appendix M1 notes that heat pumps that
actively regulate the rate of electric resistance heating when the
controls indicate heat pump capacity at the given outdoor temperature
is insufficient to meet the load (e.g., through higher-stage calls from
the thermostat), but do not operate to maintain a minimum delivery
temperature, are not considered as having a heat comfort controller.
Section 3.6.5 of appendix M1 includes test instructions for testing
heat pumps having a heat comfort controller. However, DOE understands
that the heat comfort controller option may no longer be prevalent in
contemporary CHP systems.
Issue 23: DOE requests information on the prevalence of CHP systems
that include heat comfort controllers. DOE requests feedback on whether
the heat comfort controller test approach in appendix M1 is utilized by
manufacturers, and if yes, whether it needs to be updated.
4. Cut-Out and Cut-In Temperature Certification
The calculation of HSPF2 in appendix M1 requires values for cut-out
\47\ and cut-in \48\ temperatures (see, e.g., equation 4.2.1-3 in
section 4.2 of appendix M1). For CAC/HPs that do not include the cut-
out and cut-in temperatures in their installation manuals, the
manufacturer (or DOE, in case of compliance testing) must provide the
test lab with this information. DOE's lab testing suggests that
manufacturers often use cut-out and cut-in temperatures in their HSPF2
calculations that are much lower than can be reasonably expected in the
field--in some instances as low as -40 [deg]F. However, a review of
product literature for scroll compressors with model numbers Copeland
ZP*3KE and ZP*5KE R410A (typically used in CAC/HPs) shows that the
lowest refrigerant evaporating temperature of these systems is no lower
than -10 [deg]F.\49\
---------------------------------------------------------------------------
\47\ Cut-out temperature refers to the outdoor temperature at
which the unit compressor stops (cuts out) operation.
\48\ Cut-out temperature refers to the outdoor temperature at
which the unit compressor stops (cuts out) operation.
\49\ Figure 7 in the operating bulletin of the Copeland ZP*3KE
and ZP*5KE R410A scroll compressors shows their evaporating
envelope, clearly indicating that they should not be used below
saturated suction temperatures of -10 [deg]F, implying that this
should be set as the cut-out temperature. The bulletin is available
here climate.emerson.com/documents/ae-1331-zp16-to-zp44k3e-zp14-to-zp61k5e-r-410a-1-5-to-5-ton-copeland-scroll-compressors-en-us-1571048.pdf.
---------------------------------------------------------------------------
DOE has also found in testing that the ambient temperatures at
which the control cuts out and cuts in may be significantly different
than the control's specified temperatures. This can be due to control
component manufacturing variation. However, it can also be due to
sensors being located where temperature deviates from that of the
ambient air--this can occur downstream of the outdoor coil, which
absorbs heat from the ambient air during heat pump operation.
Issue 24: DOE requests information on the range of cut-out
temperatures for compressor operation of CAC/HPs.
5. Extending the Definition of Low-Static Blower-Coil Systems to
Single-Split Systems
Section 3.1.4.1.1 of appendix M1 defines the minimum external
static pressure (``ESP'') for ducted blower coil systems in Table 4.
For conventional blower coil systems (i.e., all CAC/HPs that are not
classified as ceiling-mount, wall-mount, mobile home, low-static, mid-
static, small-duct high-velocity (``SDHV''), or space-constrained), the
minimum ESP is specified as 0.5 inches of water column (``w.c.''). The
definition for low-static blower-coil systems includes only multi-split
and multi-head mini-split systems--it does not include single-split
systems. In response to the March 2022 CAC TP NOPR, DOE received
multiple comments concerning the 0.5 inches w.c. minimum ESP. AHRI and
Samsung commented that currently, appendix M1 does not allow testing of
low-static single-zone \50\ units and requested that the low-static
blower coil system definition be expanded to include products that
cannot accommodate the 0.5 inches w.c. necessary for testing. (AHRI,
No.25 at p. 7, Samsung, No.22 at pp. 2-3)
---------------------------------------------------------------------------
\50\ The comments used the term ``single-zone'', which is
addressed by the term ``single-split'' in appendix M1.
---------------------------------------------------------------------------
In the October 2022 CAC TP final rule, DOE did not revise the
definition for low-static blower coil systems, nor did it include any
new test provisions to accommodate these system types. DOE presented
evidence from the November 2015 SNOPR (80 FR 74020, 69355), 2016 CAC
Term Sheet (see 2016 CAC Term Sheet: Docket No. EERE-2014-BT-STD-0048,
No. 76), and the August 2016 CAC TP SNOPR (81 FR 58163) public meeting
\51\ to indicate that stakeholders had rejected DOE's proposal to
establish a ``short-ducted''
[[Page 4106]]
product class, and a majority of them expressed support for the new
minimum ESP requirements that DOE had proposed, including the 0.5
inches w.c. ESP requirement generally applicable to single-split
systems. Thus, DOE believed that revising the definition of low-static
blower coil systems, as suggested by Samsung and AHRI, would conflict
with the intent of the stakeholders' comments when establishing
appendix M1, and could potentially create an unfair competitive
advantage for such systems by allowing more lenient testing conditions
(and thus comparatively higher ratings) as compared to conventional
centrally ducted systems tested at minimum ESPs exceeding 0.50 inches
w.c. Rather than granting test procedure waivers to allow such models
to test using lower ESP, DOE considers it more appropriate to revisit
the issue in a test procedure rulemaking. Thus, DOE is soliciting
feedback on this issue.
---------------------------------------------------------------------------
\51\ See www.regulations.gov Docket No. EERE-2016-BT-TP-0029,
No. 20 for the transcript of the August 2016 CAC TP SNOPR public
meeting.
---------------------------------------------------------------------------
Issue 25: DOE requests comment from stakeholders on whether the
low-static blower-coil system definition should be extended to single-
split systems, and if extended, how these low-static blower-coil
systems will be differentiated from conventional systems.
6. Hybrid Heat Pumps
Heat pumps generally perform less efficiently at low ambient
outdoor temperatures than they do at moderate ambient outdoor
temperatures. DOE is aware of CHPs that combine the operation of a
conventional electric CHP with a back-up heating source, such as a
fuel-fired furnace or boiler. These are referred to as ``dual-fuel'' or
hybrid heat pumps (``HHPs'') and provide an alternative to heat pumps
specifically designed to perform in cold climates (i.e., cold climate
heat pumps). HHPs rely on heat pump operation at milder ambient
temperatures, but switch to the back-up heating source at low ambient
temperatures, thereby optimizing for energy cost and comfort.
Currently, the HSPF2 calculation at appendix M1 does not differ for
a HHP and heat pumps that rely solely on vapor-compression or electric
resistance auxiliary heating. However, this may not be representative
of HHP field operation since the back-up heating source takes over for
much of the coldest conditions when heat pump efficiency would be
lower. While the focus of test procedures for cold climate heat pumps
has been on evaluation of performance at colder temperatures (e.g. the
optional 5 [deg]F test condition) to incentivize improved cold-
temperature performance, incentivizing efficiency improvement for HHPs
might more appropriately focus on warmer conditions, potentially
temperatures warmer than 17 [deg]F.
Issue 26: DOE requests information on the prevalence of HHP systems
(including shipment numbers and shipment breakdown among single-stage,
two-stage and variable-capacity) and the climates they are most used
in. DOE requests information on how the controls for HHPs are generally
set up to provide dual functionality--specifically, whether the furnace
is just set at a higher stage, or whether there is a crossover
temperature below which the CHP isn't used, if so, the range of
crossover temperatures; and whether these systems have electric
resistance auxiliary heaters. DOE requests feedback on whether it is
more appropriate to adjust the HSPF2 to address actual operation of the
heat pump or just to emphasize performance only in heat pump mode
(i.e., when the back-up source is not operating).
III. Submission of Comments
DOE invites all interested parties to submit in writing by the date
specified under the DATES heading, comments and information on matters
addressed in this RFI and on other matters relevant to DOE's
consideration of amended test procedures for CAC/HPs. These comments
and information will aid in the development of a test procedure NOPR
for CAC/HPs if DOE determines that amended test procedures may be
appropriate for these products.
Submitting comments via www.regulations.gov. The
www.regulations.gov web page will require you to provide your name and
contact information. Your contact information will be viewable to DOE
Building Technologies staff only. Your contact information will not be
publicly viewable except for your first and last names, organization
name (if any), and submitter representative name (if any). If your
comment is not processed properly because of technical difficulties,
DOE will use this information to contact you. If DOE cannot read your
comment due to technical difficulties and cannot contact you for
clarification, DOE may not be able to consider your comment.
However, your contact information will be publicly viewable if you
include it in the comment or in any documents attached to your comment.
Any information that you do not want to be publicly viewable should not
be included in your comment, nor in any document attached to your
comment. Following this instruction, persons viewing comments will see
only first and last names, organization names, correspondence
containing comments, and any documents submitted with the comments.
Do not submit to www.regulations.gov information for which
disclosure is restricted by statute, such as trade secrets and
commercial or financial information (hereinafter referred to as
Confidential Business Information (``CBI'')). Comments submitted
through www.regulations.gov cannot be claimed as CBI. Comments received
through the website will waive any CBI claims for the information
submitted. For information on submitting CBI, see the Confidential
Business Information section.
DOE processes submissions made through www.regulations.gov before
posting. Normally, comments will be posted within a few days of being
submitted. However, if large volumes of comments are being processed
simultaneously, your comment may not be viewable for up to several
weeks. Please keep the comment tracking number that www.regulations.gov
provides after you have successfully uploaded your comment.
Submitting comments via email, hand delivery/courier, or postal
mail. Comments and documents submitted via email, hand delivery/
courier, or postal mail also will be posted to www.regulations.gov. If
you do not want your personal contact information to be publicly
viewable, do not include it in your comment or any accompanying
documents. Instead, provide your contact information on a cover letter.
Include your first and last names, email address, telephone number, and
optional mailing address. The cover letter will not be publicly
viewable as long as it does not include any comments.
Include contact information each time you submit comments, data,
documents, and other information to DOE. If you submit via postal mail
or hand delivery/courier, please provide all items on a CD, if
feasible, in which case it is not necessary to submit printed copies.
Faxes will not be accepted.
Comments, data, and other information submitted to DOE
electronically should be provided in PDF (preferred), Microsoft Word or
Excel, WordPerfect, or text (ASCII) file format. Provide documents that
are not secured, written in English and free of any defects or viruses.
Documents should not contain special characters or any form of
encryption and, if possible, they should carry the electronic signature
of the author.
Campaign form letters. Please submit campaign form letters by the
originating organization in batches of between 50 to
[[Page 4107]]
500 form letters per PDF or as one form letter with a list of
supporters' names compiled into one or more PDFs. This reduces comment
processing and posting time.
Confidential Business Information. 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 via
email two well-marked copies: one copy of the document marked
confidential including all the information believed to be confidential,
and one copy of the document marked ``non-confidential'' with the
information believed to be confidential deleted. DOE will make its own
determination about the confidential status of the information and
treat it according to its determination.
It is DOE's policy that all comments may be included in the public
docket, without change and as received, including any personal
information provided in the comments (except information deemed to be
exempt from public disclosure).
DOE considers public participation to be a very important part of
the process for developing test procedures and energy conservation
standards. DOE actively encourages the participation and interaction of
the public during the comment period in each stage of this process.
Interactions with and between members of the public provide a balanced
discussion of the issues and assist DOE in the process. Anyone who
wishes to be added to the DOE mailing list to receive future notices
and information about this process should contact Appliance and
Equipment Standards Program staff at (202) 287-1445 or via email at
[email protected]">ApplianceStandards[email protected].
Signing Authority
This document of the Department of Energy was signed on January 12,
2023, by Francisco Alejandro Moreno, Acting Assistant Secretary for
Energy Efficiency and Renewable Energy, pursuant to delegated authority
from the Secretary of Energy. That document with the original signature
and date is maintained by DOE. For administrative purposes only, and in
compliance with requirements of the Office of the Federal Register, the
undersigned DOE Federal Register Liaison Officer has been authorized to
sign and submit the document in electronic format for publication, as
an official document of the Department of Energy. This administrative
process in no way alters the legal effect of this document upon
publication in the Federal Register.
Signed in Washington, DC, on January 12, 2023.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.
[FR Doc. 2023-00942 Filed 1-23-23; 8:45 am]
BILLING CODE 6450-01-P