[Federal Register Volume 76, Number 197 (Wednesday, October 12, 2011)]
[Proposed Rules]
[Pages 63211-63216]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-25815]


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DEPARTMENT OF ENERGY

10 CFR Part 430

[Docket Number EERE-2011-BT-TP-0042]
RIN 1904-AC53


Energy Efficiency Program: Test Procedures for Residential Water 
Heaters, Direct Heating Equipment, and Pool Heaters

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of 
Energy.

ACTION: Request for information.

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SUMMARY: Through this Request for Information (RFI), the U.S. 
Department of Energy (DOE) is initiating a rulemaking and data 
collection process to consider amendments to DOE's test procedures for 
residential water heaters, direct heating equipment, and pool heaters. 
This rulemaking is intended to fulfill DOE's statutory obligation to 
review its test procedures for covered products at least once every 
seven years. To inform interested parties and to facilitate the 
process, DOE has gathered data and has identified several issues that 
might warrant modifications to the current applicable test procedures, 
including topics on which DOE is particularly interested in receiving 
comment. In overview, the issues outlined in this document mainly 
concern the scope, draw patterns, and test conditions for residential 
water heaters, possible clarifications and improvement of the direct 
heating equipment test procedures as applied to vented hearth heaters, 
and coverage of electric pool heaters. Additionally, this RFI briefly 
discusses and seeks input on certain potential changes to the test 
procedures for these products that DOE anticipates may be included in a 
subsequent notice of proposed rulemaking (NOPR). DOE welcomes written 
comments from the public on any subject related to the test procedures 
for residential heating products (including topics not specifically 
raised in this RFI).

DATES: Written comments and information are requested on or before 
November 28, 2011.

ADDRESSES: Interested persons are encouraged to submit comments using 
the Federal eRulemaking Portal at http://www.regulations.gov. Follow 
the instructions for submitting comments. Alternatively, interested 
persons may submit comments, identified by docket number EERE-2011-BT-
TP-0042 and/or RIN 1904-AC53, by any of the following methods:
     E-mail: [email protected]. Include 
EERE-2011-BT-TP-0042 and/or RIN 1904-AC53 in the subject line of the 
message. Submit electronic comments in WordPerfect, Microsoft Word, 
PDF, or ASCII file format, and avoid the use of special characters or 
any form of encryption.
     Postal Mail: Ms. Brenda Edwards, U.S. Department of 
Energy, Building Technologies Program, Mailstop EE-2J, 1000 
Independence Avenue, SW., Washington, DC 20585- 0121. Telephone: (202) 
586-2945. 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: Ms. Brenda Edwards, U.S. Department 
of Energy, Building Technologies Program, 950 L'Enfant Plaza, SW., 6th 
Floor, Washington, DC 20024. Telephone: (202) 586-2945. If possible, 
please submit all items on a CD, in which case it is not necessary to 
include printed copies.
    All submissions received must include the agency name and docket 
number and/or RIN for this rulemaking. No telefacsimilies (faxes) will 
be accepted. For detailed instructions on submitting comments and 
additional information on the rulemaking process, see section III of 
this document (Public Participation).
    Docket: For access to the docket to read background documents or 
comments received, go to the Federal eRulemaking Portal at http://www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: Requests for additional information 
may be sent to Mr. Mohammed Khan, U.S. Department of Energy, Office of 
Energy Efficiency and Renewable Energy, Building Technologies Program, 
Mailstop EE-2J, 1000 Independence Avenue, SW., Washington, DC 20585-
0121. Telephone: (202) 586-7892. E-mail: [email protected].
    Mr. Eric Stas, U.S. Department of Energy, Office of the General 
Counsel, Mailstop GC-71, 1000 Independence Avenue, SW., Washington, DC 
20585-0121. Telephone: (202) 586-9507. E-mail: [email protected].
    For information on how to submit or review public comments, contact 
Ms. Brenda Edwards, U.S. Department of Energy, Office of Energy 
Efficiency and Renewable Energy, Building Technologies Program, EE-2J, 
1000 Independence Avenue, SW., Washington, DC 20585-0121. Telephone: 
(202) 586-2945. E-mail: [email protected].

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Authority and Background
II. Discussion
    A. Test Procedure for Residential Water Heaters
    1. Scope
    a. Water Heaters With Storage Volumes Between 2 Gallons (7.6 L) 
and 20 Gallons (76 L)
    b. Electric Instantaneous Water Heaters
    c. Storage Water Heaters With Very Large Storage Capacities
    2. Draw Pattern
    3. Discrete Performance Tests
    4. Test Conditions
    a. Water Delivery Temperature
    b. Ambient Temperature and Relative Humidity
    5. Other Issues
    B. Test Procedure for Direct Heating Equipment
    1. Vented Hearth Heaters
    2. Other Issues
    C. Test Procedure for Pool Heaters
    1. Electric Pool Heaters
    2. Other Issues
III. Public Participation

I. Authority and Background

    Title III, Part B \1\ of the Energy Policy and Conservation Act of 
1975 (``EPCA'' or ``the Act''), Public Law 94-163 (42 U.S.C. 6291-6309, 
as codified) sets forth a variety of provisions designed to improve 
energy efficiency and establishes the Energy Conservation Program for 
Consumer Products Other Than Automobiles.\2\ These include residential 
water heaters, direct heating equipment, and pool heaters (or 
collectively, ``heating products''), the subject of today's notice. (42 
U.S.C. 6292(a)(4),(9), and (11))
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    \1\ For editorial reasons, upon codification in the U.S. Code, 
Part B was redesignated as Part A.
    \2\ All references to EPCA in this document refer to the statute 
as amended through the Energy Independence and Security Act of 2007, 
Public Law 110-140 (Dec. 19, 2007).
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    Under EPCA, this program generally consists of four parts: (1) 
Testing; (2) labeling; (3) establishing Federal energy conservation 
standards; and (4) certification and enforcement procedures. The 
testing requirements consist of test procedures that

[[Page 63212]]

manufacturers of covered products must use as both the basis for 
certifying to DOE that their products comply with the applicable energy 
conservation standards adopted pursuant to EPCA, and for making 
representations about the efficiency of those products. (42 U.S.C. 
6293(c); 42 U.S.C. 6295(s)) Similarly, DOE must use these test 
requirements to determine whether the products comply with any 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 provides, in relevant part, that any test 
procedures prescribed or amended under this section must 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 must 
not be unduly burdensome to conduct. (42 U.S.C. 6293(b)(3))
    In addition, if DOE determines that a test procedure amendment is 
warranted, it must publish proposed test procedures and offer the 
public an opportunity to present oral and written comments on them. (42 
U.S.C. 6293(b)(2)) Finally, in any rulemaking to amend a test 
procedure, DOE must determine the extent to which the proposed test 
procedure would alter the product's measured energy efficiency. (42 
U.S.C. 6293(e)(1)) If DOE determines that the amended test procedure 
would significantly alter the measured efficiency of a covered product, 
DOE must amend the applicable energy conservation standard accordingly. 
(42 U.S.C. 6293(e)(2))
    Further, the Energy Independence and Security Act of 2007 (EISA 
2007) amended EPCA to require that at least once every 7 years, DOE 
must review test procedures for all covered products and either amend 
test procedures (if the Secretary determines that amended test 
procedures would more accurately or fully comply with the requirements 
of 42 U.S.C. 6293(b)(3)) or publish notice in the Federal Register of 
any determination not to amend a test procedure. (42 U.S.C. 
6293(b)(1)(A)) Under this requirement, DOE must review the test 
procedures for the various types of heating products not later than 
December 19, 2014 (i.e., 7 years after the enactment of EISA 2007). 
Thus, the final rule resulting from this rulemaking will satisfy the 
requirement to review the test procedures for heating products within 
seven years of the enactment of EPCA.
    DOE's test procedures for residential water heaters are found in 
the Code of Federal Regulations (CFR) at 10 CFR 430.23(e) and 10 CFR 
part 430, subpart B, appendix E. The test procedures include provisions 
for determining the energy efficiency (energy factor (EF)), as well as 
the annual energy consumption of these products.
    There are separate test procedures for the two types of direct 
heating equipment (i.e., vented home heating equipment and unvented 
home heating equipment), specifically 10 CFR 430.23(g) and 10 CFR part 
430, subpart B, appendix G for unvented home heating equipment, and 10 
CFR 430.23(o) and 10 CFR part 430, subpart B, appendix O for vented 
home heating equipment. (Hereafter in this notice, the terms ``vented 
heater'' and ``unvented heater'' are used as shorthand to describe the 
two types of direct heating equipment.) The vented heater test 
procedures include provisions for determining energy efficiency (annual 
fuel utilization efficiency (AFUE)), as well as annual energy 
consumption. The unvented heater test procedures currently have no 
provisions for determining energy efficiency, as all unvented heaters 
are considered 100-percent efficient. However, for unvented heaters 
that are the primary heating source for the home, there is a 
calculation of annual energy consumption based on a single assignment 
of active mode hours. For unvented heaters that are not the primary 
heating source for the home, there are no calculation provisions for 
either efficiency or annual energy consumption. Given that unvented 
heaters are considered 100-percent efficient, DOE has not established a 
test procedure for determining energy efficiency of these products (and 
thus, has not established energy conservation standards for these 
products), as there would be no energy savings that would result from 
such actions.
    DOE's test procedures for pool heaters are found at 10 CFR 
430.23(p) and 10 CFR part 430, subpart B, appendix P. The test 
procedures include provisions for determining two energy efficiency 
descriptors (i.e., thermal efficiency and pool heater heating seasonal 
efficiency), as well as seasonal energy consumption.
    In addition to the test procedure review provision discussed above, 
EISA 2007 also amended EPCA to require DOE to amend its test procedures 
for all covered products to include measurement of standby mode and off 
mode energy consumption. (42 U.S.C. 6295(gg)(2)(A)) Consequently, DOE 
is currently conducting a rulemaking to amend the test procedures for 
residential water heaters, direct heating equipment, and pool heaters 
to include provisions for measuring the standby mode and off mode 
energy consumption of those products. DOE published a NOPR in the 
Federal Register on August 30, 2010, which proposed updates to the DOE 
test procedures for heating products to address the standby mode and 
off mode test procedure requirements under EPCA.\3\ 75 FR 52892. DOE 
published a supplemental notice of proposed rulemaking (SNOPR) in the 
Federal Register on September 13, 2011, which calls for the use of the 
second edition of International Electrotechnical Commission (IEC) 
Standard 62301, ``Household Electrical Appliances--Measurement of 
standby power,'' in lieu of the first edition and also provides 
guidance on rounding and sampling. 76 FR 56347. However, that 
rulemaking was limited to the proposed test procedure updates to 
address the above-referenced standby mode and off mode requirements, 
and consequently, it did not address several other potential issues in 
DOE's existing test procedures for heating products. DOE plans to 
address these non-standby/off mode issues separately in this 
rulemaking. The potential issues that DOE has preliminarily identified 
and plans to address in this rulemaking are discussed in detail below 
in section II of this RFI.
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    \3\ For more information, please visit DOE's Web site at: http://www1.eere.energy.gov/buildings/appliance_standards/residential/waterheaters.html.
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II. Discussion

A. Test Procedure for Residential Water Heaters

1. Scope
    DOE's test procedures for water heaters codified at 10 CFR 
430.23(e) and 10 CFR part 430, subpart B, appendix E address gas-fired, 
electric, and oil-fired storage-type (i.e., storage volume not less 
than 20 gallons (76 L)) and gas-fired and electric instantaneous-type 
(i.e., storage volume less than 2 gallons (7.6 L)) water heaters. 
However, the procedure does not define electric instantaneous water 
heaters. In addition, it does not address the following types of 
products: (1) Gas-fired water heaters that have a storage volume at or 
above 2 gallons and less than 20 gallons (76 L); (2) electric storage 
water heaters with storage volume less than 20 gallons (76 L); and (3) 
storage water heaters with very large storage capacities, including 
oil-fired water heaters with storage volumes greater than 50 gallons 
(190 L), gas-fired water heaters with storage volumes above 100 gallons 
(379 L), and electric

[[Page 63213]]

water heaters with storage volumes above 120 gallons (454 L). For this 
rulemaking, DOE is considering an expansion of the scope of the test 
procedure to include definitions and test methods for these types of 
products.
a. Water Heaters With Storage Volumes Between 2 Gallons (7.6 L) and 20 
Gallons (76 L)
    DOE's current test procedures are not applicable to water heaters 
with storage tanks that are at or above 2 gallons (7.6 L) and less than 
20 gallons (76 L). In recent years, however, water heaters with such 
capacities have begun to populate the market. The definitions in the 
test procedure specify that instantaneous-type water heaters have a 
storage volume of less than two gallons (7.6 L) and that storage-type 
water heaters have a storage volume of 20 gallons (76 L) or more. 10 
CFR part 430, subpart B, appendix E, sections 1.7 and 1.12. The 
definition for ``Storage-type Water Heater of More than 2 Gallons (7.6 
Liters) and Less than 20 Gallons (76 Liters)'' is currently reserved. 
Id. at section 1.12.5. DOE is tentatively planning to address this gap 
in coverage by prescribing definitions and test procedures specifically 
for water heaters with storage volumes at or above 2 gallons (7.6 L) 
and less than 20 gallons (76 L). DOE seeks comment on the need for test 
procedures for products in this size range, as well as factors that 
should be considered when establishing a definition and test procedures 
for water heaters with storage volumes at or above 2 gallons (7.6 L) 
and 20 gallons (76 L). Additionally, DOE seeks comment on the need to 
characterize water heaters by attributes other than storage volume, 
such as heating or delivery capacity.
b. Electric Instantaneous Water Heaters
    DOE's current test procedures do not contain a definition for 
electric instantaneous water heaters, but rather have a space reserved 
to define them. 10 CFR part 430, subpart B, appendix E, section 1.7.1. 
However, EPCA defines electric instantaneous water heaters as having an 
input capacity of 12 kW or less, which impacts scope of coverage. (42 
U.S.C. 6291(27)(B)) Electric instantaneous water heaters are tankless 
water heaters (with storage volumes at or below 2 gallons (7.6 L)) that 
utilize electric heating elements to heat water on demand. The heating 
power required for electric instantaneous water heaters intended for 
whole home applications is typically much higher than the power 
capability commonly found in storage-type electric water heaters. Given 
the emergence of electric instantaneous water heaters on the market, 
DOE is tentatively planning to address this gap in the test procedure 
by prescribing a definition specifically for electric instantaneous 
water heaters. DOE seeks comment on the need for a definition for these 
products. Although DOE is bound by EPCA to limit its regulations to 
units with an input capacity of no more than 12kW, it also seeks 
comment on other factors to consider when establishing a definition for 
electric instantaneous water heaters.
    Additionally, DOE notes that the 24-hour simulated use test in 
DOE's test procedure for instantaneous water heaters at 10 CFR 430, 
Subpart B, Appendix E, section 5.2.4 is titled ``24-hour Simulated Use 
Test for Gas Instantaneous Water Heaters.'' However, upon reviewing the 
procedure in section 5.2.4 and the corresponding calculations in 
section 6 of the test procedure, DOE believes the test method is also 
applicable for electric instantaneous water heaters and is currently 
being used to determine the energy factor of those products. DOE plans 
to propose modifying section 5.2.4 to clarify the method for testing 
electric instantaneous water heaters and prevent confusion. DOE will 
also consider whether additional provisions may help clarify the test 
procedure as it applies to electric instantaneous water heaters. DOE 
seeks comments on the need to update its test procedure for determining 
the energy efficiency of electric instantaneous water heaters.
c. Storage Water Heaters With Very Large Storage Capacities
    The current DOE test procedure for residential water heaters only 
applies to gas-fired water heaters with storage volumes less than or 
equal to 100 gallons (379 L), electric storage water heaters with 
storage volumes less than or equal to 120 gallons (454 L), and oil-
fired water heaters with storage volumes less than or equal to 50 
gallons (190 L). 10 CFR part 430, subpart B, appendix E, sections 
1.12.1, 1.12.2, and 1.12.4. In defining storage type water heaters, 
EPCA covers residential gas-fired storage water heaters with an input 
of 75,000 Btu per hour or less, electric storage water heaters with an 
input of 12 kilowatts or less, and oil-fired storage water heaters that 
have an input rating of 105,000 Btu/h or less. (42 U.S.C. 6291(27)(A)) 
DOE is not aware of any residential water heaters available on the 
market with storage volumes above 100 gallons, 120 gallons, and 50 
gallons for gas-fired, electric, and oil-fired water heaters, 
respectively, that would be covered as residential products under EPCA. 
Due to the lack of water heaters with very large storage volumes that 
meet the definition of a residential water heater, DOE believes it is 
unnecessary to expand the scope of the test procedure to include gas-
fired products over 100 gallons, electric products over 120 gallons, or 
oil-fired products over 50 gallons, and seeks comment on this 
conclusion.
2. Draw Pattern
    The current residential water heater test procedure includes a 24-
hour simulated-use test for determining energy factor. 10 CFR part 430, 
subpart B, appendix E, sections 5.1.5 and 5.2.4. The 24-hour test 
specifies that 6 draws of equal volume be removed from the water heater 
in the first 6 hours of the test for a total draw of 64.3 gallons (243 
L). Following the six draws, the water heater sits in an idle mode for 
the duration of the 24-hour test. Id. The draw pattern is the same 
regardless of the characteristics (e.g., storage volume, input 
capacity) of the water heater.
    Recent data 4 5 6 suggest that the draw pattern can 
impact the energy factor of a water heater and can potentially offer an 
advantage to one type of water heater technology over another. In 
addition, these studies suggest that the existing draw pattern in the 
simulated use test may not be representative of actual draw patterns to 
which water heaters are subjected in the field. DOE recognizes that 
different water heaters will be subjected to different field demands 
(consumer usage patterns) because of their operational or performance 
differences. For example, it is a reasonable expectation that a small-
volume storage water heater (e.g., 30 gallons) designed for low-
occupancy dwellings would not have to meet or be subjected to the same 
hot water demand or usage pattern that a large-volume water heater 
(e.g., 75 gallon) is designed to accommodate. Given this understanding, 
if DOE continues to use a simulated use test (DOE is also considering a 
series of discrete tests to replace the simulated use test; see section 
II.A.3 below), DOE will consider revising the draw pattern to be more 
representative of typical usage patterns

[[Page 63214]]

experienced in the field. DOE may also consider amendments to its test 
procedure to provide for different draw patterns for different water 
heaters based upon the characteristics of each water heater, such as 
the amount of hot water the unit can provide, the storage volume, or 
the heating rate (i.e., input rate). DOE seeks comments on possible 
improvements that could be made to DOE's existing 24-hour simulated use 
test procedure for water heaters. In particular, DOE seeks comments on 
typical residential hot water usage patterns (e.g., the number of draws 
during a day's use, the timing of and spacing between those draws, the 
lengths of the draws, the flow rates at which those draws are taken) 
and considerations for establishing different draw patterns based on 
differing water heater characteristics.
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    \4\ Healy, WM, Ullah, T, and Roller, J., ``Input-Output Approach 
to Predicting the Energy Efficiency of Residential Water Heaters--
Testing of Gas Tankless and Electric Storage Water Heaters,'' ASHRAE 
Transactions 117 (2011).
    \5\ Hoeschele, M.A. and Springer, D.A. ``Field and Laboratory 
Testing of Gas Tankless Water Heater Performance,'' ASHRAE 
Transactions 114 (2): 453-461 (2008).
    \6\ Bohac, D, Schoenbauer, B., Hewett, M., Lobenstein, M.S., 
Butcher, T. ``Actual Savings and Performance of Natural Gas Tankless 
Water Heaters,''. Center for Energy and Environment Report for 
Minnesota Office of Energy Security (August 30, 2010).
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3. Discrete Performance Tests
    As noted above, DOE is considering a series of discrete tests as an 
alternative approach to using a 24-hour simulated use test in 
determining energy factor for residential water heaters. The results of 
the discrete tests would be used as inputs into an algorithm to 
calculate the energy factor. The discrete tests would determine factors 
such as thermal efficiency (or coefficient of performance (COP)), 
recovery efficiency, standby energy loss coefficient, and cycling 
losses. The results of these tests, and possibly other tests, could 
then be mathematically combined to calculate an energy factor rating.
    DOE believes that using the mathematically-combined results of 
discrete tests to calculate energy factor offers several benefits, but 
it also has some drawbacks when compared to using a 24-hour simulated 
use test. Discrete tests may lead to simpler, more repeatable tests, 
and DOE tentatively believes the results of discrete tests could 
potentially be used as inputs to simulation models for predicting 
energy consumption and that an array of different installations and 
field conditions could be modeled. However, DOE is uncertain of the 
feasibility of characterizing water heaters and developing an energy 
factor algorithm based on empirical data because it is not aware of any 
such algorithms that have been thoroughly proven to be effective at 
estimating the energy factor. Another challenge would be that the tests 
may need to vary for different technologies, thereby raising possible 
concerns about test equitability. DOE also notes that a simulated use 
test has the advantage of placing the same demand on any water heater 
suitable for a particular application, thereby arguably leading to a 
more equitable test. DOE seeks comments on the benefits and drawbacks 
of using a series of discrete performance tests in place of the current 
24-hour simulated use test for determining the energy factor of 
residential water heaters. DOE also requests comments on the 
feasibility and equitability of a series of discrete tests and possible 
approaches for establishing discrete tests that can result in an energy 
factor rating.
4. Test Conditions
a. Water Delivery Temperature
    The current residential water heater test procedure calls for hot 
water to be delivered at 135 [deg]F +/- 5 [deg]F (57.2 [deg]C +/- 2.8 
[deg]C). 10 CFR part 430, subpart B, appendix E, section 2.4. However, 
the Underwriters Laboratories (UL) standards specify that manufacturers 
must ship residential water heaters with thermostats set at 
temperatures no greater than 125 [deg]F (52 [deg]C) to safeguard 
against scalding hazards. (UL 174, Standard for Household Electrical 
Storage Tank Water Heaters, Underwriters Laboratories (April 29, 2004)) 
DOE's research suggests that the majority of water heaters are shipped 
with the thermostat preset to 120 [deg]F (49 [deg]C). In the analysis 
for the April 2010 final rule amending energy conservation standards 
for water heaters, the Department estimated that the average set point 
temperature for a residential water heater was 124.2 [deg]F (51.2 
[deg]C), with an estimated 61 percent of water heaters being installed 
with a set point at 120 [deg]F (49 [deg]C). (For more information see 
chapter 7 of the technical support document (TSD) for DOE's April 16, 
2010 final rule (75 FR 20112) for energy conservation standards for 
residential heating products.\7\)
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    \7\ Docket number EE-2006-BT-STD-0129. The TSD is available 
online at: http://www.eere.energy.gov/buildings/appliance_standards/residential/heating_products_fr_tsd.html.
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    The set point impacts the performance of various types of water 
heaters differently, and as a result, DOE plans to reexamine the 
appropriateness of the set point specifications in the test procedure. 
A higher delivery temperature has a disproportionately large and 
negative impact on heat pump water heater efficiency, because heat pump 
water heaters can have markedly different performance at elevated 
stored water temperature compared to temperatures more representative 
of typical residential usage. For other types of water heaters, heat 
transfer characteristics between the heating source and the water may 
differ at lower delivery temperatures, thereby affecting efficiency.
    DOE notes that some end uses (e.g., dishwasher operation) require 
hot water delivered at 130 [deg]F to 140 [deg]F (54 [deg]C to 60 
[deg]C) for effective operation. While most of these machines contain 
booster heaters that can increase the water temperature, there are some 
machines not so equipped that require the water heater to be set to a 
higher temperature in order to operate properly. Additionally, concerns 
exist about the potential for the growth of Legionella in hot water 
stored below 135 [deg]F (57 [deg]C). ASHRAE Guideline 12, ``Minimizing 
the Risk of Legionellosis Associated with Building Water Systems,'' \8\ 
states that the temperature range most favorable for amplification of 
legionellae bacteria is 77-108 [deg]F (25-42 [deg]C), and that document 
recommends that when practical, hot water should be stored at 
temperatures of 120 [deg]F (49 [deg]C) or above. However, the guideline 
also states that for high-risk situations (such as in health care 
facilities and nursing homes), hot water should be stored above 140 
[deg]F (60 [deg]C).
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    \8\ For more information visit: http://www.ashrae.org.
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    DOE believes the test procedure for residential water heaters 
should be representative of the conditions typically encountered in the 
field. DOE also recognizes that not all water heaters in the field will 
be set at 135 [deg]F (57 [deg]C), because the majority of water heaters 
are shipped pre-set at 120 [deg]F (49 [deg]C), and DOE does not believe 
most consumers change their water heaters' set points. DOE seeks 
comment on the appropriate set point temperature for the residential 
water heater test procedure.
b. Ambient Temperature and Relative Humidity
    The residential water heater test procedure generally requires that 
testing be performed in an environment fixed at 67.5 [deg]F +/- 2.5 
[deg]F (19.7 [deg]C +/- 1.4 [deg]C). For heat pump water heaters, 
however, the environmental conditions are more tightly constrained at 
67.5 [deg]F +/- 1 [deg]F (19.7 [deg]C +/- 0.6 [deg]C) and 50 percent +/
- 1 percent relative humidity, because the heat pump water heater 
energy use is highly dependent on the ambient temperature and relative 
humidity. Because water heaters are placed in a wide variety of 
locations within and outside of a home, and given the large impact of 
these factors on heat pump water heater efficiency, DOE plans to 
reexamine the ambient air test conditions specified in the test 
procedure in order to assess whether the currently-specified conditions 
are

[[Page 63215]]

representative of those conditions that are typically encountered in 
residential installations. Therefore, to help assess the ambient 
temperature and relative humidity requirements in the residential water 
heater test procedure for this rulemaking, DOE seeks comment on the 
appropriate ambient temperature and relative humidity testing points 
and tolerances for all types of residential water heaters.
5. Other Issues
    DOE also seeks comments on other relevant issues that would affect 
the test procedures for residential water heaters. Although DOE has 
attempted to identify those portions of the test procedure where it 
believes amendments may be warranted, interested parties are welcome to 
provide comments on any aspect of the test procedure, including updates 
of referenced standards, as part of this comprehensive 7-year-review 
rulemaking.

B. Test Procedure for Direct Heating Equipment

1. Vented Hearth Heaters
    The vented home heating equipment test procedures are codified at 
10 CFR 430.23(o) and 10 CFR part 430, subpart B, appendix O. Appendix O 
provides for a complete evaluation of the efficiency of vented direct 
heating equipment in order to determine the product's AFUE, which is 
the regulating metric set by EPCA. (42 U.S.C. 6291(22)(A)) In the April 
2010 final rule adopting energy conservation standards for heating 
products, DOE established a separate product class of vented home 
heating equipment for vented hearth heaters, and determined that DOE's 
test procedures in Appendix O would apply to vented hearth products.
    DOE is interested in whether the test procedure for vented home 
heating equipment is being applied uniformly for vented hearth heaters. 
This would apply to both the actual testing provisions and the 
application of the equations to determine annual efficiency (i.e., 
AFUE) and annual energy consumption. DOE currently believes that vented 
hearth heater manufacturers can use the existing test procedure 
provisions for manually-controlled vented heaters to produce uniform 
and representative measures of energy consumption and efficiency. 
However, DOE also believes that technical clarifications or other 
improvements designed to avoid non-uniform application should always be 
considered. To this end, DOE seeks information on any clarification, 
updates, or technical improvements that would allow for uniform and 
representative measures of energy consumption and efficiency across all 
vented hearth heaters.
2. Other Issues
    DOE also seeks comments on other relevant issues that would affect 
the test procedures for residential direct heating equipment (both 
vented type and unvented type). Although DOE has attempted to identify 
those portions of the test procedure where it believes amendments may 
be warranted, interested parties are welcome to provide comments on any 
aspect of the test procedure, including updates of referenced 
standards, as part of this comprehensive 7-year-review rulemaking.

C. Test Procedure for Pool Heaters

1. Electric Pool Heaters
    DOE's test procedures for pool heaters are found at 10 CFR 
430.23(p) and 10 CFR part 430, subpart B, appendix P. In its definition 
of ``efficiency descriptor,'' EPCA specifies that for pool heaters, the 
efficiency descriptor shall be ``thermal efficiency.'' (42 U.S.C. 
6291(22)(E)) Further, EPCA defines the ``thermal efficiency of pool 
heaters'' as the ``measure of the heat in the water delivered at the 
heater outlet divided by the heat input of the pool heater as measured 
under test conditions specified in section 2.8.1 of the American 
National Standard for Gas Fired Pool Heaters, Z21.56-1986, or as may be 
prescribed by the Secretary.'' (42 U.S.C. 6291(26)) \9\ As part of a 
recent test procedure rulemaking, DOE proposed a new efficiency metric 
for pool heaters, titled ``integrated thermal efficiency.'' 75 FR 
52892, 52899-901 (August 30, 2010).\10\ The proposed integrated thermal 
efficiency metric builds on the existing thermal efficiency metric and 
includes the additional electrical energy consumption during standby 
mode and off mode operation, as required by EISA 2007. (42 U.S.C. 
6295(gg)(2)(A)) DOE notes that because current energy conservation 
standards for pool heaters do not account for standby mode and off mode 
energy use, manufacturers are not required to certify compliance using 
the integrated thermal efficiency metric at this time. Until such time 
as compliance is required with amended energy conservation standards 
that do account for standby mode and off mode energy consumption, 
manufacturers are to continue using the thermal efficiency metric for 
certification and compliance purposes.
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    \9\ In an August 2010 NOPR, DOE proposed to use the most recent 
version of this standard, ANZI Z21.56-2006. 75 FR 52892, 52899-901 
(August 30, 2010).
    \10\ DOE subsequently published an SNOPR for this rulemaking on 
September 13, 2011. 76 FR 56347. However, this SNOPR did not modify 
the proposal for integrated thermal efficiency contained in the 
August 2010 NOPR.
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    Certain types of pool heaters are powered by energy sources other 
than gas, and DOE believes that absent modifications, the currently 
incorporated ANSI Z21.56 test method for gas-fired pool heaters may not 
be appropriate for pool heaters that operate with electricity 
(including heat pump pool heaters) or oil. However, DOE notes that its 
test procedure for pool heaters at 10 CFR 430 Subpart B, Appendix P 
already contains slight modifications to allow the ANSI Z21.56 test 
method to be applied to oil-fired pool heaters, and DOE does not 
believe further action is necessary for those products. In the December 
2009 NOPR for energy conservation standards for heating products DOE 
determined that as currently drafted, the DOE test procedure for pool 
heaters is not suitable for electric pool heaters (including heat pump 
pool heaters), largely based upon the fact that EPCA specifies that 
``thermal efficiency'' must be the efficiency descriptor for these 
products. DOE sought comment regarding potential ways to apply a 
thermal efficiency metric to electric pool heaters (including heat pump 
pool heaters). 74 FR 65852, 65866-67 (Dec. 11, 2009).
    For electric pool heaters (including those units using heat pump 
technology), the relevant energy input is electricity instead of gas. 
``Thermal efficiency,'' as determined using ANSI Z21.56, is a measure 
of heat in the water delivered at the heater outlet (in Btu/h) divided 
by the heat input (in Btu/h) of the fuel. It is possible to develop an 
integrated thermal efficiency rating for a heat pump pool heater by 
converting the power input in watts to the input in Btu/h. However, if 
such an integrated thermal efficiency metric were applied to heat pump 
pool heaters, DOE notes that the numerical result would be efficiency 
ratings of over 100 percent, which may cause confusion for consumers 
because heat pumps are typically rated using industry standards for 
Coefficient of Performance (COP). In contrast, electric pool heaters 
that operate with resistance heating (as opposed to heat pump 
technology), are typically rated with a thermal efficiency metric. 
Consequently, the ratings for electric pool heaters using these two 
competing technologies are not always directly comparable. Another 
consideration for heat pump pool heaters is that performance depends

[[Page 63216]]

upon the ambient temperature and humidity, so environmental conditions 
for testing are much more important for heat pump pool heaters than for 
gas-fired pool heaters.
    In light of the above, DOE tentatively plans to update the pool 
heater test procedures by adding provisions to address electric heat 
pump pool heaters through use of a COP performance metric drawn from 
industry standards, coupled with a separate conversion to thermal 
efficiency (i.e., the regulating metric specified in EPCA) and 
integrated thermal efficiency (i.e., the new regulating metric, as 
amended by EISA 2007). Because there are currently no energy 
conservation standards for electric heat pump pool heaters, no 
certification or reporting would be required for those products until 
such time as DOE sets minimum energy conservation standards for those 
products (which will include energy consumption in active, standby, and 
off modes). However, after a test method is adopted for electric heat 
pump pool heaters, manufacturers would be required to use the DOE test 
method for making efficiency representations and would be able to use 
the COP metric, the integrated thermal efficiency metric, or both for 
making efficiency representations during this interim period. 
Compliance with the amended test procedure for representations purposes 
would be required 180 days after the date of publication of the test 
procedure final rule. Once DOE sets energy conservation standards for 
pool heaters, EPCA requires the use of the thermal efficiency metric. 
Therefore, if DOE were to set energy conservation standards for heat 
pump pool heaters, manufacturers would then be required to rate their 
products using the integrated thermal efficiency metric, although they 
would still have the option of making supplemental representations of 
efficiency using the COP metric.
    DOE requests comment on the applicability of the ANSI Z21.56 test 
method for pool heaters that are powered by energy sources other than 
gas. Additionally, DOE seeks comment on its tentative plans for 
updating the pool heater test procedure to include electric pool 
heaters and information on potential methods to apply the integrated 
thermal efficiency metric to electric pool heaters (including heat pump 
pool heaters).
2. Other Issues
    DOE also seeks comments on other relevant issues that would affect 
the test procedures for residential pool heaters. Although DOE has 
attempted to identify those portions of the test procedure where it 
believes amendments may be warranted, interested parties are welcome to 
provide comments on any aspect of the test procedure as part of this 
comprehensive 7-year-review rulemaking.

III. Public Participation

    DOE invites all interested parties to submit in writing by November 
28, 2011, comments and information on matters addressed in this notice 
and on other matters relevant to DOE's consideration of amended test 
procedures for residential water heaters, direct heating equipment, and 
pool heaters.
    After the close of the comment period, DOE will begin collecting 
data, conducting relevant analyses, and reviewing the public comments. 
These actions will be taken to aid in the development of a test 
procedure NOPR for residential water heaters, direct heating equipment, 
and pool heaters.
    DOE considers public participation to be a very important part of 
the process for developing test procedures. DOE actively encourages the 
participation and interaction of the public during the comment period 
in each stage of the rulemaking process. Interactions with and between 
members of the public provide a balanced discussion of the issues and 
assist DOE in the rulemaking process. Anyone who wishes to be added to 
the DOE mailing list to receive future notices and information about 
this rulemaking should contact Ms. Brenda Edwards at (202) 586-2945, or 
via e-mail at [email protected].

    Issued in Washington, DC, on September 29, 2011.
Kathleen Hogan,
Deputy Assistant Secretary for Energy Efficiency, Office of Technology 
Development, Energy Efficiency and Renewable Energy.
[FR Doc. 2011-25815 Filed 10-11-11; 8:45 am]
BILLING CODE 6450-01-P