This document, concerning Energy Conservation Program for Consumer Products: Test 

Procedure for Residential Furnaces and Boilers, is a rulemaking action issued by the Department 

of Energy. Though it is not intended or expected, should any discrepancy occur between the 

document posted here and the document published in the Federal Register, the Federal Register 

publication controls. This document is being made available through the Internet solely as a 

means to facilitate the public's access to this document. 

Scheduled publication: January 4, 2013 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[6450-01-P] 

DEPARTMENT OF ENERGY 

10 CFR Part 430 

[Docket Number EERE–2012–BT–TP–0024] 

RIN: 1904-AC79 

Energy Conservation Program for Consumer Products: Test Procedure for Residential 

Furnaces and Boilers 

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

ACTION: Request for information (RFI). 

SUMMARY: The U.S. Department of Energy (DOE) is initiating a rulemaking and data 

collection process to consider amendments to DOE's test procedure for residential furnaces and 

boilers. Because DOE has recently completed a test procedure rulemaking for the standby mode 

and off mode energy consumption of these products, the primary focus of this rulemaking will be 

on active mode operation. 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 currently applicable test procedures, including 

topics on which DOE is particularly interested in receiving comment. In overview, the issues 

outlined in this document mainly concern reducing the test burden, test conditions impacting the 

1 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

annual fuel utilization efficiency (AFUE) metric, test conditions impacting non-AFUE efficiency 

parameters, the performance test for automatic means in boilers, harmonization of standards, 

alternative methods for furnace/boiler efficiency determination, and scope. These topics (and 

others which commenters identify) are ones which DOE anticipates may lead to proposed test 

procedure amendments 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 

furnaces and boilers, including topics not specifically raised in this RFI. 

DATES: Written comments and information are requested on or before February 19, 2013. 

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-0024 and/or RIN 1904-AC79, by any of the following methods: 

E-mail: Res-Furnaces-Boilers-2012-TP-0024@ee.doe.gov. Include EERE–2012–BT–

TP-0024 and/or RIN 1904-AC79 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. 

2 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Hand Delivery/Courier: Ms. Brenda Edwards, U.S. Department of Energy, Building 

Technologies Program, 6th Floor, 950 L’Enfant Plaza, SW., 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. 

Instructions: All submissions received must include the agency name and docket number 

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, EE–2J, 1000 Independence Avenue, SW., 

Washington, DC 20585–0121. Telephone: (202) 586–7892. E-mail: 

residential_furnaces_and_boilers@ee.doe.gov . 

Mr. Eric Stas, U.S. Department of Energy, Office of the General Counsel, GC-71, 1000 

Independence Avenue, SW., Washington, DC 20585-0121. Telephone: (202) 586-9507. Email: 

Eric.Stas@hq.doe.gov. 

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, 

3 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Building Technologies Program, EE-2J, 1000 Independence Avenue, SW., Washington, DC 

20585-0121. Telephone: (202) 586-2945. E-mail: Brenda.Edwards@ee.doe.gov. 

SUPPLEMENTARY INFORMATION: 

Table of Contents 

I. Authority and Background 

II. Discussion 

A. Reducing Test Burden 

B. Test Conditions Impacting Energy Efficiency (AFUE) Performance 

C. Test Conditions Impacting Non-AFUE Efficiency Parameters 

D. Performance Test for Automatic Means in Boilers 

E. Harmonization of Standards 

F. Alternative Methods for Furnace/Boiler Efficiency Determination 

G. Scope 

H. Standby Mode and Off Mode 

I. 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 including residential furnaces and boilers. (42 

U.S.C. 6291(1)–(2) and 6292(a)(5)) 

1 This part was originally titled Part B. It was redesignated Part A in the United States Code for editorial reasons. 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). 

4 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Under the Act, this program consists essentially 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 manufacturers of covered 

products must use as both the basis for certifying to DOE that their products comply with 

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 procedures to determine whether the products comply with 

any relevant standards adopted under EPCA. (42 U.S.C. 6295(s)) 

Under 42 U.S.C. 6293, EPCA sets forth criteria and procedures that 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 alter the measured efficiency of a covered product, DOE must 

amend the applicable energy conservation standard accordingly. (42 U.S.C. 6293(e)(2)) 

5 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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 the 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 residential furnace and boiler 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 

furnaces and boilers within seven years of the enactment of EPCA. 

DOE’s test procedure for residential furnaces and boilers is found at 10 CFR 430.23(n) 

and 10 CFR part 430, subpart B, appendix N, Uniform Test Method for Measuring the Energy 

Consumption of Furnaces and Boilers. DOE established its test procedures for furnaces and 

boilers in a final rule published in the Federal Register on May 12, 1997. 62 FR 26140. This 

procedure establishes a means for determining annual energy efficiency (AFUE) and annual 

energy consumption of gas-fired, oil-fired, and electric furnaces and boilers. 

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 amended its test procedures for residential furnaces and boilers to include 

6 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

provisions for measuring the standby mode and off mode energy consumption of those products. 

DOE published a final rule in the Federal Register on October 20, 2010, which updated the DOE 

test procedures for residential furnaces and boilers to address the standby mode and off mode test 

procedure requirements under EPCA. 75 FR 64621. Since that time, DOE published a notice of 

proposed rulemaking (NOPR) 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 

incorporated by reference in the earlier final rule, as well as providing guidance on rounding and 

sampling. 76 FR 56339. On December 31, 2012, DOE published in the Federal Register its 

second test procedure final rule for furnaces and boilers related to standby mode and off mode, 

which incorporated by reference IEC Standards 62301 (Second Edition) and provided related 

rounding and sampling guidance. However, that rulemaking was limited to test procedure 

updates to address the above-referenced standby mode and off mode requirements, and 

consequently, it has not considered several other potential non-standby mode/off mode issues in 

DOE's existing test procedures for residential furnaces and boilers which DOE plans to address 

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. 

In support of its test procedure rulemaking, DOE conducts in-depth technical analyses of 

publicly-available test standards and other relevant information. DOE continually seeks data and 

public input to improve its testing methodologies to more accurately reflect consumer use and to 

produce repeatable results. In general, DOE is requesting comment and supporting data 

regarding representative and repeatable methods for measuring the energy use of residential 

7 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

furnaces and boilers. Additionally, DOE seeks comment and information on the specific topics 

below. 

II. Discussion 

A. Reducing Test Burden 

DOE plans to identify available opportunities to potentially reduce testing burden by 

simplifying appropriate parts of the residential furnaces and boilers test procedure. Knowledge 

of a unit's physical characteristics may make it possible to reliably predict certain performance 

parameters without conducting testing. If so, replacing certain burdensome tests with default 

factors could significantly reduce the testing burden (time to conduct a test or cost of testing) 

without sacrificing the validity of the test results. Of course, manufacturers would retain the 

option to conduct actual testing, rather than rely on default values. 

DOE plans to also reassess existing default factors in the test procedure, many of which 

were created years ago and might no longer be relevant for some of today’s product designs. For 

example, the existing off-cycle draft factor for flue gas flow (DF) default value of 0.4 for induced 

draft products was established for clamshell heat exchangers intended for use in gravity vented 

units. Today’s products are designed with more restrictive heat exchangers (tubes and small 

formed sections) and are likely to result in draft factors less than 0.4. Regarding default factors, 

DOE requests input and comments on: 

(1)	 Defining default draft factors3 for each product with different physical 

characteristics; 

3 Identified default draft factors in DOE’s residential furnaces and boilers test procedure include the off-cycle draft 

factor for flue gas flow (DF), the off-cycle draft factor for stack gas flow (DS), the off-cycle draft factor for stack gas 

8 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(2)	 Defining default jacket loss4 factors for each product type; 

(3)	 The appropriateness of replacing the “heat up” and “cool down” tests with default 

seasonal factors to account for the year-round performance of the equipment. If so, 

should these factors be based on physical characteristics of the equipment being 

evaluated, and should the use of default factors be optional or mandatory? Also, 

DOE is requesting data about the effect of the heat up and cool down test result 

measurements on AFUE calculation, the range and repeatability of the test results, 

and the degree to which such results are correlated with physical attributes of the 

tested product. 

(4)	 Simplifying the calculation procedure for determining the burner cycling and draft 

losses used to compute seasonal efficiency without losing important insight about a 

product’s relative energy performance; and

(5)	 Other default values that need updating or parameters currently measured that could 

be replaced with default values. 

B. Test Conditions Impacting Energy Efficiency (AFUE) Performance 

DOE is interested in receiving comments about improving the test procedure’s 

effectiveness in quantifying energy efficiency performance under typical field conditions. DOE 

has identified opportunities to reduce variability, eliminate ambiguity, and address discrepancies 

between the test procedure and actual field conditions. On this topic, DOE seeks input on the 

following issues: 

flow without a stack damper (DS

O), and the power burner draft factor (DP). DF is the ratio of gas mass flow rate 

through the flue during the off-cycle to the gas mass flow rate through the flue during the on-cycle at identical 

temperatures. DP is the ratio of the rate of flue gas mass flow through the furnace during the off-period to the rate of 

flue gas mass flow through the furnace during the on-period. 

4 Identified default jacket loss factors in DOE’s residential furnaces and boilers test procedure include jacket loss

factor (CJ) and jacket loss (LJ), which measure the losses resulting from heat escaping the furnace or boiler jacket. 

9 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(1)	 The DOE test procedure incorporates by reference the American Society of 

Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 103-

1993.5 In 2007, ASHRAE published a revised version of Standard 103 (ASHRAE 

Standard 103-2007), which was updated to reflect improvements and changes in 

equipment design that were not adequately covered by the previous version of the 

standard. In particular, attention was given to the modern classes of two-stage and 

modulating equipment that have come on the market, as well as equipment whose 

performance is affected by post purge of the combustion chamber. Greater 

understanding and clarity regarding energy losses were also incorporated into the 

updated ASHRAE standard. Finally, changes in nomenclature and definitions were 

included to clarify meaning within the standard, a need reflected by questions and 

issues posed to ASHRAE committee members over the past 10 years. Furthermore, 

editorially, the errata from the previous version were incorporated into this version. 

DOE plans on updating its references to the current ASHRAE Standard 103-20076 

and seeks comments on which sections of ASHRAE 103-2007 should be included 

in the DOE test procedure. 

(2)	 DOE plans to review the tolerance ranges for measuring important variables such as 

fuel calorific value, weight of condensate, water flow and temperature, voltage, and 

flue gas composition. DOE seeks comment as to whether the existing tolerance 

5 American Society of Heating Refrigerating and Air-Conditioning Engineers Inc., ASHRAE Standard: Method of 

Testing for Annual Fuel Utilization Efficiency of Residential Central Furnaces and Boilers (1993) Report No. 

ANSI/ASHRAE 103-1993. 6 American Society of Heating Refrigerating and Air-Conditioning Engineers Inc., ASHRAE Standard: Method of 

Testing for Annual Fuel Utilization Efficiency of Residential Central Furnaces and Boilers (2007) Report No. 

ANSI/ASHRAE 103-2007. 

10 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ranges for measuring variables in the test procedure are acceptable or whether DOE 

should define different methods of measuring and recording such variables. 

(3)	 DOE plans to review the statistical variability encountered during testing in 

important variables such as firing rate, heating media temperatures and flow rates, 

and ambient air temperature. For example, the firing rate is generally to be set and 

held to within ±2% of the nameplate rating. DOE seeks comment regarding 

whether this range should be narrowed. 

(4)	 Room ambient air temperatures are currently allowed to vary widely. Under the 

DOE test procedure, the room temperature is allowed to be between 65°F and 

100°F, except for condensing furnaces and boilers, where the room temperature 

shall not exceed 85°F. DOE plans to review whether it is appropriate to tighten the 

allowable room air temperature range. DOE seeks comment as to whether it should 

tighten the allowable room air temperature range. 

(5)	 Currently, a minimum draft factor of 0.05 can be applied to products with restricted 

flueways without providing a list of qualifications or instructions as to how to 

verify that the units are designed with no measurable airflow through the 

combustion chamber and heat exchanger during the burner off-period. DOE seeks 

comment as to whether and under what conditions, a minimum draft factor should 

be used for products with restricted flueways and how the conditions could be 

verified if questions arose. 

(6)	 DOE requires all non-weatherized boilers to be rated as indoor equipment (see 10 

CFR part 430, subpart B, appendix N, section 10.1). This implies that direct vent 

boilers that would normally meet the definition of System 9 or System 10 should 

11 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

instead be defined as one of the other System numbers.7 DOE plans to review 

whether it is appropriate for direct vent boilers to be calculated according to System 

3 or alternatively according to System 9 or 10, but with jacket losses excluded (i.e., 

LJ=0). DOE seeks input regarding how direct vent boilers should be tested. 

(7)	 DOE plans to review the current value of the oversize factor8 (0.7) to investigate 

whether current field installations can be better approximated, for both furnaces and 

boilers. DOE seeks comment regarding an appropriate value for the oversize factor. 

(8)	 Currently, the DOE test procedure provides that water supply temperature must be 

between 120°F and 124°F for non-condensing hot water boilers and 120°F (±2°F) 

for condensing hot water boilers. DOE plans to review the value for the water 

supply temperature for non-condensing and condensing boilers. DOE seeks 

comment on the appropriate water supply temperature for measuring the 

performance of non-condensing and condensing boilers. Should DOE change the 

water temperatures for condensing boilers to reflect the lower temperatures 

encountered in low-temperature radiant installations? 

(9)	 The current DOE test procedure does not specify that the tested equipment is set up 

according to recommended field settings as defined in the product's installation and 

operation manual. This potentially allows the unit to be tested under conditions that 

are different from the field or may not be recommended for safety reasons. 

7 System numbers are used in the ASHRAE 103 test procedure to categorize the different types of furnaces and 

boilers to be tested. “System 9” or “System10” refer to furnaces or boilers that are outdoor, direct vent, or isolated 

combustion systems. “System 3” refers to furnaces or boilers that can use indoor combustion air and have direct 

exhaust. 

8 “Oversize factor” accounts for the national average oversizing of equipment that occurs when a heating equipment

is sized to satisfy more than the heating load of the household. This is typically done to size the equipment so that it 

is able to satisfy the days in which the house heating requirements might be exceeded and/or to take into account 

uncertainties regarding house heating load. For example, a 0.7 oversize factor is equivalent to 30-percent oversizing 

of the heating equipment (in other words, 30 percent greater input capacity than is required). 

12 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Examples of such test conditions include a different flue CO2 percentage or reduced 

input rate from the recommended field settings. DOE plans to review the use of 

manufacturer-recommended values in testing, such as the minimum firing rate for 

testing a unit equipped with manually-adjustable controls (see ASHRAE 103-2007, 

section 8.4.1.1.2) and target flue gas CO2 levels. Should DOE change the test 

procedure to specify that the tested equipment is set up according to recommended 

field settings as defined in the product's installation and operation manual? 

(10)	 AFUE ratings are typically reported in manufacturer product literature and on 

directories of certified products to the nearest 0.1, but this is neither specified in the 

DOE test procedure nor explicitly required by the Federal Trade Commission 

(FTC). Instead, DOE’s test procedure specifies that the AFUE rating should be 

rounded to the nearest whole percentage point (see 10 CFR 430.23(n)(2)). DOE 

plans to specify the requisite number of significant digits as part of this test 

procedure rulemaking. DOE solicits input on how much precision is statistically 

possible. 

(11)	 Vent stack requirements differ between ANSI Z21.139 or ANSI Z21.4710 and the 

DOE test procedure. DOE plans to review the difference in efficiency rating 

attributable to the differences in vent stack configuration between the DOE test 

procedure and ANSI Z21.13 or ANSI Z21.47. DOE seeks comment on whether it 

should consider adopting the same vent stack requirements as set forth in ANSI 

Z21.13 or ANSI Z21.47. 

9 American National Standards Institute, American National Standard/CSA Standard for Gas-Fired Low Pressure 

Steam and Hot Water Boilers (2010) Report No. ANSI Z21.13-2010, CSA 4.9-2010. 10 American National Standards Institute, American National Standard/CSA Standard for Gas-Fired Central 

Furnaces (2006) Report No. ANSI Z21.47-2006, CSA 2.3-2006. 

13 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C. Test Conditions Impacting Non-AFUE Efficiency Parameters 

DOE plans to improve the ability of the test procedure to measure non-AFUE energy 

efficiency parameters under typical field conditions. Regarding this topic, DOE seeks input on: 

(1)	 The boiler test procedure measures only the power supplied to the power burner 

motor, the ignition device, and the circulating pump (see 10 CFR part 430, subpart 

B, appendix N, section 10.2.1). Some boilers are equipped with an internal pump 

used to maintain a minimum flow rate through the heat exchanger that does not 

function as a system circulating pump. DOE seeks comment on whether the boiler 

average annual auxiliary electrical energy consumption (EAE) calculations should 

include one system circulating pump and an additional pump (if present) that 

circulates water during the operation of the burner. 

(2)	 Modulating power burners are often equipped with variable speed motors. The 

efficiency of the motor/blower combination changes with the firing rate. The same 

may be true for circulating pumps. Currently, DOE’s test procedure assumes a 

fixed motor efficiency. For equipment with modulating power burners, using a 

fixed motor efficiency would produce inaccurate electricity consumption estimates, 

since the motor efficiency varies at the different firing rates. DOE plans to 

incorporate a method for part-load efficiency into its electricity consumption 

calculations for modulating equipment. DOE requests input regarding the 

appropriateness of incorporating a method for part-load efficiency into its electricity 

consumption calculations and input on what method DOE should use. 

14 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(3)	 The current DOE test procedure includes power consumed by the ignition device, 

circulating pump, and power burner motors, but it ignores other devices that use 

power during the active mode (e.g., gas valve and safety and operating controls). 

DOE plans to consider including any electrical power consumption not already 

measured during the active mode. DOE seeks comment regarding how to address 

any electrical power consumption not already measured during the active mode. 

(4)	 Historical energy use data show that national average house heating loads have 

been changing because of increased household square footage, improved building 

shell efficiency, changes in the distribution of where this equipment is installed, and 

changes in average weather conditions. DOE plans to review the parameters to 

calculate the burner operating hours in section 10.2.1 of the DOE test procedure 

(i.e., national average heating load hours and the adjustment factor). DOE seeks 

comment regarding what national average values should be used to calculate burner 

operating hours. 

D. Performance Test for Automatic Means in Boilers 

In 2008, DOE published a technical amendment to the 2007 furnace and boiler final rule 

(72 FR 65136 (Nov. 19, 2007)) to add a number of design requirements set forth in EISA 2007. 

73 FR 43611 (July 28, 2008). These requirements prohibit constant-burning pilot lights for gasfired hot water boilers and gas-fired steam boilers, and require an automatic means for adjusting 

the water temperature for gas-fired hot water boilers, oil-fired hot water boilers, and electric hot 

water boilers. The automatic means for adjusting water temperature must automatically adjust 

the temperature of the water supplied by the boiler to ensure that an incremental change in 

15 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

inferred heat load produces a corresponding incremental change in the temperature of water 

supplied. 

While these requirements do not impact the AFUE rating, DOE is considering including 

in this test procedure a performance test to demonstrate that the “automatic means” functions as 

required. While this test would not need to be performed by manufacturers to certify compliance 

with the existing design standards, DOE would use this test to verify compliance with the design 

standards should a question of compliance arise. DOE invites input on: 

(1)	 Any principles or tests currently used, or being considered for use, to qualify the 

operation of the automatic means. 

(2)	 Required inputs and types of technologies needed to project changes in demand and 

the relationships between these inputs/technologies and supply temperature or 

pump/burner operation. 

(3)	 Suggestions about the measurements that should be included in the test. 

E. Harmonization of Standards 

DOE invites input on other national or international test procedures commonly used to 

rate residential furnace and boiler energy efficiency, including the advantages and disadvantages 

of those test procedures compared to the current DOE test procedure. In particular, DOE seeks 

input on: 

16 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(1)	 Differences in efficiency performance caused by differences in minimum static 

pressure requirements in ASHRAE 103-200711 (Table IV) compared to DOE’s

proposed furnace fan test procedure,12 and drawbacks or advantages associated with 

harmonizing the requirements. 

(2)	 Any other national or international test procedures that could be considered for this 

cycle of test procedure amendments. 

F. Alternative Methods for Furnace/Boiler Efficiency Determination 

DOE is aware of alternative methods to measure the heating efficiency (AFUE) of 

residential furnaces and boilers. In particular, DOE seeks input on: 

(1)	 Procedure developed by Brookhaven National Laboratory that uses linear 

input/output, a relationship between fuel input and heat output that can be used to 

determine the efficiency of residential boilers.13 

(2)	 Any other methods that could be considered for this test procedure update. 

G. Scope 

A combination space-heating and water-heating appliance is defined in the applicable 

industry test standard as a unit that is designed to provide space heating and water heating from a 

single primary energy source. 14 The two major types of combination appliances are: (1) 

11 American Society of Heating Refrigerating and Air-Conditioning Engineers Inc., ASHRAE Standard: Method of 

Testing for Annual Fuel Utilization Efficiency of Residential Central Furnaces and Boilers (2007) Report No. 

ANSI/ASHRAE 103-2007. 12 See 77 FR 28674 (May 15, 2012). 13 Butcher, Thomas, Technical Note: Performance of Combination Hydronic Systems, ASHRAE Journal (December 

2011). 14 American Society of Heating Refrigerating and Air Conditioning Engineers, ANSI/ASHRAE 124-2007: Methods 

of Testing for Rating Combination Space-Heating and Water-Heating Appliances (2007). 

17 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

boiler/tankless coil or boiler/indirect tank combination units, whose primary function is space 

heating, and (2) water heater/fan-coil combination units, whose primary function is domestic 

water heating. Currently, there is no DOE test procedure for determining the combined 

efficiency of the combination products that can be used to supply domestic hot water in addition 

to its space-heating function. However, there are DOE test procedures for the individual 

components (boiler or water heater) of a combined appliance which provides for testing and 

efficiency ratings for the primary function - space heating or domestic water heating. 

DOE's test procedure for residential furnace and boilers, which is set forth at 10 CFR 

430.23(n) and 10 CFR part 430, subpart B, appendix N, addresses central gas-fired, electric, and 

oil-fired furnaces with inputs less than 225,000 Btu/h and gas-fired, electric, and oil-fired boilers 

with inputs less than 300,000 Btu/h. DOE's test procedure for residential water heaters, which is 

set forth at 10 CFR 430.23(e) and 10 CFR part 430, subpart B, appendix E, addresses gas-fired, 

electric, and oil-fired storage-type water heaters with storage greater than 20 gallons and gasfired and electric instantaneous-type water heaters with storage volume less than 2 gallons. 

ASHRAE has an existing test procedure, ANSI/ASHRAE 124-2007 (Methods of Testing for 

Rating Combination Space-Heating and Water-Heating Appliances), which provides a method of 

test to rate the performance of a combination space-heating and water-heating appliance.15 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 combination products. DOE seeks comment on: 

(1) What types of combination equipment are there in this market? 

15 American Society of Heating Refrigerating and Air Conditioning Engineers, ANSI/ASHRAE 124-2007: Methods 

of Testing for Rating Combination Space-Heating and Water-Heating Appliances (2007). 

18 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(2)	 How should DOE address the measurement of energy use by such combined 

products (keeping in mind the potential for active mode, standby mode, and off 

mode operation)? 

H. Standby Mode and Off Mode 

On December 31, 2012, DOE published a test procedure final rule in the Federal Register 

for furnaces and boilers related to standby mode and off mode energy consumption. However, 

given the broad scope of this 7-year-lookback test procedure rulemaking, comments are also 

welcome on DOE’s test procedure provisions for determining standby mode and off mode 

energy use. 

I. Other Issues 

DOE seeks comments on other relevant issues that would affect the test procedures for 

residential furnaces and boilers. 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 process. 

III.	 Public Participation 

DOE invites all interested parties to submit in writing by February 19, 2013, comments 

and information on matters addressed in this notice and on other matters relevant to DOE’s

consideration of amended test procedures for residential furnaces and boilers. 

19 
After the close of the comment period, DOE will begin collecting data, conducting the 

analyses, and reviewing the public comments. These actions will be taken to aid in the 

development of a test procedure NOPR for residential furnaces and boilers. 

DOE considers public participation to be a very important part of the process for 

developing test procedures. DOE actively encourages the participation and interaction ofthe 

public during the comment period at each stage of the rulemaking process. Interactions with and 

between members ofthe public provide a balanced discussion ofthe 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 Brenda.Edwards@ee.doe.gov. 

Issued in Washington, DC, on December 28,2012. 

Kathleen B. Hogan 

Deputy Assistant Secretary for Energy Efficiency 

Energy Efficiency and Renewable Energy 

20