## Tuesday January 17, 1989



# Part IV


# Department of Energy

Office of Conservation and Renewable Energy

10 CFR Part 430 Energy Conservation Standards for Water Heaters; Notice of Proposed Rulemaking and Public Hearing

### 1890 Federal Register 

## I Vol. 54, No. 10 

## I Tuesday, Jaunary 17, 1989 

## I**Propo~ed** 

### Rules

DEPARTMENT OF ENERGY

Office of Conservation and Renewable Energy

10 CFRPart 430

!Docket No. CAS-FlM-79-105]
Energy Conservation Program for Consumer Products; Notice of Proposed Rulemaking and Public Hearing Regarding Energy Conservation Standards for Water Heaters

AGENCY: 

### Office ofConservation and Renewable Energy, Department of Energy.
ACTION: 

### Notice ofProposed Ru!emaking and Public Hearing.

SUMMARY:

### The Energy Policy and Conservation Act (EPCA). as amended by the National Energy Conservation Policy Act, the National Appliance Energy Conservation Act of 1987 and the National Appliance Energy Conservation Amendments of 1988. prescribes energy conservation standards for certain types ofconsumer products. including waterheaters. Among otherprogram elements, the legislation requires the Department to establish standard methods oftesting covered products. In the case ofany amended test procedure. the Department is required to determine to what extent the proposed testprocedure would alter the measured efficiency.

OnMarch 13, 1987, the Department proposed to amend the test procedures for waterheaters. The Department of Energy (DOE) tuday is proposing to amend the energy conservation standards for waterheaters prescribed by EPCA. as amended, in order to account for changes in water heater measured efficiency resulting from amended waterheater test procedures. Today's proposal also includes the amended test procedure used to determine the proposed standard.

The purpose oftoday's notice of proposed rulemaking is to provide interested persons an opportunity to comment on the proposed rule. and to invite interested persons to participate in the rulemaking process. OATES: 

### Written comments (10 copies) in response to this notice ofproposed rulemaking must be received by the Department of Energy by March 20, 1989.

Oral views. data, and arguments may be presented at the public hearing to be held in Washington. DC, on March 9, 1989. at 9:30 a.m. Requests to speak at the hparing must be received by the iiilZ 

### "" £$£ 

### Departmentno later than 4:00 p.m., March 7. 1989.

Ten copies ofthe oral statement of each speakermust be submitted at the hearing registration desk the day ofthe hearing.
ADDRESSES: 

### Written comments (10 copies)are to be submitted to: U.S. 

### Department ofEnergy, Office of Conservation and Renewable Energy. CE-43.1 Hearing and Dockets, Water HeaterTest Procedure, Docket No. CASRM-79-105, Room 6B-025, Forrestal Building. 1000 Independence Avenue, SW

.. Washington. DC 20585, (202) 586- 9320.
FOR FURTHER INFORMATION CONTACT:



### Carl E. 

### Adams. U.S. 

### Department of

Energy. Office ofConservation and Renewable Energy, Forrestal Building. Mail Station CE-132, 1000 Independence Avenue, SW.• Washington, DC 20585. (20Z) 586-9138. U.S. 

### Department ofEnergy. Office of

Conservation and Renewable Energy. Hearings and Dockets. CE-43.1. Forrestal Building. Room 6B-025. 1000 Independence Avenue. SW

.. Washington, DC 20585. (202) 586-9320. Eugene Margolis. Esq.• U.S. Department

ofEnergy, Office ofGeneral Counsel, Forrestal Building. Mail Station GC12,1000Independence Avenue. SW.• Washington. DC 20585. (202) 586-9507.

SUPPLEMENTARY INFORMATION:

, I. 

### Background
Part B ofTitle III ofthe Energy Policy and Conservation Act (EPeA). Pub. L. 94-163. as amendedby the National Energy Conservation Policy Act (NECPA), Pub. L. 95-619, the National Appliance Energy Conservation Act (NAECA) of 1987. (Pub. L. 100-12) and the Natio!lal Appliance Energy Conservation Amendments of 1988 (Pub. L. 100-357) created the Energy Conservation Program for Consumer Products other than Automobiles. l 

### Thirteen consumerproducts subject to this program (often referred to hereafter

as "covered products") include water heaters. the subject oftoday's proposed rulemaking.

Under the Act. the program consists essentially ofthree parts: testing. labeling. andFederal energy conservation standards. The Department ofEnergy (DOE or Department). in consultation with the National Institute ofStandards and Technology (NIST). (formerly National Bureau of Standards). is required to

I Part BofTitle III ofEPCA, as amended. is referred to in this notice as the "Ac!." Pari BofTitle· 1lI is codifif,d at 42 U.S.C. 6201 Et s'''I· 

### amend or establish new test procedures

as appropriate for each ofthe covered products. Section 323. The purpose of the test procedures is to provide for test results that reflect the energy efficiency. energy use. or estimated annual operating costs ofeach ofthe covered products. Section 3Z3(b)(3). A test procedure is not required ifDOE determines by rule that one cannot be developed. Section 323(d)(1). One hundred and eighty days after a test procedure for a product is adopted, no manufacturer may represent the energy consumption of. or the cost ofenergy consumed by the product except as reflected in tests conducted according to 

### the DOE procedure. Section 323(c)(2). Testprocedures appear at 10 CFR Part 430. Subpart B.



### Section 323(e) ofthe Act requires DOE to determine to what extent. 

### ifany, a proposed test procedure would alter the measured energy efficiency ormeasured energy use ofany covered product as determined under the existing test procedure. 

### IfDOE determines that an amended test procedure would alter the 

### proposed standard. DOE is required to amend the standardaccordingly. In determining the amended standard, DOE is required to measure the energy efficiency orenergy use of representative samples ofcovered products which minimally comply with the existing standard. The average efficiency ofthese representative samples tested using the amended lest procedures shall constitute the amended standard.



### a. TestProcedures

The waterheatertest procedure was prescribed bynotice issued September 27.1977. (42 FR 54110. October4.1977). These original procedures coupled laboratory tests and calculations to obtain estimates ofenergy efficiency and annual energy consumption for storage type electric. gas and 

### oil water heaters. The laboratory tests consisted ofa "cold start recovery efficiency lest," which measured the ability ofa waler heater to heat cold water, and a "standby loss test." which measured the energy loss of a water heater when not providing heated water. Recovery efficiency and percent standby los3 are then mathematically combined in the calculations to obtain an energy factor, DOE's overall measure ofwaterheater efficiency. Also, the original**procedure~** 

### included calculations for determining the annual consumption and annual operating costs. DOE amended the waterheater test procedures by notice issued August 30. 1979. in order to prescribe a "measure ofa water heater's

### Federal Register 

## I VoL 54, 

### No. 10 / 

### Tuesday, Jaunary 17. 1989 

## I Proposed Rules 

### 1891

useful capacity called first hour rating," where useful capacity is the maximum hourly demand which can be met by tho waterheater. (44 

### FR 52632. September 7. 1979).

By notice published in the Federal Register on February 8, 1984 (referred to hereafter as the "1984 proposal"). DOE proposed to amend its test procedure for waterheaters. (49 FR 4870). Thepurpose ofthe 1984 proposal was threefold: First. to 

### extend coverage ofthe test procedure 10 

### heat pump waterheaters. a relatively

new waterheater designnotpreviously covered by the test procedure; second, to add a 

### method oftesting to determine the first hour rating ofwaterheaters equipped with thermal compensating dip tubes; and third, to make modifications
to 

### the lest procedures that would yield

more accurate determinations ofenergy efficiency and cost ofoperation for gas, oil and electric storage waterheaters.

By notice publishedMarch 16, 1984, DOE, on request of the waterheater industry. extended the comment period 42 days and rescheduled the March 15. 1984. public hearing to April.26. 1984. (49 FR 10071.)

In comments received in 1984 and throughout 1985 numerous parties requested that DOE.withdraw the 1984 proposal and wait until a more comprehensive proposal could be developed. Most notably, on 

### October 2- 3.1985, DOE andNISThosted a forum

on testing andrating.procedures for

consumerproducts which was attended by manufacturers. utilities. States. and public interestgroups. Atthe forum.

.there was unanimous agreement that DOE should withdraw the 1984 proposal and initiate the development ofa single test procedure method whichwould be applicable to all types ofresidential type waterheaters. including the instantaneous type ofwaterheaters.

By 

### notice publishedMarch 13. 1987 (referred to hereafter as the "March 1987 proposal"J. DOE proposed a single test procedure for all types ofwaterheaters. including instantaneous type water heaters. The March 1987 proposal also addressed the matter offour test procedure waivers where four manufacturers of waterheaters had received allowance to test certain water heaters under modified test procedures. Since publication ofthe March 1987 proposal, 

### a fifth manufacturer has received a 

### test procedure waiver. The March 1987proposal would extend these modifications to all manufacturers 

### ofsimilar designs and thereby would terminate the five individual waivers. The five waivers are: A.O. Smith Corporation fOl: its 

### gas waterheaters t'q

### uipped with thermal compensatingdip 

### luhes (47 FR 53942. November 30. 1982), and four manufacturers ofwaterheaters withJarge thermal mass designs: Bock Water Heaters Inc. (50 FR 47106. November 14. 1985, modified51 FR 21975. June 17. 1986), Ford Products Inc.

. (50 FR 50678. December 11,1985,

modified 51 FR 18659. May 21, 1986), Lochinvar WaterHeaters. Inc. (51 

### FR 22966. June 24, 1986). and Aero Environmental Limited (53 FR 9687. March 24. 1988).

.

The major issues covered in 

### the March 1987 proposal included:

(1) Extending the test procedme to

cover heat pump waterheaters and instantaneous type waterheaters;

(2) Revising the method oftest for all waterheaters from a no draw test to 24 hour simulateduse test which includes a 

### six-hour drawtest; and

(3) Revising the first hour rating test from a calculated estimate to a direct

measure for determining a water heater's ability to supply hot water. 

### b. Ellergy Conservation Standards

The National Appliance Energy Conservation Act of 1987 prescribed energy conservation standards for 11 

### types ofappliances including electric, gas. and oil-fired waterheaters. The effective date for waterheater standards is January 1" 

## lImO.

NAECA also, added a definition fDr 

### walerheaters. as follDws: "The term 'waterheater' means a product which utilizes oil. gas, orelectricity to heat potable waterfor use Dutside the heater upon demand.including-

(A)Storage type units whichheat and storewater at a thermostatically controlledtemperature, including gas storage waterheaters with aninput of 75,000 Btu perhour orless. oil storage waterheaters with an input of 105,000 Btu perhour orless, and electric storage waterheaters with an input of 12 kilowatts orless;

(B) 

### Instantaneous type units which heat waterbut CDntain no more than one gallon of waterper4,000 Btu perhour of inpnt. including gas instantaneous water heaters with an input of200,000 Btu per hour orless, oil 

### instantaneous water heaters with an

### input of

### 210,000 Btu per· hour or less, and electric instantaneous waleI' heaters with aninput of 12 kilowatts orless; and

(C) 

### Heat pump type units. 

### with a maximum currentrating of24 amperes at 

### a vDltage no greater 

### than 250 volts. which are products designed to 

### transfer thermal energy from one temperature level to 

### a higher temperature level for the purpose of

### heating water, including all ancillary equipment such as fans. storage tanks. pumps, or contro,ls necessary for the device to performits function." Section- 323(e) ofthe Act requires DOE to determine to what extent. if any. a 

### proposed test procedure would alter the measured efficiency ormeasured energy
use ofany covered product as determined under the existing test procedure. Today's proposal satisfies this requirement with respect to the March 1987 proposal. Furthermore, section 323(e) requires DOE to test 

### a representative sample using the propo,sed test procedure; today's proposaJ is based on testing a sample of units in accordancewith the March 1987 proposal which has been revised based upon the comments received. The revised test procedure used to test H 

### sample ofwaterheaters is included in Section

## n, Discussion, below.

Section 323(e) ofthe Act also provides that models Df

### covered products in use before the date on which the amended energy conservation standard becomes effective (or revisions ofsuch models thatcome into use after such date and have the same energy efficiency or energy use characteristics) that comply with the energy conservation standard applicable to such coveredproducts on the day before suchdateshall be· deemed to comply with the amended energy conservation standard.


## n. Discussion



### a: Standards
1. Efficiency Standards Prescribed by NAECA

. The NAECA standards, which are based on existing test procedures. are in 

### terms ofenergy factor. These are:

Energ,' factor

(A) Gas water heater.

.........62- (.OOI9xRated storage volume in gallons). (S) Oil water heater

............59·- (.OOI9xRated storage volume in gallons). (e) Electric water heater

....95- (.00132xRated storage volume in gallons).



### The second term in these equations. i.e.•.0019V and .00132V, accounts for thH effect oftank volume on energy factor. This relationship ofenergy factor to tank volume is due to the fact that with

a given c.onstruction (same insulation. etc.). the energyrequired to 

### maintain stored watertemperature increases with increased storage volume.

The coefficienrfor volume used in this 

### relationship, i.e., 0.0019 for gas and oilfueled waterheaters and 0.00132 for 

### electric waterheaters, is 

### the slope ofthe line which reJates energy factor to tank volume. The test methods in today's

### 1892 Federal Register / Vol. 54, No. 10 

# I Tuesday, Jaunary 17, 1989 / Proposed Rules

notice are not considered to alter the

measure o[efficiency ofwaterhealers from the existing test procedures. Therefore. DOE proposes to retain the volume relationships in the NAECA standards.

Since the data base oftest units used in developing these proposed water heater standards is a total of 14 units, i.e.• 

### 7electric. 5gas. and 2 oil water heaters. DOE requests any additional test data manufacturers may have and any information manufacturers may have on the effects oftank capacity on energy factor.

2. 

### Effects ofProposed Test Procedures

on Energy Factors

In accordance with the requirements ofsection 323(e) ofthe Act. the Department has reviewed the impact amended test procedures will have on the measure ofwaterheaterenergy efficiency. The following changes to the test procedures have been reviewed:

• Simulated use VB. 

### cold start test.

• Watertemperature rise.

• Stored watertemperature (thermostat

setting).

• Room temperature.

• Waterusage.
• Uninsulated pipe fittings.

Some ofthe above changes to the test procedures increase energy factor while other changes reduce energy factor. The overall effect is to reduce the energy factor for electric storage waterheaters, while the energy factor for gas and oil fueled storage waterheaters is not expected to be affected by the changes.

The test procedure. specified in today's notice-simulateduse testadjusts upward the energy factor for high mass waterheaters (such as oil fueled waterheaters) compared to the cold startrecovery test. Under cold start conditions ofthe existing testprocedure.

some ofthe energy input is used to heat up the tank (metal and insulation) to the operating temperature andis therefore not available for heating water. The procedures specified in today's notice do not include that condition.

Energy factors calculated using the test procedures in today's notice would also be expected to increase due to a reduced assigned temperature difference between stored water androom (emperature, i.e.• reduced from 90 OF in the existing procedures to 67.5 OF. With reduced temperature. lower standby loss results.

However. the overall effect on energy factor due to reduced stored water temperature would be neutral due to the reduction in energy output. The reduced temperature rise ofheated water, i.e.• from 90 OF to 77 OF, results in less energy output perday. and since energy factor drops as the energy output drops. this lower temperature rise tends to reduce energy factor (approximately two percent for an electric waterheater).

Another change which is applicable to all water heaters is the use of uninsulated pipe fittings in these new procedures. This change would increase standby loss and reduce energy factor. Electric waterheaters without heat traps would be particularly affected since all their energy loss isdue to standby loss.

Since no specific energy factors were prescribed spearately for instantaneous waterheaters. DOE believes the standards prescribed in NAECA for waterheaters are also applicable to instantaneous type waterheafers. However. the definitions usedin today's notice for instantaneous type water heaters include only residential types intended to supply the total residential hot waterrequirements and exclude commercial types.

The only known residential types of instantaneous waterheaters are gas fueled. either natural gas or Liquified Petroleum (propane) gas. The energy factor proposed in today's notice for gas fueled instantaneous waterheaters is based on an assigned nominalstorage volume oftwo gallons for all instantaneous waterheaters. Therefore, the second term in the NAECA equations for gas waterheaters, i.e., 0.0019V. is not relevant for instantaneous type waterheaters oftwo gallons or less. Since the maximum volume ofthe instantaneous water heaterhasbeen defined here to be no
more than two gallons. this term has little effect onthe energy factor. At the extreme with two gallons ofstorage, the calculatedresult using this second term would be 0.616 which the testprocedure rounds to 0.62.

Electric instantaneous waleI' heaters

are considered by DOE to be excluded from the program because they are primarily used in industrial and commercial applications to produce tempered, ratherthan hot. water and are not considered to beresidential.

Oil fueled instantaneous water heaters are not included in the proposed standards. NAECA's definition of instantaneous type units is for units that contain less than one gallon per4,000 Btu perhour ofinput. However, an oil fueled storage waterheater ofbetween 80.000 and 105.000 Btu perhour input with a tank capacity of20 to 26 gallons would fall into this definition of instantaneous waterheater. This configuration is more properly covered

as a storage type waterheater. Also. there are no specific energy factors for heat pump water heaters specified in NAECA. Therefore, heat pump waterheaters are not included in these proposed standards. Since heat pump waterheaters have an energy factor greater than 1.0 and energy factors prescribed in NAECA are all less than 1.0. the NAECA standard is considered to apply 

## to conventional electric waterheaters only. When reviewing the standards for water heaters in 1992. DOE will consider 

### if standards for heat pump water**hf~atel'S** 

### should be proposed.
3. TestResults

Waterheaters were selected for 

### test in orderto determine to what extent, 

### if any. the test procedures in today's notice would alter the measured efficiency ofwater heaters. The approach used to accomplish this was


### as follows:

Models ofthe most common water heater sizes in terms ofstorage capacity for gas, oil, and electric waterheaters

were selected. Electric waterheaters with a capacityrange of30 to 82 gallons, andgas waterheaters from 30 to 50 gallons are estimated to represent approximately 95 percent ofall electric andgas waterheaters sold. Units selectedfor test fall Within this range. Oil fueled waterheater selection is limited in terms ofstorage capacity. DOE believes the most common size oil fueled waterheaterhas a 32 gallon storage capacity; therefore, this size was 

### chosen for these tests.

The NAECA prescribed minimum conservation standards for selected storage capacities was calculated. For example. for 40 gallon electric water heaters the NAECA standard would require an energy factor of0.90. i.e., EF= 0.95-.00132V; substituting V=40. EF=90. Candidate waterheaters were identified by manufacturer and modHi number using the listings from the January 1987 Consumers Directory of Certified WaterHeaterEfficiency Ratings. which are certified and publishedby the Gas Appliance Manufacturers Association (GAMA). Test units selected for purchase were those listed in this directory whose rated energy factor minimally complied with the standard.

Five gas. six electric and two oil water heaters were purchased for testing. The gas andelectric waterheaters were tested at the National Institute of Standards andTechnology (NISTJ. and the oil fueled waterheaters were tested at the Electrical Testing Laboratory (ETL) in Cortland. New York. The oil fueled waterheaters were not tested Hi

### Federal Register 

## I Vol. 54, No. 10 

## I Tuesday, Jannary 17, 1989 

## I' Proposed Rules 

### 1393

.NIST, because NIST did not have the facilities to tesl these units. ETL was selected byNIST to test the oilfueled waterheaters because ofits experience testing these units for the GAMA water heater certificationprogram.



### Tables I, 2 

### and 3 

### show results obtained for electric, gas and oil fueled storage-type waterheaters. and the make and model number ofthe test units. The column labeled "Current Procedure" is the test procedure upon which NAECA standards were based.

Table 1 for electric waterheaters shows that test procedures used in today's notice resultin energy factors which are consistently lower than thai obtained with the current test procedure. The average dUferelH:e is .023. Therefore, 

### the first term of the proposed energy factor equation used in tociay's notice has been adjusted downward bv .02 in order to accollnt for this differenc;e. No effect of tank capacity is discernible in the limited amount oftest data shownhere. Comments in the form ofmeasured tcst data including energy factor for various tank capacities is requested.

Table 2 for gas waterheaters shows there is essentially little or no difference

on average between the current test procedure and the procedure used in today's notice. Therefore, DOE is not u proposing amendments to the energy fHctor for gHS waterheaters as prescribed in NAECA.

Table 3 for oilv\mtel' heaters also shows essentiallv the same results fur the test procedu;e used in toelay's nolice

versus the currenttest procedure. Although the simulated use lest granted by waivers used three draw cycles

versus six draw cycles in the procedures used in today's notice, the results show

no difference when rounded to the second decimal place as shown in Table 3. DOE is proposing not to amend the NAECA standardfor oil fueled water heaters.

TABLE 1.-TEST RESULTS-ENERGY FACTORS FOR ELECTRIC WATER HEATERS

A-I

A-4 

### --.-..**~-. ~** **-.-----.--.-.---.---~---.-** 

### ..----.-----.--...**~_.,__-------------r---'---"~--------'~--"'---'"** Tank capacity gallons Energy Factor 2
Tesl unil' Test Current tesl Rated Measured procedure in

._

..____.____.__. __...... _ ..___....________. __.._ ..._._._._....__

### ~-.---.--_-.~---- ______

### ~t-o-d~aY~'sn.-o-ti-ce~--~ __

o-ce-d-u_re

.. 3

....

### -+_

30 52 82 40 40 21.3 49.0 77.3 36.3 36.6 35.B 0.84 O.BB .89 .80 .84 .85 .B6 .BB .82 .85 GAMA directory rating"

0.91 .89 .84 .90 .90 .90

# :fu~~

....--.---------.---

____________ ... __L._

...____ ._____-L-.

__.

____---1

___ ....... ___._ ...

,.Test units by make and model'were as follows:

Test unit

A-I Manufacturer

Industries Roebuck & Company State Industries Sears Roebuck & A.O. Smith Water

..................1 Rheem Manufacturirlg Model No.

Censible PV30 1LS1. Survivor Kenmore 625-320520. PX821RT1. 153.313470,**Rh,ef'rn"I:"~~** Standard B1VR40D

.

"The difference between the "GAMA DirectoPj Ratin,," and the NIST test results (current test procedure)· can be attributed. to several factors including manufacturing tolerance and**~odtlct** variabiliiy. For example: one unit was found to have a considerable amount of voids ·in. ils foamed·in insulation. Since losses f.or electric water heaters are controlled by the quantity and quality of. insulation, voids result in increased standby losses, thereby, redUCing the umt's energy factor: While Ina units all measured lower in,energy factor under the current test.procedure than,the, GAMA. Directory Rating, DOE does not beheve that the results for umts that minimally**compl~** with the standard, based on test, will differ from those DOE found. DOE believes that the differences in lest methods WIU· result In a two. pOint (0.2) difierence (on average) for electric storage water heaters. •

. "Current test procedure for electric and gas water heaters: is the test procedure in 10 CFR Pari 430 Subpart 8, AppendiX E. The GAMA Directory Rating is also based on this lest· procedure.

8-1 TABLE 

### 2.-TEST RESULTS-ENERGY FACTORS FOR GAS WATER HEATERS

.......

## _--------_

...



# _

...

### _._------------------.,-----------,.-------_._-----_._--_

...

Testunil' Tank capacity Energy Factor ._.,._-_

....**,-~-"-------~---** - -- T--

Rated Measured Test procedure in today's notice Curren! test I GAMA procedure 

# Idirectory rating



# ,**---I----~---**

28.3 .56

.. .56 • .57 2B.6 .51 I .56,

. .57 3R5· 0.55 O'5fL 0.55

47,9 .53 

### L· .53

. .54

_.______________________________ .....Jl-

_____ ..J...

_____ 3_B

..... O

....L.

______**.:~_.** ___**.~4.·** ___**~~5**

I Test units by make and model were as follows:

### 1894 Federal Register / Vol. 54, No. 10 

## I Tuesday, Jaunary 17, 1989 

## I Proposed Rules



# -

Test unit Manufacturer Model No. 

# 8-1

................................................................................................. Rheern Manufacturing Co

...........................................................**~~:~n: ~;:~~yF~~;~_226~40-7**  

## i=L:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

# ~:;~~~:~~~~:i:i~~i~~~:::::::::::::::::::::::::::::::::**:::::::::::::::::::::::::::::::: ~~1~~~;i:::~~!rGVF~~:;fT**  5

6-5

.......................................................................................................... A.O. Smith.............................................................................................. Energy Saver

# PGX40-202.

TABLE 

### 3.-TEST RESULTS-ENERGY FACTORS FOR OIL WATER HEATERS

Test unit'**~**___**Ta_n_k~a~~Cfl~Y~g~al=16~n~s**__

### .-i

__________**,-E_n_W~g~y_fa_ct_~~**________

Rated Measured Test procedure in today's notice Current test

. GAMA procedure 2 directory rating

C-1

.......................................................................................:..............................................**~** 29.5 0.52 C-2

..........................................................,........................................_ ..·_

..·_

..·_

..·_

..·_,

..·_

..·_

..·_·

.. _,,·_·

.._·"L

___ --1...,-

..___ 2_9.-:-4..L-

___ .4_9.-l-.

_____ .l--

___ .__ 0.52 0.53

.49 .51

1 Test units by make and model were as follows:

. :
Tesl unit Manufacturer Model No.

## t~::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::**~~~~i~~~~~~~°:ie~i~;"c~;p:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: ~~OE~~2.** 

2 Current test procedure for Ofl tueled watw healers is a Ihree draw similated use lexl granted 111 lesl procedure waIVers to aU manufacturers of oil fueled w<ller healers (51 FR 18659). The GAMA Directory Raling is also based on Ihese tesl procedure waivers.



### h. TestProcedures



### DOE Is setting forth herein the amended test procedure which incorporates changes made to the March 1987

### proposal and which was used to determine the proposed standards in today's notice.

. .

These amended waterheatertest procedures will be made final at the

same time the standard levels are made final for watel' heaters. These amended test procedures are not proposed here for comment except in regard to the manufacturers' ability to replicate the DOE methodology in complying with the

new efficiency standards.

1. 

### Discussion ofComments

Definition of Instantaneous Water Heaters. 

### Two manuf&cturers of instantaneous waterheaters. Robert Bosch Corporation (Bosch) and International Technology Sales Corpol'ation (ITS). commented that the March 1987

### proposal is confusing in that less than 20

### gallon tank capacitywould be included in the proposed definition of ' instantaneous ';vater heaters. (Bosch, No. 69, at 3, and ITS. No. 65, at 2).2

2 Comments on the rulemaking were given docket numbers.'For comments submitted in writing, citations provide the name ofthe organization, firm

or person who made the comment, the docket number assigned 10 the comment, and the page on which the comment. is found in the commenter'g submittal. For comments made In ornl presentations 

### These commenters suggested a definition ofinstantaneous water heaterS that is based on demand and the heating operation is activated by a flow ofwater. ITS commented that three National Codes classify an' instantaneous waterheater as having

one gallon ofstorage orless. ITS also commented that electric instantaneous waterheaters differ from gas water heaters ofthe same type due to the fact that the "electrics" are primarily used to produce tempered water,ratherthan hot water,forindustrial and commercial applications and should not be included within the scope ofthis proposedrule. ITS also commented that small point of

use electric storage systems along with small single task gas instantaneous waterheaters should be exempt from DOE regulations. ITS commented that 99 percent of

### its mini-storage type water heaters (1.33 gallon) are used in wet bars and in offices, while 99 

### percent of the electric instantaneous are used in industrial/commercial applications.

The definition ofgas fueled instantaneous waterheaters in the test pl'Ocedures included in today's notice includes only waterheaters intendeq to supply the residential hot water requirements and excludes small special purpose commercial type waterheaters.

at public hearings cilations provide the name of the ol'gariization, the date of the public hearing, and the page numberofthe official transcript ofthe'Public hearing where the comment is found. 

### With these exclusions, the typical water usage rate proposed for storage type household waterheaters will also be applicable to instantaneous gas type household waterheaters.

Hot Wale!' Usage. 

### The hot water usage proposed in the March 1987 

### proposal included four assigned hot waterusage rates. The majority ofwatel' heaters would have been assigned 60 gallons per day under that proposed procedure.

Thermar Corporation (Thermar) stated that 60 gallons per day should be the only usage against which all residential heaters be measured. (Thermar, No. 50, at 3).

The Natural Resources Defense Council (NRDC) commented that 60 gallons per dayis excessive for an average family size and suggested that 30 

### to 40 

### gallons per day is more appropriate. (NRDC, No. 51, at 2-5). 

### In addition. NRDC suggests an alternative table ofdaily hot wateruse. The NRDC proposal would place almost all residential waterheaters into either 30



### or 45 

### gallon per day usage categories, and the oil-fired water heaters would all be assigned 45

### gallons per day instead of60 gallons per day as proposed.

Bock and GAMA commented that the assigned value for annual usage for oil fueled waterheaters should be the first hourrating. (Bock, No. 28, at 1, and GAMA, No. 59, at 18).

### Federal Register / 

### Vol. 54, 

### No. 10 / 

### Tuesday, Jaunary 17, 1989 / Proposed Rules 

### 1895

The purpose ofthe first hour rating

was introduced primarily to select a waterheater that would satisfy

consumerneeds, and secondly as a way for comparing water heaters having similar capacity in terms oftheir ability to deliverhot water. The selection process ofdetermining a waterheater size thaI would be needed to supply the peak amount ofhot waterneeded in one hour involves adding up all the hot water uses expected in one hour, or highest expected use, and to purchase water heaterhaving a first hour rating equal to or close to this estimated maximum demand. DOE does not consider the total amount ofhot water that would be used in a day to be equivalent to this maximum one hour demand period. i.e., first hour rating, as proposing by Bock and GAMA.

The March 1987

### proposal included broad groupings offirst hour ratings (in 20 gallon increments) for an assigned value ofdaily hot waterusage. The

.proposal grouped most ofthe typical residential waterheaters within the 60 

### gallon per day usage group. Ifthe GAMA and Bock recommendations

were to be adopted, i.e., one gallon increments, every waterheater with a djfferent first hour rating would

### be rated

on 

### a different hot waterusage basis and labeled annual cost for waterheaters would differ due to different water usage rates. To assign the total amount ofhot waterthat would be used in a day to be equal to the maximum one hour demand period, Le., first hour rating, has

no basis. No field test data has been supplied by commenters to substantiate their proposal. Any relationship betweenpeak hourly use and average daily.use is unknown.

DOE considers that Bock and GAMA's proposed assigned values of daily hotwater use based on the water heatersfirst hour rating is also inappropriate for these additional

reasons:

(i} 

### The instantaneous waterheater is capable ofsupplying typically two gallons perminute ofhot water or 120 gallons perhour. It 

### would be misleading to assign this number ofgallons per day to a typical instantaneous water heater since daily waterusage cannotbe directly related to a waterheater's ability to supply short term hot water.

(E) Large electric storage tank water heaters may be used as offpeak power controlled type, and would typically be

-an 80 gallon tank with a 100 gallon first hour rating.These waterheaters would not typically use 100 gallons per day, ' and their first hour rating would be misleading as a measure ofdaily usage since a water heater capacity is sized to meet peak needs and not according to daily usage.

The national average use ofhot water in 1975 was determined to be 450 gallons perweek as a result ofmetered field test data and is the basis ofthe current test procedure assignment of64.3 

### gallons per day for a typical family offour. A more recent reanalysis by NIST ofthe daily hot wateruse has confirmed this amount (NBSIR 853220 "AReview ofEnergy Use Factors for Selected Household Appliances"), and recommended 60 

### gallons perday as a national average daily usage rElte. Furthermore, a NIST

### I DOE Appliance Forum held at NIST in 1985 concluded that various utility studies tend to confirm a figure in the range ofthe presently set value of64 

### gallons per day. The forum also concluded that any minor adjustment, Le., 60 

### gallons per day, would have little merit. Therefore, DOE has concluded that one typical average value ofhot wateruse, the currently assigned value of64.3 

### gallons per day, remains appropriate for labeling the average, annual cost for all household water heaters. Also, the calculation ofenergy factor is based on this assigned average usage value of64.3 

### gallons per day.



### FirstHourRating. Maus Technologies (Maus) commented that there has been a strong emphasis in the waterheater industry on designing electric water heaters by maximizing the capabilities ofavailable heat as hot water delivered. (Maus, No. 60, 

### at 2.) 

### DOE understands this comment to mean that for a given amount ofenergy input more hot water would be available for use. Maus contends that the increasedcapability of the double element waterheater does notshow up in 

### a comparison with 

### a single element electric waterheater under the proposed pI'ocedure. By assigning all electric waterheaters with their rated recovery rate, the March 1987 

### proposal assumed all input energy to be available as hot water during the balance ofthe hour after the initial draw

was completed. Maus contends that only a portion ofthe powerinput to the tank during the heating ofwater will be available as usable hot waterduring the

one hour test period unless the water heater is of a special design. Maus commented that Mor Flow Industries, a manufacturer ofwaterheaters, is about to introduce a special design ofstorage type water heater which will actually deliver the performance that would be attributed by the proposed first hour rating testto all wa'ter heaters. Maus contends that its improved waterheater design will 

### not be properly recognized since the March 1987 proposed procedure would allow a conventional waterheater to be biased with a high rating. Maus recommends modificaiton ofthe test procedure to maintain power to the heater throughout the testperiod. Furthermore, Maus recommends that instead ofcalculating the amount of additional hot waterproduced, water heaters be tested to measure the amount ofhot water delivered. Maus also contends its recommendations will allow consumers to properly "size" in selecting a smaller water heater tank volume, which because ofthe special design would make available as much hot water as a larger tank. This would allow for an energy savings due to the inherently lower standby energy with a smaller tank.

The March 1987 

### proposal terminated the draw when the outlet water temperature drops 20 OF below the initial temperature. Thermorise Company (Thermorise), a developer ofa new electric waterheater design. commented that the first hour rating test should be terminated when the outlet temperature reaches 105 OF independent ofthe starting temperature. (Thermorise, No. 55, 

### at 1 

### and 2). 

### Thermorise proposes that 

### the heating element or the burnerbe energized during thefirst hour test since this will be the case under operating conditions in the field. Thermorise also proposed a specific adjustment to the flow rate and draw schedule for electric waterheaters. Thermorise contends that the gas and oil-fired waterheaters are practically immune to flow rate while the electrics are affected due to their lowerrecovery rate, with power input limitation; due to house wiring atabout 5000 watts. The draw schedule Thermorise PI'oposes varies from 1.5 

### gallons perminute (gpm) for 

### the smallest electric waterhea:ters (20 

### gallons) to 3 

### gpm with larger tanks (about 80 gallons).

GAMA suggested an alternative draw test that would be an hour long which would determine the amount ofhot waterprovided in that period. (GAMA. No. 59, 

### at 7).



### NIST concurs with GAMA. Thermorise and Maus in their recommendations that a full one hour draw test be performed. In response to these comments, NIST recommended a revised test procedure for first hour rating. Thatrevised procedure, included in today's notice, consists ofallowing the powerto the waterheater to remain

on during the complete test and applying additional draws following the initial draw whenever the thermostat cuts out during the one hour test. At the end of

onehour, a:ny waterremaining in the ta:nkwhich is above a threshold floor temperature is drawn from the tank and credited for the first hour rating. The

### 1896 Federal Register 

# I Vol. 54, No. 10 / Tuesday, Jaunary 

### 17, 1989 

# I Proposed Rules

floor temperature for :terminatin.g the draw is assigned a value for testing purposes of25 degreesbelowthe maximum temperature ofwater drawn. An: adjustment ofthe number ofgallons ofthe water drawn to account for the average temperature ofwater drawnis calculatedin orderto express the results

as an equivalent volume at the maximum temperature (nominally 135 "F).



### Thermorise stated that a uniform draw rate of5gallons per minute for all waterheaters doesnot seem appropriate.and the rate should be2.5 gallons perminute for heaters rated 50 gallons orless. NIST recommended that lest procedures be kept as similar as possible for all waterheaters. The separate draw schedule proposed by Thermorise has notbeen aocepted. DOE has concluded that a draw rate ofthree gallons perminute is appropriate, and the draw rate is being revised to three gallons per minute for storagetype waterheaters.

Thermorise recommended a calculation procedure to adjust the amount ofwater drawn to an equivalent number ofgallons at a temperature of 135 OF. (Thermorise, No. 26, at**1~7.** 

### No. 70. at**1~3,and** 

### No. 73. at 1-4). The adjustment factorproposed by Thermorise is (Tom-(To-Td)/TdJ. where To is tht! maximum temperature ofthe drawn water andTom is the mean temperature ofthe drawn water. andTd is the temperature dr.op frpm the maximum to the floor temperature.**Th~rmorise** 

### proposed that no credit would be given for the water drawn until it 

### is heated above the floor temperature (nominally 110 OF or25 OF below the maximum 135 OF). The March 1987 proposal fur correcting the water volume used the inlet temperature of 58 OF as the reference point for correction. for a drop of.77 OF. In other words, credit was givenforheatingthe water from 58 OF. Thermorise subsequently withdrew its recommended 25 OFdrop, in favor .ofthe 77 OF 

### drop. (Thermerise, No. 73. at 1).

NIST has determined that the ferm 

### .01 the proposed adjustment equation recommended by Thermorise offers an improvement over the March 1987 preposal. Because the allowed variation ofthermostat setting for maximum temperature is 135 0 

### ± 5°, there couldhe

a slight variationinfirst hourratings due to the differences in thermostat setting from one unit to the next. The Thermorise preposed.adjustmentfactor eiiminates such differences .since the correction factor results in exactly the

same value irrespective offluctuations· in thp thermostat setting. This is due to the use ofan assigned tempel'8ture drep in both the numerator and denominator ofthe equation. The temperaturedrop is being assigned in these procedures as 77 OF (maximum .of 135 OF less the inlet .of58 OF equals 77 °F}.J·headjustment factor prescribed here'is ,(Tom"",(To-77)/ 77).

Several manufacturers and representatives .ofinstantaneous water heatermanufactures cDmmented concerning the proposed normaliz,ingof first hour rating using a five gallons per minute adjustment facter in the calculation. TheMarch 1987 proposal included adjustment ofthe first hour rating bya factor proportional to what would be supplied 

### ifthe testeddraw

were the same as used for storagetype water heaters (five gallons perminute). That adjustment would reduce the first hour rating by 50 percent for the typical instantaneous waterheaters.

The Contrelled Energy CorporatiDn (CE), The Carsen Agency (CA), Thermar, ITS, GAMA andBosch state that the 5gallons perminute flow rate specified is excessive and should be reduced to 3gallons perminute. ,(11'8, 

### No. iJ5, at 1-2. CA, No. 56, at 1; CE, No. 62, at 1; Thermar, No.5, at 3 and Bosch No. 69, at 5 and 6). The commenteNi believe that the first hour recovery factor should be equal to the number of gallons ofwaterdelivered in an hour with temperature raised 77 OF wUhout adjustment to a 5gpmrate as proposed byDOE. CE statesthatthe first hour recovery should be based enthe amount ofhot waterprovided at a given temperature. Bosch and ITs also noted that 64.3 gallons perday, the assumed daily usage ofhot waterin the current test precedure, is in contradiction with the adjustment factor used in the March 1987 proposal. Bosch also states that its customers are satisfied with a lower flow rate and will accept reduced flow for larger periods. Bosch alse states its custemers tend to be customers who have large hot waterdemands, such as large families who might require 4. 5, or 6 consecutive showers.in the morning or evening.

DOE agrees that the first hourrating

as a measure .ofutility may be better based upon a method andprocedures which are consistent with usage ofthe preduct. DOE agrees with commenters that the first hour rating be the amount 

### .ofhet water the waterheater is able .to deliver in one hour ofcontinuousdraw at a 77 OF temperature rise. Test

. procedures that are included in today's

notice are based .on the measured amount ofdrawn hot waterprovided, without.adjustment for flow rate. 

### Draw Schedule. Thermorise cemments that the six dr.aW schedule be revised to two·draws for electric water heaters, one to represent

### the total morning use and one to represent the total**eve~ing** 

### use. (Thermorise. No. 55, at 2). Thermorise comments this would reduce testing time. and although it 

### may not be representative ofthe actual use, would be warranted given thefact that heat transfer in an electric water heater is about 100 percent and recovery efficiency (which is being determined by draw schedule test) would not be any
more accurate with a more detailed draw schedule. Thermarproposed that draw be terminated when the outlet water temperature reaches 105 

### OF. Thermal' commented thatthe draw schedule for average residential use is not 6 equal10-gallon draws. but is one major draw consuming perhaps 66 percent ofthe proposed 60 gallons and

as many as 5 smaller draws consuming the balance. (Thermar. No. 50, at 3).

The draw schedules proposed by 

### Thermar and Thermorise would result iIl

a reduced storage tank temperature after the initial largedraw. Consequently. the tank being practically filled with cold water would have a considerabiy lower standby loss.

This initial large drawwouldresult in

a reduced standby energy use inconsistent with typical use in the home, and is estimated (by calculation using an assigned typical waterheater design for standby less) to resultin increase ofthe energyfactor by approximately 2percent. Thermar's contentioA thattwo-thirds orallwater drawn is drawnduring One major draw is not consistent with field testdata published by NIST. SAd the American Society ofHeating Refrigerating and Air Conditioning Engineers (ASHRAE) in conjunction with field testing by Ontario Hydro. The ASHRAE-Ontario Hydro Repert shows. at the 95 percent confidence level, that the maximum hourly use was approximately 12 gallons. Dr

### 20 percent ofthedaily hot water use. In results reported fer "selected high moming users." the maximum use over one heur was 25 percent ofthe total dailyuse.

DOE rejects the suggestion that the draw schedule be reduced. based on a review or the comments. The six eflua! draws are being retained for aU waler heaters.



### Simulated Use Test. In theMarch 1987 proposal. recovery .efficiency. was included for two purposes: (1) 

### To adjust the daily water heatereriergyconsumed in order to account ferdifferencesin the water temperaillre,**i.e~.** 

### energy centent .of a storage tank at the end oftest as

### Federal Register 

## I Vol. 54, No. 10 

## I Tuesday, Jaunary 17,**198~.1** 

### Proposed Rules 

### 1897

compared with the starting condition; and (2) to calculate the first hourrating. Theproposed method oftest for recovery efficiency was the ratio of output energy to input energy over a six hour test. which included six intermittent draws spaced one hour apart.

GAMA commented that all six ofthe draws should be conducted with each successive draw beginning as soon as thermal equilibrium has been attained

as a result ofrecovery from the previous draw. (GAMA, No. 59, at 6). GAMA contends that the computation of recovery efficiency from the proposed test procedure is not consistent with the

. current recovery efficiency since the energy measured during the first six hours ofthe test includes several minutes ofstandbyenergy lost between each draw. For waterheaters with significant standby losses and low recovery efficiencies. use ofthe current procedure will result in a significant
error, according to GAMA.

Comments also were received suggesting thatrecovery efficiency be retained in its current form. The California Energy Commission (CEC) requests thatrecovery efficiency and standbyloss be maintained as clear components ofthe test method since these values are both used in a proposed ASHRAE Standard test method (SPC124P) for combined space/waterheating appliances and CEC documents. (CEC, No. 57, at 1).



### Book commented that separate thermal efficiencies and standby loss calculations be retained, since they may be useful in predictingperformance ofa waterheaterin applications different from the test conditions used in the March 1987 proposal and in today's notice. (Bock, No. 28, at 2).

NIST investigated the GAMA proposal as well as other approaches to adjusting recovery efficiency so that standby energy would not be included in the six hour draw test period. As a result ofthese tests, NIST recommended that recovery efficiency for gas, oil and heat pump waterheaters be measured during the first draw ofthe six draw test. In this test, any difference in the tank energy contentbetween the start and end ofthe first draw is accounted for. DOE has concluded that since the recovery efficiency ofelectric water heaters with immersed heating elements is near 100 percent (less jacket andpipe fitting losses), electric waterheaters should be assigned a recovery efficiency of98 percent. This is consistent with the assignment of98 percent in the current test procedures.

The procedures included in today's notice require a test for recovery efficiency be run atboth maximum and reduced fuel inputrates ifthe water heater is equipped with a control device which provides for burner input modulation. These procedures specify that the six water draws be run with the burner operating at maximum input. Since the March 1987 proposal, NIST has reported test results for several makes ofinstantaneous waterheaters (NBSIR 87-3537, May 1987). The NIST tests show recovery efficiency to be dependent upon flow rate ofwater drawn. Flow rate affects burnerinput rate which affects the steady-state combustion efficiency because, with atmospheric type burners operating at a reduced burnerfiring rate, an increase ofexcess combustion airresults. Combustion efficiency is at its maximum at the maximum input rate and falls off atreduced burner firing rates.

In tests results reportedby NIST, recovery efficiency fell by up to six percentage points with reduced fuel input rates when waterflow rates were reduced.

There cim be any number ofwater flow rates from the minimum (1f2 

### gpm approximately) which initiates burner operation to four gpm.,The maximum is determined by ability ofthe water heater to produce usable hot water.

In order to prescribe a test which will reflect all potential burnerinput rates, the test procedures in today's notice, for units which modulate gas flow, prescribe thatthree ofthe six water draws be run with the burner operating at maximum input and three draws (four, five and six) be at the minimum input. The water flow rate specified for the maximum input is whateveris needed to achieve a temperature rise of 77 OF. Waterflow rate for the reduced firing rate is specified as that flow that maintains burner operation at the minimum fuel input. Total time of operation at reduced input rate is adjusted in order that one halfofthe daily output energy is produced with the burner operating atreduced (minimum) inputrate.

Average recovery efficiency for modulating type burners is calculated as the average energy output to input energy for draws No.1, run atmaximum fuel input, and No.4, run at minimum fuel input.

Both Thermar andITS commented that instantaneous waterheaters do not result in standby loss since there is no storage; therefore, the test procedure proposed for recovery efficiency and the need to monitor room temperature is not needed. (ITS. No. 65. 

### at 3. 

### Thermar. No. 50, at4).

NIST has recommended in its analysis ofcomments that the six draw test procedure and the 18 hour standby period should be retained for instantaneous waterheaters so that testing ofall waterheaters is performed under the same set ofconditions.

Both ITS andThermar contend that for testing waterheaters all that is really necessary to determine efficiency is a· thermocouple to record incoming and discharge watertemperatures along with meters to measure energy consumed. This would mean only recovery efficiency would be used as a
measure ofenergy efficiency ratio.

DOE rejects the simplified single draw test or steady-state test. With a single draw the energy storedin the heat exchangeris lost during burner off periods. In a single draw or steady-state test, these cyclic losses are not accounted for. Also, the intermittent draw is more representative ofhow the waterheateris actually used.

The difference between energy factor for 24-hour simulated use test and recovery efficiency for a single drawis considerable. NIST reported, NBSIR 87- 3537 "Performance ofInstantaneous WaterHeaters," May 1987, energy factors ofbetween 10 and 24 percentage points lower than recovery efficiency at 64.3 gallons perday. The greatest difference between the four water heaters tested was for one having the highest pilot input rate, i.e., 896 Btu/hr. In otherwords, pilot input rate is expected to be an important factor in meeting the energy factor specified in NAECA and proposed today for gas fueled instantaneous waterheaters.

A standby test of18 hours prescribed in these procedures will reflect only the pilot loss, since there is practically no stored waterby definition for this type heater. Although instantaneous water heaters may be equipped with a valve to shut-offthe pilot and a manual start-up ignition source (such as a piezoelectric sparkignitor), procedures in today's notice are based uponfull use ofthe pilot energy in the simulateduse test andrequire the pilot to remain in operation. Standbyloss could be measured in a shorterperiod oftime for instantaneous type waterheaters. GAMA, in its comments,.suggests that the standby test may be terminated after

one hour and calculated for the daily energy use by multiplying the total hours for the daily standby period by that hourly loss.

GAMA also comments that the standby loss as a measure ofwater heaterperformance should be deleted from the testprocedure since theterm is not used or determined.**(GA~1A.** 

### No. 54, at19 and 28). CEC asks that the standby loss description be expanded to

### 1898 Federal Register / Vol. 54, No. 10 / Tuesday, Jaunary 17, 1989 / Proposed Rules

describe how to calculate standby loss, and "that it be retained as a clear component of the test method so that it ' may be used for other applications such

as ASHRAE standards." (CEC. No. 57, at 1).

The test procedure included in loday's notice provides details on how to calculate standby loss. The currentDOE test procedures define standby loss as a percent perhour term from which the actual loss as Btu perhour couid be calculated. Test procedures in today's notice express standby loss directly as the "Hourly Standby Loss" in Btus per hour. See Section 6.2.4 oftoday's notice under the "AmendedTest Procedure" (section 2 below). In order to maintain a consistentprocedure for all types of water heaters. the entire 24-hour simulateduse test is being retained.



### Correction of"MeasuredEnergy to Reference Temperature Conditions. The March 1987 proposal allowed temperature ranges for room air temperature of65-70 of. thermostat setting (average tank temperature at thermostat cut out) of 135±5 OF and inlet water of58 OF ±2 OF. At the
extremes ofthese conditions. with the most favorable being the lowest temperature differences between stored water and'room temperature. i.e., 60 OF. (130 OF less 70 OF), and the least favorable. 75 OF. (140 OF less 65 OF). the standby energy effects alone would

mean typical energy use variation of from 68.133 to 79.585 Btus per day. respectively. Energy factor would also be affected at these extremes. These conditions assume the inlet water termperature is held at 58 OF. The added tolerance of ±2 OF on inlet water would extend maximum energy use to 80.868 Btus per day with inlet water of 56 OF.

Procedures prescribedhere now include an adjustment of the measured recovery energy use to the required conditions of a 77 

## or temperature rise of the heated water (135 °F± 58 "F). Also, the standby energy use is adjusted from average measured temperature drop between the stored waterand test room to a required difference of67.5 OF (135 OF

± "F67.5 ·'F). The mid point ofthe allowable room temperature range of65 to 70 is 67.5 OF. These changes for correcting to reference conditions are ('xpected to correct in partproblems of repeatability oftest results raised by Ecod:Jlne in its comment. as detailed below.



### Repeatability.ofTest Results. Ecodyne commented that the wide variability of the tolerances for thermostat settings. room temperature and inlet water temperature will not allow for repeatability in testing. (Ecodyne. No. 63, at 4.) Ecodyne claims its test results with the same unit in six tests varied from an energy factor of0.83 to 0.92. Ecodyne believes that the existing test procedures give more repeatable results and should be retained.

Ecodyne commented that its plastic electric storage waterheaters. with bui.lt-in thermal mass, has more material to store heat than a conventional metal tank. Ecodyne claims that it can**~ake** 24 hours or more to balance heat flows and suggested that an option be provided to cycle a unit for a period-for stabilization before the, test is run.

NIST tested an Ecodyne manufactured plastic electric storage water heater and found no significant difference in energy factor between a test run without preconditioning, with the tank filled and with power on the thermostat adjusted. Although pre-conditioning ofthe tank

was intended for high mass oil fueled water heaters. ithas been included for any water heater 

### ifthat will improve repeatablity oftest results.

Ecodyne also commented that repeatability can be affected by air movement in the laboratory particularly with the exposed piping specified in the March 1987 proposed procedure. (Ecodyne, No. 63. at 2).

NBS has checked repeatability oftest results by these prescribed procedures and has determined that results are repeatable. However, a caution statementhas been added to the procedures in today's notice concerning protectingagainst drafts in the test area.



### Ratingsfor UntestedModels. Rheem Manufacturing Company (Rheem) proposed a calculationmethod to avoid the cost of testing each electric water heater having identical construction and tank capacity with the only difference being electric wattage ofthe immersed heating element. (Rheem. No. 71. at 1). Rheem proposes the value for 

### first hour rating and energy factor be determined for one particular input rating (wattage)

as the standard input. and these test results be assigned for all available inputs of that same tank design. As an example of the additional testing required. Rheem claims that a single series in its double elementproduct includes 40 combinations ofelements and that the most popular combination. 4.5 Kw elements. accounted for 85.62% of these sales. Since there are eleven different tank sizes in this series varying from 30 to 120 gallons. Rheem claims 440 tests would be required for ratingjust this one series.

In response to this comment. the tesl procedure includedin today's notice specifies that. in lieu oftesting. those water heaters having powerinput less than the manufacturer's designated h j
standard input. may be assigned, as the first hour rating. the number ofgallons removed from the tank in the first draw of the first hour rating test. Also, in lieu oftesting, water heaters with power inputs greater than the standard input rating, the first hour rating determined for the standard input may be used.

Similarly, energy factor for the identical electric storuge type waleI' heater with the exception ofheating eiement wattage may be assigned results for the standard water heater, i.e.• standard input rating. Since insulation of a specific electric water heater design is 

### all that determines the energy loss. the assignment ofthe energy factor to an identically constructed water heater would be technically correct.



### Piping Inlet aIld Outlet ConfiguJ'Otiol1. Ecodyne states that the heat loss from pipes should not be included when a waterheater is tested. (Ecodyne. No. 63, at 2). Ecodyne claims that the issue of piping should not be reflected in the performance ofa water heater.

GAMA recommended that the instructions on piping connections be revised to specify an arrangement of galvanizedpiping connections which includes two vertical runs ofat least 12 inches. a lateral run and several elbows. (GAMA. No. 59, at 11). GAMA recommends the use ofgalvanized pipe rather than copper tubing since galvanized pipe can be screwed directly

on to and offofthe water heater's water connections since all waterheaters have threated water connections. The configuration suggested by GAMA runs the water through two 90 OF turns before

a temperature measurement is taken. The additional bends serve to mix the water and provide a more accurate temperature measurement.

The NRDC.states t.itat the testing of water heaters with DOEproposed piping configuration represents a more accurate procedure for crediting heat traps than the system provided in the current regulations. (NRDC, No. 51, at 8).

The piping configuration adVOCated by GAMA essentially forms an external heat trap on both the inlet and outlet of the water heater which would tend to reduce thermal losses. Also, the use of galvanized piping is not typical in actual hot water installations and could affect test procedure results. NIST, however, advocates the use ofunions which will facililate the installation and removal of the copper water heaterpiping and proposes an arrangement which would insure adequate mixing ofthe fluid streams. DOE has determined that test procedures concerning piping configuration and test set up as

### Federal Register 

## I Vol. 54, No. 10 / Tuesday, Jaunary17, 1989 

## I Proposed Rules 

### 1899

provided in the March 1987 proposal are appropriate.



### Temperature Measurement of Stored

.ater. Ecodyne comments that its company experiences difficulty installing the thermocouple probe for measuring the water temperature within the storage tank. One lank which Ecodyne produces is 

### .all plastic and does not have an anode rod and related opening. The tCInperature and pressure reliefvalve opening is located above the heating element which prevents insertion of the probe at this location. The cold water inlet cannot be utilized because ofthe dip tube. Thus. Ecodyne contends. only the hot water outlet may be used and in so doing an extra Tfitting and elbow are required which adds extra mass and heat transfer surface area. Ecodyne further states that

on units supplied with heat traps,the heat trap must be moved. necessitating additional fittings which result in unrealistic test results. (Ecodyne. No. 65, at 2). Ford Products Corporation (Ford) also expressed concerns regarding the

use ofthe thermocouple probe at the public hearing on the proposed test procedures for waterheaters. (Ford, April 23, 1987. at 90). GI\MA recommended that the installation procedure for the thermocouple probe be modified to recognize that some storage 

### 1ks may not accommodate six .clrmocouples orhave an accessible protective 1;lnode in which the probe may be inserted. {GAMA. No. 59. at4). DOE agrees with these commen,ts and has changed the test procedures to reflect them.



### AmbientAir Temperature Measurements; ITS, CE and Thermar
state that ambient air temperature is not relevant in the testing ofinstantaneous waleI' heaters 

### and should not be required. (ITS. No. 65, at 4, Thermar, No. 50. at 3, CE, No. 62, at 2). CE and ITS commented that requiring the measurement ofambient temperature would cause undue hardship and may force several small companies to abandon theirefforts.

DOEbelieves the ambieHt air temperature surrounding an instantaneous water heater will.affect the performance of the water heater basedupon the design ofthe water heater. For example. an instantaneous water heater with a large heat transfer surface area, tested with a surrounding ambient temperature 

### of 100 cF. would be given an advantage over a unit of similar design tested with all ambient temperature of 65 OF. DOE acknowledges that for units currently on the market the effect ofambient temperature would be minimal. but believes that a uniform ambient temperature should be imposed for the testiHg ofall water heaters and this temperature should be recorded and reported. DOE does not concur with the commenters that measurement of ambient temperature forces an undue hardship on the manufacturers of instantaneous water heaters, since the
measurement 

### ofambient air temperature

can be easily performed with a relatively inexpensive thermometer having an accuracy of ±1 OF

..



### Flue and VentPipe Installation. GAMA recommended changes concerning the flue requirements for gas- and oil-fired water heaters. (GAMA, No. 55, at 9,10 and 12). Specifically, GAl\1A suggested the following installation requirements:

Forgas-fired water heaters having a vertically discharging draft hood outlet.

a five foot vertical vent pipe extension having a diameter equal to the largest flue collar size ofthe draft hood shall be connected to the draft hood outlet.

For gas-fired water heaters having a horizontally discharging draft hood outlet, a 90 degree elbow having a diameter equal to the largest flue collar size 

### ofthe draft hood shall be connected to the draft hood outlet. A five foot length ofvent pipe shall be connected to the elbow and orientedto discharge vertically upward. Perform all tests with the natural draft established 

### bv this length ofvent pipe. '

A water heater equipped with a mechanical draft system shall be installed with the mechanical draft system in accordance with the manufacturer's instructions using the minimum vertical and horizontal lengths ofvent pipe recommended by the manufacturer.

For an oil-fired \'\'8ter heater, establish

a draft at the flue coUar as recommended in the manufacturer's installation instructions. Establish the draft for oil-fired waterheaters with a verticallydischarging draft outletby using a sufficient length ofvent pipe connected to the water heater flue outlet ilnddil'ecled vertically upward.

For an oil-fired**wat\~r** heater having a horizontally discharging draft hood outlet, a 90 degree elbow having a diameter equal to the largest flue collar size of the draft hood shall be connected to the draft hood outlet. A length ofvent pipe sufficient to establish the draft shall be connected to the elbow fitting and orienled to discharge verticaliy upward. Direct vent oil-fired water heaters should be installed with venting equipment as specified in the manufacturer·s instructions.

DOE has adopted GAMA's recommendations in theirentiretv for oil and gas water heater vent

### requir~ments specified in loday's notice.



### WaterSupplyPressure. GAMA recommended that the specification dealing with supply waterpressure be modified such that the waleI' pressure need not be maintained between 40 psig and the maximum pressure specified by the manufacturer when water is being removed from the storage tank. (GAMA, No. 59, at 4).

DOE agrees with this GAMA recommendation. The following waler pressure requirement is contained withiH these prescribed test procedures: During the test when water is no! being withdrawn, the supply pressure shall be maintained between40 psig and the maximum allowable pressure specified by the water heater manufacturer.



### implementatJ'on and Timing. Thermar and CE request that at least two years elnpse between the formulation of a final test procedure and implementation of the procedure. (Thermar. No. 50, at4, and CE, No. 62. at 2). GAMA states that additional time is needed to evaluate the proposed revised test procedure. determine the transition ofthe Federal minimum efficiency requirements)o reflect the revised test procedure, and to conduct tesls to determine the new ratings ofexiHting water heater models. (GAMA. No. 59, at 2). GAMA requests

an interim rule, which in GAMA's opinion, would allow for a proper determination of the amendment to the Federal minimum standards and allow

some relieffrom the burden imposed by the combination ofnew test procedures and Federal minimum conservation requirements.

DOE believes this proposed rule, which includes the revised test procedure. should satisfy these
comments.



### otf-Peak liValerJ-if'ater..<;. A number of

### 1900 Federal Register 

## I Vol. 54, No. 10 

## I Tuesday, Jaunary 17, 1989 

## I Proposed Rules

comments 3 

### were received byDOE concerning "off-peak"waterheaters. Ohio Power Company states that the inclusion ofoff-peak storage water heaters in the DOE testing procedures would be most welcomed. This utility believes that the widespread use ofoffpeak storage waterheating is an efficientand cost-effective means of reducing growth in coincident peak demand. thereby delaying the need to construct new generating capacity.

Municipal Lighting Plant ofChicopee,

.Massachusetts commented that off-peak waterheating is a necessary part ofits energy management program. It

### urges DOE to find a way to test andrate this special design in a manner that gives the customer a fair comparison ofits advantages.

New England Power Service comments that off-peak waterheating is

an integral part ofthe Load Management andEnergy**Cons~rvation** 

### Program. Thus. it

### urges DOE to develop and implement tests designed to illustrate the energy conservation advantages of "off-peak" storage-type electric waterheaters.

Bozrah Light and Power Company also contends that off-peak water heating is a necessary part ofits energy management program. It

### urges DOE to find a way to test and rate this special design in a manner that gives the customer a fair comparison ofits advantages.

3 The following companies submitted comments supporting the development ofspecific tes,t procedures for off·peak water heaters:

Commenter Numb"r

Robert E. Cook

..............................::

......... 27. Northeast Utilities

..................................... 68. Kingsport Power Company..................... 48. Pubilc Service Electric and Gas Com· 49.

pany. Clinton Electric Cooperative Inc

............. 43 and 44. Lower Yellowstone Rival Electric As· 34.

soeiation Inc. Brown County' Rural Electrical 35.

Association. New York State Electric and Gas 36.

Corporation. The Frontier Power Company

................ 37. McClean Electric Cooperative

................ 38. City of Chicopee, Municipal Ughting 45.

Plant. New England Power Service

.................. 46 and 58. Bozrah Ught and Power Company

........ 47. American Electric Power Service Cor· 39.

poration. Illinois Electric Cooperative..................... 40. Thumb Electric Cooperative

................... 41. Joyland Power Cooperative, Inc.

.......... 42. Diluesne Ugh!........................................... 30. Corn Belt Electric Cooperative Inc

........ 31- Eastern Illinois Power

.............................. 32. Federated Rural Electric Association.... 33. Ohio Power Company

.............................. 64. Vaughn Corporation

................................. 66. Columbus Southern Power Company

.... 53. Indiana and Michigan Electric 54.

Company. 

### Kingsport Power Company comments that due to the benefits to both the customer andutility, it has implemented , a rate incentive which provides a lower energy cost where an "off-peak" water heaterisinstalled and operated during off-peak periods. Kingsport Power Company contends that "off-peak" storage waterheaters require specific testing methods. Once the appropriate test methods are developed. Kingsport Power Company believe they will verify the benefits of "off-peak" waterheating.

Public Service Electric and Gas Company recommends that strong consideration be given to determining a method to rate "off-peak" waterheaters in order to afford customers the opportunity to obtain a fair comparison ofthe advantages ofoff-peak water heating.

Columbus Southern feels that specific testing of "off-peak" storage type electric waterheaters is both warranted and desired. Columbus Southern cites ETL test results for "off-peak storage type electric waterheaters," which exhibited a marked improvement in energy factor over the same water heaters tested using the current DOE test procedures. Columbus Southern believes that efficiency testprocedures should exist for significant energy use concepts such as off-peak storage water heating.

Kentucky Power Company believes that DOE's consideration ofspecific testing for "off-peak" storage type water heaters is a definite step in the right direction. Kentucky Power. like Kingsport Power Company, has implemented a rate incentive which provides a lower energy cost to the customer for hot water heating. The company believes that "off-peak" water hellters require specific testing methods. and once the appropriate methods are developed. they will verify the benefits ofthis unique method ofwaterhe,ating.

The Indiana and Michigan Electric Company (Indiana andMichigan) believes that the implementation oftest procedures for "off-peak" storage type electric waterheaters would prove quite beneficial. This utility believes that the presentDOE test procedure does not compensate for the reduction in standby losses due to night time deactivation and temperature setback. Indiana and Michigan contends that off-peak electric waterheating plays a vital role in its commitment towards time ofday rates. It

### believes that measures ofenergy consumption for these controlled water heaters would help improve and standardize the design oflarge capacity and time differentiated storage type electric waterheaters. Edison Electric Institute agrees with DOE that the test methods developed for "off-peak" waterheaters should be restricted to electric waterheaters. Edison points out that more than 100 

### electric utilities have programs for electric waterheater control. and many others are investigating the institution of similar programs. Edison concludes by stating that there is a desire for better information on technological aspects of waterheaters, andDOE test procedures for "off-peak" waterheaters would be a welcome addition to these efforts.

Vaughn Corporation notes that there

are two test procedure areas which will have to be considered, standby loss and first hour rating. in order for controlled waterheaters to be integrated into the DOE waterheatertest procedure.

Vaughn states in its Hearing Testimony attachments that controlled waterheating has been in use for more than sixty years. (Vaughn. Apr 23.108). 

### Vaughn believes there are three areas that benefit from controlled water heating:

(1) Public policy is served because less energy is consumed to provide a service that is essential in every home.

(2) Electric utility energy management is servedbyreducing peak requirements and also by transferring that requirement to the period ofleast demand where resources may be under utilized.

(3) 

### The consumer is served through having a high quality service at a lower price.

Due to the numerous comments on this topic. NIST andDOE plan to explore various concepts for testing "offpeak" electric storage type water heaters. DOE expects to propose a rulemaking for controlled waterheaters upon completion ofthe NIST study.
2. AmendedTestProcedure

DOE is setting forth an amended test procedure which incorporates changes made to the March 1987

### proposal and' which was used to determine the proposed standards in today's notice.

The water heater test procedures in today's notice will be made final at the

same time the standard levels are made final for waterheaters. Test procedures

are not proposed here for comment except in regard to the manufacturers' ability to replicafe the DOE methodology in complying 

### witl: the new efficiency standards,

Uniform Test Method for Measuring the Energy Consumption ofWaterHeaters (as Found in Appendix Eto Subpart BofPart 430)

1.Definitions

1.1. "Cut-in" means the time or water

### Federal Register / Vol. 54, No. 10 / Tuesday. Jaunary 17, 1989 / Proposed Rules 

### 1901

temperature when a waterheater thermostat has acted to increase ,the eneegy or fuel input " the heating elements, compressor. or

nero 1.2. "Gut·out" means the time or water temperature when a water heaterthermostat has acted to·.reduce

# to a minimum the energy

or fuel input to the heatingele'menls, compressor, or burners to a minimum.

1.3. "Oesign Power**Rating~** means the nominal po\'lier rating that a waterheater manufm;turer assigns to a particular design of
waterheater, expressed in kilowatts or Btu per hour as appropriate.

1.4. "EnergyFactor" means a measure of
water heater overall efficiency in terms of energy output compared to energy consumption over a 24 hour usage cyele.

1.5. "First HourRating" means the amount ofhot wilter the water heater can supply in

one hour ofoperation.

1.6. "Heat Trap" means a device which can be integrally connected, or independently attached

..to the hot and/or cold waterpipe connections ofa wa.ter heater such that the device will develop.a thermal or mechanical seal to minimi<:e the recirculation ofwater due to thermal.convection between the water heater tank and its connecting pipes.

1.7. "Recovery Efficiency" means the ratio
to energy delivered to the water to the energy content of the fuel supplied to the water heater.

1.8. "Standby" means the time during which water is not being withdrawn from the
water heater

..There are two standby time intervals used within this test procedure:

T 'y, I represents the elapsed time between time at which the maximum mean tank h"aperature is observed after the sixth draw and the end of the 24 hour test; T'tbY. 2 represents the total time during which the
waterheater was in the standby mode uuring the entire 24 hour test.

1.9

.. "Gas fueled storage water heater"

means a water heater which utilizes gas as the energy source and which is designed to heat and store water at a thermostilticaHy controlled temperature ofless than lBO'F with an input of75.000 Btu per hour or less and a manufacturers specified storage capacity ofnot/eBs than 20 gallons nor more than 100 gallons.

1.10. "Electric storage waterheater" means

a water heater which utilizes electricity as the energy source and which is designed to heat and store water at a thermostatically controlled temperature ofless than 180"F with an input of 12 kilowatts or less and a manufacturers specified storage capacity of
not less than 20 gallons nor more than 120 gallons.

1,11. "Oil storage wuterheater" means a water heater which utilizes oii as the energy

source and which is designed tCl heat and
store water at a thermostatically controlled temperature ofless than 180'Fwith an energy input of 105.000 Btu per hour or less, and which has a manufacturers specified storage CApacity of50 gallons or less.

1.1.2. "Gas fueled instantaneous ;.vater heater" means a water heater which utilizes 's the energy source controlled manually .lton1atically by a water now activated control or a combination ofwater flow and thermostatic control. and which has an input greatel' than 50,000 Btu per hoUl' and less than 200,000 Btu per hour. and II manufacturers specified storage capacity of less than 2 gallons.., . : .

1.13. "Heat pump.water heater" means a**walf~r** heater**w~ich** utiliz.es electricity as the**el1f~rgy'solii'ce** with'a maxi'mufn current rating of24 amperes at

## avoltage no greater than 250 volts. and whichfsdesigned to transfer thermal energy from one temperature level to

a higher temperaturE level fur the purpose of heating water. including all auxiliary equipment such as fans. storage tanks.
pumps. or controls necessary for the device
to perform its function.

1.14

... ASHRAE Standard 41.1-74" means the standard published in 1974 by the American Society ofHeating, Refrigerating and Air-Conditioning Engineers, Inc. and titled Standard Measurement Guide: Section

on Temperature.Measurements.

1.15. "ASTM-D-215&-80" means the test standard publishedin 1980 by the American Society ofTesting and Measurements and titled Method for Smoke Density in Flue Gases from Burning Distillate Fuels,
2. Test Conditions

2.1 installationRequirements. Tests shan be performed with thewatel' heater and instrumentation.installed in accordance with section 4.

2.2AmbientAirTemperature. The ambient air temperature. shall be contrulled to Ii value between 65.0 'F and 70,0 OF on a continuous basis. For heat pump water heaters maintain the dry bulb temperature at 67.5±1 OF, Additionally, for heat pump waterhealers the relative humidity shall be maintained between 49 and 51 percent.

2.3. Supply Water Temperature. The temperature ofthe water being supplied to the water heater shall be maintained at 58±2 'F throughout the test.

2.4 Storage Tank Temperature. The
average temperature ofthe water within the storage tank shall be set to 135:t5 OF.

2.5 Supply WaterPressure. During the test when water is not being withdrawn. the supply pressure shall be maintained between 40 psig and the maximum aliowable pressure specified by the water heater manufacturer,

2.6. Electricaland/orFossilFuel Supply. 2.6.1. Electrical. Maintain Ihe electrical supply voltage to within ±1 percent ofthe
center ofthe voltage range specified by the
water heater and/or heat pump manufacturer.

2.6.2. NaturaJ Gas. Maintain the supply
pressure in accordance with the manufacturer's specifications. Ifthe supply
pressure is not specified, maintain a supply
pressure of 7 to 10inches ofwater column. If the water heater is equipped with a gas appliance pressure regulator. the regulator outlet pressure shall be within ±10% of the manufacturer's specified manifold pressure. Use natural gas with a higher heating value of approximately 1,025 Hiu per standard cubic fool.

2.6.3. Propane Gas. Maintain the supply
pressure in accordance with the manufacturer's spe,cifications. Ifthe supply pressure is not specified, maintain a supply
pressure of 11 to 13 inches ofwater column. If the water heater is equipped with a gas appliance pressure regulator, the regulator outlet pressure shall be within ±10% of the manufacturer's specified manifold pressure. Use propane gas with a higher heating vfliuf} d HpproximHtely 2.500 Btli per.standard cuhic foot.

2,ti.4. File/GilSupply. Maintain.an uninterrupted sup'ply of fuel oil. Use fuel oil with a heating value of approximately 1:m.700 Bill per gallon.
3. Instrumentation

3.1. PressureAJeasurements. Pressure mC[lsuringinstruments shal.! have an error no greater than the following values:

Item measured

,Gas pressure

...... fnstrument accuracy

±0.1 inch of Instrument precision

±0.05 inch ot water column. water column. Atmospheric ±0.1 inch of ±O.05 inch 01

pressure. mercury mercury column. column. Waler pressure

... ±1.0 pounds ±O.50 pounds .per squ8fe per square inch. inch.

3.2. Temperature !>leasureruent. 3.2.1. !>leasurement. Temperature
measurements shall be made in accordance with the standard**Mea~urcment** Guide: Section unTemperature Measul'ements. ASHRAE Standard,41.1-74.

3.2.2.AccuracyandPrecision. The
accuracy and precision of the instruments. including their associated readout devices. shall be within the limits as follows:

lns/rll- InstruItem measured ment ment accuracy precision

Air dry bulb temperature......... ±O.2"F I ±O.l "F. Air weI bulb temperature........ ±O.2 iliF. ±O.l 'f'. Inlet and outlet water lem-

.

peratures............................... ±O.2'F :1::0.1 'F. _S_to_ra_ 9 _e_la_n_k_t_e_m_p_e_ra.t.u_r_e_s_"_"L-_±_O_'_5'F ±0.25 'F.

3,2.3. ScaleDivision. In no case shall the smallest scale division ofthe instrument or instrument system exceed 2 times the specified precision.

3.2.4. Tempera1ure Difference. Temperature difference between the entering and leaving
water may be measured with any ofthe following:

a. A thermopile b. Calibrated resistance thermometers
c, Precision thermometers d. Calibrated thermistors

e. Calibrated thermocouples f. Quartz thermometers 3.2.5. Thermopile C0I18tmctioll. If a thermopile is used, it shall be made from calibrated thermocouple wire taken from a single spool. Extension wires to the recording device shali also be made from that same spool.

3.2.6. Time Consumt. The time constant of the instruments used 10 measure the inlel and ontlet water temperatures shall be no greater than 5 seconds.

3.3. Uquid nor\!JI,{easurements. The
accuracy of the liq'2:d now rClte measurement, using the calibration if furnished. shall be equal to or less than ±1% ofthe measured value in mass units per unit time.

3.4. ElectricEnergy. The electrical energy used shall be measured with an instrument and associated readout device that are accurate within ±% of the reading or 15 Wh, whichever is gr,wtCJ'.

### 1902· Federal Register 

## I Vol. 54, No. 10 

## I Tuesday, Jaunary 

### 17, 19B9/ Proposed Rules

. 3.5. Fossil Fuels_ The quantity offuel used by.the water.heater shall be measured with

·an instrument andassociated readout device that is aCGurate within: ±1% ofthe reading.

3.6. Mass Measurements. Mass measurements shall be made measured with instruments tha,t are accurate within ±0.10% ofthe reading of.O.l Ibm. whichever is greater.

3.7. Heating Value. The .higher heating value ofthe naturall;las, propane, or fuel oil shall be measured with an instrument and associatedreadout device that is accurate within ±1% ofthe reading. The heating value ofnatural gas and propane must be corrected for local temperature and pressure conditions.

3.8. Time. The elapsed time measurements shall be measured with an instrument that is accurate within ±0.5 seconds per hour.
4. Installation

4.1; WaterHeatingMaunting. A water heater designed to be free standing shall be installed according to the manufacturer's directions on a "!4 inch thick plywood platform supported by three 2x4 inch

runners. Ifthewaterheater is not approved for installation on combustible flooririg. ,suitable·non-combustible·matedal shall be placed between it and the platform; For heat pump water heaters without a storage tank supplied by the manufacturer. connections

. shall be made with a storage tank as

described in section 4.9.3 and in accordance with manufacturer-published installation instructions. The storage tank and heatpump section shall be placed on platform(s) constructed as previously described. If installation materials are not provided by the heat pump manufacturer. use uninsulated 8 foot long connecting hoses, having an inside diameter of% inch. Wall mounted water heaters shall be installed in accordance with manufacturer-published installation instructions on a simulated wall section made

, Jrom % inch plywood and 2 x 4 inch studs.

Placement in the test room shalLbe in an area protected fromdrafts.

.

4.2. WaterSupply. 'rhe water supply shall be capable ofdelivering water at conditions

as specified in section 2.

4.3. WaterInlet andOutlet Configuration. Inlet and outlet piping connections shall be configured as illustrated in Figure 1, 2. or3. Copper tubing, the same size as the connections on the water heater shall be connected to the tank and extend 24 inches in length.Unions may be utilized to facilitate installation and removal ofthe piping arrangements. A pressure gauge and diaphragm expansion tank shall be installed in the supply water piping at a location upstream ofthe 24 inch cold waterinlet pipe. An appropdatelyrated pressure and temperature reliefvalue shall be installed on all water heaters at the port specified by the manufacturer. Discharge piping for the relief valve shall be nonmetallic. Ifheat traps and/

orpiping insulation and/orpressure relief valve insulation are supplied with the water heater, then they shall be installed for testing. Clearance shall be provided such that none ofthe piping contacts other surfaces in the test room;

4.4. Fue/.oniJ/orElectricalPowerand Energy Consumption. Install one ormore instruments which measure, as appropriate, the quantity and rate ofelectrical en.ergy and/or fossil 'fuel consumption in accordance with section 3.

.

4.5. InterJ1(ii Storage Tank Temperature fl,Ieasuremenis. Install six temperature measurement sensors inside the water heater tank with a vertical distance ofatleast four inches between successive sensors.A temperature sensor shall be positioned at the vertical midpoint ofeach ofthe six equal volume nodes with the tank. Nodes designate the equal volumes used to evenly partition the total volume ofthe tank..As much as is possible. the temperature sensor should be positioned away from any heating elements, anodic protective devices. tank walls, and flue pipe walls. Ifthe tank cannot accommodate six temperature sensors and meet the installation requirements specified above. install the maxiInum number of

sensors which comply with the installation requirements. The temperature sensors shall be installed either through the anodic device

orreliefvalve opening. Ifinstalled through the reliefvalve opening, a tee fitting shall be installed such that the reliefvalve fitting is installed as·close as possible to its original

.. location. Added fittings shall be covered with

. thermal insulation having and Rvalue of4

hr.ft2.oF/Btu. '4.6.Ambient Temperature. The ambient air temperature shall be measured

. approximately at the verticalmid-point ofthe heater and approximately 2feet from the surface ofthe waterheater. The sensor shall be shielded against radiation.

4.7. Inlet and Outlet Water Temperature Measurements. Install temperature sensors in the cold-water inlet pipe and hot-water outlet pipe as shown in Figure 1. 2, or 3. as applicable.

.

4.8. Flow Control. A flow control valve shall be installed to provide flow as specified in within section 5.

4.9. Flue Requirements. 4.9.1. Oil-Fired WaterHeaters. Establish a draft at the flue collar as specified in the manufacturer's literature. Establish the draft by using a sufficient length ofvent pipe connected to the waterheaterflue outlet and directed vertically upward. For an oil-fired waterheaterhaving a horizontally discharging draft hood outlet. a 90 degree elbow having a diameter equal to the largest flue collar size ofthe draft hood shall be connected to the draft hood outlet. A length ofvent pipe sufficient to establish the draft shall be connected to the elbow fitting and oriented to discharge vertically upward. Direct vent oil-fired waterheaters should be installed with venting equipment as specified in the manufacturer's instructions. using the minimum vertical and horizontal lengths of vent pipe recommended by the manufacturer.

4.9.2. Gas-Fired WaterHeaters. Establish a natural draft in the following manner. For gas-fired wi!ter heaters haVing a vertically discharging draft hood outlet. a 5 foot vertical vent pipe extension having a diameter equal to the largest flue collar size ofthe draft hood shall be connected to the draft hood outlet. Forgas;fired waterheaters having a horizontally discharging draft hood outlet. a 90 degree elbow having a diameter equal to the largest flue collar size ofthe draft hood shall be connected to the draft hood outlet. A 5 footlength ofvent pipe shall be connected to the elbowand oriented to discharge vertically.upward.

Direct vent gas,fired wafer heaters shall be installed with venting equipment specified in the manufacturefs instructions using the minimum vertical and horizontallerigths of vent pipe recommended by the manufacturer.

_4.9.3. HeatPump WaterHeaterStarage Tank. The tank to be used for testing a heat pump waterhealer without a tank supplied by the manufacturer shall be an electric storage type waterheater having a volume of 47.0 gallons ± 1gallon with an Energy Factor of0.S7±.01 as determined in accordance with section 6.1.7 with two 4.5 kW heating elements controlled in such a manner as to prevent both elements from operating simultaneously.
5. Test Procedures

5.1. Storage Tank andHeatPumpWatel' Heaters.

5.1.1. Determinatian of Storage Tank Volume.·Determine the storage capacity. V.t • ofthe waterheaterunder test. in gallons, by subtractingthe tare weight-measured while the tank is empty-from the gross weight ofa full tank ofwater at 58 OF withall air eliminatedandline pressure applied as described in section 2.5 anddividing the resulting net weight by the density ofwater at 58 OF. 8.214 Ibm/gal.

5.1.2. Setting the Thermostatfor a Thermostatically Operated WaterHeater. Starting with a tank ofsupply water. initiate normal operation ofthe water heater. After cutout. observe the mean tank temperature (based on the six temperature sensors) every minute until the maximum value is observed. Determine whether this maximum value of the mean tank temperature is within the range of135 'F±5 OF. Ifnot. turn offthe water heater. adjust the thermostat. and refill the tank with supply water. Then. initiate normal operation ofthe water heater. and once again determine the maximum mean tank temperature after cut-off. Repeat this sequence until the maximum mean tank temperature after cut-out is within the range of135 °F±5 OF. Ifa waterheater has two thermostats. the thermostat which controls the upper heating element shalll be set first to yield a maximum water temperature of 135 °F±5 OF as measured by the temperature tank

sensors above the upper heating element. The thermostat which controls the lower heating element shall then be set to yield a maximum

mean tank temperature of135 °F± 5°F. For heat pump waterheaters. which control an auxiliary resistance element. the thermostat shall be set in accordance with the manufacturer's installation instructions.

5.1.3. PowerInput Determh,ation. For all v;aler heaters except electric types haVing immersed heating elements and initiate normal operation and determine the power input. P. to the main burners (including pilot light power, ifany) after 15 minutes of operation. Ifthe waterheater is equipped with a gas appliance.pressure regulalor.,the rpgulator outletprel!sure shall.be set within ±H)% ofthat recommended by the

. manufacturer. For oil fired water heaters the

### Federal Register / 

### Vol. 54, No. 10 

# I Tuesday, Jaunal'Y 17, 1989 / Proposed Rules 

### 1903

fuel pump pressure shall be within ±10% of the manufacturer's specified pump pressure. All burners shallbe adjusted to achieve an hourly Btu rating that is within ±2% ofthe value specified by the manufacturer. For an oil-fired waterheater, adjusted the burner to give a CO2 reading recommended by the manufacturerand an hourlyBtu rating that is within ±2% ofthat specified by the manufacturer. Smoke in the flue maynot exceed No.1 smoke as measured by the procedure in ASTM-D-2156-80. Gas- and oilfired waterinstantaneous waterheaters shall havethe burners adjusted to the manufacturer's maximum firing rate value.

5.1.4. FirstHourRating Test. Establish normalwaterheater operation with the maximummean tank temperature within the range specified in section 2.1.4. Withdraw wateruntil the electrical heater{s) and heat pump, ifpresent, orburner(s) are activated. Cease drawing water and wait until the thermostat has acted to reduce the electrical power orfuel input to the waterheater. Ifthe waterheater incorporates a heat pump, wait until both the heatpumpand electrical heating element(s) have ceasedto supply energy to the storage tank. Continue to wait until the niaximum storage tank temperature has been achieved. Record the time, oil, gas and/orelectrical meterreadings as appropriate. Do not interrupt electrical power and/orfuel to the wilierheater. The rate of waterwithdrawal shall be3.00±0.25gallons per minute. Draw and collect water withdrawn from the waterheaterin a suitable containerfor the purpose of determining its weight at the conclusion of the test. During the draw record the outlet fluid temperature begiiming 15 seconds after the start and at every subsequent 5 second interval throughout the duration ofeach draw. Alternatively, a water metermay be usedto directly measure the volume ofwater withdrawn. Record the maximum outlet temperature which occurs during the draw as T;""". The withdrawal ofwater shall continue until the outlet temperature drops to a value 25 OF below Tm.. " defined as Tm1no at which time the draw shall be terminated. Record the average outlet temperature and mass removed a8 tdol.rand M

.. respectively. Ifthe thermostat acts to reduce the supply offuel to the main burnerorelectrical input to the upperheating element ofa multiple element electric waterheater, or electrical input to a water heater having a single element or multiple elements which operate simultaneously, before one hourhas elapsed, initiate a second draw. During the draw record the outlet fluid temperatures beginning 15 seconds after initiating the draw and Ht every subsequent 5 secondinterval throughout the duration ofeach draw until the outlet temperature drops to Tmln, at which time the draw is terminated. Record the average outlet temperatures as well as the

mass removed. Continue this sequence of events until one hourhas elapsed, at which time power and/or fuel supplied to the water heater is terminated. Ifa draw is currently taking place, continue the draw until the outlet temperature reaches Tmin• Ifa draw is not taking-place at the end ofOlle hour, a final draw is conducted until the outlet temperature drops to a value ofTmin' In either case, record the outlet temperatures and the

mass removed during the final draw.

5.1.5;24HourSimulated Use Test. During the simulateduse test, a total of64.3 gallons

are removed. With the waterheater turned off, fill the waterheaterwith supply water and apply pressure as described in section 2.1:5.Turn on the waterheater and associated heat pump unit, ifpresent. Wait until cutout occurs at 135 °F± 5°P, as specified in section 2.1.4. After the cutout occurs, measure the mean tank temperature using the temperature sensors described in section 4.5 every minute until the maximum

mean storage tank temperature is achieved. The waterhealer maybe operated through up to three successive cycles ofdrawing 10 gallons per draw, permitting recovery between each draw, prior to the start ofthe lest. Record at this time (designated as 1'=0), the mean tank temperature

### r1'o), and the oil, gas, and electrical energymeasurements as appropriaie. Begin the 24 hour simulated use test by drawing an amount ofwaterout ofthe waterheaterequivalent to one-sixth ofthe daily hot waterusage, 64.3 gallons. Record the average storage tank and ambient temperature every 15minutes throughout the 24 hour simulateduse test unless recovery or
a drawis occurring. At elapsed time intervals ofone,.two, three, four and five hours from 1'=0, initiate additional draws removing an amount ofwaterequivalent to one-sixth of 64.3 gallons, with the maximum allowable deviation for any single draw being ±O.5 gallons.The quantity ofwaterdrawn during the sixth draw shallbeincreased or decreased as necessary such that the total volume ofwaterwithdrawn shallbe equal to 64.3±1.gallons.

Alldraws during the simulated 3.0±0.25 gallons perminute. Measurements of the inlet and outlet temperatures shall be made beginning 15 seconds after the draw is initiated and at every subsequent 5 second interval throughout the duration ofeach draw. The arithmetic mean of the hot water discharge temperature and the cold water inlet temperature shall be determined for each draw.Record the scale ormeter reading,

as appropriate, aftereach draw. At the end of the recovery period following the firs! draw. recoI'U the maximum mean tank temperature observed after cut-out, Tm..,1, and the energy consumed, Qrfor oil, gas, and heat pump waterheaters including auxiliary energy such

as pilot lights, pumps, fans, etc. Forheat pump water heaters Q

.. is the SUIll of the energy consumedby the heat pump and the electrical heating element(s}.

At the end ofthe recovery period following the sixth draw, record the total electric andl

or fuel energy consumption, Q.u, and the scale reading or the meterreading, 88 appropriate. Ifa water scale is used. determine the net weight of the water withdrawn, Ml'H1I ill pounds. Record the maximum value ofthe mean tank temperature after cutout as

### T.". Except as noted below, allow the water heater to remain in the standby mode until 24 hours have elapsed from the start ofthe test, r=O. Prevent the water heater from beginning a recovery cycle during the last hour ofthe test by turning offthe electric power to the electrical heating elements and heat pump, 

### if present, orby turning down the fuel supply to the main burner.at an elapsed time of23 hours. Ifa recovery is takingplace at an elapsed time·of23 hours. wait until the recovery is complete before reducing the electrical and/orfuel supply to the water heater.At M hours,record the mean temperature, 1'24, and the electric and/or fuel instrument readings. Determine the total energy consumption during the entire 24 hour simulateduse test, Q. Record the time intervalbetween the time at which the maximum mean tank temperature is observed afterthe sixth draw and the end ofthe 24 hour test as T.tby.l. Record the time during which waterwas not being withdrawn from the waterheaterduring the entire 24 hour period as T.tby,2.

5.2. Instantaneous WaterHeaters 5.2.1. Setting the OutletDischarge Temperature. Initiate normal operation ofthe
waterheaterat the full input rating. Monitor the discharge water temperature and set to a value of 135 OF ±5OF in accordance with the manufacturer's instructions. Ifthe water heateris not capable ofproviding 3.00 ± 0.25 gallons perminute then adjust the flow rate

as necessary to achieve the specified discharge watertemperature. Record the corresponding flow rate as VmOll•



### IftheillBtantaneOU8 water heater incorporates a controllerwhich permits continuous burneroperation at a reduced input rate, adjust the flow rate as necessary to achieve a discharge water temperature of 135 °F±5 OF while maintaining the minimum input rate. Record the corresponding flow rate, V Olin' Ifan outlet temperature of 135 °F±5 OF cannot be achieved at the minimum allowable flow raie permitted by the instantaneous waterheater, record the flow
rate as V min and·the outlet temperature as Tnlin•

5.2.2. Power lllputDetenninatioll. Foroil andgas flow actuated waterheaters, adjust the burners to the maximum firing rate value specified by the manufacturer.

5.2.3. FirstHoul'Rating Testfor Instantaneous WaterHeaters. Establish normal heateroperation at the maximum Input rate with thedischarge water temperature setin accordance with section 5.2.1. Record the time, oil, and/orgas metel's

as appropriate. Do 110t interrupt electrical 01' fuel to the wahlI' heater, Draw and collect water withdrawn from the water heater, while recording the inlet and outlet fluid temperatures beginning 15 seconds after the draw is initiated and at every subsequent 5 second interval throughout the dmation of the draw in a suitHble containerfor thp. purpose ofdetermining its weight at the conclusion ofthe test. Alternativelv, a wa(el' meter may be used to directly mea;Ul'e the value ofwater withdrawn. At the end ofone hour terminate the draw. Detcrmine the mass .ofwaterwithdrawn, MFHR, in pounds, or the volume ofwaterwithdrawn. VFIIR, in gallons with an error no greater than 2 percent.

5.2.4. 24 HourSimulated Use Test 5.2.4.1. FixedInputInstantaneous Water Heaters. Establioh normal operation with the discharge water temperuture amI flow rate set to values of 135 OF ± 5 OF and Vn>

... respectively. Record the oil, gas, and

### 1904 Federal Register / VoL 54, No. 10 / Tuesday, Jaunary 17, 1989/ Proposed Rules

electrical energy measurements. as appropriate. Begin the 24 hoursimulated use test by drawing an amount ofwater out ofthe water heater equivalent to one-sixth ofthe daily hoI water usage. 64.3 gallons. AI elapsed time intervals ofone. two. three. four. and five hours from T=O. initiate additional draws removing an amount ofwater equivalent to one-sixth of64.3 gallons. with the maximum allowable deviation for any single draw being ± 0.5 gallons.,The quantity ofwatel' drawn during the sixth draw shall be increased or decreased as necessary such ,that the total volume ofwater withdrawn shall be equal to 64.3± 1.0 gallons.

Measurements ofthe inlet and outlet water temperatures shall bemade beginning 15 seconds after the draw is initiated and at e\'ery'5 second interval throughout the duration ofthe draw. The arithmetic mean of the hot waterdischarge temperature and thp cold water inlet temperature shall be determined fl'lr each draw. Record the scale

or meter reading. as appropriate. aftpr each draw. At the end ofthe recovery period follOWing the first draw. record the energy consumed. Qr. Allow the water heater to remain in the standby mode until exactly 24 hours have elapsed from the start ofthe test. T=O. At 24 hours. record the p\ectric and/or fuel instrument readings. Determine the energy consumption during the entirp 24 hours simulated use test. Q.

[64.3) 77 OF 5.2.4.2. Variable fnplli Install/uneUlIs lll/ater Heaft?l's. Ifthe instantaneous water healer incorpomtes a controller which permits continuous burner operation at a reduced inputrate. the first three draws shall be conducted using the maximum flow rate. Vmax' while removing an amount ofwater equivalent to one-sixth of64.3 gallons. with the maximum allowable deviation for any
one ofthe three draws being ±0.5gallons. The second three draws shall be conducted
at Vmi

... Ifan outlet temperature of 135OF ± 5 °F could not be achieved at the minimullI flow rate permitted by the instantaneous waterheater. the last three draws should be lengthened such that the volume removed is equivalent to

V•.5 •S**.-.-----~".--** 

# [**---'--~.-** 

# 1

with the maximum allowable dcfinition for anyone of the three draw;sbeing ±0.5 gallons. The quantity ofwater drawnduring the siXth draw shall be Increased or decreased as necessary such thatthe total volume ofwater withdrawn shall be equal to 32.15+3*V •.5.s±1.0gallons. Measurements of the inlet and outlet weter temperatures shall be made beginning 15 seconds after the draw is initiated and at every 5 secorid interval throughout the duration ofthe draw. Determine the arithmetic mean ofthe hot waleI' discharge temperature and the cold
water inlet temperature for each draw. Record the scale or meter reading. as appropriate. after each draw. At the end of the recovery period following the first draw. record the energy consumption. Qr.max. Record the energy consumed prior to the fourth draw and at the'end ofthe recovery period following the fourth draw. Qr.min'

Allowthe water heater to remain in the standbymode Until exactly 24 hours have

, elapsed from the'start of the test. T=O. At 24 hours, record the electric and/or fuel instrument readings. Determirle the energy consumption during the entire 24 hour simulated use test. Q. '

6. Computations

6.'1 Storage Tank WaterHeaters.

whm'e M t is the mass withdrawn during the first draw. Ibm Cpl is the specific heat ofwater attha average temperature (TdeJ.l Tin.tl/2.Btul Ibm OF 'I'del.1 is the average delivery temperature for the first draw. OF T'n.1 is the average inlet temperature forthe first draw. OF

.
VB! is the storage tank capacity, gal 6 Tmln 58 'F

6.1.1. StOr(!3e Tank C£lpacily. The Rlorage tank capadty is computed using the follOWing:

VOl = (Wr - Wt}/p where Votis the storage capacity of the water heater. gallons

. Wr is the weight ofthe storage tank completely filled with water. Ibm W, is the tare weight ofthe empty storage tank. Ibm Pis the density ofwater at the appropriate temperature. Ibm/gal.
6.1.2. First HOll!'Rating' Complltati(}J/. Compute the first hour rating as

n MJf.el.j-{Tm ..-77 °F)) Fh , }; i=l p(Tmox--(Tm

.. x--77 °F])

Which may he expressed as

n MilT

### .e,.j

-- (Tma• - 77 'F)) Fh, l: i=l p[77 'F))

M. Cpl CTdel.t-'I';Il.d+V.tpCp' (Trnax.t-To ) 7/,**=-~-** Qr

pis the density ofwater at the average temperature (Tma•.• +'1'0)/2. Ibm/gal C,.z is the sppcific heat ofwater at the average temperature (Tmax•1+ Tol/2. Btu/ Ibm °F '1'0.

...1 is the maximum mean tank temperature recorded after cutout following me first draw. OF 

## to is the maximum mean tanktemperature recorded prior to the first draw. 'I" where Mi represents the mass removed during the ithdl'aw ofthe first hour rating test. Ibm Tdd

. 1is the average deliverytelnperature for the ith drawwhidhoccurredduring the first hour rating test. OF
T'nna is the maximum outlet temperature recorded during the first draw of the first hour rating test. 'I" p represents the density ofwater at the average delivery temperature. Ibm/gal and n represents the number ofdraws which

occur during the one hour period
ifa watermetef'is used in lieu of H scale. the fir5t hourrating is

77 OF

where Vi represents the volume removed during the ith draw ofthe first hour rating
test. gal

6.1.3. RecoveryEfficiency. The recovery efficiency for gas. oil. and heat pump storage lype,water heaters is computed as

und Q,is the total energy used

### oy the waler heater.between cutoutprior to the firs! draw and cutout following the first draw, including auxiliary energy such as pilot lights. pumps, fans. etc

.. Btu. (Electrical auxiliary energy shall be converted to thermal energyusing the following conversion -lkWh=3412;7(l Btu.)

The recovery efficiency for electric water heaters with immersed heating elE'mentsis HHsumed to be 911 percent.

### Federal Register 

## I Vol. 54, No. 10 

## I Tuesday, Jaunary 17, 1989 

## I Proposed Rules 

### 1905

6.1.4. HourlyStandbyLosses. The hourly Atandby losses are computed as

where Qhr is thehourly standby energy losses

.ofthe waterheater. But/hiQstby is the total energy consumedby the waterheaterbetween the time at which the maximum mean tank temperature is observed after the sixth draw and the end ofthe 24 hour test period. Btu M is the mass ofthe waterwithin the storage tank. Ibm

. Cp IB the specific heat ofwater at the avef!lge temperature ('1'24

### +T.u

### l/2. Btu/Ibm of 1'24 is the mean tank temperature at the end ofthe 24 hour test period. of 

### T.u is the maximum mean tank temperature observed after the sixth draw. OF and 7.tby.l is theelapsed time between the time at which the maximum mean tank temperature is observed after the sixth draw and the end ofthe 24 hour test period. hours The standbyheat 10s8 coefficient for the tank is computed as



### VA=

whereT;:.tbY is the average storage tank temperature between the time at which the maximum mean tank temperature is observed after the sixth draw and the end ofthe 24 hourtest period. Btu T•.8tb• is the average ambient temperature betweenthe time at which the maximum

mean tank temperature is observed after the sixth draw and the end ofthe 24 hour test period. Btu and UA is the standbyheat lOBS coefficient of

. the storage tank. BTU/hr of
6.1.5. Daily WaterHeating Energy Consumption. The daily waterheating energy consumption. Qd is computed as

'IIr

where 

### Qis the total energy used by the water heater during the 24 hours simulateduse test including auxiliary energy Iluch as pilot lights. pumps. fans. etc.• Blu 

### c" is the ,specific heat ofwater. Blu/Ibm 

### 'F M is the mass ofwater within the storage tank, Ibm 

### T

•• is the average tank temperature at the conclusion ofthe 24 hours simulated use test. OF 

## to is the average tank temperature at the beginning ofthe 24 hours simulated use test, recorded one minute before the first draw is.initiated OF· and 'IIr is therecovery efficiency ofthe hot waterheater, dimensionless. 6.1.6. AdjustedDaily WaterHeatiJlg Energy Consumption. The adjusted daily waterheating energy consumption. Qd3 takes into account that the temperature difference between the storage tank and surrounding ambient temperature may notbe the nominal value of67.5 of (135°F

- 67.5 OF) due to the 10 of allowable variation in storage tank temperature. 135 ± 5 of. and the 5 of allowable variation in surrounding ambient temperature 65 ofto 70 'F. The adjusted daily waterheating energy consumption is computed as
Q.i. = Qd

- 

### [(T.tb• - 

### 'f •.Blby)**~** (135 'P

- 67.5 °Fj]VA7.tby.2 where Qda is the adjusted daily waterheating consumption. Btu T.tb• is the mean tank temperature during the total standbyportion ofthe 24 hour test. 

### OF 

### T

•.•tb• is the average ambient temperature during the total standbyportion ofthe 24 hour test. OF VA is the standbyheat los8 coefficientfor the storage tank. Btu/hroF and 7.tby.2 is thenumber ofhours during which the waterheater was in the standbymode. during the entire 24liour test. hours A modification is also needed to take into account that the temperature difference between the outlet water temperature and supply water temperature may not be equivalent to the nominal value of77 ·F (135 OF

_ 58 OF). The following equations adjust the experimental data to a nominal 77 OF temperature rise.

The energy used toheat water, Btu per day, may be computed as

6 MIC.I(T<1<1.1-Tlil•l)
QIIW = I

1=1 '11K.

The energy required to heat the same quantityofwater overa 77 OF temperature rise. Btu per day. is

6 MjCPI(135 OF**~** 58 OF) Qmv.71 = I

1=1

The difference between these two values is
QUWD = QHW.77

- QHW which must be added to the adjusteO.daily waterheating energy consumption value. Thus. the daily energy consumption value which takes into account that the temperature difference between the storage tank and ambient temperature may not be 67.5 'f'and the temperature rise across the storage tank may not be 77 OF is Qdm = Qda 

### + QIIWD

6.1.7. EnergyFactoI'. The energy factor,

# B,. is computed as

6 .I
i=l MICpl (135 .1'- 58 OF)

. where Qdm is the modified daily water heating energy consumption as computed in accordance with Section 6.1.6. Btu where Mi is the mass withdrawn for ith draw (i = 1 to 6). lbm Cpl is the specific heat ofwater. Btul ibm "F.

6.1.0. AI/nualEnergy Consumption v

The annual energy consumption for storage type and heat pump waterheaters is computed as Eann••1 = Qdm * 365 where Qdm is the modified daily energy consumption**valli'~,** Btuper day and.365 is the number ofdays within a year, days.

6.2. Instantaneous Hot WaterHeaters. 6.2.1. FirstHourRating Computation. Compute the first hourruling as

M(Tder!Tm.. -77 OF))
p(Tm",,-{Tm ••

- 77 OF))

which may be expressed as

n M(Tde,-(Tmu-77 OF)) Ph. = .I i=l p(77 OF}

where M represents the mass removed during the one hour continuou8 draw,.Ibm

Tael is the average delivery temperature, OF; Tm

..is the maximum outlet temperature recorded during the draw. OF and p represents the density ofwater at the average delivery temperature. 1bm/gal.

Ifa water meteris used in lieu ofa SCll.le the first hourrutinS is computed as

V(,f del

- Tm8ll

- 77 OF))

77 'F

where V represents the volume ofwater removed during one hourcontinuous draw, gal

6.2.2. RecoveryEfficiency 6.2.2.1. FixedlnputInstantaneous Water Healers. The recovery efficiency is computed

as

'1/, 

## =

whereMI is the mass withdrawn during ill!) first draw. 1bm 

### c"t is the specific heat ofwater at the average temperature (1'001.1 

### + Tin.,J/Z, Btu/Ibm OF 

### 'r

d•I•1 

### is the average delivery temperatm!! 

### for the first draw. OF Tin,l is the average inlet temperature for the first draw, OF and

### Qr is the total energy used bythe waleI' heaterbetween cutout priorto the first draw and cutout following the first draw. including auxiliary energy such as pilot lights. pumps. fans. etc., Btu. 6.2.2.2. Variable InputInstantaneous Water Heaters. ForInstantaneous waterheaters which have a variable firing rate two

### 1906 Federal Register 

## I Yol. 54, No. 10 

## I Tuesday. JauI1nry 17, 1989 / 

### Proposed Rules**~~~~~~~~~~~~~~~~~~~~~~~---** recovery efficiency are computed. one al the maximum input rate and one Ht the minimum input rate. The recovery efficiency used in subsequent computations is taken as the
average of these two**value~,** The llla>;imllfll recovery efficiency is computed 00

where .11.1, is the mass withdrawn during lhe first draw. Ibm. C., is the specific heat ofwatel' at the
average temperature 

### (T.
e

### ',1 + 1"0.,)/2. Btu/Ibm 'F " 

### 1'''.1.1 is the average delivery wmperaiUw 1'01' the first draw. 'F 

### tin,' is the average iniellernpel'ature for the hrot draw.

## or: and Qr.m•• is the total pnergy used by the water hei"er betwt:en

The energy required 10 Ileal the saillP quantity ofwater over a 77 'f'**!!"mperalw~: I'i~e**  .is

i=1

The uiflel'ellce**L>(~l'wcen** these two valUE'S is QIlWIl Qmv.71

- QhW which must be added to the daily water heating energy consumption value. Thus. the daily energy cQnsumption value which lakes into accouni that the temperature rise across the storage lank may not be 77 'F is Qdm = Qd 

### + Qmvl>'

6.2.4. EnergyPoctur. The energy fH(:toL E" is computed as

6 MjC pj{135 "I"

- 58 OF) Ei I i=1

where**Q~<I'** is the daily water heating energy consumption as computed ill Hccordallcc with section 6.2.3. Btu, M; is the mass associated with theHh draw. Ibm, cutout prior to the firsl draw and cutout following the first draw, including auxiliary energy such as pilot light:;, Bt" The minimum recovery d'ficicncy is computed as

where M 4 is 

## tn,: mile'S wHhdl'HWTI durin!, tlU' fourth draw, Ibm.

c.,.. is the specific heat of water. Btu/lbmoF 

### i'd.l.. is Ihe average delivery temperature for the fourth draw. OF. 

### 'f,"., is Ihe average inlet temperature for the first dr<iw, 'F. and Q,.m.n is the total energy consumed immediately prior to the [oul'ih draw and cutout following th

.. lourth draw. including auxiliary energy such as pilot lights. Btu. rhe reC(lvery efficiency ,is computed a8



## c.' \8 the specific heal of' waleI' computed at <l temperatllre of (58 'I" + 135 °FJ/Z. Btul Ibm "I" 

## 1'".,.• is the averoge delivery temperatw'e for the Hh draw. 'F and

### t'n., is the average inlet temperature for the ith draw. OF. 6.2,5. AmlllolEnergy COIl.9umptiulJ. The ,iI1Dual energy cOllsumption for ins\antaneOUb type w81er heaters is computed as

Emlouill = -Qum

.... 8()5 where Qdm is the modified doily ene!'gy consumption. Btu per day (lnd 365 is th" number of <1ays within a v!:ar. days "

7. Ratings for llntestedMooel8

In order to relieve the tesl b\ll'den to 1ll8liUfac!urers ,\'110 offer wuter heaters which differ only in fuel type or power input, ratings lor uniested mude\s may lJP established in HccOl,dance with the following procedures. In Ikn ofthe following procedures a manufHcturer may elect to lest the Ullil 1'01' which a mting is sought

7.1 Gas l'Vuler Healers. Ralings outained lorgas water heaters llsing natural gas can be used for an identical water heater which utilizes propane gas if the inpnt ratings ilre within 10 percent 0.2.3. DiIl}Y v!'aWr Heating Enet:i!,t' CUIISUIlJptiu!l. The daily water heating energy consumption. Qd\is computed as Qd = Q where Qis the energy used by the flow clctuated water healer during the 24 hOllr simulated use les1.

A modification is**~Ilso** nefded to take into
dccotilli that the temperature difh,rence bet\l\'een the outlet \vater ten1pf3\"i::ture and bupply water temperature may lIGl be equivalent 10 the nominal vaiue of 77 <F [1:35 'F-58 "Fl, The following equalivns ;;djust HUe experimental da!" to a nominal 77 'F temperature rise.

'The energy used 10 heat WBtpr PHIY bp**c(1mpulerllJ~**

7.2 fo'Jt,('lriG IVuler l1euters

7.2.1 Pust HOll!'Rating. Ifan eledric**~torage** type water Iwater is available with

more than one input rating, the manufar;/urel' shall designate the standard input rating amI the water heater need only be tested with heating elements

## at the designstpo standard input rutings. The firs! hour rutings for units hoving power input rating less than the designated standard input rating shalllw Hssigned a first hour rating equivalent to HIR firsl draw of the first hour rating for the electric water hCHter with the standurd input raling. For units ha,,:ing power inputs greater than the designaled standard input rating, the l'irs! hOllr rating shall be equivalent to thaI measllrE'd for the waler Iwater I'\'Hh ill(: standard input rating,

7.2,2. f:neI;rJ,V FaGior. The energy factor for identical electriG storage type waleI' hf!Hters, with the exception uf heating element waliage. may use the energy fm;lo!' obtainf,d during t%ting of the water heater with !h!, designatf'd standard input wling,

BILLING CODE 6450-01-'"

### Federal Register 

## I Vol. 54, No, 

### 10 

## I Tuesday, January 17, 1989 

## I Proposed Rules

TO SCALE OR 

### • WATER METER Flow Regulator

TOUT

TO SCALE OR 24·**~~**

# _______**C~~==~T==~** /VATER METER

TO SCALE. OR Flow Regulator

G**c:~~~~~** WATER METER

v

....

lIHG CODE 6450-01-C Flow Regulator TOUT


# , r

24' I TOUT T'N

24·



### Figure 1

Figure 2

Figure 3 24· expansion Tank

Expansion

Tank

Expansion

Tank 

### 1907

### 1908 Federal

### Regist~r 

## I Vol. 54, No. 10 

## I Tuesday, Jaunary 17, 1989 

## I Proposed Rules

III. Environmental Impact, Regulatory Impact, Regulatory Flexibility,**Fe~eralism** 

### andTakings Assessment

.Reviews



### a. EnvironmentalReview

Pursuant to Section 7(c)(2) ofthe Federal Energy Administration Act of 1974, a copy ofthis notice has been submitted to the Administrator ofthe Environmental Protection Agency for his comments concerning the impact ofthis proposal on the quality ofthe environment.

The Department is proposing to amend energy conservation standards for waterheaters in accordance with amendments to test procedures for waterheaters.

TheDepartmentbelieves the proposed revision would not be environmentally significant since it wUI notresult in any environmental impacts.

For applications seeking a temporary small business exemption as well as for all petitions seeking exemption from Federal standards or supersession of State standards, DOE will conduct an appropriate National Environmental Policy Act (NEPAl review on a case-bycase basis.

The Departmentbelieves that the proposed action would not be a major Federal action significantly affecting the quality ofthe human environment within the meaning ofthe National Environmental Policy Act of 1969, and that neither anEnvironmental Impact Statementnor anEnvironmental Assessment is required for the propose rule.


### b. RegulatoryImpactReview

DOE has concluded that the rule is not

a 

### "majorrule" for purpose ofExecutive Order 12291 because it will not result in (1) 

### an annual effect on the economy of $100 million ormore; (2) a major increase in costs orprices for
consumers, individual industries, Federal. State or local government agencies, orgeographic government agencies. orgeographic regions; or (3) 

### significant adverse effects on competition. employment. investment. productivity. innovation, or on the ability ofUnited States-based enterprises to compete with foreignbased enterprises in domestic or export markets. This conclusion is based on two factors. First. this proposed standard is only transposing the existing NAECA standard levels due to test procedure modifcations. Second. the costs ofcomplying with the testing requirements on which the proposed rule is based are not significant. For example. there would be no additional testing costs dealing with waterheaters. lnstead, testing cost may decrease since the new test procedures reduce the test time from a 48-hour test to a 24-hour test.



### c. RegulatoryFlexibilityReview

The Regulatory Flexibility Act. Pub. L. 

### 96-354 (5 U.S.C. 601-612). requires that

an agency prepare an initial regulatory flexibility analysis to be published at the time the proposedrule is published. This requirement (which appears in section 603) does not apply ifthe agency "certifies that the rule will not, if promulgated. have a significant economic impact on a substantial number ofsmall entities." The proposed rule affects manufacturers ofwater heaters. Since the proposed rule does not affect the stringency ofthe water heater standards prescribed by NAECA, DOE believes that this rule would not have an affect onwaterheater manufacturers. including small manufacturers. Therefore. DOE certifies that the proposed rules. ifpromulgated, would nothave a "significant economic impact on a substantial number ofsmall entities."


### d. Federalism Review

Executive Order 12612 (52 FR 41685, October 30, 1987) requires that regulations orrules be reviewedfor any substantial direct effects on States. on the relationship between the National· Government and States. or on the distribution ofpower and responsibilities among various levels of government. Ifthere are sufficient substantial direct effects. thenExecutive Order 12612 requires preparation ofa federalism assessment to be used in all decisions involved in promulgating and implementing a regulation or a rule.

DOE has identified a substantial direct effect that today's regulation. whenfinalized, would have on State governments. It

### would initially preempt inconsistent State regulations. However, DOE has concluded that 

### the initially preemptive effect is not sufficient to 

### warrant preparation 

### ofa federalism assessment for 

### two reasons. First, DOE does not have discretion under the Act to avoid promulgating a preemptive regulation because ofa policy preference for State regulation as a general matter. Second. the Act provides for subsequent State petitions for exemption. which necessarily means that the determination as to whether a Statelaw prevails must be made on a case-by-case basis using criteria set forth in the Act. WhenDOE receives such a petition. it 

### will be appropriate to considerpreparing a federalism assessment consistent with the criteria in the Act. 

### e. "Takings"AssessmentReview
Executive Order 12630 (53 FR 8859, March 18, 1988) directs that, in proposing a regulation. an agency conduct a "takings" review. Such a review is intended to assist agencies in avoiding unnecessary takings that are necessitated by statutorymandate.

Forpurposes ofthe Order:
"Policies that have takings implications" refers to Federal regulations. proposed Federal regulations. proposed Federal legislation. comments on proposed Federal legislation. orotherFederal policy statements that. ifimplemented or enacted. could effect a taking. such as rules and regulations that propose orimplement licensing. permitting. or other condition requirements or limitations

on private property use. or that require dedications or exactions from owners of private property.

It 

### appears that there are three parts of the appliance standards program that could conceivablybe viewed ashaving "takings implications." These are testing (certification) requirements, the impacts ofstandard levels, and possible DOE testing ofproducts for validation.

This proposedrulemaking is concerned with the second part. namely the impacts ofstandard levels.

The impact ofstandards could be viewedby some as a "taking." Nevertheless. the Departmentbefieves that the fact that an energy conservation standardmay limit some manufacturers in the range of**appl~ance** 

### efficiencies that they can produce does not have "significant taking implications" in the

sense described in the Order. This notice does not change the impact ofthe NAECA standard.This proposal transforms an existing standard level as setby Congress in NAECA for water heaters to an equivalent level that would result only due to new testing methods being used to determine water heaters' energy factor.

IV. 

### Public Comment Procedure



### a. Participation inRulemaking.

DOE encourages the maximum level ofpublic participation possibie in this rulemaking. Individual consumers. representatives ofconsumergroups, manufacturers. associations. States or othergovernmental entities. utilities, retailers, distributors. and others are urged to submit written comments on the proposal. The Department also encourages interestedpersons to participate in the public hearing to be held in Washington, D.C

.. as provided at the beginning ofthis notice.

The DOE has established a comment period of60 days following publication ofthis notice. for persons to 

### comment on

### Federal Register / Vol 54, 

### No. 10' 

### {Tuesday., -Jaunary. 17,_ 

### 1989 

## I Proposed Rules 

### 1909

this proposal. All comments and the transcript ofthe public hearing will be available for review in the DOE 'edom ofInformationReading Room.
b. Written COJJ1JJ1entProcedures.



### Interested persons are invited to participate in this proceeding by submitting written data. views or arguments with respect to the subjects set forth in this notice. Instructions for submitting written comments are set forth at the beginning ofthis notice and below.

Comments should be labeled both on the envelope and on the documents. "WaterHeater Standards (Docket No. CAS-RM-79-105)." and must be received by the date specified at the beginning ofthis notice. Ten copies are requested to be submitted. All comments received by the date specified at the beginning ofthis notice and other relevant information will be considered by DOE before final action is taken on the proposedregulation.

All written comments received on the proposed rule will be available for public inspection at the DOE Freedom of Information Reading Room.

Pursuant to the provisions of 10 CFR 1004.11. any person submitting information or data that is believed to be confidential and exempt by law from lic disclosure, should submit one**,,~,nplete** 

### copy ofthe document, and 10 copies. 

### ifpossible. from which the information believed to be confidential has been deleted. DOE will make its

own determination with regard to the confidential status ofthe information or data and treat it 

### according to its determination.

Factors ofinterest to DOE, when evaluating requests to treat as confidential information that has been submitted, include: (1) A description of the item; (2) an indication as to whether and why such items ofinformation have been treatedby the submitting party as confidential, and whether and why such items are customarily treated as confidential within the industry; (3)

.whether the information is generally known or available from other sources; (4) whether the information has previously been made available to others without obligation concerning its confidentiality; (5) an explanation ofthe competitive injury to the submitting person which would result from public disclosure; (6) an indication as to when such information might lose its confidential character due to the passage oftime; and (7) whether " 'Iosure ofthe information would be ,e'public interest. c. PublicHearing. 1. ProceduresforSubmittingRequests
to Speak. 

### The time and place ofthe public hearing are indicated at the beginning ofthis notice. DOE invites any person who has an interest in these proceedings. or who is representative of

a group or class ofpersons having an interest, to make a written or telephone request for an opportunity to make an oral presentation at the public hearing. Such requests should be labeled both on the letter and the envelope. "Water Heater Standards (DocketNo. CASRM-79-105) and should be sent to the address, and must be received by the time specified. at the beginning ofthis notice. Requests may be hand-delivered to such address between the hours of 8:30 a.m. and4:30 p.m., Monday through Friday, except Federal holidays.

The person making the request should briefly describe the interest concerned and give a telephone number where he

or she may be contacted. Each person selected to be heard will be so notified byDOE as to the time they are requested to speak.

Each person selected to be heard is requested to submit 10 copies ofthe oral statement to the registration deskprior to the beginning ofthe hearing. In the event anyperson wishing to testify cannot meet this requirement, alternative arrangements can be made with the Office ofHearings and Dockets in advance ofthe hearing by so indicating in the letterrequesting to make an oral presentation.

2. Conduct of Hearing. 

### DOE reserves the right to select the persons to be heard at this hearing, to schedule the respective presentations, and to establish the procedures governing the conduct ofthe hearing. The length of each presentation is limited to 20 minutes.

A OOE official will be designated to preside at the hearing. The hearing will not be a judicial or evidentiary-type hearing, butwill be conducted in accordance with 5U.S.C. 553 and 556, and Section 336 ofthe Act. At the conclusion ofall initial oral statements, each person who has made an oral statement will be given the opportunity to make a rebuttal statement. subject to time limitations. The rebuttal statement will be given in the order in which the initial statements were made. The official conducting the hearing wili accept additional comments or questions from those attending, as time permits. Any interested person may submit to the presiding official written questions to be asked of any person making a statement at the hearing. The presiding official will determine whether the question is relevant. and whether time limitations permit it 

### to bepresented for answer.

Questioning ofspeakers will be permitted by DOE. The presiding official will afford any interestedperson an opportunity to question, with respect to disputed issues ofmaterial fact, other interested persons who have made oral presentations, as well as Federal employees who have made written or oral presentations, relating to the proposed rule. This opportunity willbe afforded after any rebuttal statements, to the extent that the presiding official determines that such questioning is likely to resulUna more timely and effective resolution ofdisputed issues of material fact. Ifthe time provided is insufficient orinconvenient,DOKwill consider affording an additional opportunity for questioning at a mutually convenient time; Persons interestedin makinguseof·this opportunity must submittheir request to the presidingofficialno laterthan shortly after the completion ofany rebuttal statements andbe prepared to state specificjustification, including why the issue is one ofdisputed fact and how the proposed questions would expedite resolution.

Any further procedural rulesregarding proper conductofthe hearing will be announced by the presiding official.

A transcript ofthe hearing willbe made and the entire record ofthe hearing, including the transcript. will be retained by DOE and made available for inspection at the DOE Freedom of Information Reading Room, Room lE

### 190, Forrestal Building, 1000 Independence Avenue, SW., Washinglon, DC, between the hours of 8:30 a.m. and4:00 p.m., Monday through Friday. For information concerning the availability ofrecords at the Freedom of Information Reading Room. call (202) 536-6020. In addition, any person may purchase a copy ofthe transcript from the reporter.

.List ofSubjects in 10 CFR Part430
Administrative practice and procedure. Energy conservation, Household appliances.

In consideration ofthe foregoing, it 

### is proposed to amend Part 430 ofChapter II ofTitle 10, Code ofFederal Regulations, as set forth below.

Issued in Washinglon, DC, Decembcf 30, 1988. Dr. John R. Berg, AssistuntSecretary Conservationol1d RenewableEnergy.

### 1910 Federal Register 

## I Vol. 54, No. 10 

## I Tuesday, Jaunary 17, 1989 

## I Proposed Rules

PART 430-ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS

1. The authority citation for Part430 is revised to read as follows:

Authority: Energy Policy and Conservation Act. Title III, Part B, as amended by National Energy Conservation Policy Act. Title IV. Part 2. National Appliance Energy Conservation Act of 1987. and Nationa1Appliance Energy Conservation Amendments of 1988 (42 U.S.C. 6291-{l309J

2. Section 430.32. as proposed on December 2. 1988 (53 FR 48825). is amended by adding paragraph (d) to read**a~** follows:

§ 430.32 Federal energy conservation standards.

(d) 

### Waterheaters.

Product class Energy factor January 1, 1990

1. Gas Water Heater ""

..... 0.62-(.0019 X Rated Storage Volume I in Gallons)

.. 2. Instantaneous Gas

Water Heaters. 3. Oil Water Heater

............ 0.62

.................................... 0.59-(.0019 X Rated

Storage Volume in Gallons)

.. 4. Electric Water Heater

.... 0.93-(0.00132 X Rated Storage Volume in Gallons)

..

I Storage tank capacity as defined in Appendix E to Subpart B of 10 CFR Part 430

.

. [FR Doc. 69-907 Filed 1-13-69; 6:45 am1

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