Energy Conservation Program for Consumer Products: Test Procedure for Water Heaters

DEPARTMENT OF ENERGY

Office of Energy Efficiency and Renewable Energy

10 CFR Part 430

[Docket No. EE-RM-94-230]

RIN 1904-AA-52

Energy Conservation Program for Consumer Products: Test Procedure

for Water Heaters

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

Energy.

ACTION: Proposed rule; limited reopening of the comment period.

-----------------------------------------------------------------------

SUMMARY: The Department of Energy (DOE or the Department) is amending

its test procedure for water heaters. The purpose of this notice is to

solicit comments on three amendments to the proposed test for rating of

instantaneous water heaters, the installation requirement for heat pump

water heaters supplied without tanks, and the definition of heat pump

water heater.

DATES: Written comments in response to this notice must be received by

December 1, 1997.

ADDRESSES: Ten copies of written comments may be submitted to: U.S.

Department of Energy, Office of Energy Efficiency and Renewable Energy,

EE-43, Room 1J-018, MS EE-43, ``Test Procedure for Water Heaters,''

Docket No. EE-RM-94-230, Forrestal Building, 1000 Independence Avenue,

SW, Washington, DC 20585, (202) 586-7574.

Copies of the comments and transcripts from the public hearing and

workshop may be viewed at the Department of Energy, Freedom of

Information Public Reading Room, U.S. Department of Energy, Room 1E-

190, 1000 Independence Avenue, SW, Washington, DC 20585, (202) 586-

3142, between the hours of 9:00 a.m. and 4:00 p.m., Monday through

Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Terry Logee, U.S. Department of Energy, Office of Energy Efficiency

and Renewable Energy, Mail Station EE-43, 1000 Independence Avenue, SW,

Washington, DC 20585-0121, (202) 586-1689, FAX (202) 586-4617,

[email protected]

Eugene Margolis, Esq., U.S. Department of Energy, Office of General

Counsel, Mail Station GC-72, 1000 Independence Avenue, SW, Washington,

DC 20585-0103, (202) 586-9507, FAX (202) 586-4116,

[email protected]

SUPPLEMENTARY INFORMATION:

I. Introduction

On March 23, 1995, the Department published a notice of proposed

rulemaking (NOPR) to make several revisions to its test procedure for

water heaters. 60 FR 15330. On July 12, 1995, a hearing was held on the

NOPR, and on February 12, 1997, a workshop was held. The proposed

amendments to the water heater test procedure included, among other

things, revisions to make the water heater test procedure applicable to

electric and oil-fired instantaneous water heaters, and definitions for

a heat pump water heater storage tank, an integral heat pump water

heater, and an add-on heat pump water heater. In response to the NOPR,

several commenters submitted proposals for alternatives to these

amendments. DOE is reopening the comment period to provide an

opportunity for public review and comment.

II. Discussion

A. Rating Instantaneous Water Heaters

In the NOPR, DOE proposed to extend coverage to include electric

and oil-fired instantaneous water heaters in addition to the gas-fired

instantaneous water heaters by amending the definitions and test

procedures. DOE proposed to use the first hour rating test (already

used for testing storage-type water heaters) for these instantaneous

water heaters.

The Department received comments from Bock, Edison Electrical

Institute (EEI), the Gas Appliance Manufacturers Association (GAMA),

and the Oregon State Energy Office stating that no oil-fired

instantaneous water heaters are manufactured for residential use.

Furthermore, the Federal Trade Commission does not receive labeling

data on oil fired instantaneous water heaters. (GAMA, No. 1 at 2;

Testimony from February 12, 1997, GAMA at 119, EEI at 119, Bock at 120,

FTC at 120; Oregon, No. 51 at 3.) DOE agrees and will withdraw coverage

for oil-fired instantaneous water heaters.

GAMA, the Electric Power Research Institute (EPRI), the Oregon

State Energy Office, and several utilities suggested that DOE's

proposed test for rating instantaneous water heaters be changed from a

first hour rating to a maximum flow rate in gallons per minute. These

commenters claimed the maximum gpm rating better represents the

capabilities of an instantaneous water heaters. Such a test would

involve measuring the inlet water temperature, establishing a required

outlet temperature based on a prescribed temperature rise, and

determining the amount of water per minute the water heater could

dispense at the required temperature. (Testimony from February 12,

1997, GAMA at 127-8; EPRI, No. 56 at 8; Oregon, No. 51 at 3; Hawaiian

Electric Co., No. 23 at 2; East Kentucky Power Cooperative, No. 34 at

1.) Nevada Power Company claimed that applying the first hour rating to

instantaneous water heaters ``is inappropriate because consumers may

mistakenly compare instantaneous and storage type water heaters as

being equivalent * * *'' (Nevada Power Co., No. 45 at 4.)

Although all these commenters supported testing for maximum flow

rate, there was some disagreement about temperature rise. GAMA proposed

that the temperature rise should be 77 deg.F, because, assuming an

average inlet water temperature of 58 deg.F, this is consistent with

testing for storage-type water heaters, which are tested at 135 deg.F.

EPRI and the Hawaiian Electric Co. preferred a temperature rise of 50

deg.F for instantaneous water heaters because, they claimed, it

reflects the water temperature that people use. (GAMA, No. 35 at 2,

Testimony from July 21, 1995, GAMA at 11; Testimony from July 21, 1995,

GAMA at 127, 138; Hawaiian Electric Co., No. 23 at 2; EPRI, No. 56 at

8.)

Based on the comments, DOE believes that the current first-hour

rating for instantaneous water heaters may mislead consumers because

those instantaneous water heaters with larger heat input rates can only

provide about

[[Page 58924]]

one gallon per minute at a 77 deg.F temperature rise versus the three

gallons per minute DOE requires from storage-type water heaters in its

first hour rating. DOE agrees with GAMA, EEI, EPRI, and other

commenters that a test for a maximum flow rate (gal/min.) over a

specific temperature rise (77 deg.F or 50 deg.F) is a better way to

compare instantaneous water heaters than a test that determines the

total volume flow over one hour. The heat input rate in BTU per hour or

kilowatts and a specific temperature rise will determine the maximum

flow rate in gallons per minute. The maximum flow rate measures the

ability of instantaneous water heaters to deliver the largest possible

amount of hot water to the user at a specific temperature rise

occurring at any single moment.

DOE agrees with GAMA that the temperature rise should be 77 deg.F.

DOE believes this temperature rise is required to ensure that the

instantaneous water heater can deliver water at 135 deg.F for

dishwashers and laundry or can provide hot water at a minimum

acceptable temperature in places like Maine or Michigan, where the

source water temperature may be much lower than the 58 deg.F used in

the test procedure.

Based on the above reasons, the Department proposes to revise the

test for rating of instantaneous water heaters from the first hour

rating to the maximum flow rate in gallons per minute (gpm) at a 77

deg.F temperature rise. This temperature rise will ensure consumers

that instantaneous water heaters can provide hot water for laundry and

dishwasher use and can dispense water at an acceptable temperature in

cold regions of the country. DOE proposes to call this rating criterion

the maximum gpm rating.

The Department proposes to insert the following text at the

appropriate sections in the proposed test procedure:

1.9 Maximum GPM (LPM) Rating means the maximum gallons per minute

(liters per minute) of hot water that can be supplied by an

instantaneous water heater while maintaining a nominal temperature rise

of 77 deg.F (42.8 deg.C) during steady state operation at its maximum

rate of input energy.

5.2.3 Maximum GPM (LPM) Rating Test for Instantaneous Water

Heaters. Establish normal water heater operation at the maximum input

rate with the discharge water temperature set in accordance with

Section 5.2.1 (procedure for setting the outlet discharge temperature).

During the 10-minute test, with no interruption to the electricity or

fossil fuel supplied to the water heater, either collect the withdrawn

water for later measurement of the total mass removed or,

alternatively, use a water meter to directly measure the volume of

water removed.

Begin with the water flow temporarily discontinued. Record the

scale or water meter reading as appropriate. Turn on the hot water and

record the corresponding time. Record the inlet and outlet water

temperatures beginning 15 seconds after the hot water is turned on and

at every subsequent 5-second interval throughout the duration of the

test. At the end of 10 minutes, turn off the hot water. Determine the

mass of water collected, M10M, in pounds (kilograms), or the

volume of water, V10M, in gallons (liters), with an error no

greater than 2 percent.

6.2.1 Maximum GPM (LPM) Rating Computation. Compute the maximum

gpm (lpm) rating as:

[GRAPHIC] [TIFF OMITTED] TP31OC97.005

Where:

M10m = the mass of water collected during the 10-minute

test, lb (kg).

Tdel = the average delivery temperature, deg.F ( deg.C).

Tin = the average inlet temperature, deg.F ( deg.C).

= the density of water at the average delivery temperature,

lb/gal (kg/L).

If a water meter is used in lieu of a scale, the maximum gpm

(liter/min) rating is computed as:

[GRAPHIC] [TIFF OMITTED] TP31OC97.006

Where:

V10m = the volume of water measured during the 10-minute

test, gal (L).

Tdel = the average delivery temperature, deg.F ( deg.C).

Tin = the average inlet temperature, deg.F ( deg.C).

B. Heat Pump Water Heater Storage Tanks

In the NOPR, DOE proposed a definition for a heat pump water heater

storage tank: ``Heat Pump Water Heater Storage Tank'' is an insulated

tank designed, wired, and labeled for use exclusively with an add-on

heat pump water heater or solar water heater and being unable to

operate without an add-on heat pump water heater or solar water heater.

The heat pump water heater storage tank may contain one or two

thermostats and up to two electric resistance heating elements, and has

a manufacturer's rated capacity of 120 gallons (450 liters) or less.

When tested with the add-on heat pump water heater or solar water

heater inoperative, the heat pump water heater storage tank shall have

an energy factor that is determined in accordance with the test

procedure for water heaters.

GAMA objected to the Department's proposed definition for a heat

pump water heater storage tank. GAMA also proposed that a 50-gallon

tank that meets the minimum DOE energy factor is adequate for testing

any add-on heat pump water heater sold without a tank by the

manufacturer. (Section 4.9.3 of the existing DOE test procedure

specifies a 471 gallon tank with an Energy Factor of

0.87.01.) Supporters for GAMA's proposal included EPRI, the

Oregon Energy Office, and Virginia Power. The Oregon Energy Office

suggested that DOE review the definition in the current test procedure.

(Testimony from February 12, 1997, GAMA at 229, EPRI at 227; Oregon,

No. 51 at 6; Virginia Power, No. 50 at 4.)

Based on the above comments, the Department is proposing to delete

its proposed definition for a heat pump water heater storage tank. The

Department is revising the current installation requirement in Section

4.9.3 for a heat pump water heater storage tank. The Department

proposes to insert the following text at the appropriate section in the

proposed test procedure:

4.10 Heat Pump Water Heater Storage Tank. The heat pump water

heater storage tank to be used for testing a heat pump water heater

without a tank supplied by the manufacturer shall be an electric

storage-type water heater. The electric water heater shall have the

following specifications: a volume of 47.0 gallons 1.0

gallon (178.0 liters 3.8 liters); two 4.5 kW heating

elements controlled in such a manner as to prevent both elements from

operating simultaneously; and an Energy Factor greater than or equal to

the minimum energy conservation standard (as determined in accordance

with Section 6.1.7) and less than or equal to the sum of the minimum

energy conservation standard and 0.02.

C. Heat Pump Water Heater

In the NOPR, DOE proposed to amend the definition of Heat Pump

Water

[[Page 58925]]

Heater with the following definitions of internal heat pump water

heater and add-on heat pump water heater.

1.11.3.a. Integral heat pump water heater An air-to-water heat pump

integral with an insulated storage tank.

1.11.3.b. Add-on heat pump water heater An air-to-water heat pump

designed for use with a heat pump water heater storage tank.

EEI and EPRI claimed the definition for add-on heat pump water

heater is inappropriate and should not be adopted. They stated that

add-on heat pump water heaters are designed to work with any electric

water heater tank and that some are designed to work with any tank.

EPRI further stated that there are no storage tanks labeled and

designed for use exclusively with heat pump water heaters. Therefore,

EPRI believed the new definition would not allow testing of add-on heat

pump water heaters because no heat pump water heater tanks are labeled

for use exclusively with heat pump water heater storage tanks. EPRI

claimed this new definition would increase costs of tanks used with

heat pump water heaters because these tanks must be specialty tanks.

Further, EEI claimed that this definition ``is ill-advised; at best, it

is likely to create confusion and increase the cost of heat pump water

heaters.'' (Testimony from July 12, 1995, EEI at 29; EEI, No. 2 at 7;

EEI, No. 27 at 7; EPRI, No. 17 at 5.) Vaughn Manufacturing Corp.

stated, ``Now DOE is proposing to add more than one category of heat

pump water heaters and a solar water heater. These new units will add

to the confusion unless care is taken to see that the criteria are

applied to comparative models on a valid basis.'' (Vaughn, No. 31 at

4.)

GAMA objected to the definition of ``integral heat pump water

heater'' because the definition implies that the heat pump is

structurally integrated with a tank, whereas, in reality, the heat pump

and the tank can be physically separated, but are usually sold by the

manufacturer as a packaged unit. GAMA suggested that instead of the

1995 DOE proposed definitions of ``integral heat pump water heaters''

and ``add-on heat pump water heaters,'' the respective definitions

should be ``heat pump water heaters with tanks'' and ``heat pump water

heaters without tanks.'' (Testimony from February 12, 1997, GAMA at

229-31.)

The Department finds that the definition of ``integral heat pump

water heaters'' should be withdrawn as commenters GAMA, EPRI, Oregon

Energy Office, and Virginia Power suggested. In place of the definition

of ``integral heat pump water heaters,'' the Department proposes the

following definition: Heat pump water heater with storage tank means an

air-to-water heat pump sold by the manufacturer with an insulated

storage tank as a packaged unit. The tank and heat pump can be an

integral unit or they can be separated.

The Department is also withdrawing the definition for an add-on

heat pump water heater and proposes the following definition.

Heat pump water heater without storage tank (also called add-on

heat pump water heater) means an air-to-water heat pump designed for

use with a storage-type water heater or a storage tank that is not

specified or supplied by the manufacturer.

The Department welcomes comments on these three topics.

Issued in Washington, DC, on October 24, 1997.

Joseph J. Romm,

Acting Assistant Secretary, Energy Efficiency and Renewable Energy.

[FR Doc. 97-28908 Filed 10-30-97; 8:45 am]

BILLING CODE 6450-01-P