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Revision 2.0 – 7/10/12

AHAM Refrigerator, 

Refrigerator-Freezer and 

Freezer Ice Making Energy Test 

Procedure

Revision 2.0 - 7/10/12

Proposed
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PREFACE

The Association of Home Appliance Manufacturers develops standards in accordance with AHAM’s 

“Policy and Procedures Governing Technical Standards” which states:

“AHAM Standards shall be in the best interest, mutually, of consumers who use 

appliances, the industries which provide and service appliances, and other 

interested parties. They shall relate to actual use conditions and be technically 

and scientifically sound. ”

Use or observance of AHAM standards is voluntary.

This standard contains:

Test procedures that may be applied to any brand or model of refrigerator, 

refrigerator-freezer and freezer. Results of tests in accordance with this 

standard may be publicly stated.

Recommended levels of performance which are considered important to 

include but which, necessarily, are recommendations only.

With regard to safety, AHAM recommends that all appliance products -- both major and portable --

manufactured or marketed in the United States be submitted to a Nationally Recognized Testing 

Laboratory (NRTL1

) for inspection and listing in conformance with the safety standards and procedures 

followed by such laboratories. The relevant standards for refrigerator, refrigerator-freezer and freezers 

are UL250 and IEC60335-2-24 latest edition.

AHAM welcomes comments and suggestions regarding this standard. Any standard may be reviewed 

and improved as needed. All standards must be updated or reconfirmed at least every five years. Any 

interested party, at any time, may request a change in an AHAM standard. Such request should be 

addressed to AHAM’s president, and should be accompanied by a statement of reason for the request 

and a suggested alternate proposal.

 1 The Occupational Safety and Health Administration (OSHA) recognizes laboratories that have the necessary 

qualifications to perform safety testing and certification of specific products covered within a scope of recognition as 

Nationally Recognized Testing Laboratories (NRTL).
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Copyright © 20xx by the Association of Home Appliance Manufacturers (AHAM) 

All rights reserved.

The hard copy print version of this document shall be for individual use only.

The electronic file version of this document shall be for storage on one computer for purposes of 

viewing and/or printing one copy for individual use only. 

This document shall not be reproduced in whole or in part by any means, and shall not be transmitted 

electronically or otherwise to a third person without the prior written permission of AHAM.
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TABLE OF CONTENTS

Section Page

1. PURPOSE................................................................................................................4

2. SCOPE ....................................................................................................................4

3. DEFINITIONS ..........................................................................................................4

4. TEST PROCEDURE ................................................................................................5
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1. PURPOSE

This standard establishes uniform, repeatable procedures or standard methods for measuring specified 

product characteristics of refrigerators, refrigerator-freezers and freezers.

The standard methods provide means to compare and evaluate different brands and models of 

refrigerators, refrigerator-freezers and freezers regarding characteristics significant to product use.

The standard methods and the recommended levels of performance are not intended to inhibit 

improvement and innovation in product testing, design or performance.

The purpose of the Test Procedure is to measure the incremental energy to make ice by means of 

one or more automatic ice makers installed in a refrigerator, refrigerator-freezer, or freezer. 

The principles of interpretation stated in 10 CFR 430.23 (a)(10) and 10 CFR 430.23 (b)(7) apply to 

this test procedure.

2. SCOPE

2.1. This standard only applies to refrigerators, refrigerator-freezers and freezers, as defined by 

the Department of Energy 10 CFR 430.2, with one or more automatic icemakers (including 

models equipped with the option to install one or more automatic icemakers).

2.2. This standard includes definitions and methods for testing and evaluating refrigerator, 

refrigerator-freezer and freezer automatic ice making energy consumption.

3. DEFINITIONS

3.1. Automatic Icemaker - A device, connected to a water supply, which automatically produces, 

harvests, and stores ice in a storage bin, with means to automatically interrupt the harvesting 

operation when the bin is filled to a pre-determined amount.

3.2. Harvest - The process of freeing and/or removing ice pieces from an icemaker.

3.3. Compressor Cycle - a compressor cycle is a complete "on" and a complete "off" period of the 

motor. 

3.4. Ice Storage Bin - A container in which ice can be stored.
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4. TEST PROCEDURE – Incremental Ice Making Energy Consumption

4.1. Overview:

4.1.1. The refrigerator is to be set up per the DOE Energy Test (per 4.2.1 and 4.2.2) except 

the controls are to be set to obtain a fresh food temperature of 39 +/- 2 °F and a freezer 

temperature of 0 +/-2 °F. Ice maker mold should be full during stability portion of test.

4.1.2. The DOE Energy Test 10 CFR 430 Subpart B Appendix A targets for, the fresh food 

compartment interpolation a temperature of 39 °F and for the freezer compartment a 

temperature of 0 °F. 10 CFR 430 Subpart B Appendix B targets 0 °F for freezer 

compartment interpolation. This incremental ice making energy test focuses on those

target temperatures in the baseline test to simplify the burden of measuring ice making 

energy.

4.1.3. When the ice maker is enabled for the second portion of the ice making energy test,

the controls are not to be adjusted. The compartment temperatures may move outside 

the target of 39/0 +/- 2 °F due to ice making. This is recognized and accepted since the 

customer is not expected to adjust the control settings for ice making vs. non-ice making.

4.2. References

4.2.1. 10 CFR Part 430, Subpart B, Appendix A: Uniform Test Method for Measuring the 

Energy Consumption of Electric Refrigerator and Electric Refrigerator-Freezers.

4.2.2. 10 CFR Part 430, Subpart B, Appendix B: Uniform Test Method for Measuring the 

Energy Consumption of Freezers.

4.2.3. AHAM HRF-1-2008

4.3. Test Equipment and Conditions

4.3.1. Test setup per DOE Energy Test. 

4.3.2. Inlet Water Temperature – 90 +/-2 °F

4.3.3. Inlet Water Pressure – 60 +/- 15 psig

4.4. Ice Making Incremental Energy Test – Single Ice Maker

Calculate baseline average wattage based on the test results at the control setting that 

achieves the target of 39 +/- 2 °F for the fresh food compartment and 0 +/- 2 °F for the 

freezer compartment with the ice maker on, the ice maker mold is full, harvesting 

disabled, and bin empty. If the product under test cannot simultaneously achieve both 

target temperatures, then the baseline will be conducted at the 0 +/- 2 °F freezer 

temperature.
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4.4.1. Ensure stability has been obtained for the baseline test. For a cycling unit, stability is 

calculated by comparing two periods that each consist of a the fewest number of whole 

compressor cycles exceeding two hours in duration that are separated by the fewest 

number of whole compressor cycles exceeding three hours in duration. In order to be 

considered stable, the temperatures of the two two-hour periods must not differ by more 

than 0.042 °F/hour. For examples of this calculation, see Example 2 and Example 3 in 

the Appendix.

For a non-cycling unit, stability is calculated by comparing two periods of exactly two 

hours separated by exactly three hours. These two two-hour periods must not differ by

more than 0.042 °F/hr. From the middle of the first period to the middle of the second 

period is five hours. The stability criterion is that the two periods’ averages must not 

differ by more than 0.21 °F (5 * 0.042 = 0.21).

Calculate baseline energy, normalized per day, ETBL24 4.4.2. (kWh/day)

ETBL24 = (EPBL ∗ 1440)

TBL

where:

EPBL Baseline energy, energy consumed during the entire stability test period, 

kWh

1440 conversion factor from minutes to days, minutes/day

TBL Baseline time period, time duration of the entire stability test period,

minutes

4.4.3. Initiation of Ice Making Test Procedure

4.4.3.1. For units that can complete the baseline and ice making test without 

encountering a defrost, initiate ice making by enabling the ice maker ensuring that 

water is available, the ice maker mold is full, and that the ice storage bin is empty. 

This would also apply to units where the defrost can be disabled or bypassed by the 

tester. Operate the refrigerator making ice until the ice storage bin becomes full and

stops the ice maker, or the first ice maker harvest after 24 hours have passed from 

the first ice maker harvest, or the next defrost cycle occurs.

4.4.3.2. For units that cannot complete the baseline and ice making test without 

encountering a defrost, initiate ice making after the unit has recovered from a 

defrost per 10 CFR part 430, subpart B, appendix A, section 4.2.1.1 (including 

Figure 1) and 4.2.1.2 (including Figure 2). Operate the refrigerator making ice until 

the ice storage bin becomes full and stops the ice maker, or the first ice maker 

harvest after 24 hours have passed from the first ice maker harvest, or the next 

defrost cycle occurs.
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4.4.4. Incremental Ice Making Energy Calculation: Cycling Unit

The graph below shows a typical watt trace for a refrigerator-freezer with a cycling 

compressor during a period of ice making.

There are two different periods outlined in Figure 1: 1) Following the first full 

compressor cycle, which contains the first ice maker harvest, the ice maker harvest 

cycles time period TIM, (red box), begins at the initiation of the next ice making harvest 

and ends at the initiation of the last ice making harvest, 2) compressor cycles time 

period, Tcomp (green box), begins at the start of the first full compressor cycle after the 

initiation of TIM and ends at the finish of the last full compressor cycle before the ice 

maker harvest cycles time period, TIM (red box), ends.

Watts

Seconds

Ice created after 

the initiation of the 

last ice making 

harvest is not 

included in Mice.

Ice created before 

the completion of 

the first full 

compressor cycle is 

not included in Mice.

Figure 1. Typical Refrigerator-Freezer Watt Trace during Ice Making Period.

The compressor cycles 

time period, Tcomp, ends 

at the finish of last full 

compressor cycle 

before the ice maker 

harvest cycles time 

period, TIM, ends.

The compressor 

cycles time period, 

Tcomp, begins at the 

start of the first full 

compressor cycle 

after the initiation of 

TIM.

The ice maker harvest cycles 

time period, TIM, ends at the 

initiation of the last ice 

making harvest.

Following the first full compressor cycle that occurs 

after the initiation of ice making (see 4.4.3), the 

icemaker harvest cycles time period, TIM, begins at 

the initiation of the next ice making harvest.
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4.4.4.1. Calculate the energy consumed during the compressor cycling during ice 

making (green box) period, normalized to per day, ETcomp24 (kWh/day).

ETcomp24 = EPcomp ∗ 1440

Tcomp

where:

EPcomp energy consumed during compressor cycles time period, kWh

Tcomp compressor cycles time period, minutes

4.4.4.2. Calculate the ice production rate, normalized to per day and adjusted for the 

difference in compressor percent run time between TIM and Tcomp, Ṁ

ice24 (lbm/day)

Ṁ

ice24 = �

Mice

EPIM

� �

EPcomp

Tcomp � (1440)

where:

Mice mass of ice produced during ice maker harvest period, lbm

Note: ice produced during the ice maker harvest cycles time period (red 

box in Figure 1) does not include the following: 

• ice harvested prior to, TIM

• ice harvested after the initiation of the last harvest cycle

EPIM energy consumed during the icemaker harvest cycles time period, kWh

Calculate the incremental ice making energy per unit mass, EMice 4.4.4.3. (kWh/lbm)

EMice = �

ETcomp24 − ETBL24

Ṁ

ice24 �
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4.4.5. Incremental Ice Making Energy Calculation: Non-Cycling Unit

The graph below shows a typical watt trace for a refrigerator-freezer with a non-cycling 

compressor during a period of ice making.

Figure 2. Typical Refrigerator-Freezer Watt Trace for a Non-Cycling Compressor Unit 

during an Ice Making Period.

There is one period outlined in Figure 2: ice maker harvest cycles (red box).

4.4.5.1. Calculate the energy consumed during the ice maker harvest (red box), 

normalized to per day, ETIM24 (kWh/day).

ETIM24 = (EPIM ∗ 1440)

TIM

where:

TIM icemaker harvest cycles time period, minutes

Calculate the ice production rate, Ṁ 4.4.5.2. ice24 (lbm/day)

Ṁ

ice24 = Mice ∗ 1440

TIM

Calculate the incremental ice making energy per unit mass, EMice 4.4.5.3. (kWh/lbm)

EMice = �

ETIM24 − ETBL24

Ṁ

ice24 �

(Minutes)

(Watts)
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4.5. Ice Making Incremental Energy Test – Multiple Ice Makers

4.5.1. Calculate EPBL per 4.4.1 and 4.4.2 with all ice makers on with harvesting disabled and 

the ice maker molds are full.

4.5.2. Initiation of Ice Making Test Procedure

4.5.2.1. For units that can complete the baseline and ice making test without 

encountering a defrost initiate ice making by enabling the ice makers, ensuring that 

water is available, the ice maker molds are full, and that the ice storage bins are 

empty. This would also apply to units where the defrost can be disabled or 

bypassed by the tester. Operate the refrigerator making ice until all bins become 

full, the first ice maker harvest after 24 hours have passed from the first ice maker 

harvest, or the next defrost cycle occurs, whichever occurs first.

4.5.2.2. For units that cannot complete the baseline and ice making test without 

encountering a defrost, initiate ice making after the unit has recovered from a 

defrost per 10 CFR part 430, subpart B, appendix A, section 4.2.1.1 (including 

Figure 1) and 4.2.1.2 (including Figure 2). Operate the refrigerator making ice until 

the ice storage bins become full and stop the harvest, or the first ice maker harvest 

after 24 hours have passed from the first ice maker harvest, or the next defrost cycle 

occurs.

4.5.3. Incremental Ice Making Energy Calculation

Calculate EMice using the procedure laid out in 4.4.4 or 4.4.5 depending on whether the 

unit is cycling.
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1. Appendix

EXAMPLES OF CALCULATIONS INVOLVED IN DETERMINING ICE MAKING ENERGY

1. SCOPE

The data is gathered via a data acquisition system (DAQ) that is capable of capturing timestamps, 

temperatures, watts, and watt-hours. It is preferable for the DAQ to be able to capture events such as 

compressor-on and off events and ice maker harvests. The examples in this Appendix are based on a DAQ that 

captures these events.

2. TEMPERATURES AND STABILITY FOR PART 1

Per 4.1.1 the fresh food temperature is 39 ± 2 °F and the freezer temperature is 0 ± 2 °F prior to the ice making 

portion of the test.

Example 1: The following data is obtained during Part 1 of the test:

Time FF Avg FZ Avg

Cycle 1 8/17/2011 20:23:33 37.60 -2.68

Cycle 2 8/17/2011 22:16:03 37.65 -2.67

Cycle 3 8/18/2011 0:08:32 37.61 -2.66

Cycle 4 8/18/2011 2:00:32 37.53 -2.65

Cycle 5 8/18/2011 3:52:24 37.49 -2.65

Cycle 6 8/18/2011 5:45:06 37.51 -2.66

Cycle 7 8/18/2011 7:37:48

Table 1. Compressor Cycle Times and Compartment Temperatures for Example 1.

The fresh food temperatures meet the 39 ± 2 °F specification; however, the freezer falls outside of the 0 ± 2 °F 

specification. The unit’s controls must be adjusted to meet the specifications before the ice making portion of 

the test begins.

Example 2: The following data is obtained during Part 1 of the test:

Time FF Avg FZ Avg

Cycle 1 8/17/2011 20:23:33 37.60 -1.68

Cycle 2 8/17/2011 22:16:03 38.12 -1.22

Cycle 3 8/18/2011 0:08:32 38.44 -0.98

Cycle 4 8/18/2011 2:00:32 39.01 -0.65

Cycle 5 8/18/2011 3:52:24 39.57 -0.01

Cycle 6 8/18/2011 5:45:06 40.23 0.23

Cycle 7 8/18/2011 7:37:48

Table 2. Compressor Cycle Times and Compartment Temperatures for Example 2.
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The compartment temperatures meet the 39 ± 2 °F and the 0 ± 2 °F specifications. For a cycling unit, stability 

is calculated by comparing two periods that each consist of a whole number of cycles of at least two hours in 

duration that are separated by a whole number of cycles of at least three hours in duration. In order to be 

considered stable, the two periods’ temperatures must not differ by more than 0.042 °F/hour. The cycles’ 

durations are listed below:

Cycle Duration 

(minutes)

Cycle 1 112.5

Cycle 2 112.5

Cycle 3 112.0

Cycle 4 111.9

Cycle 5 112.7

Cycle 6 112.7

Table 3. Compressor Cycle Durations for Example 2.

Cycles 1 and 2 are the first two-hour period. Cycles 3 and 4 are the three-hour period. Cycles 5 and 6 are the 

second two-hour period. The time duration for stability is from the middle of the first period to the middle of 

the second period.

Stability Criterion = 

�

(112.5 + 112.5)

2 + 112.0 + 111.9 + (112.7 + 112.7)2 � minutes

60 min

hr �

× 0.042 °F

hr �

Stability Criterion = 0.31 °F

FF Temperature Difference = |37.76 − 39.90| °F

FF Temperature Difference = 2.14 °F

FZ Temperature Difference = |(−1.45) − (0.11)| °F

FZ Temperature Difference = 1.56 °F

Both compartments’ temperature differences exceed the 0.31 °F stability criterion. Therefore, this unit is not 

stable. It must be allowed to stabilize before the unit begins the ice making portion of the test.
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Example 3: The following data is obtained during Part 1 of the test:

Time FF Avg FZ Avg

Cycle 1 8/17/2011 20:23:33 39.60 -0.68

Cycle 2 8/17/2011 22:16:03 39.65 -0.67

Cycle 3 8/18/2011 0:08:32 39.61 -0.66

Cycle 4 8/18/2011 2:00:32 39.53 -0.65

Cycle 5 8/18/2011 3:52:24 39.49 -0.65

Cycle 6 8/18/2011 5:45:06 39.51 -0.66

Table 4. Compressor Cycle Times and Compartment Temperatures for Example 3.

The compartment temperatures meet the 39 ± 2 °F and the 0 ± 2 °F specifications. Stability is checked per 

Example 2 above.

Stability Criterion = 

�

(112.5 + 112.5)

2 + 112.0 + 111.9 + (112.7 + 112.7)2 � minutes

60 min

hr �

× 0.042 °F

hr �

Stability Criterion = 0.31 °F

FF Temperature Difference = |39.63 − 39.50| °F

FF Temperature Difference = 0.13 °F

FZ Temperature Difference = |(−0.68) − (−0.66)|°F

FZ Temperature Difference = 0.02 °F

Both temperature differences are below the 0.31 °F stability criterion. Part 1 of the test is complete and the 

ice making portion may be initiated.