Pt. 430, Subpt. B, App. B
Appendix B to Subpart B of Part 430
—Uniform Test Method for Measuring the Energy Consumption of Freezers
The provisions of appendix B shall apply to all products manufactured on or after the effective date of any amended standards promulgated by DOE pursuant to Section 325(b)(4) of the Energy Policy and Conservation Act of 1975, as amended by the Energy Independence and Security Act of 2007 (to be codified at 42 U.S.C. 6295(b)(4)
Section 3, Definitions,
of HRF-1-2008 (incorporated by reference; see § 430.3
) applies to this test procedure.
1.1“Adjusted total volume” means the product of the freezer volume as defined in HRF-1-2008 (incorporated by reference; see § 430.3
) in cubic feet multiplied by an adjustment factor.
1.2“Anti-sweat heater” means a device incorporated into the design of a freezer to prevent the accumulation of moisture on exterior or interior surfaces of the cabinet.
1.3“Anti-sweat heater switch” means a user-controllable switch or user interface which modifies the activation or control of anti-sweat heaters.
1.4“Automatic defrost” means a system in which the defrost cycle is automatically initiated and terminated, with resumption of normal refrigeration at the conclusion of defrost operation. The system automatically prevents the permanent formation of frost on all refrigerated surfaces. Nominal refrigerated food temperatures are maintained during the operation of the automatic defrost system.
1.5“Automatic icemaker” means a device that can be supplied with water without user intervention, either from a pressurized water supply system or by transfer from a water reservoir, that automatically produces, harvests, and stores ice in a storage bin, with means to automatically interrupt the harvesting operation when the ice storage bin is filled to a pre-determined level.
1.6“Cycle” means the period of 24 hours for which the energy use of a freezer is calculated as though the consumer-activated compartment temperature controls were set to maintain the standardized temperature (see section 3.2
1.7“Cycle type” means the set of test conditions having the calculated effect of operating a freezer for a period of 24 hours with the consumer-activated controls other than the compartment temperature control set to establish various operating characteristics.
1.8“HRF-1-2008” means AHAM Standard HRF-1-2008, Association of Home Appliance Manufacturers, Energy and Internal Volume of Refrigerating Appliances (2008), including Errata to Energy and Internal Volume of Refrigerating Appliances, Correction Sheet issued November 17, 2009. Only sections of HRF-1-2008 (incorporated by reference; see § 430.3
) specifically referenced in this test procedure are part of this test procedure. In cases where there is a conflict, the language of the test procedure in this appendix takes precedence over HRF-1-2008.
1.9“Long-time automatic defrost” means an automatic defrost system where successive defrost cycles are separated by 14 hours or more of compressor operating time.
1.10“Quick freeze” means an optional feature on freezers that is initiated manually. It bypasses the thermostat control and operates continually until the feature is terminated either manually or automatically.
1.11“Separate auxiliary compartment” means a freezer compartment other than the first freezer compartment of a freezer having more than one compartment. Access to a separate auxiliary compartment is through a separate exterior door or doors rather than through the door or doors of another compartment. Separate auxiliary freezer compartments may not be larger than the first freezer compartment.
1.12“Special compartment” means any compartment without doors directly accessible from the exterior, and with separate temperature control that is not convertible from fresh food temperature range to freezer temperature range.
1.13“Stabilization period” means the total period of time during which steady-state conditions are being attained or evaluated.
1.14“Standard cycle” means the cycle type in which the anti-sweat heater switch, when provided, is set in the highest energy-consuming position.
1.15 “Variable defrost control” means an automatic defrost system in which successive defrost cycles are determined by an operating condition variable or variables other than solely compressor operating time. This includes any electrical or mechanical device performing this function. A control scheme that changes the defrost interval from a fixed length to an extended length (without any intermediate steps) is not considered a variable defrost control. A variable defrost control feature should predict the accumulation of frost on the evaporator and react accordingly. Therefore, the times between defrost should vary with different usage patterns and include a continuum of lengths of time between defrosts as inputs vary.
2. Test Conditions
2.1Ambient Temperature. The ambient temperature shall be 90.0 ±1.0 °F (32.2 ±0.6 °C) during the stabilization period and the test period.
2.2Operational Conditions. The freezer shall be installed and its operating conditions maintained in accordance with HRF-1-2008, (incorporated by reference; see § 430.3
), sections 5.3
through section 5.5
.5.5 (but excluding sections 5.5
.5.2 and 188.8.131.52). The quick freeze option shall be switched off except as specified in section 3.1
. Additional clarifications are noted in sections 2.3
2.3Anti-Sweat Heaters. The anti-sweat heater switch is to be on during one test and off during a second test. In the case of an electric freezer with variable anti-sweat heater control, the standard cycle energy use shall be the result of the calculation described in 6.2.2.
2.4The cabinet and its refrigerating mechanism shall be assembled and set up in accordance with the printed consumer instructions supplied with the cabinet. Set-up of the freezer shall not deviate from these instructions, unless explicitly required or allowed by this test procedure. Specific required or allowed deviations from such set-up include the following:
(a) Connection of water lines and installation of water filters are not required;
(b) Clearance requirements from surfaces of the product shall be as described in section 2.6
(c) The electric power supply shall be as described in HRF-1-2008 (incorporated by reference; see § 430.3
) section 5.5
(d) Temperature control settings for testing shall be as described in section 3 of this appendix. Settings for special compartments shall be as described in section 2.5 of this appendix;
(e) The product does not need to be anchored or otherwise secured to prevent tipping during energy testing;
(f) All the product's chutes and throats required for the delivery of ice shall be free of packing, covers, or other blockages that may be fitted for shipping or when the icemaker is not in use; and
(g) Ice storage bins shall be emptied of ice.
For cases in which set-up is not clearly defined by this test procedure, manufacturers must submit a petition for a waiver (see section 7).
2.5Special compartments shall be tested with controls set to provide the coldest temperature. However, for special compartments in which temperature control is achieved using the addition of heat (including resistive electric heating, refrigeration system waste heat, or heat from any other source, but excluding the transfer of air from another part of the interior of the product) for any part of the controllable temperature range of that compartment, the product energy use shall be determined by averaging two sets of tests. The first set of tests shall be conducted with such special compartments at their coldest settings, and the second set of tests shall be conducted with such special compartments at their warmest settings. The requirements for the warmest or coldest temperature settings of this section do not apply to features or functions associated with temperature control (such as quick freeze) that are initiated manually and terminated automatically within 168 hours.
2.6The space between the back of the cabinet and a vertical surface (the test room wall or simulated wall) shall be the minimum distance in accordance with the manufacturer's instructions. However, the clearance shall not be greater than 2 inches (51 mm) from the plane of the cabinet's back panel to the vertical surface. If permanent rear spacers extend further than this distance, the appliance shall be located with the spacers in contact with the vertical surface.
2.7Steady State Condition. Steady-state conditions exist if the temperature measurements taken at 4-minute intervals or less during a stabilization period are not changing at a rate greater than 0.042 °F (0.023 °C) per hour as determined by the applicable condition of A or B described below.
A—The average of the measurements during a 2-hour period if no cycling occurs or during a number of complete repetitive compressor cycles occurring through a period of no less than 2 hours is compared to the average over an equivalent time period with 3 hours elapsing between the two measurement periods.
B—If A above cannot be used, the average of the measurements during a number of complete repetitive compressor cycles occurring through a period of no less than 2 hours and including the last complete cycle before a defrost period (or if no cycling occurs, the average of the measurements during the last 2 hours before a defrost period) are compared to the same averaging period before the following defrost period.
3. Test Control Settings
3.1Model with No User Operable Temperature Control. A test shall be performed during which the compartment temperature and energy use shall be measured. A second test shall be performed with the temperature control electrically short circuited to cause the compressor to run continuously. If the model has the quick freeze option, this option must be used to bypass the temperature control.
3.2Model with User Operable Temperature Control. Testing shall be performed in accordance with one of the following sections using the standardized temperature of 0.0 °F (−17.8 °C).
For the purposes of comparing compartment temperatures with standardized temperatures, as described in sections 3.2
.1 and 3.2.2, the freezer compartment temperature shall be as specified in section 5.1
3.2.1A first test shall be performed with all temperature controls set at their median position midway between their warmest and coldest settings. For mechanical control systems, knob detents shall be mechanically defeated if necessary to attain a median setting. For electronic control systems, the test shall be performed with all compartment temperature controls set at the average of the coldest and warmest settings—if there is no setting equal to this average, the setting closest to the average shall be used. If there are two such settings equally close to the average, the higher of these temperature control settings shall be used. A second test shall be performed with all controls set at either their warmest or their coldest setting (not electrically or mechanically bypassed), whichever is appropriate, to attempt to achieve compartment temperatures measured during the two tests which bound (i.e., one is above and one is below) the standardized temperature. If the compartment temperatures measured during these two tests bound the standardized temperature, then these test results shall be used to determine energy consumption. If the compartment temperature measured with all controls set at their coldest setting is above the standardized temperature, the tested unit fails the test and cannot be rated. If the compartment temperature measured with all controls set at their warmest setting is below the standardized temperature, then the result of this test alone will be used to determine energy consumption. Also see Table 1 below, which summarizes these requirements.
Table 1—Temperature Settings for Freezers
||Energy calculation based on:
||Second Test Only.
||First and Second Tests.
||First and Second Tests.
||No Energy Use Rating.
3.2.2Alternatively, a first test may be performed with all temperature controls set at their warmest setting. If the compartment temperature is below the standardized temperature, then the result of this test alone will be used to determine energy consumption. If this condition is not met, then the unit shall be tested in accordance with section 3.2
4. Test Period
Tests shall be performed by establishing the conditions set forth in section 2 and using the control settings as set forth in section 3 above.
4.1Nonautomatic Defrost. If the model being tested has no automatic defrost system, the test time period shall start after steady-state conditions have been achieved and be no less than 3 hours in duration. During the test period, the compressor motor shall complete two or more whole compressor cycles. (A compressor cycle is a complete “on” and a complete “off” period of the motor.) If no “off” cycling will occur, as determined during the stabilization period, the test period shall be 3 hours. If incomplete cycling occurs (less than two compressor cycles during a 24-hour period), the results of the 24-hour period shall be used.
4.2Automatic Defrost. If the model being tested has an automatic defrost system, the test time period shall start after steady-state conditions have been achieved and be from one point during a defrost period to the same point during the next defrost period. If the model being tested has a long-time automatic defrost system, the alternate provisions of 4.2.1 may be used. If the model being tested has a variable defrost control, the provisions of 4.2.2 shall apply.
4.2.1Long-time Automatic Defrost. If the model being tested has a long-time automatic defrost system, the two-part test described in this section may be used. The first part is a stable period of compressor operation that includes no portions of the defrost cycle, such as precooling or recovery, that is otherwise the same as the test for a unit having no defrost provisions (section 4.1
). The second part is designed to capture the energy consumed during all of the events occurring with the defrost control sequence that are outside of stable operation.
184.108.40.206Cycling Compressor System. For a system with a cycling compressor, the second part of the test starts at the termination of the last regular compressor “on” cycle. The average temperature of the compartment measured from the termination of the previous compressor “on” cycle to the termination of the last regular compressor “on” cycle must be within 0.5 °F (0.3 °C) of the average temperature of the compartment measured for the first part of the test. If any compressor cycles occur prior to the defrost heater being energized that cause the average temperature in the compartment to deviate from the average temperature for the first part of the test by more than 0.5 °F (0.3 °C), these compressor cycles are not considered regular compressor cycles and must be included in the second part of the test. As an example, a “precooling” cycle, which is an extended compressor cycle that lowers the compartment temperature prior to energizing the defrost heater, must be included in the second part of the test. The test period for the second part of the test ends at the termination of the first regular compressor “on” cycle after the compartment temperatures have fully recovered to their stable conditions. The average temperature of the compartment measured from this termination of the first regular compressor “on” cycle until the termination of the next regular compressor “on” cycle must be within 0.5 °F (0.3 °C) of the average temperature of the compartment measured for the first part of the test. See Figure 1.
220.127.116.11Non-cycling Compressor System. For a system with a non-cycling compressor, the second part of the test starts at a time before defrost during stable operation when the compartment temperature is within 0.5 °F (0.3 °C) of the average temperature of the compartment measured for the first part of the test. The second part stops at a time after defrost during stable operation when the compartment temperature is within 0.5 °F (0.3 °C) of the average temperature of the compartment measured for the first part of the test. See Figure 2.
4.2.2Variable Defrost Control. If the model being tested has a variable defrost control system, the test shall consist of the same two parts as the test for long-time automatic defrost (section 4.2
5. Test Measurements
5.1Temperature Measurements. Temperature measurements shall be made at the locations prescribed in Figure 5-2 of HRF-1-2008 (incorporated by reference; see
) and shall be accurate to within ±0.5 °F (0.3 °C).
If the interior arrangements of the cabinet do not conform with those shown in Figure 5.2 of HRF-1-2008, the product may be tested by relocating the temperature sensors from the locations specified in the figures to avoid interference with hardware or components within the cabinet, in which case the specific locations used for the temperature sensors shall be noted in the test data records maintained by the manufacturer in accordance with 10 CFR 429.14
, and the certification report shall indicate that non-standard sensor locations were used.
5.1.1Measured Temperature. The measured temperature is to be the average of all sensor temperature readings taken at a particular point in time. Measurements shall be taken at regular intervals not to exceed 4 minutes.
5.1.2Compartment Temperature. The compartment temperature for each test period shall be an average of the measured temperatures taken during the test period as defined in section 4. For long-time automatic defrost models, compartment temperature shall be that measured in the first part of the test period specified in section 4.2
.1. For models with variable defrost controls, compartment temperatures shall be those measured in the first part of the test period specified in section 4.2
5.1.3Freezer Compartment Temperature. The freezer compartment temperature shall be calculated as:
F is the total number of applicable freezer compartments, which include the first freezer compartment and any number of separate auxiliary freezer compartments;
is the compartment temperature of freezer compartment “i” determined in accordance with section 5.1
VFi is the volume of freezer compartment “i”.
5.2.1Per-Day Energy Consumption. The energy consumption in kilowatt-hours per day for each test period shall be the energy expended during the test period as specified in section 4 adjusted to a 24-hour period. The adjustment shall be determined as follows:
18.104.22.168Nonautomatic and Automatic Defrost Models. The energy consumption in kilowatt-hours per day shall be calculated equivalent to:
ET = (EP × 1440 × K)/T
ET = test cycle energy expended in kilowatt-hours per day;
EP = energy expended in kilowatt-hours during the test period;
T = length of time of the test period in minutes;
1440 = conversion factor to adjust to a 24-hour period in minutes per day; and
K = dimensionless correction factor of 0.7 for chest freezers and 0.85 for upright freezers to adjust for average household usage.
22.214.171.124Long-time Automatic Defrost. If the two-part test method is used, the energy consumption in kilowatt-hours per day shall be calculated equivalent to:
ET = (1440 × K × EP1/T1) (EP2−(EP1 × T2/T1)) × K × (12/CT)
ET, 1440, and K are defined in section 5.2
EP1 = energy expended in kilowatt-hours during the first part of the test;
EP2 = energy expended in kilowatt-hours during the second part of the test;
CT = defrost timer run time or compressor run time between defrosts in hours required to cause it to go through a complete cycle, rounded to the nearest tenth of an hour;
12 = conversion factor to adjust for a 50 percent run time of the compressor in hours per day; and
T1 and T2 = length of time in minutes of the first and second test parts respectively.
126.96.36.199Variable Defrost Control. The energy consumption in kilowatt-hours per day shall be calculated equivalent to:
ET = (1440 × K × EP1/T1) (EP2−(EP1 × T2/T1)) × K × (12/CT),
ET, K, and 1440 are defined in section 5.2
EP1, EP2, T1, T2, and 12 are defined in section 5.2
CT = (CTL × CTM)/(F × (CTM−CTL) CTL)
CTL = least or shortest compressor run time between defrosts in hours rounded to the nearest tenth of an hour (greater than or equal to 6 hours but less than or equal to 12 hours);
CTM = maximum compressor run time between defrosts in hours rounded to the nearest tenth of an hour (greater than CTL but not more than 96 hours);
F = ratio of per day energy consumption in excess of the least energy and the maximum difference in per-day energy consumption and is equal to 0.20.
For variable defrost models with no values for CTL and CTM in the algorithm, the default values of 6 and 96 shall be used, respectively.
5.3Volume Measurements. The total refrigerated volume, VT, shall be measured in accordance with HRF-1-2008, (incorporated by reference; see § 430.3
), section 3.30
and sections 4.2
In the case of freezers with automatic icemakers, the volume occupied by the automatic icemaker, including its ice storage bin, is to be included in the volume measurement.
6. Calculation of Derived Results From Test Measurements
6.1Adjusted Total Volume. The adjusted total volume, VA, for freezers under test shall be defined as:
VA = VT × CF
VA = adjusted total volume in cubic feet;
VT = total refrigerated volume in cubic feet; and
CF = dimensionless correction factor of 1.76.
6.2Average Per-Cycle Energy Consumption
6.2.1The average per-cycle energy consumption for a cycle type is expressed in kilowatt-hours per cycle to the nearest one hundredth (0.01) kilowatt-hour and shall depend on the compartment temperature attainable as shown below.
188.8.131.52If the compartment temperature is always below 0.0 °F (−17.8 °C), the average per-cycle energy consumption shall be equivalent to:
E = ET1 IET
E = total per-cycle energy consumption in kilowatt-hours per day;
ET is defined in 5.2.1;
The number 1 indicates the test period during which the highest compartment temperature is measured; and
IET, expressed in kilowatt-hours per cycle, equals 0.23 for a product with an automatic icemaker and otherwise equals 0 (zero).
184.108.40.206If one of the compartment temperatures measured for a test period is greater than 0.0 °F (17.8 °C), the average per-cycle energy consumption shall be equivalent to:
E = ET1 ((ET2 − ET1) × (0.0 − TF1)/(TF2 − TF1)) IET
E and IET are defined in 220.127.116.11 and ET is defined in 5.2.1;
TF = freezer compartment temperature determined according to 5.1.3 in degrees F;
The numbers 1 and 2 indicate measurements taken during the first and second test period as appropriate; and
0.0 = standardized compartment temperature in degrees F.
6.2.2Variable Anti-Sweat Heater Models. The standard cycle energy consumption of an electric freezer with a variable anti-sweat heater control (Estd), expressed in kilowatt-hours per day, shall be calculated equivalent to:
Estd = E (Correction Factor) where E is determined by 18.104.22.168, or 22.214.171.124, whichever is appropriate, with the anti-sweat heater switch in the “off” position or, for a product without an anti-sweat heater switch, the anti-sweat heater in its lowest energy use state.
Correction Factor = (Anti-sweat Heater Power × System-loss Factor) × (24 hrs/1 day) × (1 kW/1000 W)
Anti-sweat Heater Power = 0.034 * (Heater Watts at 5%RH)
0.211 * (Heater Watts at 15%RH)
0.204 * (Heater Watts at 25%RH)
0.166 * (Heater Watts at 35%RH)
0.126 * (Heater Watts at 45%RH)
0.119 * (Heater Watts at 55%RH)
0.069 * (Heater Watts at 65%RH)
0.047 * (Heater Watts at 75%RH)
0.008 * (Heater Watts at 85%RH)
0.015 * (Heater Watts at 95%RH)
Heater Watts at a specific relative humidity = the nominal watts used by all heaters at that specific relative humidity, 72 °F ambient (22.2 °C), and DOE reference freezer (FZ) average temperature of 0 °F (−17.8 °C).
System-loss Factor = 1.3
7. Test Procedure Waivers
To the extent that the procedures contained in this appendix do not provide a means for determining the energy consumption of a freezer, a manufacturer must obtain a waiver under 10 CFR 430.27
to establish an acceptable test procedure for each such product. Such instances could, for example, include situations where the test set-up for a particular freezer basic model is not clearly defined by the provisions of section 2. For details regarding the criteria and procedures for obtaining a waiver, please refer to 10 CFR 430.27