Joint Appendix JA14 provides the qualification requirements to meet the standards for central heat pump water heater (Central HPWH) systems set forth in Title 24, Part 6, Section 170.2(d)2 and in performance standards set forth in Section 140.1 and 170.1.

Basic Model means, with respect to a central HPWH, all units of a given type of product manufactured by one manufacturer; having the same primary energy source; and, which have essentially identical electrical, physical, and functional (or hydraulic) characteristics that affect energy consumption, energy efficiency, water consumption, or water efficiency.

To qualify as a central HPWH for use for compliance, the central HPWH products shall be certified to the Energy Commission to meet the following requirements:

Manufacturers shall determine central HPWH performance data for each basic model either by testing pursuant to the requirements in (a) or by simulating pursuant to the requirements in (b) below:

1. Testing shall be conducted in accordance with the test setup, installation, calculation procedures, and instruments described in Appendix E to Subpart G of 10 CFR Part 431 for each of the test conditions described in JA14.3.3; or
2. Simulated performance shall be conducted using an alternative efficiency determination methods (AEDM) as described in 10 CFR part 429.70(a)-(c) to generate the performance data described in JA14.3.2. In addition, manufacturers shall only simulate the performance of other central HPWH basic models sharing the same series compressor, same type of heat exchangers, and same architecture as the tested basic model.

The following performance specifications shall be submitted to the Energy Commission:

The performance data shall be provided at the following conditions:

For conditions where defrost strategies operate, reported data shall include at least one complete defrost cycle, or alternatively, for each model submitted for approval, provide a description of the defrost strategy including method, cycle length, and process.

The Central HPWH basic model shall be tested at the following conditions:

The Central HPWH system shall be capable of supplying hot water at design outlet water temperature under specified operating ranges for:

1. Minimum and maximum ambient air temperature;     
2. Minimum and maximum cold-water temperature;    
3. Minimum and maximum building demand at design draw and recovery conditions and duration; and
4. Recirculation loop heat loss.    

Design documentation shall specify the operating conditions at which the primary heat pump water heater can supply hot water at design outlet water temperature without engaging auxiliary heating mechanism.