Draft Details

0.1 Applicability

This Standard describes the test procedures, test set-ups, and calculations required to determine the performance, capacities, energy consumption, and overall efficiency of compressor-cycle air-to-water heat pumps designed to be used as combination space-conditioning and potable water-heating systems “herein referred to as “combination heat pumps”.

0.2 Background

In this Standard the performance of a combination heat pump is characterized by a set of thermal performance descriptors that provide seasonal efficiency ratings for space heating, water heating, and space cooling in a range of climates.

0.3 Application

This Standard applies to packaged and split combination air-to-water heat pump systems and combination designs/configurations with heating capacities up to and including 19 kW (65 000 Btu/h) of total heating capacity at outdoor temperature of -8.3 °C (17 °F) and outlet water temperature of 45 °C (113 °F).

0.4 Inclusions

This standard applies to the following categories of combination air-to-water heat pump systems:

(a) Systems with a built-in buffer tank for heated water storage, or with a factory-supplied buffer tank that is part of the rated assembly

(b) Systems without a built-in or factory-supplied buffer tank; and

(c) Systems may be split, monobloc, or indoor-mounted single-package systems with ducted outdoor air

0.5 Exclusions

This standard does not apply to:

(a)   solar-based or solar-assisted combination systems;

(b)   systems that include a heat recovery function;

(c)   consumer heat pump water heaters;

(d)   pool heaters; and

(e)   chillers.

0.6 Terminology

In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the Standard.

Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.

Notes to tables and figures are considered part of the table or figure and may be written as requirements.

Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.

0.7 Units of measure

The values given in SI units are the units of record for the purposes of this Standard. The values given in parentheses are for information and comparison only. All references to gallons (gal) are U.S. gallons.