scope:

This Standard is intended for the performance rating of factory-assembled unitary heat pumps, that are intended for use in direct-expansion (DX) ground-source heat pump systems. 

Within the scope of the Standard, DX heat pumps are classified as single-package or matching assemblies that utilize indoor air as the energy sink on heating and the energy source on cooling, and a refrigerant as the heat transfer medium to the ground.

This Standard appleis to electrically-driven, mechanical, vapour-compression-type systems charged with one of the refrigerants listed in Group A1 of CSA Standard B52 or ASHRAE Standard 34. (See Appendix C of this Standard).

This Standard covers equipment that has a cooling or heating capacity, up to and including 21.0 kW (72,000 Btu/h) at standard rating conditions.

The values given in SI units are the standard. Values given in parentheses are for information only.