Cold-climate heat pump

A cold-climate heat pump is an air-source heat pump certified to keep delivering useful heat at 5 °F (−15 °C); under ENERGY STAR it must keep at least 70% of its 47 °F capacity there at a COP of at least 1.75.

Every air-source heat pump loses heating capacity as the outdoor air gets colder. A cold-climate model has been tested and listed for how much heat it still delivers at low temperatures, not only at the standard 47 °F (8.3 °C) rating point.

In the United States two definitions are in common use. ENERGY STAR’s Cold Climate designation, in Version 6.2 of its specification, requires:

a COP of at least 1.75 at 5 °F;
at least 70% of the 47 °F heating capacity at 5 °F;
a controls verification test at 5 °F;
HSPF2 of at least 8.5 for ductless split systems, or 8.1 for ducted and single-package systems.

The Northeast Energy Efficiency Partnerships (NEEP) keeps its own specification and product list; its Version 4.0 has applied since January 1, 2023.

The label says a unit performs well in the cold. It does not say the unit is the right size for a particular house. That depends on the home’s heat loss at the local design temperature and on the unit’s capacity at that temperature, taken from the manufacturer’s extended performance data.

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