Glossary · Heating, cooling & ventilation

Cold-climate heat pump (ccASHP)

Also called: cold-climate air-source heat pump · ENERGY STAR Cold Climate · cold climate certified

An air-source heat pump built to keep heating efficiently in deep cold, usually verified by ENERGY STAR Cold Climate or the NEEP list.

What it means

Cold-climate models use variable-speed (inverter) compressors and are tested to hold more capacity and efficiency at −15°C (5°F). The main references are ENERGY STAR's Cold Climate designation and the NEEP Cold Climate Air Source Heat Pump Specification and product list, which publishes low-temperature data used for sizing. Rebate programs often require a listed model.

Why it matters in an audit

In heating-dominated climates, a true cold-climate model can carry most or all of the winter load, reducing reliance on expensive auxiliary heat.

Typical numbers

Reference values with their sources. Your auditor’s report gives the figure for your own house.

What	Value	Source
ENERGY STAR Cold Climate (spec 6.2)	COP ≥ 1.75 at 5°F (−15°C); capacity at 5°F ≥ 70% of capacity at 47°F; HSPF2 ≥ 8.5 ductless or ≥ 8.1 ducted and packaged; SEER2 ≥ 15.2	energystar.gov ↗
NEEP ccASHP Specification v4.0 (effective Jan 1, 2023)	COP above 1.75 at 5°F at maximum capacity; variable-capacity compressor; HSPF2 above 7.7 ducted or 8.5 ductless; SEER2 above 15	neep.org ↗
NEEP v5.0 proposal (released July 7, 2026; comments closed Aug 28, 2026)	Would rely on ENERGY STAR Cold Climate certification or CEE Tier 1 Path A instead of NEEP's own thresholds; NEEP's page still lists v5.0 as coming, with no effective date (checked 2026-10-26)	neep.org ↗
NEEP's target climates	IECC climate zone 4 and colder	neep.org ↗

Sources

Learn more here

Heat pump comparison guide →

Related terms

Air-source heat pump (ASHP) A heat pump that takes heat from outdoor air in winter and releases heat outdoors in summer, using an outdoor unit with a fan.
COP (coefficient of performance) Heat delivered divided by electricity used at a given moment; a COP of 3 means three units of heat for each unit of electricity.
HSPF / HSPF2 A heat pump's heating efficiency averaged over a whole heating season; higher is better, and HSPF2 numbers can't be compared directly with older HSPF.
Variable-speed (inverter) compressor A compressor that ramps its speed up and down to match the heating or cooling needed, instead of switching fully on and off.
Balance point The outdoor temperature where something changes: below the thermal balance point a heat pump needs help; below the economic one, fuel is cheaper.
Auxiliary / backup heat A second heat source — electric elements or a furnace — that helps a heat pump in very cold weather or during defrost.
ENERGY STAR The government-backed blue label for products and some homes that beat minimum efficiency standards by meeting stricter criteria.
CEE tiers Efficiency levels set by the Consortium for Energy Efficiency that utilities and programs use to decide which equipment qualifies.
NEEP cold-climate heat pump list A widely used list of cold-climate air-source heat pumps, kept by Northeast Energy Efficiency Partnerships, with tested performance down to 5°F (−15°C).
Seasonal COP A heat pump's average heat output per unit of electricity over a whole heating season, including defrost and backup heat, instead of at one temperature.
Defrost cycle (heat pumps and HRVs) A short, automatic cycle that melts frost off a heat pump's outdoor coil or an HRV's core in freezing weather; it's a normal part of winter operation.
Region IV and Region V (HSPF test climates) The two climates heat pump heating ratings are usually given for: Region IV, like the Midwest, and the colder Region V, like the northern tier of states.

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