Type Guide

Window heat pumps

A window heat pump is a self-contained unit that both heats and cools — like a window AC that also warms a room. Here is what to know.

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By the HeatPumpWise Editorial Team✓ Reviewed against US DOE & ENERGY STAR guidance
Updated June 2026 · 4 min read · How we research & review

How a window heat pump works

A window heat pump — also sold as a window-unit, window-mounted, or "saddle" heat pump — packs the whole refrigerant cycle into one box that sits in a window or wall sleeve. In summer it cools like a window AC; in winter it reverses to pull heat from outdoor air into the room. Newer inverter models (e.g., saddle-style units) are far quieter and more efficient than older ones, and many heat down into the 20s–low teens °F before switching to electric backup.

Cost, pros and cons

Window heat pumps typically cost $400–$1,200 for the unit, with no installation crew — you mount it yourself. Pros: cheap, DIY, heats and cools one room, no ductwork. Cons: single-room only, less efficient than a mini-split, blocks a window, and limited cold-climate output.

💡 For a permanent, efficient single-room solution, a ductless mini-split outperforms a window unit — but costs more and needs installation.

Who they suit

Great for renters, a single room, an apartment, a home office, or anywhere you cannot install a mini-split. For whole-home heating and cooling, step up to a mini-split or ducted system.

Frequently asked questions

Do window heat pumps work for heating?

Yes — unlike a plain window AC, a window heat pump reverses to heat a room, typically down into the 20s–low teens °F before backup electric heat takes over.

How much does a window heat pump cost?

Usually $400–$1,200 for the unit, with no installation cost since you mount it yourself.

Window heat pump vs mini-split?

A mini-split is quieter, more efficient and better in cold weather, but costs more and needs installation. A window unit is cheaper and DIY but single-room and less efficient.

Related

Educational guide, reviewed against US DOE & ENERGY STAR guidance and updated June 2026. Estimates only — not a substitute for a professional assessment or Manual J load calculation.