How heat pumps warm a home using outside air

A practical guide for Ridents readers, written from everyday experience.

A heat pump works like a refrigerator in reverse. It collects heat from the outside air, the ground or water and moves it indoors using a refrigerant cycle powered by electricity. Because it moves heat rather than generating it by burning fuel, a well-installed system can deliver several units of heat for every unit of electricity it uses, even in cold weather.

A heat pump works like a refrigerator in reverse.

Heat pumps run best at lower temperatures for longer periods, so good insulation and correctly sized radiators or underfloor heating make a large difference. Before deciding, ask an accredited installer for a heat loss survey of the whole house rather than a quick estimate. Check which local grants or incentives apply, since these can change the cost considerably.