E · Glossary
Emitter
An emitter is the part of a heating system that releases heat into a room, such as a radiator, fan convector or underfloor heating loop.
In home heat pump documents, an emitter usually means the heat emitter that transfers heat from the heating system into a room. Common examples include radiators, fan convectors, fan coils, skirting heating and underfloor heating. The term matters because the heat output from each room's emitters affects the flow temperature a heat pump must deliver, and lower suitable emitter temperatures generally help heat pumps operate more efficiently. It is not the heat pump, the heat loss calculation, the heating control or proof that a room will be warm under every operating condition.
Category
Heat pumps and heating
Applies to
Heat pumps & AC
Last reviewed
03 Jun 2026