I · Glossary
Indoor unit
Also known as AC head, fan unit
An indoor unit is the part of a split AC or air-to-air heat-pump system that transfers heat to or from room air.
An indoor unit contains an air-to-refrigerant heat exchanger, fan, filters and controls. In cooling mode it also needs a condensate drainage arrangement. Domestic formats include high-wall, floor-console, cassette and concealed ducted units.
Category
Air conditioning
Applies to
Heat pumps & AC
Last reviewed
28 Jul 2026