heater; heating unit
Refers to a device or appliance used for heating a room or space. Common in product descriptions and everyday conversation.
It was cold, so I turned on the heater.
This heater is energy-efficient.
warm air heater
Standard kanji spelling for a heating appliance or unit.
Variant kanji spelling; 器 is also used for appliances, but 暖房機 is more common.
Compound of 暖房 (heating) and 機 (machine, device).