Fan heaters and oil-filled radiators: how they work

In short: Fan heaters and oil-filled radiators are electric supplementary heaters that convert electricity directly into heat. A fan heater warms a room quickly with a stream of air, while an oil-filled radiator works slowly but evenly and quietly.

In more detail: Both devices convert almost all of the electricity into heat, yet heating with them is usually expensive compared with central heating or a heat pump. They are therefore best suited to short periods and small rooms.

In detail

• Fan heater: A heating wire or ceramic heating element is heated electrically, and a fan blows the warm air into the room; it warms up quickly, but the device is audible.
• Oil-filled radiator: A heating rod inside warms a special oil that circulates in the sealed fins and gives off heat to the air and as radiation; the oil is not used up.
• Slow heat: An oil-filled radiator takes longer to heat up, but keeps giving off heat for a while after being switched off.
• Thermostat: A built-in thermostat switches the heating on and off to maintain a set temperature; without it, the device runs at full power all the time.
• High power, high costs: Such devices often have a power rating of roughly one to two kilowatts; even a few hours a day can noticeably increase the electricity bill.
• Socket: Because of the high power, plug the device directly into a wall socket if possible and do not daisy-chain extension sockets, as they can overheat.
• Keep clear and do not cover: Keep curtains, furniture, clothing and paper away, and never use the device to dry laundry or cover it; on many models a tip-over switch and overheating protection switch it off automatically.
• Further safety: In the bathroom, only use devices the manufacturer approves for that purpose, do not leave the device running unattended, and never open a damaged oil-filled radiator yourself (thermostat-und-heizungsregelung, infrarotheizung-grundlagen, steckdosen-und-sicherungen-im-haushalt).