Fan heaters keep you warm by releasing direct heat very quickly thanks to the built-in fan. Fan heaters have metal coils inside and electricity flows through the coils to heat them. When the coils are warm, they begin to heat the air inside the heater. The heater also has a fan that pushes the warm air out of the heater and into the room. Due to their handy size and the carrying handle on many models, the heaters are mobile and can easily be plugged into a wall socket.