The thermostat does not use batteries. It has a on/off switch on the side of the unit, so the fan is either always off, or controlled by the thermostat setting.
It is usually placed in the same room as the heater so it will turn on the fan once that room is warm and the extra heat can be taken to other rooms. Once the temperature drops, because too much heat has been taken or the heater has been turned off, the thermostat will turn off the fan.
The thermostat can be wired one of two ways. To either operate until the room reaches the preset temperature or to operate starting from the preset temperature. We usually recommend the latter, this ensures your room with the heat source gets warm enough before you transfer the heat to other rooms.
The products listed below are compatible accessories for this item: