The SpeedComfort is supplied with an external thermostat switch. This is also put in place with magnets, near the hot water supply. The SpeedComfort will automatically switch on when the radiator is at 33 degrees close to the thermostat. Switching off is also automatic when the radiator cools down to 25 degrees.
The SpeedComfort has been developed for mounting out of sight, at the bottom of the radiator. But the SpeedComforts will function just as well if they are placed between the panels of the radiator at the top. Radiators often have a grid on the top, under which the SpeedComforts can be hidden from view. Keep in mind, however, that the higher temperature at the top will affect the lifespan of the fans.