You can also place the SpeedComfort at the top of the radiator. However, the best results are achieved by placing the SpeedComfort under the radiator, as the cooler air is drawn in from below, transported through the radiator, and blown into the room warm. Additionally, most people choose to place the SpeedComfort under the radiator because the fans are less audible and visible there. After all, both the eye and the ear deserve some consideration!