Item number: 8721008756295 View all Heatfan products > View more: Central heating boilers > A radiator heats up slowly and cools down gradually. This is a relatively slow process, and the Heatfan speed controller and/or sensor ensures that the fans always blow at the perfect speed. Both are highly accurate modulating sensors placed between the power supply and the Heatfan(s). Therefore, you always need one smart controller or one smart sensor per power supply (plug). The sensors are calibrated and will activate at 25.3°C. They will then modulate the Heatfans to increase their blow speed as the radiator/convector temperature increases. As the radiator/convector temperature cools, the Heatfans will decrease their blow speed until a temperature of 24.9°C is reached. Then, the Heatfans automatically switch off. What are the benefits of the HeatFan? Firstly, you can enjoy faster room heating, and your boiler will fire more frequently, heating water more efficiently for shorter periods. Besides the comfort, this will also mean a slight reduction in gas consumption. Assuming that the current type and quantity of radiators are suitable for heating the room, you can also choose to reduce the output of your radiators by either switching to different types or even removing a radiator, allowing your space to be more tailored to your needs. Savings of 15 to 20%, with peaks of up to 30%, on the amount of gas used for heating your home are realistic expectations. P.S. If you purchase a set of heat fans, either the Sensor or the Speed ​​Controller are already included. Product specifications Item description Article number 8721008756295 Color White Product type Accessories Country of origin Netherlands