Sensors This temperature controller works with almost imperceptible noise making it a smart choice for DIY. Direct use for industrial cooling systems and temperature control. A temperature controller is a device used to control temperature and is commonly used in various heating and cooling processes such as air conditioners and refrigerators. Its main function is to control the operating status of the heating or cooling equipment by measuring the temperature and comparing it with the set temperature to maintain a stable temperature. Temperature controllers are usually composed of several components such as temperature sensors comparators and actuators. The temperature sensor is used to detect the temperature compare the temperature data obtained with the set temperature and decide whether to open or close the actuator based on the comparison result. Actuators on the other hand are used to control the switching of heating or cooling equipment such as relays or inverters. Easy to install standard size and specification can be installed directly or replace the old parts damaged parts convenient and time-saving. Note: To prevent accidents please turn off the equipment before installation.