The working principleBy the temperature controller, electric actuators valve actuator and valve of three parts. Thermostat installed on the room interior walls, with the cable connected to the electric actuator, generally use 100 cm long cable connects actuators to the selected control points (thermostat, programmer, timer or other remote devices). Perform for nut connected to the valve. When indoor temperature reaches the temperature of the temperature controller is set, electric actuators are thermistor begins to work, the heating thermal expansion device to close the valve, on the other hand, the indoor temperature is reduced, the thermostat disconnect, actuators, expansion system contraction, open the valve.