Thermostat, also known as thermostat, is an automatic temperature control device that controls the flow path of coolant. By sensing the temperature of the coolant, it automatically adjusts the amount of water entering the radiator and changes the circulation range of the water to adjust the heat dissipation capacity of the cooling system and ensure that the engine works within the appropriate temperature range. The function of the thermostat is to prevent the engine from overheating or cooling and ensure its stable operation.