Thermostatic Control Valve Element 300 series

The thermostat remains closed until the coolant reaches the opening point. The thermostat then progressively opens as the coolant increases to the optimum operating temperature, increasing the coolant flow to the radiator. Once the optimum operating temperature is reached, the thermostat progressively increases or decreases its opening in response to temperature changes, dynamically balancing the recirculation and coolant flow, to maintain the engine in the optimum temperature range as engine heat output, and ambient temperature change.