Abstract: A thermally actuated valve employs a plunger and bore valve configuration. A thermally expansible wax actuator has an axial length that changes in response to the temperature in a cavity of the valve. At temperatures above a predetermined set point, the actuator produces axial force sufficient to extend the length of the actuator against a return bias and project the plunger and seal into the bore, closing the valve. The plunger defines a pressure relief fluid flow path from the valve cavity to the valve outlet. A pressure relief valve is arranged in the plunger and is responsive to pressure in the valve. The pressure relief valve opens to relieve pressure above a pre-determined level. The thermally actuated valve and the pressure relief valve are coaxial and employ a common outlet.

Abstract: A thermally actuated valve employs a plunger and bore valve configuration. A thermally expansible wax actuator has an axial length that changes in response to the temperature in a cavity of the valve. At temperatures above a predetermined set point, the actuator produces axial force sufficient to extend the length of the actuator against a return bias and project the plunger and seal into the bore, closing the valve. The plunger defines a pressure relief fluid flow path from the valve cavity to the valve outlet. A pressure relief valve is arranged in the plunger and is responsive to pressure in the valve. The pressure relief valve opens to relieve pressure above a pre-determined level. The thermally actuated valve and the pressure relief valve are coaxial and employ a common outlet.