SHOP Hot Water System Pressure & Temperature Relief Valve P.T.R
What is a PTR Valves Function?
The Pressure and Temperature Relief valve (PTR) is designed to relieve the increase in pressure caused by water expansion during the normal heating cycle in a hot water tank. The valve will then relieve the increase in pressure by releasing drips of hot water to the drain line. Should the electrical temperature cut-out device that controls the water heating element ceases to operate correctly, the water will overheat. The Pressure & Temperature Relief Valves function is to release the pressure.
The temperature of the water in a pressurised unvented or mains pressure hot water heater cannot exceed 99° C. If the thermostatic controlling the element(s) fail the PTR valve operates.