HPNR Valves

RMC’s High Pressure Expansion Non-Return (HPNR) Valves are a combination non-return and pressure relief device and are suitable for coil type heat exchange water heaters. The non-return prevents the backflow of hot water into the mains supply. The relief valve prevents an over-pressure condition within the coil.

These HPNR Valves limit the maximum pressure in a system by relieving excess pressure to the drain line and are classified as a functional control for this type of application. HPNR Valves should only be installed on the cold or inlet supply of a water heater as the valve is primarily intended to cope with the excess pressure generated during a normal heating cycle.

RMC’s HPNR Valves are available in a 15mm configuration.
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Model Size Product Code
HPNR Unrestricted 15mm HPNR503