Reduced pressure zone valves are used in applications where backflow into a water supply could cause significant harm.

RPZ valves prevent both back pressure and reverse flow allowing the water to move in only one direction. Reduced pressure is guaranteed by the differential pressure relief valve, between two independent check valves that automatically relieves excess pressure in the chamber and discharges it into a drain. This means RPZ valves can be used to protect category 4 fluids.

RPZ valves shall not be installed in a place or position which is:

  • liable to flooding
  • above electrical equipment
  • liable to mechanical or other damage
  • exposed to freezing

Buildings that require constant water pressure must install two RPZ valves in parallel. This is to ensure that one device will be available to supply the facility while the other is tested or repaired.

Installing Reduced Pressure Valves

  • RPZ valves must be installed, commissioned and maintained in accordance with the Water Supply (Water Fittings) Regulations.
  • The local water company has to be notified in accordance with Regulation 5. Details of the proposed work must be sent to the water company at least ten days before work is due to start.
  • The valve must be fitted horizontally with the Tundish below the valve.
  • There must be a clearance of 300-1500mm from the ground, 50mm between the RPZ and any rear wall or cabinet and 150mm above the valve to be accessible for testing.

Our expert engineers ensure safe water pressures for fire-fighting, high rise buildings, industrial premises, water towers and supply tanks. Any Pressure reducing valve must be serviced annually by a specially accredited WRAS engineer.

To book your annual service or to install a reduced pressure valve in your building contact our team today.

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