Reduced Pressure Preventer Assemblies - Model


Reduced Pressure Zone Check Valve Assembly

Reduced Pressure Zone Backflow Assemblies (RPZ), also known as RPZ backflow preventers, are crucial devices that prevent the reverse flow of clean water, thereby avoiding contamination. They are widely used by municipalities, homes, and commercial buildings to protect against the mixing of contaminated water into clean municipal water supplies. RPZ valves provide dependable protection against back pressure and siphonage, ensuring that water supplies remain free from harmful compounds such as toxic chemicals, hard metals, pesticides, etc. In residential buildings, RPZ devices are typically used with irrigation systems, boiler systems, fire suppression systems, and forced-air furnaces, acting as a safety measure..

Dolor Sit Amet

  • Built to city and municipal specifications
  • Designed for use in fire protection and domestic feed lines
  • Factory pre-assembled and tested
  • Precast concrete pad and insulated/heated enclosure
  • OEM top name components
  • Metered by-pass and OS&Y shut-off available

A typical RPZ Backflow Preventer Assembly consists of two one-way valves that are connected to block the return of water to the supply line. This system operates by ensuring that the fluid entering the downstream supply has a higher pressure than the water in the supply line. To prevent slight backflow leakage, the closure of one valve creates a pressure difference, tightening the valves and effectively sealing the system from backflow.
For a municipal water system, if the pressure in homes exceeds the pressure on the supply side, the two RPZ valves will close to prevent backflow. If either of the check valves develops a leak, the relief valve is designed to open and release water to the outside, ensuring that water cannot return to the supply line.

Due to their design, RPZ backflow preventers are more prone to high volume and pressure loss than double-check systems. Specifiers must take these losses into account when designing drainage systems. Fluctuations in pressure, whether downstream or upstream, will cause the RPZ assembly to discharge small amounts of water periodically.

RPZ backflow preventers must be installed in areas with proper drainage, as a significant volume of water will be released from the relief valve. Therefore, RPZ assemblies should not be placed in areas where the discharge water could cause damage – proper drainage must be considered when installing RPZ valves.

Double Check Valve Assembly (Zurn 375AST)

Dolor Sit Amet

Additional Resources

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