RPZ Valves & Backflow Preventers

RPZ Valves & Reduced Pressure Zone Backflow Preventers

Shop RPZ valves and reduced pressure zone backflow preventers for commercial plumbing, water systems, mechanical applications and cross-connection control. MasterBuilder Mercantile carries RPZ backflow prevention assemblies from leading manufacturers including Zurn Wilkins, Watts and Apollo, with a range of connection sizes and configurations available.

An RPZ valve, also known as a reduced pressure zone backflow preventer or reduced pressure principle assembly, uses independently acting check valves together with a relief valve to help protect the upstream water supply from backflow caused by backsiphonage or backpressure.

Shop RPZ Valves

Browse the RPZ valves above by manufacturer, model and connection size. Available assemblies include compact bronze RPZ valves as well as larger commercial backflow prevention assemblies for higher-flow applications.

Popular models include the Zurn Wilkins 975XL and 975XL2 series together with reduced pressure assemblies from Watts and Apollo.

For 1-inch applications, view the Zurn Wilkins 1-975XL 1" RPZ valve, a compact bronze reduced pressure principle assembly with 1" female NPT connections, full-port ball valves and convenient in-line service access.

What Is an RPZ Valve?

An RPZ valve is a testable backflow prevention assembly designed to maintain separation between the upstream water supply and downstream systems where backflow protection is required. The assembly incorporates two check valves and a differential relief valve arranged to create a reduced pressure zone between the checks.

If operating conditions cause the pressure within this zone to rise beyond the intended differential, the relief valve can discharge water to help maintain the required separation between the supply and downstream system.

RPZ Valves for Commercial Water Systems

Reduced pressure zone backflow preventers are used in a wide range of commercial, mechanical, industrial and water-system applications. Selecting the appropriate assembly depends on factors including connection size, required flow rate, working pressure, temperature, installation orientation and the level of backflow protection required for the application.

Because backflow requirements vary by installation and jurisdiction, always confirm that the selected RPZ valve and its approvals are suitable for the intended application before installation.

RPZ Valve Testing & Maintenance

RPZ assemblies are testable backflow prevention devices. Inspection, commissioning and periodic testing may be required according to the applicable water regulations and requirements of the local authority.

For testing and servicing equipment, browse our backflow test kits and testing equipment. Replacement components are also available through our backflow preventer parts and repair kits collection.

RPZ Valves vs Double Check Valves

RPZ valves and double check valve assemblies provide different forms of backflow protection and should not be treated as interchangeable devices. The appropriate assembly depends on the application, the degree of risk and the requirements of the relevant water regulations or authority.

Where a double check assembly is appropriate, browse our double check valve assemblies.

Backflow Prevention Equipment

MasterBuilder Mercantile supplies RPZ valves, backflow preventers, testing equipment and replacement parts through our UK online store. For additional types of backflow prevention equipment, browse our complete backflow preventer collection.