Reduced Pressure Principle Assembly

Reduced Pressure Detector Assemblies for Fire Protection Lines

A reduced pressure detector assembly does two jobs at once. It's a high-hazard backflow preventer that keeps stagnant fire-system water - and any additives in it - from flowing back into the potable main. And it carries a metered bypass that catches ground leaks and unauthorized taps before they become a problem the water authority calls you about. On most fire service lines two inches and up, code makes the RPDA the required device, not the optional one.

These are built for the abuse of a fire line. Expect an epoxy-coated ductile iron body, stainless steel internals, springs, and sensing line, plus a compact N-pattern layout that drops into tight mechanical rooms and replacement jobs. We stock the names inspectors already approve - Watts, Zurn Wilkins, Febco, Ames, and Apollo/Conbraco - in the sizes that actually get specified, typically 2-1/2 inch through 10 inch, with OS&Y or tamper-switch butterfly valves.

Match the assembly to your fire flow demand and head loss, not just the pipe size, and confirm the local approval list before you order. Every RPDA needs an annual test by a certified tester, so plan the install with test cocks accessible. Comparing devices? See the lower-hazard double-check detector assemblies for fire lines, or browse all backflow preventers to spec the right protection.