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Watts

Watts RK957 backflow preventer repair kit 21

SKU CH-HWH9-WXQ95 MPN RK957

Repair kit restores 957-series backflow preventers with diaphragm, O-ring and piston assembly

  • TypeDrain Components
  • ColorTransparent
  • Repair kit restores backflow preventer function
  • Includes diaphragm, O-ring and piston assembly
  • Compatible with 957-OSY 3 in and 4 in models
  • New Watts RK957 kit for reliable drainage maintenance

Repair kit for 957-OSY backflow preventers

This Watts RK957 kit supplies the internal components needed to service 957-OSY backflow preventers in the sizes listed by the manufacturer. It contains a diaphragm, an inlet coupler O-ring and a piston assembly for reassembly. The parts are designed for direct fit during routine maintenance or after inspection. Plumbers and facility technicians use it to restore proper function without replacing the whole valve.

Transparent components for visual inspection

The transparent colour lets you verify seating and condition of the diaphragm, O-ring and piston during assembly. No moving mechanical joints or electrical parts are included, so operational noise and power draw are not applicable. Thermal performance depends on the host valve and system pressure rather than the kit itself. The parts install with standard hand tools and require no external energy source.

Highlights

  • Repair kit restores backflow preventer function
  • Includes diaphragm, O-ring and piston assembly
  • Compatible with 957-OSY 3 in and 4 in models
  • New Watts RK957 kit for reliable drainage maintenance

Specifications

TypeDrain Components
ColorTransparent
BrandWatts
ModelRK957

Questions about this item

How is the Watts RK957 backflow preventer repair kit installed, and what step is commonly missed?

The kit installs by replacing the diaphragm, inlet coupler O-ring, and piston assembly in compatible 957-OSY valves; the step often missed is lubricating the new O-ring with approved grease before seating it to prevent leaks.

What maintenance or replacement will the Watts RK957 backflow preventer repair kit need later?

The rubber diaphragm and O-ring will degrade over time and require periodic replacement; the piston assembly should be inspected annually for wear or mineral buildup during routine backflow testing.

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