Installation
- Close the upstream shut‑off valve and open a downstream fixture to relieve line pressure.
- Remove the relief valve cover screws and lift off the cover.
- Take out the diaphragm, plunger, spring, and seat components from the pressure vessel.
- Inspect the housing for damage or corrosion; clean surfaces as needed.
- Install the new RK1‑375V kit components in the correct order: relief valve seat, spring, diaphragm, plunger, and o‑rings.
- Apply silicone grease to all o‑rings before installation to ensure proper sealing.
- Reattach the relief valve cover with the provided screws, tightening evenly.
- Slowly reopen the upstream shut‑off valve, purge air, and check for leaks.
- Confirm proper operation by observing relief valve discharge and outlet pressure stability.
- For detailed steps, refer to the repair kit manual or contact a licensed plumber.
Maintenance
- Inspect the backflow preventer annually for leaks, pressure creep, or relief valve discharge issues.
- Clean or replace rubber components if debris or wear is observed.
- Test outlet pressure with a downstream gauge to verify correct performance.
- Replace the RK1‑375V kit if diaphragm, seat, or o‑rings show cuts, tears, or deterioration.
- Ensure test cocks are functional and caps are secure.
- For service or repairs, consult the manual.