Harvey O Rings, G0933 Top Cap O-rings (Pack of 2)

This pack of two G0933 top cap O-rings from WrekinWater is designed to fit the top cap on Harvey Aquasoft non-electric twin tank water softeners, restoring a watertight seal where the cap meets the tank body.

Signs this seal needs replacing

• Water weeping or dripping from around the top cap of the tank.
• The cap needing to be over-tightened to stop it leaking.
• The old O-ring looking flattened, cracked, or perished once the cap is removed.
• A drop in system pressure after the cap has been undone for servicing.

The G0933 O-ring sits under the top cap and is what keeps the tank sealed under mains pressure. Rubber seals harden and lose their shape over years of contact with water and periodic disturbance during servicing, so even a cap that looks fine can leak once the seal beneath it has perished.

WrekinWater has supplied water softener spares to more than 50,000 customers over 15 years from its base in Bettisfield, Shropshire, and is rated Excellent on Trustpilot, so you can order this pack knowing it is matched to the correct Harvey part.

How to replace it

1. Turn off the water supply to the softener and relieve any residual pressure.
2. Undo and lift off the top cap to expose the old O-ring.
3. Remove the perished O-ring and wipe the sealing groove clean.
4. Lightly grease the new G0933 O-ring with food-safe silicone grease.
5. Fit the new O-ring and refit the top cap, tightening evenly by hand.
6. Restore the water supply and check the cap for leaks before leaving the system running.