Why do pool filter o-rings fail and how do I replace them?
A pool filter has several o-rings — lid, backwash valve, drain plug, unions, pressure gauge — and any one can cause a leak or loss of pressure. Four things kill them: time and sun, chlorine attack, grit build-up, and being pinched or over-tightened during install.
Match the symptom to the o-ring
- Water leaking under the lid when the pump runs — lid o-ring
- Filter loses pressure after 20 minutes — air being sucked in (pump lid or union o-ring)
- Leak from around the multiport valve handle — spider gasket or piston o-ring
- Water pooling under the filter tank — drain plug o-ring
15-minute lid o-ring replacement
Turn pump off. Release pressure via bleed valve. Remove old o-ring. Clean both sealing surfaces. Apply thin film of pool-safe silicone grease to the new o-ring. Roll on evenly. Refit lid hand-tight plus a quarter turn — no spanners. Restart pump and watch for 5 minutes.
GCC Pool Solutions
Unit 4/1 Distribution Avenue, Molendinar QLD 4214
Phone: 07 5564 8177
Email: sales@goldcoastchlorinators.com.au
Monday–Friday 7:00am–4:30pm. Closed Saturday and Sunday.