Filter Backwash Valve Bypass / Leakage
moderate severityoccasionalCall a proPro repair$100–$300LA-area, parts and labor
DIY cost$0–$0parts and supplies
Typical time1.5 hrfor a pro
Difficulty3 / 51 is easiest
What you'll notice
- Water constantly draining from backwash line
- unfiltered water returning to pool during filter mode
- debris in pool
Likely causes
- Damaged spider gasket in multiport valve
- cracked valve rotor
- loose or missing valve spring
How to keep it from coming back
- Inspect valve gasket annually
- clean gasket and rotor during service
- replace gaskets every 2-3 years
Ranges are estimates; see How We Estimate. Affects: DE and sand filter systems.
This is a job for a licensed pro, especially where electrical, gas or structural work is involved. If you're in the LA area, R.D. Pools offers free quotes.
Equipment involved
Maintenance that prevents it
Related costs
- Filter Cartridge Replacement (per cartridge): $100–$300
- Filter Cleaning (professional service): $150–$300
- Robotic Cleaner Maintenance (annual cartridge replacement, repairs): $50–$300