Backwash Valve STUCK

[pspercy]

Pentair backwash valve "push-pull", 2" pvc. 3 yrs old.

Plunger well and truly stuck closed. Cannot twist or pull it. Lubricated O-rings at end of last summer. Tried everything, even tried to bump it out with pump (collar unscrewed), doesn't budge. Can twist a few degrees with great effort but afraid I'll break it.

Help

[PoolDoc]

I don't have a good answer. But, if you can access the top of the valve, you might try spraying silicone lube into the valve.

Unfortunately, some of the things people use on O-rings damage them -- Vaseline comes to mind; motor oil will also damage some types of elastomer. Unlike PVC, many O-rings are NOT very chemically resistant, and if you lubed with the wrong material, you may have created the very problem you wished to avoid.