Pressure release valve on sand filter

[Miguel W]

I need help with my sand filter. I unscrewed the release valve and when I tried to screw it back in water constantly flowed out of the valve even when I completely screwed in (tightened) the valve. I tried backwashing and rinsing and when I reset the multiport back to the "Filter" function, water continued to pour out of the relief valve even though it was completely closed. See photo below.
Thank you

 

[Miguel W]

I've been looking at replacement pressure relief valve screws for my Pentair TR100 sand filter and it looks like the screw may be missing an "o" ring on the end as new ones come with "o" rings and I don't see an "o" ring on the end of my screw. Plan to find a new "o" ring tomorrow and see if that will solve the problem.

 

[proavia]

Without the O-ring(s), the air relief valve will leak the O-ring provides the seal..
Be sure to put pool lube on the O-ring(s) before reinstalling.

 

[Miguel W]

Thank you proavia-my pressure valve screw was missing its "O" ring. All is working well now.