Backpressure Problem

[MaximI]

I have a Hayward S244T Sand Filter connected to a Hayward 1hp Super Pump which filters a 33,000 gal pool. Both components are only 1 yr old. The sand filter does not have sand in it. I am using a product called Zeobtite for the media. Mainly because it is supposed to filter better and it only takes 1/2 as much in volume to do it.

Upon the initial hook-up and assembly of it all, everything worked fine. Towards the end of the last pool season and now at the beginning of this years season, the filter releases backpressure when the pump is turned off. It did not do this originally!

When the back pressure is released, it blows the skimmer cover out of position. I can release the the remaining pressure by loosening the filter cover screws on the pump basket cover. This also refills the pump chamber.

My filter pressure gauge is fine @ 10-12 lbs and only shows an increase when it's time to backwash.

What is going on here? I would appreciate any advice that I can get to corect this problem.

Thank You.

[Pool Clown]

Check to make sure the air bleed screen INSIDE the filter is free of debris.

[MaximI]

Check to make sure the air bleed screen INSIDE the filter is free of debris.

Thanks. Just where inside the filter is the air bleed screen located? I was unaware that one even existred.

[Pool Clown]

Is this yours?

If so, the internal air bleed must be incorperated into the valve on top. Maybe someone thats more familiar than I can jump in here and enlighten. For some reason, your'e not passing air out of the tank.(I think the air bleed is clogged in the valve). It's collecting and compressing in the tank. And when the pump goes off, the air decompresses and blows out the suction line. You should be able to bleed the air out of the tank then quickly turn off the pump and it shouldn't blow back.

If this has been an ongoing problem, then the blow back is only part of your problem. If you can bleed off the tank, then come back in an hour and you get more air, you're getting air from somewhere.

[AZMermaid]

What is going on here? I would appreciate any advice that I can get to corect this problem.

Thank You.

If the airbleed in filter is A-OK, it may not be the filter at all. If there is no water leaking on the pressure side or return lines (or filter of course), check for a leak on the suction side of the pump (where water goes into the pump) A suction side "leak" will usually pull air into the pump, so you won't usually see water leakage while the system is running, but might notice some water around the pipe to pump as soon as you turn the pump off.