Hayward S244T Sand Filter pressure/leak issue

[68ponyman]

I have an issue with my sand filter. When I stop the pump to clear the basket or backwash on occasion it will start to pour water out the pressure release points at the top of the filter. (see pic)


Sometimes it will seal up and not leak but other times it seems to build up pressure and leak. I try letting air into the basket, openning sand filter drain, backwash, go to waste etc. Lately I've been putting it into recirculate and bypassing the filter. If I leave it that way for a few hours I can usually move it back to filter and it will flow without leaking. Sometimes when I turn the pump off when it's leaking I get a back flush of water into the skimmer boxes.

I purchase a new seal for the top of the sand filter (it's about 2 years old) but haven't torn into the piping to put it in yet. Guess the other thing could be the sand is full of junk on the top? Live in Iowa with 3-4 month swim season should sand be changed after 2 years?

Any advise on what could be the cause of this? Advise on a resolution?

Thanks

 

[Richard320]

Welcome!

Sand can get clogged up, but it doesn't wear out. And that's not your problem anyway.

My guess is that you have two problems; they could be one problem with two symptoms, though.

1) You're getting air in the filter and it builds up pressure. When you shut the pump off, the air is no longer compressed and it forces water out. With a top valve, that shouldn't happen. I'd start looking for suction side air leaks. If you use that phrase in the search box, you'll find hundreds of threads about it. Or do you have a slide or something, where there is plumbing above the level of the top of the filter?
2) That seal should be able to hold 50 psi without leaking. If water comes out, it's bad. Or the sealing surface is bad. Or the clamp is loose. Something in that area is causing it to not seal. It's also possible that could be your air leak.

When the pump is running through the filter, coat that leaky area with shaving cream and watch it a while. See if it sucks the foam in anywhere. There's your air leak. The shaving cream will also work on fittings and around the pump basket.

 

[68ponyman]

Well I replaced the O ring on the bottom of the valve and so far my issue seems to be resolved. The O ring did not look damaged, so maybe it just needed to be lubricated and re-seated or something?

I did not find any suction side air leaks, but I'm also not seeing any air in my pump basket. The sand looked OK with just a few pine needles on the top. Seemed a little low though. Not sure how you can tell if you need to add sand? I'm pretty sure I put the correct amount in when I replace the filter a couple years ago.

Thanks for your help.