DE Filter creates geiser thru skimmer when turned off q's

[rio002]

I checked all connections, no leaks, none capped off, all hoses are less than 4ft long except the backwash hose of course. No heater or solar accessories. But it seems to be building up the air up from somewhere over time, just can't find where.

[Poconos]

Something is wrong. If you opened the air release for a minute, that sounds like a long time. Did water finally come out? You need to leave it open until that happens. My guess is it has to be the filter bacause if there was trapped air after it, like in an unused return line or something, it (compressed air) would have to move the mass of water in the filter back through the pump and skimmer and I can't imagine getting that much of a blast from the skimmer. A thought, have someone hold their hand over a return jet as you kill the pump and see if you continue to get a flow for a couple seconds after the pump is shut off. Just another data point. Other than these comments, I'm out of ideas for now.
Al

[PatL34]

Something is wrong. If you opened the air release for a minute, that sounds like a long time. Did water finally come out? You need to leave it open until that happens. My guess is it has to be the filter bacause if there was trapped air after it, like in an unused return line or something, it (compressed air) would have to move the mass of water in the filter back through the pump and skimmer and I can't imagine getting that much of a blast from the skimmer. A thought, have someone hold their hand over a return jet as you kill the pump and see if you continue to get a flow for a couple seconds after the pump is shut off. Just another data point. Other than these comments, I'm out of ideas for now.
Al

Seems to me what is not working is the check valve, or lack of it. A check valve should be installed immediately after the pump, and will prevent your "gieser' very quickly.

This could be bad workmanship on the part of the original installer.

Hope this helps.

Pat

[Poconos]

There should be no need for a check valve in a normal system. Granted it would probably solve this specific problem, but there is some issue that is not yet explained.
Al

[rio002]

OK I went back through and tightened all my hose clamps (was surprised I got a 1/2 turn or so out of the ones on the filter-these were tight 3 weeks ago). I let the filter run all day, it was at 25psi tonight, I opened the air valve and let it stay open for about a minute- the whole time water was coming out with some air too. I left it open til my psi dropped to 20, then simultaneously shut off the pump and pushed the control handle down so it was in between gears--this caused only a small belch out of the skimmer, backwash hose and return valve. It sounded like I got a belch from under the control handle though- is that normal when it's in between gears?
Oh, and the return valve does continue to push after the pump is off for about 10 seconds. I really appreciate all your help in tracking this down, I've only had sand filters before, but those only survive so long lol.

[JohnT]

I opened the air valve and let it stay open for about a minute- the whole time water was coming out with some air too.

As long as air is coming out at all, I'd leave the bleed valve open. Only shut it when it's all water.

[Poconos]

Another thought...are you seeing air bubbles in the pump basket after the pump has been running for a while? 15 minutes or so. I wonder if you're sucking air from someplace and therefore can't bleed the filter or when you do it just gets trapped air again. Anything in the line between the pump and filter other than a hose or pipe? Also, I wouldn't change the valve setting while under pressure. You said it has Hayward controls and I assume that means a multi-port valve. The danger you run is when you release pressure with the handle the rush of water and/or air can lift the spider gasket off its seat and you'll probably destroy it. The burp out the waste line and all the other things still point to trapped air in the filter. Again, best I can do for now.
Al