Filter keeps filling with air

[Nick Webster]

So I have a 21 ft above ground pool that I installed last year. Last year everything was working great. I winterized the pool and got it all ready this spring, but the only problem is the large sand filter keeps getting air inside. I have trouble getting the pump to fill the filter up, but even when I do once it runs a while it ends up filled with air. When I turn off the pump all the air rushes back through the pump and out the skimmer and bubbles quite aggressively for a couple seconds. Any thoughts on what the issue may be? (when it is running it seems to be running fine with the proper pressure and circulation)

Thanks

 

[Texas Splash]

Welcome to TFP! Sounds like you have an air leak somewhere. Air leaks are tricky because you may not see water squirting out where air can actually get pulled in. Lack of full prime (pump pot) would indicate a suction side air leak, but I would look everywhere since you also have water going backwards when the pump is off. Places like the filter pressure gauge, pump O-ring & drain plugs (not lubed), 3-way valves, union fitting, etc are all suspect for allowing air into the system.

 

[Texas Splash]

Also, since this is an AGP, if you use flex hoses those and their connections are quite prone to letting air in. Check those carefully if it applies to your set-up.

 

[Nick Webster]

Also, since this is an AGP, if you use flex hoses those and their connections are quite prone to letting air in. Check those carefully if it applies to your set-up.

I'm a bit new to pool maintenance, are flex hoses to really rigid hoses typically ran from the pump to the filter? Also all of the same equipment was used last year and worked just fine. And the only water that moves backwards after shutting the pump off is what is in the line, it is mostly air that is forced backwards and bubbles like a geyser out of the skimmer, mixing around all the the particulates that were in the skimmer basket.

 

[Texas Splash]

It might help for you to post a couple pics of your pool and equipment pad so we can see everything. Also, be on the lookout for a PM.

 

[Nick Webster]

It might help for you to post a couple pics of your pool and equipment pad so we can see everything. Also, be on the lookout for a PM.

 

[Texas Splash]

I would definitely check those black hoses and where they connect from the skimmer to the pump and suction port. They are notorious for getting a tiny crack or letting air in somewhere. If the equipment was out last winter it could've resulted in a defect somewhere.

 

[tstex]

you can crank up your system and spray a soap/water combo to produce small bubbles. If there's a suction leak, you'll see that those bubble disappear and possibly a sucking sound, depending on the size of an expected leak.

As stated, going back to any and all things you tightened up this spring for pool season 2, if you did not add silicone to o-rings and similar, go back and do it again w silicone.

 

[MITBeta]

Did you lubricate the pump o-ring?