Low pressure and bubbles in return


New member
May 23, 2007
Hello everyone, I am having a problem with my pump/filter. I'm getting a lot of air in the system, there's bubbles coming from the returns and there's also a couple inches of air in the pump strainer pot. I have checked the o-ring and lubed it, last night I got a can of shaving cream & sprayed it around everything going up to the pump. I didn't really see any areas that looked like they were leaking air. I also raised the water level in the pool a bit since it was a little low, but that didn't seem to help either. The pressure on the gauge is only running at about 5psi until the filter gets pretty dirty and then it will go up to 10-15.

Oh and I have a 20,000 gallon in-ground vinyl liner with a sand filter. Nothing has been changed on the plumbing recently either. If you have any other thoughts of things for me to check please let me know!



TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
As you appear to have already realized, there must be a leak on the intake side that is letting air in. It sounds like you already know the steps to take. Did you remember to take a look at the skimmer to see if there is a vortex that is drawing air down? That sometimes happens when the water is low, but then you said your raised the water level, so that probably isn't it.

Some of these can be quite frustrating. If there is a crack in the pipe between the skimmer and the pump while the pipe is underground there is no simple way to locate it.

If you have more than one skimmer, or a skimmer and a main drain, and valves to control which one is in use, you should try closing one of those valves at a time to see if you can isolate which source has the leak.


LifeTime Supporter
May 26, 2007
The next post is a similar problem which I replied to. Reading yours jogged my memory a little. I got so desparate that I made an air fitting on a union and put in in each line to check especially for underground problems. Plugged up as if for winter and 2 out of 3 lines wouldn't hold air took a shovel to find 2 leaks. Hope you don't need to shovel.


LifeTime Supporter
May 27, 2007
Fayetteville, Arkansas
I had a similar situation last year - drove me nuts. I found a very small pebble or piece of one stuck to the o-ring on the pump pot that allowed for air seepage. But, if you've lubed the o-ring, maybe that's not it.
I would also check the winterizing drain/freeze plugs on the pump pot and impeller areas if yours is equipped with those. There is a chance that one may be cross- threaded.
Hope you find it - good luck.


New member
May 23, 2007
Thanks everyone - I only have one skimmer and no main drain so there's not anything I can close off in order to check certain sections of pipes. But I'm going to go back and double check everything on the suction side above ground as suggested & see what I come up with. I'm hoping I won't have to get out a shovel either!!
I had the a similar problem too. Where the pump was not coming up to prime. Lots of air. So, during a particluarly dry spell I noticed a wet area of ground close to where the hose comes out of the ground and then goes to the pump. I dug about a foot to the hose and there was a fitting! Hose clamps and all that. They where very loose. I couldn't believe the installers had buried a fitting!
Thats how I found the leak. Hope yours isn't too difficult to find.
good luck