Air is getting into my filter

[gilbertpsk]

Hi all. It's been a great pool season so far. So much fun, that I decided to clean the filter by removing the cartridges. After I put it back together, it ran just fine...until the next day. Now, after the filter running for 30 minutes, I have to bleed lots of air out of the filter. There aren't any water leaks that I can tell. Maybe I didn't tighten the band around the filter tight enough? Any ideas on where to start troubleshooting?

16' x 36' IG - ~22K gallons
Vinyl liner (2010)
Filter: Pentair Clean and Clear Plus CCP420 420 Sq Ft (2008)
Pump: 1.5 hp Hayward Super Pump
Heater: Sta-Rite Max-e-therm
Chlorinator: Aqua Collection Turbo Cell

[Poconos]

The filter is on the pressure side of the pump so no air would be coming in on that side. Has to be on the suction side. Most common place to look would be the pump basket lid. This is the most likely place to be disturbed and change. Clean the gasket and lube it with silicone grease. Next common air source could be a low water level and a vortex forming in the skimmer momentarily. If a vortex forms the pump will suck a little air, flow drops, vortex goes away and you may never catch this transient event. Also a sticking weir, either a door type or floater whichever you have. If the air source isn't any of these then the plumbing would be suspect next but it's too coincidental with you cleaning the filter so I doubt it's a plumbing leak. Keep in mind that when you cleaned the filter the flow probably increased so that makes me more suspect of something skimmer related.
Al

[gilbertpsk]

Thanks, Al!

If it is skimmer related, how do I fix it? It's a door that opens and closes.

[gilbertpsk]

I found the leak! It's the pipe going from the pump basket to the filter. Any ideas on how to fix it? I'd like to avoid the plumber, if possible.

https://picasaweb.google.com/lh/photo/4mP008W4X5cHb8Fun7IE1w?feat=directlink

Edit by Poconos: Ignore this...was trying something with the pic.

[Poconos]

Yeah, that's a dribble but I don't understand something. That is the pump output pipe, the pressure side. I can understand the dribble but not sure how air would be getting into the filter. Unless somehow the air is getting in when the pump is off. In any case, you need to Unscrew the pipe adapter from the pump and looks like you'll have to cut the pipe to do this. You can get all the PVC parts at Home Depot, Lowes, etc. It looks like a 1.5" pipe so you'll need some 1.5" pipe, a 1.5" male pipe adapter, Purple Primer, PVC cement and teflon pipe tape. I also recommend getting a coupling you can disconnect in the future. You'll put that in a section of straight pipe right above the pump outlet. Talk to someone at the home center and they can set you up with all the right parts. Once you unscrew it, clean the threads on the pump the best you can. Looks like they used pipe dope when they screwed that one in. Use about 8 turns of teflon tape on the new adapter and screw it in. The nice part about adding that coupling is when you get it all back together and it leaks, loosen the coupling and screw in the adapter a little more.
Hope this helps.
Al

[gilbertpsk]

Maybe the leak that I found isn't the air leak because I'm taking on air while the pump is running...I'll work on fixing this little dribble after the air leak. Thanks for the in-depth explanation on the PVC repair. It doesn't look too bad based on your write-up.

Right now, we are actually at a high water level due to some recent rain, so that rules out the vortex. Maybe it's the seal on the basket - I'll get some silicone grease at the depot and try it out. I'll post after.

[Poconos]

OK. PVC is fun to work with and cheap. Let us know if you find silicone grease at HD. May have to go to a pool store.
Al

[gilbertpsk]

Is there a special kind of grease? I was planning on getting this: http://www.homedepot.com/h_d1/N-5yc1v/R-100187900/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

[gilbertpsk]

I went to the pool store and bought a new rubber gasket. Then I went to the depot and picked up the silicone grease. Unfortunately, after an hour or so, when I checked on the filter, there is still air in the filter. Then I checked with my ears and heard some air. When I turned off the pump, I could actually see some water coming from the seal between the pump basket and the PVC coming from the pool. See photo: https://picasaweb.google.com/lh/photo/CcVd8nn3_xjDOMfzZB65OA?feat=directlink

Instead of replacing the pipe, can I be lazy and just fix the seal that's leaking until the fall (and then I'll fix both leaks)? I read online that standard PVC cement can be used without having to cut out the pipe. Maybe I'll swing by the depot again and find someone there?

[Poconos]

Never tried PVC cement on threads like that however, on the suction side you could smear some silicone seal right on the joint. With the pump running it will be sucked in a little before it cures. That should plug the air leak. You should be able to leave the pump running as long as you want after you smear the stuff as it's a real thick goo. Won't work on the pressure side because there is no strength to prevent the escaping water from popping the silicone right off the joint.
And yes...that silicone grease looks just fine. I should grab some at the local HD as I'm always misplacing my almost empty tube of the stuff.
Al

[gilbertpsk]

Thanks, Al. I'll put that silicone grease on the joint and see what happens. Any special way to apply, or just push in with my fingers?

[Poconos]

I suggested silicone SEAL for the joint. Use the grease for the gaskets and O-rings. The seal is the caulking stuff. Just squish it around with your fingers. It starts to cure in 15 minutes or so.
Al

[gilbertpsk]

I put on a silicone seal (GE Silicone I) and the system has been greatly improved. Unfortunately, there is still some air getting into the filter. Is there a product or something that I can use to put around the joints to find other air leaks?

[Poconos]

I don't know of anything to put around joints for finding leaks but one thing I've used is a stethescope without the diaphram. Use the open ended hose to get right at the joints. Works in tight places and really helps when you're listening for very localized noises.
BTW...I looked at Home Depot for that grease and found two types, one says for ceramic seals also but I have no idea what the difference is in the two types. Got the stuff for ceramic and it seems like the right stuff so we'll see. Price is good too.
Al