Skimmer Sucks Air

[bluazul]

Hi, all!

My wife and I purchased our house (made in 1962) about a year and a half ago as a foreclosure. The pool has been in pretty good shape, but the pump will suck air occasionally. I recently figured out that I think it's in the skimmer.

When run with no attachments, everything runs fine. When I have the automatic pool vac hose placed directly into the hold at the bottom of the skimmer, everything runs fine. When I use a skimmer plate to vacuum or when I use a Vac-Mate, the system sucks air. Since the Vac-Mate is see-through, I can see bubbles of air coming from the side. Water is not lost, though. It seems like when there is extra pressure on the skimmer, it pulls air through a crack. When I put dye in and the pump runs, it goes straight down the hole, as it should.

Trying to look through the Vac-Mate, I thought I identified roughly where the crack would be. I bought some epoxy putty and put it on the crack (it felt more like a scratch by feeling it, but everything else felt smooth). After letting it cure, I tried again, and the issue persists. I'm wondering if I didn't put enough putty or if I got the wrong spot. Does anyone have any ideas on how else to identify where a crack may be? I don't really want to spend the money to replace a skimmer when it's something (hopefully) small. Or if you have other ideas. Thanks, in advance!

 

[fritz614]

Have you tried running a garden hose over all places that could suck in air? for example, while it is sucking air, run a hose over the pump pot lid, under the lid where it seals, all unions and connections, fittings, etc....., to see if the bubble stop then? Also, not sure where your crack is, but can you run a garden hose from the outside of the skimmer to see if the bubbles stop then? Hold the hose over the area in question for awhile to give the bubbles in the pump time to evacuate.

 

[lungs414]

I had a problem similar to this after I bought a new vacuum hose with a swivel end to stop the twisting while vacuuming. I also saw bubbles and realized it leaked air because the swivel was attached to the plate and not the vacuum head, this caused air to be sucked into the point where the vac hose connected to the cuff. Not sure if you have a swivel hose but something to check.

 

[bluazul]

Thanks for both your responses. I'm confident it's not the pump lid (for one, we just replaced our single speed with a variable speed, and the problem has occurred with both). And I'm confident it's not the vacuum hose (I thought it was at one point). The reason being that no air gets into the pump when nothing is attached to the skimmer or when the vacuum hose is attached to the hole at the bottom of the skimmer.

The only time there's a problem is when there a lid under the water line on the skimmer, increasing pressure in the skimmer area. We first noticed this when we bought the house and tried to vacuum manually; we didn't know what the problem was at that time. Since we've had the automatic vac, it's been fine. The problem re-emerged when I got the Vac-Mate and air was getting into the pump. When I looked more closely through the Vac-Mate (since it has a clear top), I can see air bubbling into the skimmer area. I pull the Vac-Mate off before it fully fills with air so it doesn't get to the pump. I thought the problem was with the Vac-Mate at first, and Pentair replaced it for me, but the problem continues with the new one. So that's why I'm thinking it's a crack in the side of the skimmer itself.