Finding Suction-Side Leak - next steps

[LKellatl]

Hello, my wife and I purchased our home back in October of last year and inherited the pool the came with it. Its definitely needed some TLC (new liner, new main drain) but we're excited to finally get some use!

While doing the initial startup, I've noticed that there is quite a bit of air being let into the system. The pool is in-ground and has 3 suction inlets: one main drain and 2 skimmers. These 3 pipes come out of the ground about a foot from the pump. They each have an inline valve before they connect to the T to the strainer basket.

If I have only the main drain and one skimmer open, there are no bubbles, but as soon as I add the far skimmer, air is let into the system. I inspected the PVC for the suspect line and could not find any obvious issues. Decided to add some flexible sealing tape around the joints (not threaded) to be safe. The issue still seems to persist, however.

The water level is at least half way up the skimmer and the skimmer does not seem to be creating a vortex or sucking in air.

The system seemed to be properly winterized, but I'm concerned water may have been left in this pipe and cracked it underground.

What would the reasonable next troubleshooting steps be?

Additionally, Can i run off of one skimmer and one main drain for the time being while I troubleshoot this issue? The pump seems perfectly happy with just the 2 inlets. Circulation seems okay, but is obviously diminished.

All help is greatly appreciated! Please let me know if I've left or any important info.

 

[reggiehammond]

I had really good luck using this method.

 

[LKellatl]

I had really good luck using this method.

That's a great tip! I'll give that a try. I've got it narrowed down to one of the two skimmer lines. I'll check the joint seams and valve and see if anything takes in water. None of them seemed leaky upon inspection, but maybe this will reveal something.

Fingers crossed that the issue is above ground!

 

[wgipe]

If you have valves that can be rebuilt, you might take the valve apart and lubricator everything with pool lube. Those can sometimes be the culprit.

 

[LKellatl]

If you have valves that can be rebuilt, you might take the valve apart and lubricator everything with pool lube. Those can sometimes be the culprit.

Would it be likely for the valve to leak while open but not while closed? They don't look serviceable without replacing them completely, unfortunately.

 

[Texas Splash]

You absolutely can run the pool just fine with the drain and one skimmer only. In fact you could run it with just one skimmer only if needed. As for that trouble line (far skimmer), if it utilizes a 3-way valve, you could take it apart and check the O-ring and any other gasket. You can pull air "in" but not see water come out. If everything above ground seems fine, you might have two other options - either a cracked pipe or blockage. If you have a pressure bladder like a Drain King or something, you could try pushing water back & forth on that line to see if something is stuck in there. But if water flows through the line fine, a pressure test might be next to confirm if there's a break.

 

[laprjns]

I had a similar issue, turned out that one of my inline valves had a crack along the length of the valve. The crack was not visible. After playing around, opening and closing my 3-way valve I was able to see a squirt of water coming out of the valve body on the main drain line. I used JB Weld to seal it and now I don't have any problems. I will eventually be getting around to replacing those valves.
I'm sure that the garden hose trick would have helped me solve my problem a lot quicker.