Suction side leak question

[Lisadmn]

Hi Everyone and thanks for all of the great information.

I believe my pool has a suction side leak that we need to isolate and fix cause the pump is not working as efficiently, etc. here are our symptoms:

1. Bubbles in the return lines and pump basket
2. We are NOT losing an appreciable amount of water
3. Pool vacuum (plugged into skimmer-- we do not have a separate suction line-- losses suction intermittently making it difficult to sweep the pool
4. Pool plumbing is copper underground with PVC above ground. Pool is 40 years old.
5. There is no visible problem with the skimmer itself. It is not cracked or losing water.

I think the leak is in the suction line between the skimmer and the pump. I had a repair guy come out who who was trying to sell me a whole new skimmer and line for a huge amount of money. He stated (without doing any leak detection) that he thought the leak was in the plumbing under the skimmer, which would require the work mentioned above as we'll as some digging and deck repair. If this is indeed the problem, is it possible to repair without completely replacing it all?

Does it make sense that the pipe under the skimmer would be leaking and we are not losing a noticeable amount of water?

Any help or advice you can give me is much appreciated. I would love to have some direction before writing checks. I have not yet had a leak detection company out.

 

[Bama Rambler]

The first thing to do is do as much troubleshooting as you possibly can to determine where it's leaking. The vast majority of the suction side leaks we hear about are above the ground. Start by looking in the skimmer when the pump is running and see if it's creating a vortex sucking in air. Also look at the skimmer weir and make sure it's working freely and not sticking. Then clean and reseal the pump basket o-ring and sealing surfaces. Then remove and reseal the pump drain plugs. If all that doesn't find the problem start running water out of a hose over all the suction side plumbing and fittings above the ground.

Post back what you find from there and we'll go from there.

 

[Lisadmn]

Thanks. We have already done some of this, but not all. What would a vortex of water at the skimmer indicate?

 

[Bama Rambler]

That, that's where air was getting into the system. That's usually caused by the water level being too low or the weir not working correctly, or the skimmer basket is missing.

 

[Pool Clown]

Do you still get the air if you unplug the vac from the skimmer? Skimmer vac hoses can easily double, even triple the suction run back to the pump. Not to mention if you have a partial obstruction in the hose (cavitation).

If that pool is 40 years old and has copper, you may be starting to get little pin holes in the copper pipe from erosion. It may be best to replace the whole run. A customer of mine was reluctant to do this, and just wanted us to repair only the section that were leaking (at the time). Needless to say, the whole line is now PVC at about three times the cost that it would have been had he replaced the whole thing at once. Perhaps having a leak detector come and locate the leak may reveal more than one small leak, however, they are usually kinda pricey for their service.

You can have an air leak (pin hole) in the suction side that won't show much loss of water over night when off, but could almost kill prime on a pump since it doesn't take much air to disrupt prime.

 

[Lisadmn]

Thanks to you all for your help. We did trouble shoot the above ground plumbing and the leak was not there. We figured there was a good chance the leak was close to the equipment, so we hired our trusted handyman to cut the cement and dig down. There was indeed a pinhole leak a few inches under the cement in the soil. He repaired it and all is functioning fine for now. It cost me less to repair the hole than to do the leak detection itself.

I know we got lucky. If we have additional problems in the future we will have to reevaluate then. We have a Pentair intelliflo that we run for many hours at a low speed and a large new filter. The pressure on the system moats of the time is very low, so we are hoping to get a few more years out of our pool plumbing.

Thanks for your help!

Lisa

 

[Bama Rambler]

Glad you found it and got it fixed.