Potential underground leak on suction line

[seanbeck1]

Hi guys, new to this forum. Already learnt quite a lot from reading lots of posts.

I’m a new pool owner in Hamilton, Canada. I attempted to open my pool yesterday but was having serious trouble with the pump not priming. It seemed to be sucking a lot of air. After a few minutes, it would pressurize for a couple of seconds, and then lose suction. It would continue to do this. It would not prime with my filter on backwash, drain or filter.

I checked skimmer basket, the pump basket, the pump o-ring and checked for any leaks above ground and saw nothing. I have a combo skimmer with two pipe connections. One goes down to my main drain and the other goes to the suction side of my pump.

This is when I started to think that I might have a leak underground. I should mention that my pump is at a higher elevation than my skimmer.

To test for a leak, I re-installed my winterizing plug into the suction side of my skimmer box. Then I went over to my pool house (about 30ft away) and disconnected the pipe connecting to the suction side of the pump. I used my garden hose to fill the whole line. Theoretically, am I right in thinking that with my skimmer plugged, I should be able to fill this line and it will remain full if there are no leaks?

Either way, I filled the line - and it did fill, but then I could see the water level dropping. I’m assuming this means I have a leak underground?

 

[Texas Splash]

Welcome to TFP!

I filled the line - and it did fill, but then I could see the water level dropping. I’m assuming this means I have a leak underground?

If you had a good seal (plug) back at the skimmer suction side hole to isolate that entire line, then yes, that would be a reasonable assumption. Filling that pipe back at the pool house and watching the water level (static test), it should hold. If you were to actually pressure test it I would think it would drop rather quickly. The only other thing that I can think of that "might" create add water flow issues (in either direction) is if you had a partial obstruction. Very common this time of year with pools opening. You might try pushing water backwards a few times just for giggles in case an acorn or some other small item in messing with water flow. Otherwise, you may need to call someone to do a pressure test to pinpoint the potential leak or do some underground exploratory surgery.