Leak Help

[chasejs0]

I currently have a leak in my pool that I have been chasing and trying to identify. I have a 33,000gal pool. With the pump running, the pool loses approximately 1" of water in under 48hours. When the pump is off, I only lost about 1/8" to 1/4" in 48 hours. My pool installer thought it may be a leaking gasket and replaced the skimmer face plate and jet plates/fittings. This obviously did not solve the leak. Thinking it was a return jet leak as it was only leaking under pressure, I bypassed the below grade return jets and ran a pipe above ground and plugged the jets and the leak continued at the same rate as before. The bypass was attached at the outlet of the heater. Even when the water drops below the level of the skimmer face plate the pool continues to leak. When i swap the jandy valve to the main drain only the pump has a hard time priming and just pours into the pump without being able to build up pressure. My only guesses is that I have a leak somewhere in my main drain. The only other option I can think is that I have a leak between the pump and heater outlet below my concrete pad for my pool equipment but I have no noticed any significant amounts of water around that area. There are also no visible leaks anywhere around my equipment and I have also checked my waste from my sand filter as well. My next step is to put a hose in the pump inlet to push water back through the main drain to try and clear any blockages that may be causing the loss in pressure when only the main drain is on. I am also planning to fill the pool back to middle of my skimmer and bypass the main drain via the jandy valve to see if that makes any difference.
I just wanted to get anyone's inital thoughts or suggestions on anything I should be doing differently or anything additionally I should be checking.

Thanks in advance for any help!

 

[Texas Splash]

Welcome to TFP! Your description points to more than one possibility, so it's important to be methodical and eliminate one area at a time. You've done quite a bit already, but here are some things I noticed:
- If you are losing more water when the pump is on, that would point to the pressure side. But other than perhaps under the concrete between pump & heater you seemed to rule that out with the bypass test.
- Losing prime when pulling from drain is either a blockage or broken line. I'm sure your drain has a cover, so getting something in there large enough to cause a blockage would seem odd, but you can try pushing water backwards to see if it helps. Also, don't rule out the possibility of a bad hydrostatic valve in the drain which might be causing water loss.
- You might do a dye test around the pool light if you have a niche behind it. That wouldn't result in more water loss with pump on, but still worth checking.

Leak Detection

A number of things can cause leaks in your pool. You can learn tricks for leak detection and how to pinpoint where your pool is losing water.

www.troublefreepool.com

 

[chasejs0]

Thanks for the quick reply. I do have a drain cover and i have tried pushing water back through with a hose and cloth from the pump and didn't notice any changes. I do not have a pool light. The light was removed when the most recent liner was installed due to a bad ground somewhere. Any suggestions on how to make sure I am not losing directly under my equipment pad between the heater and pump?

Thanks!

 

[Texas Splash]

Any suggestions on how to make sure I am not losing directly under my equipment pad between the heater and pump?

Not without disconnecting one end and plugging the other so that you can try and carefully apply some water or air pressure and monitor. As for the drain test, that's probably a long way to try and push water with just the garden hose. Not sure if this would work either, but a pressure bladder like a Drain King might work a little better to get water down there.