Losing a lot of water

May 23, 2012
49
Montreal, Canada
Hi, after a very active 10 days around our pool with out of towners coming and going and many trees around my pool to dirty it up real good, I though I would pass my manual vacume to waste on the filter before performing my backwash. Then performed the backwas only to fine my pump would go from 0 to 18 on the pressure gauge then back down and up again.. Same for the rince cycle..
Figured it was caused by the low water level from the waste vacum so started to refill the pool from the hose.

After about 12 hrs of filling the water level was barely above mid skimmer arrow.. Maybe a 1/4 inch and in about 6 hrs. Without the hose it has dropped close to 3/4". I've looked for punctures and tested one with food coloring but wasn't that.

I have shut the pump off for the night and will see if it has changed in the morning but from everything I am reading here would point to a leak in the piping. The heat pump has always had water around it but discounted that as condensation. It's always done it. Same goes for a leaky O ring on my pump and there doesn't seem to be more water leaking from there than usual.

I thing that I haven't checked but will tomorrow is if water is leaking from the permanent backwash pipe when the pump is operational. Could this very recent trouble be caused by a faulty filter head?

What other things should I be looking for given my total situation?

Thank you very much, will update tomorrow.

Edit: forgot to mention that the day after all this, without much help from the trees, the pool is as filthy as before the waste vac and after every backwash, it seems that we can see traces of debris coming into the pool from the returns.
 
Let us know what you find out about the backwash line. If it's leaking when the pump is in filter that's most likely your problem.

If it's not leaking from the backwash valve then I'd let it leak until it stops and go from there.
 
Hi, I checked my backwash line but it wasn't leaking so I decided to start by Eliminating leaking pump. I replaced my pump seals and confirm that it isn't leaking anymore, did a visual inspection of the lining and it seems fine.

I refilled the pool to a specified level I had previously marked and shut the heat pump to eliminate the possibility of evaporation from it and added more salt.

Overnight (12 hrs) I lost between 3/4 to an inch of water, the equivalent of 750-1000 gallons on a 1600 sq.ft. surface and my salt concentration did not rise which is why I haven't done the bucket on the step.

I have noticed that the pressure gauge that was normally around 22 is now around 18 after changing the pump seal but it may be normal considering the added friction in the pump.

In hindsight, although I turned the heat pump off, I didn't bypass it in case it could be leaking under the slab but no indications that it is.

If my searches today prove fruitless, I'll refill and let it overnight without the pump running again.

Any thoughts?

Would a simple hole in the lining that I can't even find cause such a loss of water?
Where should I be looking?
 
HI again, got the pool raised to a specific mark on the skimmer again, removed the hose and snorkelled around the pool 3 full times inspecting to about 4 ft down as well as entire shallow end floor without success. I tested 3 older patches with food dye but they are in good condition.
by 8 pm it had lowered about a 1/4", I shut the pump and this morning at 8 am ( 12hrs later ) the pool had gone down about a half inch.

I pulled off the shroud around the skimmer cover on the sidewalk to see below the concrete. a bit humid at spots but bone dry at others. Also tested liner below skimmer for lifting but it's on there tight.

When ON, he pump cover is clear, not showing any water swishing around so I guess there's no air entering there? Maybe?
NOt sure how to test the returns or if they even matter since the pump was off all night.

There's still the line from the drain to the skimmer but I can't see how an unused line would start to leak suddenly.

Please help pointing me to the next logical step and correct me if any of my assumptions are wrong.

Thanks

G
 
Yes, the return piping from the filter to the pool.

Plug the return(s) in the pool and run the test again. That will let you know if that's where the leak is. If it doesn't leak with them plugged, then you can start narrowing down the location of the leak.
 

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THank you very much, I'll get on that tonight.
without the returns plugged of course, If I were to let the pool leak to as low as it will go, is it safe to plug a length of hose in the skimmer and bungee it to the ladder to keep it under water and the pump running periodically to not lose the pool?

Could the return problem be at the collar where the screw on eyelet? is?
 
WELL, I've followed all of my visible return piping but no leaks. Thought the earth was a bit humid at one spot but ended up being a downspout leading to a french drain. Dug under the cement slab that the return passes through but ended up with shovels full of dry earth. I haven't checked under the filter cause its too heavy to lift with water and sand. (will the winterize setting empty the filter's water through the return or backwash line? ) I ask because the filter and pump are on a wooden base I made and I drilled multiple holes for air circulation but seeing as that it's sitting on patio tiles, it may be leaking from there into the joints of the tiles.

Other than that, I'll be digging up the lines to follow them from the pad to the pool and hopefully not have to break concrete. (are there alternatives?)

I ran the pump to the point seen in the pics to put my mind at ease that it wasn't the skimmer but seeing at what level the water is at, Is there something I can check at the fittings end? maybe a gasket? The level has been steady here since shutting the pump about 30 hrs ago

I pulled up a few of the caps around the returns but can't see anything below the steel plates.
 

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I got it. It looked suspiciously like a leak at the return fitting but the fact that it stops when the pump stops likley negates that.

YOu have checked your backwash/waste line, correct? Oops, I see you have.
 
It has to be the return plumbing. It's just a matter of finding it. You could pull the faceplates off, but I'd be surprised if that's where your leak is.

Winterizing the filter will drain the water out of it, but not like you think. It drains through a drain plug on the bottom.
 
I'll keep digging. Assuming the bottom of my filter isn't leaking and the whole equipment area is dry, Is this type of problem common? From one day to the next, out of the blue after many years an underground pipe just gives and starts to leak!!

I'll dig the closest return that's mostly grass and only has a 3 ft sidewalk to see but if it isn't that one, I have about 80 ft of concrete that I really can't dig up and don't see how it could have broken, it extends to the steps of the house at one point (see pic)

Could a smaller flexible pipe be inserted inside broken one?
Is that even doable?
 

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No, it is not common at all. A telltale sign might be if your decking has cracked and dropped/settled far enough to move the pipes underneath.

Broken pipes are the least common of leaks and I would ABSOLUTELY rule out everything else before I suspected the pipe. We have given you some common starting points but you will be the best detective because you are on site.

I would call in a pool company before I would start digging up pipes.
 

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