Frustrating pool leak with no progress so far! Please help us!!!

[Rick1]

Hello, all!

I have come here in desperation. I moved into this home almost 2 years ago, and since that day, we have been battling with a fairly significant pool leak. We lose about 1 inch of water a day.

Symptoms:

• Lose 1 inch of water per day.
• Water stops dropping just below the skimmer. It will hold at this level.
• Pool leaks with equipment on and off. Leaks faster when pump is running.

What we have done so far:

• Called 2 leak detection companies.
• Pressure tested all lines (except Spa booster line), everything holds pressure
• Dye tested entire structure multiple times. No active leaks in structure (And remember, water level holds just below skimmer). One company said that there was a leak in the spa as dye would go in the spa booster line. We have venturi inserts that would need to be chipped out in order to pressure test that line. We have repeated dye tests multiple time, with no signs of an active leak. Dye no longer goes in the line so we have put that asside. Also, we ran the pool without the spa circulating and it still leaked at the same rate.
• Replaced entire skimmer
• capped skimmer lines and ran pool pump from main drain only

Here is what we have discovered so far:

-As per the first leak detection company, when air was induced into the pool main drain line, water started bubbling to the surface near the equipment pad. Upon further investigation, it appears that there was a 4-inch pipe near the surface, with standing water. My current pool guy does not understand how these two can be linked at all, as he swears that 4-inch pipe is normally not used in pool construction and that an open line like that should not be connected to a closed, pressurized system. Nonetheless, the first leak detection guy said he saw bubbling water coming from the pipe. The second leak detection company pressure tested the pool main drain line with no issues. I am not sure how it could have held pressure, while also bubbling for the first company. The second company did not know about the bubbling. The next piece of evidence came when we capped off the skimmer lines and ran the pool on the main drain line. When we did this, I noticed that the standing water in the 4 inch pipe would pulse, up and down. It would not drain or overflow, but instead just rise up and then rise down. I noticed that whenever I turned the pump on and off, this motion of rising and dropping would intensify for a few seconds. The water in the pipe would rise more than usual, followed by a larger than usual suction of water. Then it would stabilize.

-I dug further down to this abandoned 4 inch pipe and cut into to it to see where it was going. It looks like it goes in the general direction of the pool, just to the right of the main structure. I was able to get a fishing line in there and it went down a straight path for about 30 feet. I do not know what happens after this point.
-We still do not know if this pipe is the issue. It is just the best piece of evidence we have in terms of the leak. My pool guy thinks that it is an abandoned landscape drain line that is no longer in use. I do not understand why the water was pulsing more when the pump turned on or off. To me, it seems like they are linked.


Does anyone have any advice? I can post pictures of the pool and the equipment/plumbing if it helps. We just really want this thing to stop leaking.

EDIT: Here are pictures of the pool and the equipment pad. Let me know if you would like to see something close up. Thanks! rickymerchant1's Library | Photobucket

Thanks, everyone!

 

[jjrr007]

Have you looked into your multiport valve leaking? This has happened to me a few times.

If you put the valve in filter or close, you should not feel any water going down the drain pipe. If it is, I would look into changing the gasket for the multiport valve. If you still feel water going down the drain pipe after changing the gasket, then I would place a cut off valve on the drain pipe.

Let me know if this helps.

 

[pooldv]

Welcome to TFP!

I agree that 4"pipe is rarely used in pool plumbing and that it is often used for drainage. But, the fact that it does stuff in relationship with the pool means something.

First guess
There is a hydrostatic valve under the main drain cover that is tied into that pipe for some reason. Has anyone pulled the main drain cover? Did they introduce air from the pool or the pump side? You should be able to pull the drain cover(s) and plug the holes with screw in plugs to close off the main drain line. If the leak stops leave the plugs and abandoned the drain line. If there is a hydrostatic valve leak then you can just replace that.

Second guess
It is part of a well point loop around the pool. But, that doesn't explain the interaction with the pump.

Add your pool info to your signature so we can better help, more here on how and what, Pool School - Read This BEFORE You Post. Advice will vary depending on pool type.

 

[Rick1]

[h=2]Re: Frustrating pool leak with no progress so far! Please help us!!![/h]

Have you looked into your multiport valve leaking? This has happened to me a few times.

If you put the valve in filter or close, you should not feel any water going down the drain pipe. If it is, I would look into changing the gasket for the multiport valve. If you still feel water going down the drain pipe after changing the gasket, then I would place a cut off valve on the drain pipe.

Let me know if this helps.​

I think multiport valve is also known as the "check valve" and in my case, made by jandy? My pool guy calls it the check valve and yes they have leaked before for us. But do you mean physically leaking water at the pad? It is not doing that. If you mean leaking like in the plumbing, would the water not just go back into the pool? Where else could it go?

- - - Updated - - -

Welcome to TFP!

I agree that 4"pipe is rarely used in pool plumbing and that it is often used for drainage. But, the fact that it does stuff in relationship with the pool means something.

First guess
There is a hydrostatic valve under the main drain cover that is tied into that pipe for some reason. Has anyone pulled the main drain cover? Did they introduce air from the pool or the pump side? You should be able to pull the drain cover(s) and plug the holes with screw in plugs to close off the main drain line. If the leak stops leave the plugs and abandoned the drain line. If there is a hydrostatic valve leak then you can just replace that.

Second guess
It is part of a well point loop around the pool. But, that doesn't explain the interaction with the pump.

Add your pool info to your signature so we can better help, more here on how and what, Pool School - Read This BEFORE You Post. Advice will vary depending on pool type.

Hi! I have updated my signature. Thanks for your inputs! I am not sure if the 4" pipe is connected. We are pressure testing the main drain line again today. Wouldn't it not hold pressure if it was connected to the open pipe? Also, I think they induced air at the pipe by the equipment but I am not 100% sure. I believe this is what they did however, because it was one guy alone. He noticed the bubbling near the main drain line so he must have been at the pad. The abandoned 4 inch pipe and the main drain line are very close to each other, but are not connected at the pad. I have posted pictures for you to see. Thanks!

 

[Pool Tool]

Multiport Valve is part of the sand filter with the handle that selects the filter options; backwash, filter, rinse, recirculate, closed, winterized. This is separate from the check valve.

If the gasket is bad inside the multiport valve (MPV), then water can trickle/flow into your backwash pipe even when your handle is set to filter.

 

[Rick1]

Multiport Valve is part of the sand filter with the handle that selects the filter options; backwash, filter, rinse, recirculate, closed, winterized. This is separate from the check valve.

If the gasket is bad inside the multiport valve (MPV), then water can trickle/flow into your backwash pipe even when your handle is set to filter.

I see, thanks for informing me! I don't think this is the issue, however, because if I am correct, then we don't have a dedicated backwash pipe. It's just a blue hose that connects to the sand filter, and when we turn it on, the water goes where ever we put the hose. If you look at the pictures, you will see the hose but it just sits there coiled up, no water coming from it.

 

[pooldv]

To put pics in your thread copy the IMG code and paste it in your post and the pic will show up in your thread.