Chasing down water drop in spillover spa.

[david_]

My spillover spa still leaks down fairly quickly even after replacing my check valve with a proper Jandy one. Overnight, it's dropping ~1.5". Confirmed w/ bucket test. I don't yet know at what point it will stop because I don't want to leave my Pebble exposed in this heat for days.

So I could have an underground pipe/plumbing leak, or it could be getting past my 3-way valves and leaking/siphoning down into the pool somehow.

To confirm it's not leaking past valves, would it makes sense to completely drain my pool equipment pad, unscrew and completely open up the 3-way valves (which I believe are above spa water level) so that the spa lines are air-gapped from the pool? At that point I believe no water should be able to flow/siphon out of my spa drain/spillover/returns and if I still see big drops, I have a plumbing issue.

 

[Jimrahbe]

David,

About 90% of the time, spas drains down, when the pump is off, due to a bad check valve in the line that provides the water for the spa spillover.

The best way to find the problem is to allow the spa to drain down until it stops.. But I certainly understand why you do not want to do this right now.

Please post several more pics of your equipment pad, from different angles, so we can understand how things are plumbed..

If you do that, we should be able to provide you with some suggestions on what you can do next.

Thanks,

Jim R.

 

[david_]

Sure. You can see where I've isolated the spa water with the red lines for this test (combination of check valve and 3 way).

I should add.. I've lost 50ppm CH in a month.

 

[Jimrahbe]

David,

Thanks, for the pics..

If we assume that you have an actual leak into the ground (unusual) it could be a broken pipe or a leaking spa light..

As a test, put the system into the spa mode and run it overnight and see if the water in the spa still drains down.. (No heater of course..)

If it does continue to drain down, the water has to go somewhere..

To test the spa jet lines, you would have to remove all the jets and plug them and then pressure test the line..

If this were my pool, I'd do the following..

1. Rebuild both the Intake and Return valves with new Diverters and O-rings.
2. Make sure that the Spa Return check valve does not have any excess glue where the flapper seats..
3. I'd wait until it is cooler and allow the spa to drain down and see where it stops.. If it drains down well below the jets, it would mean the jets line is not bad. If it drained down to just below the light it would point to the light leaking.. etc..

Please let us know if you come up with a fix..

Maybe our other members might have to better ideas...

Thanks,

Jim R.

 

[david_]

Sounds good. I'm going to continue this this test as long as I can, until my water drops below the tile.
After ~25hrs:

• Spa level has dropped 1.5".
• Bucket level is 1.375" higher than spa, meaning it has lost about 1/8" to evaporation as they started out even.

Tomorrow, I should see

• Overall spa level drop 3" (edit - confirmed 3" drop after 48 hrs.. almost down to plaster)
• Bucket level another 1/8" lower than today's mark. (edit - more like 3/8" total evaporation in 2 days)

There's a chance the rate of loss in the spa slows down as it drops below my spillover stone, which would make me very happy. (edit - does not seems to be slowing down now that it's below the stone level)



Edit - After 71hrs:

• Overall spa level drop 4.5" (1.5" consistently for 3 days, even when below tile line)
• Bucket dropped another 1/4", which seems about average daily evaporation
• When I pumped spa back full (4.5") pool dropped 1/2", which means if spa is draining into pool, the net effect is ~0.16" per day, which would make pool evaporation seem very minor. Another potential test there.

 

[Jimrahbe]

David,

Spas can leak into the ground, but not often.. Most of the time the problem is back at the equipment pad.

Thanks,

Jim R.

 

[david_]

Was thinking about plugging my drains when I saw these covers appear to be screwed directly into the plaster? Can these be removed?

Edit - better pic -

 

[Jimrahbe]

David,

The covers are screwed into the PVC drain underneath.. Just remove the covers and while you are in there, remove the excess plaster..

Thanks,

Jim R.

 

[david_]

Quick update.. with spa drains plugged (best I could), still saw 1.5" of drain down in 24 hrs.

So now I've plugged all returns into the spa with 1.5" pvc plugs and will see if I'm losing water through them.



8/27 Edit - still lost 1.5. Snugged up plugs a bit and will retest one more time before sealing light conduit w/ butyl tape to see if that line has been compromised. Only about $50 invested so far vs. $500+ for a pro to come out.

Forgot to add - before butyl, I'll do a 24hr running test.

8/28 Edit - reassembled everything and was running my spa-on test when I realized my drain plugs all this time were most likely not tight enough/stopping potential flow. So I'm back to my initial test with only plugged drains to see what I lose over the next day.

8/29 - Still losing water with snug drain plugs.

8/30 - Still losing water with butyl tape in light niche.

Going to pause on this for now and wait until I can let the spa drain down for several days to see where leak stops.