Help with bucket test results

[JeffJeff]

I have been suspicious of a leak for a while in my brand new gunite pool. I have been having to run the fill line for 60 to 70 minutes every other day to keep the water level halfway up the tile.

Here are the results of the bucket test I recently ran. PB is saying this water loss is normal. I disagree. Let me know your thoughts.

12 hours, no pump running = 1/4" water loss
12 hours with pump running, no water features, no swimming = 1/16" water loss
12 hours, no pump running = 1/8" water loss

Total loss in bucket (36 hours) = 5/16" water
Total loss in pool (36 hours) = 3/4" of water
Difference between bucket and pool in 36 hours = 7/16" (about 1/2" difference)

Pool seems to lose most water overnight compared to when the pump is running.

 

[JohnT]

Higher loss with the pump off points to a crack in a suction line. The crack will tend to be pulled closed while the pump is on, and gaps open when the pump is off.

 

[PaulR]

12 hours, no pump running = 1/4" water loss
12 hours with pump running, no water features, no swimming = 1/16" water loss
12 hours, no pump running = 1/8" water loss

Total loss in bucket (36 hours) = 5/16" water
Total loss in pool (36 hours) = 3/4" of water

I get 1/4 + 1/16 + 1/8 = 7/16 not 3/4 (12/16). Not saying you didn't lose 3/4 and have a real problem, but the report doesn't balance the way it should.
--paulr

 

[Bama Rambler]

Are you seeing any air bubbles in the pump strainer basket when the pump is running?
Are you seeing any water pooling when the pump is off?

I agree with JT, it's got to be a suction side leak. It could be sucking in air or closing off under vacuum.

Paul -- I didn't assume the 36 hour bucket test was during the three separate 12 hour tests.

 

[JeffJeff]

Thanks for the replies.

PaulR-
I get 1/4 + 1/16 + 1/8 = 7/16 not 3/4 (12/16). Not saying you didn't lose 3/4 and have a real problem, but the report doesn't balance the way it should.

Sorry for the confusion. I measured at 12 hour intervals for a total of 36 hours. The numbers reported at the 12 hour intervals are pool water loss minus bucket water loss.

The summary for the 36 hour period is 3/4" pool loss, 5/16" bucket loss = 7/16" total loss in 36 hours.

Bama Rambler - I have some small bubbles in the pump basket when the pump is on. Not sure what you mean by water pooling, but I do not have any wet areas that I am aware of.

 

[Bama Rambler]

Having bubbles in the pump basket and losing water is a good indication that you have a suction side leak. Since you don't see any water or wet spots I'd suspect that it's underground. Looks like it's time to call the PB to task about finding and fixing it.

 

[JeffJeff]

Update:

The pool builder finally agreed I "may" have a leak so they agreed to come out and do their own test.

They ran a 24 hour test with the pump off. They "eyeballed" the bucket on this test and guesstimated 1/2" loss.

The second was a 24 hour test with the pump running. They did not use a bucket for this test, just tape on the tile. Again claimed 1/2" loss and are saying this is normal.

I question their testing methods and feel we are going to end up in a stalemate. Has anyone used a 3rd party for leak detection? What are the approximate costs of this for an in-ground gunite pool? Any other suggestions to deal with a stubborn PB?

 

[X-PertPool]

Your results are hard to understand. Try this.

Fill bucket half way with pool water. Place bucket on steps of pool mark water level of pool on outside of bucket mark water level inside bucket wait 24 hours measure results with ruler. Do this test twice once with pool running normally and once with system off. You can also do it a third time with system off and winter plugs installed to focus soley on shell. If there is no leak bucket and pool should lose same amount