Leak during pressure test - is this acceptable?

[greenwood207]

In reality no pressure loss from the skimmer should be noticed and if their is it’s an easy fix. The only pressure difference should be from the temperature changes due to the plumbing being exposed in the trenches. When their is a difference and no recovery that would also indicate a possible leak.
The plumbing system is designed to have no leaks at all, not even a single drip from glued joints or threaded cuplings.
The faucet is typically on the manifold only and not on the skimmer loop.

Thank you, this is most helpful. What PSI changes under manifold would you expect from temperature changes? I will ask the PB to check again since I understand the skimmer should have no pressure loss. I am confirming ours look like the one in your picture.

My concern is that the PSI change (32 to 27 over 3 days) cannot be only due to temperature changes only (also note we are in generally moderate temp of high 85, low 65s).

 

[SoDel]

Hi SoDel, you are correct. we had passed the plumbing inspection -- the PB had pressurized the system 15 minutes before inspector arrived and it held at 30 PSI for 10 minutes. We have had several moving parts to address any PSI declines so the PB put in a manifold to eliminate any sources. Under the manifold, we've seen a decline from 32 PSI to 27 over 3 days. Hope this clarifies.

Yes, you’ve been very clear — no questions there. Just the intersection of standard procedures, the “rules” and actual in the field reality can be really interesting. Based on this situation, ASME may need to go back to the drawing board lol. I’m imagining a large structure or industrial process that passes all tests but is potentially filled with “drip, drip, drip” leaks.

 

[SoDel]

It occurs to me that your PB may be well served by investing in a pressure gauge with much higher resolution. It would make seeing a pressure drop faster so you wouldn’t need to deal as much with temp and atm induced changes.

 

[PoolGate]

You test the drains and returns at the same time? How do you do that?

This is what I'm asking, how is it done. I seem to remember my pool was pressure tested with air intake and returns.

 

[AQUA~HOLICS]

My remarks to pressurizing the plumbing is in regards to new pool construction, all the pipes are capped off.
Spray a soap solution on the the two pipes that thread into the skimmer and look for bubbles.
On a manifold system the pressure may change during the day but recovers.
5 lb. loss over 3 days is a concern.

 

[SoDel]

This is what I'm asking, how is it done. I seem to remember my pool was pressure tested with air intake and returns.

For the returns, you’d round up seven plugs. Plug the returns. Fill with water at an above ground location at the pad (when mine were done, for example, the PB used a return stub coming up that would be eventually plumbed to the SWG, filter, pump, etc. through another valve that could route return water to the spa, etc. — once it’s above ground, the whole leak thing is much less of a panic). Pressure test for leaks.

If your skimmers are on a separate pipe from the drain, similar process. Plug the skimmer intakes, fill pipe with water, pressure test.

Drain, same. Plug the drains, etc.

Just a methodical process because once the trenches are backfilled, a simple leak repair becomes a lot less simple.

 

[greenwood207]

My remarks to pressurizing the plumbing is in regards to new pool construction, all the pipes are capped off.
Spray a soap solution on the the two pipes that thread into the skimmer and look for bubbles.
On a manifold system the pressure may change during the day but recovers.
5 lb. loss over 3 days is a concern.

Thank you! This is most helpful and informative.

 

[greenwood207]

1-2 psi max loss with a manifold. Did the plumber add water to the system to help show location of leaks if any prior to pressurizing ?
5 psi seems excessive in 3 days and true that the skimmer is most likely area for the leak but also look for a faucet bib threaded in the above ground lines. Spray soapy water on those two areas to confirm.

Could you clarify if 1-2 PSI loss with manifold is expected? Would this be due to temperature changes in which I could expect the pressure to go down at nighttime but then go back up to baseline during the day? How long do you recommend tracking PSI changes to ensure there is no leak? Thank you!

 

[AQUA~HOLICS]

The 1-2 PSI loss is not expected but the maximum I would allow before having a concern. Time frame is different on every job due to the scheduling between plumbing and inspection for tracking the PSI but typically it’s around a week.
Inspectors allow for a leak down of up to 5 PSI but that shows the pressure is going somewhere and the system should be air tight, I see most jobs with no leak downs on manifold systems being tested.
Yes you will have differences in the pressure from daytime heating but very minimal.

 

[greenwood207]

The 1-2 PSI loss is not expected but the maximum I would allow before having a concern. Time frame is different on every job due to the scheduling between plumbing and inspection for tracking the PSI but typically it’s around a week.
Inspectors allow for a leak down of up to 5 PSI but that shows the pressure is going somewhere and the system should be air tight, I see most jobs with no leak downs on manifold systems being tested.
Yes you will have differences in the pressure from daytime heating but very minimal.

Thank you. The PB decided to separate out the pipes into separate manifolds to be able to locate the source. There is now 6 gauges all pressurized to 30 around mid-afternoon. The pressures started to drop in early evening (6 PM), or at least when I checked and continue to have dropped this morning. Any thoughts? Should I ask the PB to leave it pressurized and track for the full week? We are past inspection period but I am concerned that the pressure is not holding.

Time	L to R #1	#2	#3	#4	#5	#6
16:00	30	30	30	30	30	30
18:00	28	29	29	29	28	28.5
7:00	25	27	26	26	24.75	26.5
11:30	27	29	27.75	28	26	28
13:40	28	29.5	29	29	27	29

 

[AQUA~HOLICS]

What are #1 & 5 testing?
Was the skimmer pipes soaped?
Yes, I would keep testing them.

 

[greenwood207]

What are #1 & 5 testing?
Was the skimmer pipes soaped?
Yes, I would keep testing them.

#1 connects to the spa and #5 is the skimmer. I had soaped the skimmer pipes in the connection area but did not see anything; the PB checked the skimmer yesterday (visual only) and did not note anything. The PB mentioned that #5 might be due to a less sensitive gauge, could this be the reason? I will try the soap again tomorrow, should I see bubbling if there is a leak?

Here is an update on the reading over the past two days. We will keep it under pressure until tomorrow too and if the pressure continues to trend, would you suggest to keep it through the weekend?

Day	Time	#1	#2	#3	#4	#5	#6
0	15:55	30 (29)	30	30	30	30	30 (29.5)
0	18:00	28	29	29	29	28	28.5
1	7:15	25	27	26	26	24.75	26.5
1	16:08	28	30	29	29.5	27.3	29
2	7:40	24	26.5	25	25.5	23	26
2	16:00	26	29	26.75	28.25	25	28.25
3	7:30	23.5	26	23	25	21.5	26
3	16:00	26.5	29.25	26	29.5	30 (PB fixed)	28
4	9:00	24	26.5	23	25.25	25	26
4	16:30	26	29	25	28	28	28
5	7:45	23.5	26.25	22	25	25	26
5	16:45	25.5	28.5	24	27.5	27	28
6	8:00	22.5	26.25	21.5	25	25	26
6	16:00	25	29.5	24	28.5	28	28.5
7	8:00	21.25	26	20.5	25	24.75	26
7	16:00	24.5	30	23.25	28.5	28.25	29

 

[AQUA~HOLICS]

Yes the gauge could be the reason.
Yes bubbles will appear from the escaping air.
I would keep the pressure test going just for more detailed records.

 

[PoolGate]

I think this is much ado over absolutely nothing.

 

[SoDel]

I think this is much ado over absolutely nothing.

I would have said the same before encountering this thread. On the first go-round, it passed a traditional pressure test, with water for the fill, yet the reality was it still had a leak. It seems (beyond seems, apparently proven) that @greenwood207 is on to something but the difficulty is determining normal variances and inevitable imperfections in any test setup, versus another leak(s).

 

[1poolman1]

#1 connects to the spa and #5 is the skimmer. I had soaped the skimmer pipes in the connection area but did not see anything; the PB checked the skimmer yesterday (visual only) and did not note anything. The PB mentioned that #5 might be due to a less sensitive gauge, could this be the reason? I will try the soap again tomorrow, should I see bubbling if there is a leak?

Here is an update on the reading over the past two days. We will keep it under pressure until tomorrow too and if the pressure continues to trend, would you suggest to keep it through the weekend?

Day	Time	#1	#2	#3	#4	#5	#6
1	15:55	30 (29)	30	30	30	30	30 (29.5)
1	18:00	28	29	29	29	28	28.5
2	7:15	25	27	26	26	24.75	26.5
2	16:08	28	30	29	29.5	27.3	29
2	18:34	26.5	28.5	27	28	25.75	28
3	7:42	24	26.5	25	25.5	23	26
3	16:12	26	29	26.75	28.25	25	28.25
3	18:00	25.5	28	25.25	27.5	24	28
4	7:30	23.5	26	23	25	21.5	26

Ambient air temp has a lot to do with variations of pressure in your pipes, especially if they are in the sunlight. Not sure where in California you are, but your numbers seem to correlate to the temperatures we have been experiencing, hot days, cool evenings, cooler nights.

 

[Myburneraccount]

If the system were air tight and ambient temperature was the cause for the pressure drop, wouldn’t the system go back to the original pressure when things warm up? If not, wouldn’t that indicate less air/water which means leak somewhere?

 

[1poolman1]

If the system were air tight and ambient temperature was the cause for the pressure drop, wouldn’t the system go back to the original pressure when things warm up? If not, wouldn’t that indicate less air/water which means leak somewhere?

Have you checked under identical circumstances, exact air temp, sunlight conditions, overnight cooling? The fact that it is lower earlier in the day after a cool night and increases with the temperature as the day goes on seems to indicate that the system is solid and you're worrying over little changes that mean nothing. If there were a leak, as the temperature went up, more would leak out under more pressure or there would be no increase in pressure because of said leak, and soon there would be no pressure. Have you seen water leaking? Heard air?

 

[greenwood207]

Have you checked under identical circumstances, exact air temp, sunlight conditions, overnight cooling? The fact that it is lower earlier in the day after a cool night and increases with the temperature as the day goes on seems to indicate that the system is solid and you're worrying over little changes that mean nothing. If there were a leak, as the temperature went up, more would leak out under more pressure or there would be no increase in pressure because of said leak, and soon there would be no pressure. Have you seen water leaking? Heard air?

The temperature over the past couple weeks have been consistent and I have checked consistently at the same time (eg. consistent sunlight conditions, cooling etc). Please note that before the pipes were changed into separate manifolds per pipe, the system was under 1 manifold and there was a small leak was detected. This small leak did not lead to an immediate drop in pressure as most PB have indicated but instead 4 PSI over 12 hours -- the PSI went up slightly during midday but ultimately went slowly down. No air was not heard and the water leak was a small one where you would only see the leak at specific angle and droplets were every 2 minutes so not visually apparent. This small leak is what lead to further assessment of each pipe under its own manifold.

 

[SoDel]

The temperature over the past couple weeks have been consistent and I have checked consistently at the same time (eg. consistent sunlight conditions, cooling etc). Please note that before the pipes were changed into separate manifolds per pipe, the system was under 1 manifold and there was a small leak was detected. This small leak did not lead to an immediate drop in pressure as most PB have indicated but instead 4 PSI over 12 hours -- the PSI went up slightly during midday but ultimately went slowly down. No air was not heard and the water leak was a small one where you would only see the leak at specific angle and droplets were every 2 minutes so not visually apparent. This small leak is what lead to further assessment of each pipe under its own manifold.

Out of curiosity, was anyone able to assess the cause of that small leak? Except for screwups, pipes generally don’t leak. What went wrong? Can that fault be extended to other leaks, like the apprentice was sloppy and did x which resulted in leak(s)? Prep the pipe, prime and glue the pipe — not rocket surgery.