I have a small return line leak. Return line will NOT hold pressure. Only lost 1/2 inch running (pump on) all afternoon. With pool filled, pump off,
and returns plugged, pool lost about 1/8" (it's open pool on a waterway so evaporation should be about that). I filled the line with water (from the
equipment side) for about 5 minutes. Used Super Snorkel and injected air from same regulator valve at equipment. Usually, after 1-2 minutes, I will
hear the air hit the water leaked out and it makes nice bubbles 
Now,
hardly no sound at all. Barely even hear the water running through the pvc when filling the line. It is a paver deck, but that usually doesn't deter
from getting a "sounding". Oh yeah, ran a rod at the equipment to check the soil around the return line there. Nothing. 
Any thoughts or ideas?
These ideas have allowed me to solve the tough ones:
1 I had a tough job that i could not pinpoint in november, i usually run my air in at 10psi, got no identifable sound, but was sucessful after
upping the pressure to 20psi
2 I find it much quieter to deliver the air from a tank and not from a compressor, is your super snorkel compressor masking the noise your listening
for?
3 With a paver deck i usually listen with the metal rods instead of the big foot, just remove a few pavers and insert the probe well into the
soil
4 If all of these fail then it is time to PT with helium and invest in a helium detector, a paver deck is the perfect job for helium to be
detected
Bruce
Underwater Pool Repair serving CT & NY
| Quote: |
| Originally posted by LeakControl I have a small return line leak. Return line will NOT hold pressure. Only lost 1/2 inch running (pump on) all afternoon. With pool filled, pump off, and returns plugged, pool lost about 1/8" (it's open pool on a waterway so evaporation should be about that). I filled the line with water (from the equipment side) for about 5 minutes. Used Super Snorkel and injected air from same regulator valve at equipment. Usually, after 1-2 minutes, I will hear the air hit the water leaked out and it makes nice bubbles Now,
hardly no sound at all. Barely even hear the water running through the pvc when filling the line. It is a paver deck, but that usually doesn't deter
from getting a "sounding". Oh yeah, ran a rod at the equipment to check the soil around the return line there. Nothing. Any thoughts or ideas? |
thanks for the input. Probably 98% of the jobs in S.Fla are equipment is: at or above grade and it's never been an issue before now. I usually use pressure at 25psi on first run and if needed, 30 psi on 2nd and/or third run. When those didn't work (neither did the 4th and 5th run), we put water in at equipment and air at return. Nothing. We tried it again. Nothing. Swapped the 2 entry points. Nothing. (I have long hose so I always put my super snorkel as far away as possible (usually about 50 feet or more and AROUND the house and never on concrete (which can amplify the sound). I finally gave in and called in ALD and they found it. Used "tanked" air, jacked the pressure up, and it blew the leaking fitting apart and THEN it was VERY discernible. Not my method of doing things, and luckily it blew apart only the leaking fitting, but it worked and the customer is happy. Thanks for the input. I found out that because it was windy the Helium/Nitrogen would have blown away too fast to be "sniffed". Glad I didn't spend $1500 for a "sniffer" that I would rarely use. thanks for the ideas. I carry compressed air for blowing out clogged vac lines, etc. but not sure I want to use it for leak detection. If it had blown apart a different line, things would not have concluded so well. Do many others use compressed air for leak detection? That kind of unregulated pressure makes me nervous. Input?
I use nitrogen with a regulator. You're asking for trouble without a regulator. In my area 40-50 year old pools are common. And they have original
galvanized plumbing on some of the older ones.
Low pressure swimming pool leaks need to be purged of water before you can hear them. Noise happens fast on big open leaks and no need to let your air
or gas bleed out the other end. On medium size leaks it may take a few minutes to purge some water before you get some noise. On small leaks it's
necessary to purge out some water so you can make noise with the air/gas. Getting a leak to make noise is our challenge. It takes practice to get good
at it. You can see the needle on a 0-30 gage bounce when the leak is making noise most of the time. If you have just air or just water exiting the
leak, no noise will happen at the low pressures we use on pool leaks. On larger leaks add gas and water at the same time, gas up high at the equipment
and water low on the pool end to maintain noise.
--
Hap
I have always used compressed air (scuba tanks) for pressure testing and listening for leaks, you must regulate the pressure, my scuba lp hose
delivers air at 120 psi, i reduce that with an adjustable air regulator ($20 any plumbing store) that is fitted on to my Anderson Pressure Tester,
this allows complete control, safe pressures, and the ability to set any constant pressure you want for listening.
I would never use a PT with water or gas if I did not have a regulator, way to many old pools and pipes
Bruce