Difficulty in tracing air piping leak

[High5]

I recently installed a RapidAir piping system 1/2" diameter. Since the garage is new construction, I decided to install the piping in the walls. Once the system was installed, I borrowed my contractors Porter Cable portable air compressor to test it. The first air hose he gave me failed. So he gave me a second. It seems to be fine although I'm not about to spray soapy solution all over it to find out. Anyway, I took the system up to 140psi and shut the compressor off. Two hours later, the gauge showed a 20psi loss. So I sprayed all the fittings with a soapy solution and no bubbles. I've put my ear next to each fitting and also ran the back of my hand across them and no sign of leaks. I did test his air compressor over night for air loss and there was none.

So, I don't know what else I can do. And that's the reason for this thread. Is there any other test you can suggest? Your help is much appreciated.

 

[AZ Pete]

I recently installed a RapidAir piping system 1/2" diameter. Since the garage is new construction, I decided to install the piping in the walls. Once the system was installed, I borrowed my contractors Porter Cable portable air compressor to test it. The first air hose he gave me failed. So he gave me a second. It seems to be fine although I'm not about to spray soapy solution all over it to find out. Anyway, I took the system up to 140psi and shut the compressor off. Two hours later, the gauge showed a 20psi loss. So I sprayed all the fittings with a soapy solution and no bubbles. I've put my ear next to each fitting and also ran the back of my hand across them and no sign of leaks. I did test his air compressor over night for air loss and there was none.



So, I don't know what else I can do. And that's the reason for this thread. Is there any other test you can suggest? Your help is much appreciated.

if you had no further loss of pressure, then you do not have a leak. The original loss was likely due to the air cooling in the system.


Sent from my iPad using Tapatalk

 

[The Cobbler]

if there was no leak down overnight, you're good. as said temp change can do that . did you leave the compressor & hose hooked up while testing?

 

[High5]

if there was no leak down overnight, you're good. as said temp change can do that . did you leave the compressor & hose hooked up while testing?

For the leak down test during the day, I did leave the compressor and hose hooked up. But the overnight test was to check the air compressor itself for any leaks. So for that test I disconnected everything to it. The results the following morning showed no loss of air to the compressor tank.

I did not take into consideration temperature change and pressure drop from it. So I will hook the compressor and hose back up and try one more time. This time I will leave it hooked up overnight and check the gauge the next morning.

I was told that it's possible the tubing may have a pin hole leak. So I will spray a soapy solution over all the tubing as well.

Thanks guys for your input.

 

[Shawn S]

I read this as the air compressor was tested independently overnight to ensure it wasn't the problem. The pipes in the wall were not pressurized overnight.

OP did you test the hose fittings too? Leave it all hooked up overnight to be sure your 20 lbs wasn't a cooling issue.

 

[High5]

I read this as the air compressor was tested independently overnight to ensure it wasn't the problem. The pipes in the wall were not pressurized overnight.

OP did you test the hose fittings too? Leave it all hooked up overnight to be sure your 20 lbs wasn't a cooling issue.

I did test the air compressor independently overnight and that is correct the pipes were not under pressure during that particular test.

As far as the hose goes, I did change one of the fittings for the test. So it was tight and leak free. The other was not checked. The contractor loaned his equipment to me and picked it up today. So my plan is to go to a local rental agency and borrow a compressor and hose for one final check. I will do a soapy solution spray on it during the test as well.

I hope it's nothing more than a temperature change. Thank you for your response.

 

[ford33]

Look closely at any quick couplings or hose reel connections. They tend to leak.

Amazon and others offer a leak detection solution in a bottle. I have used it and it is slightly better than a soapy water solution so if you have a very small leak than that specific solution could find it.

If you have a small system, is is possible to temporarily fill the pipes with water and pressurize the piping with water pressure. For example a garden hose. Then look for a water leak.

 

[High5]

Look closely at any quick couplings or hose reel connections. They tend to leak.

Amazon and others offer a leak detection solution in a bottle. I have used it and it is slightly better than a soapy water solution so if you have a very small leak than that specific solution could find it.

If you have a small system, is is possible to temporarily fill the pipes with water and pressurize the piping with water pressure. For example a garden hose. Then look for a water leak.

The leak detection solution sounds like a great idea. I will check out Amazon. Thank you.

As for the water test, it could be challenging since we have not connected water at the garage yet. But the idea is a good one. I will try the leak detection solution first.

Thanks for the great ideas everybody.

 

[JMQ4]

I have a similar system that was fine when I set it up, then leaked badly once winter rolled around. It was leaking in the 90 degree elbows. I backed off of the screws that held the clips holding the pipe and reseated the elbows and it stopped. I’ve also loosened all of the screws holding clips some to give it room to move. Now that it’s warmer again, it bleeds down slowly over time, maybe 10 lbs/day. But, it has slowed considerably compared to when I first installed the system, so maybe it’s setlled some. I turn the compressor off when I’m done though, so it isn’t an issue for me, just annoying. I tried looking for some means of sealing the joints permantly, but couldn’t find any suggestions that seemed feasible, so I just live with it.

 

[Milton Shaw]

The ultrasonic leak detectors will find air leaks that are very hard to find otherwise. They find vacuum and pressure leaks by listening to the ultrasonic noise the leak makes. I bought one on ebay for less than a hundred several years ago.

 

[Bretny]

Sounds like you should re think the air line in the walls idea again. What are you going to do if something leaks after its drywalled?

 

[High5]

I have a similar system that was fine when I set it up, then leaked badly once winter rolled around. It was leaking in the 90 degree elbows. I backed off of the screws that held the clips holding the pipe and reseated the elbows and it stopped. I’ve also loosened all of the screws holding clips some to give it room to move. Now that it’s warmer again, it bleeds down slowly over time, maybe 10 lbs/day. But, it has slowed considerably compared to when I first installed the system, so maybe it’s setlled some. I turn the compressor off when I’m done though, so it isn’t an issue for me, just annoying. I tried looking for some means of sealing the joints permantly, but couldn’t find any suggestions that seemed feasible, so I just live with it.

Thank you for your experience. The aluminum sleeve inside the tubing may be the achilles heal to this system. The tubing is inside the walls with insulation so I hope it will minimize expansion and contraction. Virtually all the fittings are accessible even after drywall. No elbows were used. Just three "T" fittings. I'll give it one more test and call it good. I, like you, will turn the compressor off at night.

Thanks again.

 

[High5]

Sounds like you should re think the air line in the walls idea again. What are you going to do if something leaks after its drywalled?

There's enough slack in the tubing to pull the distribution blocks out from the wall to gain access to the fittings. No drywall will need to be cut. No elbows were used in this install.

Thanks for your question.

 

[Git]

You should be able to find this at your local Home Depot

https://www.homedepot.com/p/Oatey-8-oz-Leak-Detector-45801/100149747

 

[redmondjp]

If you want to make your own leak detector solution, you can use dishsoap and water with a 1:1 ratio (you read that right). For bonus points, add some liquid glycerin to make the bubbles last longer.

 

[High5]

So I took the advice of several members and bought some air leak detector solution. That worked. Two fittings were found to need additional thread tape. I've checked all fittings four times since and no leaks. Tested the system overnight and air pressure dropped around 6 psi. I'm calling this good. Thanks for all your help and suggestions.