Pressure Test Issue

[edramshaw]

I got a call from a customer that said they had a gas leak. I came in the next day but they were open so I could not do the pressure test as I would like but I was able to do this....I shut down all 16 manifolds and then closed the tank with no leaks showing on the high pressure gauge after 2 minutes. This told me the leak would have been between the coupler and the manifold (right?). I then untapped kegs, one at a time and opened the respective manifold and repeated the same test. I retapped each keg and closed each manifold after completing the test. (I did this so that there pouring of the other beers did not result in a failed test). I went through the whole system like this twice with no signs of a leak. Is there something using this methodology that would give me a false reading? It seems like it should work. Any ideas for how else to go about this test to get a better idea of where the leak is coming from. The high pressure gauge read 700 when I was there, 600 at the end of the day and 500 when they came in this morning so there is definitely a leak somewhere. They usually turn the valve on the regulator off at the end of the night but I asked them to leave it on last night and had them perform the leak test over the phone. It dropped after 5 minutes. It seems odd as I would expect something leaking that much would present itself quicker doing one of these tests. Any thoughts/ideas or direction would be appreciated.

[BrewGuru]

I think your troubleshooting methodology is fairly sound, but I think your test left out a step / overlooked the possibility of the leak being even further downstream than you tested for.

I would suspect a faulty coupler or keg pressure seal.

With your test conducted having the handles of couplers in the raised position, you were depending on the internal seals of the couplers themselves to hold the system pressure, which you indicate they did, and everything upstream did as well.

So your leak is downstream somewhere, so the only place to look is the couplers / kegs themselves. If you can, conduct your test when no pours are occurring with the kegs fully coupled. Fully pressurize the system and then close all the manifold valves, opening them one at a time until you find your leaker and then investigate further.

If the establishment is pouring any Hoff-Stevens, Golden Gate, or other specialty kegs, check these out first.

Good luck!

[Larry Tapper]

The leak could be between the tank and primary regulator, often this is the case of not using a new gasket when they change tanks

[edramshaw]

If the leak were there I would expect a pressure test to fail when running it open from the regulator to the manifolds. The pressure test passed this but failed when I opened them up. Am I overlooking some reason why the regulator could still fail? Thanks for the input.

[DCullender]

I'm siding with BeerGuru on this one. Your test was sound. I would check all bottom seals on the couplers and the black rubber seal on the kegs. If either are nicked or worn they will leak. Also, check for any debris on top of a keg.

An easy, all though messy, test for the coupler connection is a little water squirted on the connection of the coupler and keg, then look for bubbles.

Also, I've been using the gas leak detector sold by MM and love it! It has reduced my leak detection time by at least 2/3. I have a place here in Richmond, Capital Ale House, with 80 drafts, found the leaks and was in and out in less than 1 hour.
MicroMatic part No.: 5550-RX1 CO2 DETECTOR

D

[edramshaw]

I've been looking at that myself. Sounds like it works pretty, may be time to invest.

[happytappy]

I borrowed one of the detectors and it pinpointed a leak I could not find for 1 hour plus. It turns out it was the economy style secondary regulator, the relief valve on the back was leaking. It would not make the foaming stuff bubble but did make the detector go off. Always start with the basics, this was a rare occurrence.

[TAPMAN]

I have thought about the leak detector and have not heard much good about it. This is the first good that i have heard. Some of these gas leaks are a real @#$%@ to find and enough to drive a man to drink. Oh yeah, like we need a reason. Anyone else use them and what do you think?