Leaking Kegs (CO2)

[babennetts]

I just acquired two second hand kegs and have replaced all of the O-rings, the poppet valves, and the pressure relief valve. I recently put beer in each of them, put CO2 in the kegs at 30 psi, and checked for leaks with soapy water, Star San solution, and by submersing the top of the keg in water. No visible or audible leaks.

I have come back the following morning and the pressure in the kegs has dropped to 20 psi in one keg and 15 psi in the other. The pressure continues to drop but seems to stabilize at around 8 to 10 psi. I checked the pressure using a pressure gage connected to a quick-disconnect gas fitting. The keg with the greatest pressure drop has the lowest amount of headspace. I have done this several times and the trend is consistent.

Since I don't seem to have any leaks, I am wondering if the possible decrease in gas measurement could be due to the beer absorbing the CO2?

 

[mbbransc]

Are you disconnecting the gas after filling the keg? Sounds like CO2 is going into solution. Everything is fine.

 

[TheMadKing]

Was the beer warm when you hooked up the gas?

was the CO2 tank warm when you hooked up the gas?

It sounds like a combination of CO2 being absorbed into solution and your temperature dropping. If those leak tests showed no leaks, you're fine! (just don't overcarb your beer by keeping it charged to 20 PSI for too long)

 

[babennetts]

The beer and the CO2 tank were both cold and I did disconnect the gas line after charging the kegs to 30 psi. Thanks for reaffirming what I was thinking regarding the CO2 being absorbed into the kegs.

Another question, how noticeable should leaks be if I am using a Star San Solution. The solution doesn't seem to be all that "bubbly" to me.

 

[mbbransc]

Depends. I drained a CO2 tank overnight Saturday because a new keg had a slow leak in the PRV. I hooked up another tank on Sunday, added pressure and disconnected. Checked it a couple hours later and it had no pressure. I believe the floss holding the dry hop may have gotten caught up in the PRV while purging oxygen. But I didn't see any bubbles at all. Around the gaskets, they are generally easy to spot with StarSan.

 

[TheMadKing]

You have to coat the star San on pretty thick.. It's better to just drip it on out of your hand or the bottle than spritz it, but the bubbles should be very noticeable anywhere its leaking if you've properly coated with star San.