Testing a keg with water

Brewing Processes
1

I had a keg of Ordinary Bitter with a problem of air in the beer line. I switched beer lines, to no avail. I switched the post o-ring, to no avail. Now that the keg is empty, I checked the poppet and dip tube o-rings and don’t see or feel any issues. I had to change CO2 tanks while I was burst carbonating this keg, so I’m wondering if it was over-carbonated. Can I check for air in the line using water in the keg, or will it not develop air in the line like the beer did? I’m almost certain that it won’t foam at the faucet like the beer, but if I can see air in the line like I could with the beer…

Anyway, trying to narrow down the cause of this issue. Any thoughts are appreciated. Thank you.

2

My first reaction reading your post was over carbonation.  Excess CO2 will break out of suspension in the lines when they still idle.

Paul

3

I agree that bubbles in the line more likely means excessive carbonation. If you had an air leak on a system with positive pressure from serving pressure you are more likely to drain your CO2 tank through the leak than take on air from the environment.

4

I normally see this in my beer lines.  I usually carbonate at 10 PSI for about a week before drinking unless I (or more specifically my wife, with IPA) can’t stand to wait, then it is 15 PSI for a couple days and put it on tap.  I serve at around 8 PSI and my lines are 3/8" vinyl and 10 feet long (calculated as per the literature on balancing the serving system).  If I increase the serving pressure, I get way more foam in the glass.  I am going to replace my lines with the ones that Rob Stein recommended (have to look up what they are again) which will hopefully fix the problem.