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Overly Foaming Draft Beer


Marc Kovach — Dover, Pennsylvania asks,

When I keg my beer, I force carbonate for two weeks at 14–15 psi. At this time, I have found carbonation is right where I like it and I get just the right amount of head in my glass. This condition lasts until I get about half way though the keg (approximately 11⁄2 months later) when I start getting half beer and half foam. This tends to be worse with hoppier beers. The 14–15 psi is what I calculated to result in 12 psi after pressure loss through my lines. My dispensing lines are about 5–6 feet long. Any ideas what may be causing this?

Your problem is caused by overcarbonation that is slowly occurring over time. Let’s dig into what you are observing over time beginning with your method of carbonation. Based on your question, I
Response by Ashton Lewis.