Bubbles in beer line

A forum to discuss the various ways of getting beer into your glass.
Fil
Telling imaginary friend stories
Posts: 5229
Joined: Sun Oct 16, 2011 1:49 pm
Location: Cowley, Oxford

Re: Bubbles in beer line

Post by Fil » Sun May 11, 2014 12:11 pm

if your pouring foam and not just clearing the co2 break out thats occurred between sessions in the line? your possibly releasing the beer at the tap at to high a pressure,

Idealy the pressure difference at the point of release wants to be minimal, a big sudden drop in pressure can stimulate a foam out.. I found details for all beerline sizes on a US brewsite but only remember the microline 3/16" line restricts pressure at about one to two psi per foot length.. the larger bore beer lines do restrict pressure but its nominal along the lengths we employ, if running for 20m or more it may be worth looking up.

So assuming a target pressure drop at the tap of 1-2psi max, and a keg pressure of 7psi, a short length of 3-4ft of 3/16" microline between the keg and tap should balance the keg pressure.

I have a 6ft length of micro line which allows me to serve beers at upto 15psi without any foam probs, for lower conditioned beers upto about 8psi on my reg flow control taps work fine but become a pita to set with higher conditioned beers

User avatar
mozza
Under the Table
Posts: 1031
Joined: Thu Jan 31, 2013 7:58 pm
Location: Essex

Re: Bubbles in beer line

Post by mozza » Sun May 11, 2014 4:00 pm

Fil wrote:if your pouring foam and not just clearing the co2 break out thats occurred between sessions in the line? your possibly releasing the beer at the tap at to high a pressure,

Idealy the pressure difference at the point of release wants to be minimal, a big sudden drop in pressure can stimulate a foam out.. I found details for all beerline sizes on a US brewsite but only remember the microline 3/16" line restricts pressure at about one to two psi per foot length.. the larger bore beer lines do restrict pressure but its nominal along the lengths we employ, if running for 20m or more it may be worth looking up.

So assuming a target pressure drop at the tap of 1-2psi max, and a keg pressure of 7psi, a short length of 3-4ft of 3/16" microline between the keg and tap should balance the keg pressure.

I have a 6ft length of micro line which allows me to serve beers at upto 15psi without any foam probs, for lower conditioned beers upto about 8psi on my reg flow control taps work fine but become a pita to set with higher conditioned beers
That makes sense actually :) i think I'll persist with the low serving pressure though as I like emulating cask ale carbonation levels. Definitely worth a try though for pales and lagers :)
Cheers and gone,

Mozza

Post Reply