Author Topic: Keg line balancing issue  (Read 769 times)

Offline jivetyrant

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Keg line balancing issue
« on: January 26, 2013, 11:19:41 AM »
So I kegged my Gratzer earlier this week and carbed to the recommended 3.6 volumes, which gives me a head pressure of about 24psi.  I ordered a 3/16 polyethylene draft line that is 11' long, the manufacturer lists line resistance as 2.2psi/ft.  I'm dispensing with a cobra tap that stays in the fridge.  The equation I am using for calculating draft line length is as follows:

Length = keg pressure (24) -1 (apparently cobra taps create about 1psi of resistance) / line resistance (2.2 psi/ft).  There is no elevation to take into account.  So, the equation should be

Length = (24 - 1)/2.2 = 10.45.

I cut my line to 10.5', I am using a ball lock, 1/4" flared fitting and just crammed the line over it.  The line is coiled up into a roughly 1' circle, and is sitting more of less on top of the keg.

All seems well on paper, but the beer shoots out of the draft line like a fire hydrant!  Did I miss something?  This will be the first time I've tried kegging a highly carbonated beer so I'm a bit lost. Does anyone else have experience with this?

Offline tschmidlin

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Re: Keg line balancing issue
« Reply #1 on: January 26, 2013, 01:09:51 PM »
What you missed is that the 2.2psi/ft is nonsense.  Turn the pressure down and you will get a much nicer flow.  You can add more line, replace the existing one, introduce some restriction, etc.  But you can't turn the temp down enough to give you 3.6 volumes of CO2 without risking freezing a low alcohol beer like gratzer.

Next time use a much longer hose - we've talked about it in numerous threads, but I would have started with at least 16 feet and cut it down after if needed.
Tom Schmidlin

Offline jivetyrant

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Keg line balancing issue
« Reply #2 on: January 26, 2013, 02:36:21 PM »
Thanks!  I'll try ordering a 20ft line and going from there.

I loved the "2.2psi/ft is nonsense" thing. That's what I get for trusting manufacturer specs!

Sorry if I started a thread on a subject that's already been beaten to death.  I should have known better and searched the forum first!

Regarding the difficulties in getting to 3.6 volumes of CO2, the charts I've referenced say that it's achievable at 24ish psi and 38F.  Are those charts flawed at the extreme high and low ends?

Offline tschmidlin

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Re: Keg line balancing issue
« Reply #3 on: January 27, 2013, 01:15:41 AM »
No worries about not searching, it would be a tough one to find anyway.  And sometimes it is just easier to ask. ;)

Regarding the difficulties in getting to 3.6 volumes of CO2, the charts I've referenced say that it's achievable at 24ish psi and 38F.  Are those charts flawed at the extreme high and low ends?
Sorry I wasn't clear, I meant with as short of a hose as you have you'd need to turn the pressure down to maybe 16 or 18 psi to get a decent flow, and you can't get 3.6 volumes of CO2 at that pressure without dropping the temp below freezing.
Tom Schmidlin