Author Topic: Proper 'holding' pressure & length of tap line?  (Read 1241 times)

Offline Beer Monger

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Proper 'holding' pressure & length of tap line?
« on: March 21, 2011, 12:34:55 PM »
Hi guys.  I've been a homebrewer for quite a while, but I was out of it for a couple of years and am just getting back into the swing of things. 

I've been kegging my homebrew for years, but I always seem to have to release some pressure on my keg before serving off a glass, unless I want way too much head.

My questions are:

-What PSI do your keep your kegs at once the beer is fully carbonated. 

-What should the lengh and internal diameter of the cobra tap line be to tap off a pint without having to adjust the CO2 pressure level or pull the keg's pressure relief valve first? 

Thanks! 
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Offline tschmidlin

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Re: Proper 'holding' pressure & length of tap line?
« Reply #1 on: March 21, 2011, 01:48:07 PM »
There are two questions you need to ask yourself:
How many volumes of CO2 do I want in my beer?
At what temperature do I want to serve my beer?

That will tell you how many psi to use.  The hose diameter is up to you, but most are 3/16".  That and the pressure will determine how long the line should be.

This should give you all of the information you need, but feel free to ask questions:
https://files.pbworks.com/download/xC8MJrMxXa/draftquality/18182336/DBQM_Full.pdf
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Offline maxieboy

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Re: Proper 'holding' pressure & length of tap line?
« Reply #2 on: March 21, 2011, 01:56:09 PM »
I'm currently running @ 45*, 15#, 10' of 3/16 beer line, and cobra taps. No need to bleed, great pour.
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Offline Beer Monger

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Re: Proper 'holding' pressure & length of tap line?
« Reply #3 on: March 21, 2011, 08:15:58 PM »
OK.  Thanks for the info guys.  I have a couple of weeks before I keg.  :) 
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Offline oscarvan

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Re: Proper 'holding' pressure & length of tap line?
« Reply #4 on: March 22, 2011, 05:17:53 PM »
FWIW, the first beer after sitting for a while will have more foam, as the beer in the tap warms while sitting. Me, 2.2 to 2.5 volumes, 10-12 psi at 45º, 12 feet of beer line. What I am doing now is to have a glass by the taps where I put the first 3 seconds after I haven't tapped for a while, put it aside and tap away. Eventually that foam settles down to liquid and I add it to the third or fourth beer.....
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Offline Beer Monger

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Re: Proper 'holding' pressure & length of tap line?
« Reply #5 on: March 24, 2011, 09:21:42 AM »
The beer in my tap line shouldn't warm.  I have the kegs in the fridge. 

I'll have to experiment w/ the pressure and line length to see what works best for me. 
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Offline oscarvan

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Re: Proper 'holding' pressure & length of tap line?
« Reply #6 on: March 24, 2011, 04:07:25 PM »
When in doubt, go long.
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Offline newrocset

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Re: Proper 'holding' pressure & length of tap line?
« Reply #7 on: March 24, 2011, 05:00:05 PM »
My keg is in the fridge too.
I have about 6' of 3/16 line to a picnic tap.

Keep in mind this was my first keg ever, but I found that carbing at a pressure 12psi worked fine.
After a while I took it down to around 8-9 psi for a serving pressure and that worked fine.
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Offline gsandel

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Re: Proper 'holding' pressure & length of tap line?
« Reply #8 on: March 26, 2011, 07:29:16 AM »
Quote
Keep in mind this was my first keg ever, but I found that carbing at a pressure 12psi worked fine.
After a while I took it down to around 8-9 psi for a serving pressure and that worked fine.

The 8-9 psi is a function of your 6' beer line.  The problem is, though, that your carbonation level drops from your 12 psi to your serving pressure over time (as you serve beer).  That is why we are talking about a "balanced" system....where the length of beer line from the keg to the faucet equals the pressure in the beer and keg.  Too long a hose and the flow of the beer to your glass is too slow, too short and you get more foam than beer in your glass as the co2 rushes to escape.  Temperature also plays a part.  So, if you are serving at 40 degrees at 8-9 psi, you have 2.1-2.2 volumes of co2, where you were at 2.5 volumes at 12 psi...if you want 2.5v, then lengthen your hose a foot or two....if you are good at 2.1v, just set your regulator at 8-9 psi to carb and leave it for a week, and leave to serve.
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