Kegging Pressure and Line Confusion (balanced system)!!!

[craniumbrew]

Hi Everyone,

New to the forum and to kegging and am confused by a few things. I am working on making a balanced system and the numbers don't seem to be right at all. I have been looking at force carbonation charts and I understand that if I want my beer to have 2.5 carbonation at 40 degrees F then i have to set my regulator at 13 psi. Here is where the confusion starts.....

Is that 13 PSI just to get the beer to 2.5 or does that also include dispensing....I think is it only to get the beer to 2.5. I also want to make a balanced system and my keg setup came with 5ft of 3/16 ID line. From what I've read my line loses 3 psi/ft, so 15psi for the whole line plus 1 psi for the picnic tap and 1 psi for the beer to be dispensed, so from keg to glass I lose 17 psi which means i have to set my regulator to 30 PSI!!!!

This seems crazy high to me and I'm just looking for some input...

Thanks!

[Cody]

You're right: that's crazy high. What is meant by a "balanced system" is that the pressure drop of the liquid output caused by the resistance of the beer line is equal to the pressure of the gas input. So if you set your regulator to 15 psi of CO2, and you have your 5 feet of line for a 15 psi pressure drop, you should have a perfectly balanced system and the beer should not flow at all, even without a tap on. This is of course theoretical. If you want 1 psi dispensing pressure, you either increase your regulator pressure to 16 psi, or you remove 4 inches of beer line. For a more in depth explanation of this, read the sticky in this forum entitled "Brand spanking new to kegging." It has tons of good info.

http://www.thebrewingnetwork.com/forum/viewtopic.php?f=5&t=8715

[Kbar]

Isn't 3/16" ID beer line rated at 2psi/ft pressure drop? I run 10 Psi for most of my beers with the same 5 ft. of line. Works well. 40F may be a bit high for your common beer serving temperature too.

[Cody]

If it's vinyl, it's rated at 3 psi/ft, if it's PE it's 2.2 psi/ft (according to BeerSmith).

[mordantly]

my beer temp is ~35F. 6 feet pvc 3/16. 12 psi. pours with a scosche of head. figure 2 psi per foot.

[ajdelange]

So if you set your regulator to 15 psi of CO2, and you have your 5 feet of line for a 15 psi pressure drop, you should have a perfectly balanced system and the beer should not flow at all....

If there is no flow there is no pressure drop in the line. If he put 15 psig on the beer and had 5 feet of tubing rated at 3 psi per foot the flow rate would be 2 Oz per sec. This is because the published pressure drop numbers are based on a 2 Oz/sec flow rate which was chosen because at that rate it takes 6 seconds to fill a 12 Oz glass - a time deemed reasonable for a busy bar tender.

[scotchpine]

+1 AJ. I think that's just what I'm getting too. Setting regulator at 9psi (after force carbing) with 5' of 3/16 lines. About a 6 sec 12oz pour at 36 degrees with a 2 finger head. I think I'm balanced.