Balancing keg lines

[DrunkenSatyr]

This is a very easy yet often time ignored first step in setting up your kegerator. The math is simple and takes very few steps or measurements to resolve. I will assume that you are ok with standard beer carbonation. If you want multiple beer carb levels then you will need multiple regulators and multiple line lengths to keep foam free pouring. 12 psi is kind of the generic perfect pressure for most systems.

Regulator Pressure = (Length of Beer Line in Feet x Resistance of beer line) + (Heights of tap above kegs x 0.5)


Beer line resistance:

3/16 id is 2.7
1/4 id is 0.7


Common example:

5' of 3/16" hose and the tap is 2' above the keg.

Pressure at regulator should equal (5 x 2.7) + (2 x .5)
13.5 + 1 = 14 psi. Since 14 is a bit high, I would rather go back and decrease the hose length to hit the 12 psi mark.

4' of 3/16 will change it to:
4 x 2.7 + 2 x .5 = 11.8 or round that to 12.

[Ó Flannagáin]

Awesome, I never knew this!

[DrunkenSatyr]

Ok just found it but if you want to keep your beer close to style and you use the above formula to find your line length, here is a calculator that uses your temp and desired Co2 volume for force carbing.

http://www.tastybrew.com/calculators/carbonation.html

[trippivot]

Ok now, Why is the fluid temperature omitted from your formula?

assuming you are using CO2 what about Nitrogen?

as short as my lines are I never get over 7psi/keg

[DrunkenSatyr]

The temp calculation is in the link. Temperature does not effect the line balance, the carbonation level does. Temperature does effect the carbonation level but that is beyond the point of this equation.
This is another good link for temperatures and volumes of Co2 http://hbd.org/clubs/franklin/public_ht ... lance.html (http://hbd.org/clubs/franklin/public_html/docs/balance.html)
I do not use Nitrogen so I do not have the calculations for it.

[Tankard]

Hmmm, my tap is 8 inches above the keg. I have 12 feet of 3/16 line.

(12*2.7) + (2/3 * 0.5) = 32.73333333333333333333333333

Apparently I need a length of beer line around 4.3 feet to get a PSI of 12. Doesn't this seem really short?

Also, do I measure the height from the disconnect to the shank?

[Ó Flannagáin]

4.3 feet sounds about right, mine are both around 4 or 5 feet

[MrMarbleHead]

Just cut it five feet, start with a pressure of zero in the kegs and slowly turn it up till you get a nice pour.

[mr x]

I'm of a different opinion. I like my 10 foot line length. It's a nice compromise that works for hefe's and highly carbed Belgians (I might even go 12 feet). It just pours a little slower for stouts and milds, but that's OK with me.

[mr x]

I'm of a different opinion. I like my 10 foot line, and may even go 12. It's a good length that works for hefes to stouts. I think it's better to start long than start short.

[DrunkenSatyr]

Do what works best for you. Mine was only an example. 12 psi is what I serve at so the calculation is tailored to my rig. The math is the same, just decide what your optimal carb level is then adjust.

[Tankard]

I'm getting a ton of foam now. I think my beer may be overcarbed. I have to set the PSI down to 4 now and I still get a 1" head of foam on each pint. Should I just keep bleeding off pressure until my beer is less carbonated?

[Shenanigans]

Doesn't WOP have some patient pending anti foam device?

[Peteoz77]

I thought you said you had this worked out Tank?

[mr x]

I'm getting a ton of foam now. I think my beer may be overcarbed. I have to set the PSI down to 4 now and I still get a 1" head of foam on each pint. Should I just keep bleeding off pressure until my beer is less carbonated?I thought you were going to put in a longer piece. What you are doing now will only make the problem worse until you have a flat beer. Get a 10-12 foot piece of beer line!

[MrMarbleHead]

Doesn't WOP have some patient pending anti foam device?

The flow gates won't work on over carbonated beer, only thing to do with that is let the keg warm up some and bleed presure off.

Tank do you notice that the beer is thinner and makes you burp more? seriously, though if the beer doesn't seem like the carb level has gone up in the actual beer it's self then i doubt it is over carbed.

I think that you running 4 PSI is about right for a 4 foot peer line like you got, I would take it up to at minimum a 6 or 7 foot length of line.

[Tankard]

It's just weird that I used DS's balancing formula and arrived at 4.5 feet. Flan and Pete say they use that length and have no problems.

[mr x]

There's a lot of give and take in balancing a draft system. People have a lot of different experiences. But the one thing nobody ever has a problem with is starting with a longer line, and then trimming it down if necessary. 4.5 feet will definitely not work for me at 15 psi. 10 feet minimum. Start long and go short if you have to.

[Jester369]

Another vote for 10 feet - it may pour a little slower, but you won't get any foaming. Backing down the pressure will just give you lower carbonation (eventually). Set the CO2 volumes to style/desired level and leave it, and adjust the line length as required to get the pour you like.

[MrMarbleHead]

It's just weird that I used DS's balancing formula and arrived at 4.5 feet. Flan and Pete say they use that length and have no problems.

Did you factor in the hight of your taps above the top of the keg? In theory that would raise your serving pressure due to the added resistance, but you never know.

You have to remember also that Flan and Pete are using different types of kegerators, they have upright fridges that have been converted. Like myself, My taps are at the same hight as the tops of my kegs. I have 5 foot of 3/16 beer line and run about 7-8 pounds for my standard beers.

[Tankard]

Yeah, I factored in the height above my keg.

I think I may have screwed up the carbonation level. For this beer, I wanted about 2.4 volumes of CO2 at 39 degrees. Using a few online calculators, it says I need 10.2 PSI. I carbed this thing at 12-13 PSI, and I balanced my system at the 12 PSI level. I'm not sure if this has any effect.

I think I'll order a 10 foot line with my next order, just to try it out. It's going to suck removing the existing line though, it was a tight fit.

[Redweasel]

Like some of the others said I replaced my lines with ten foot sections. No foam issues at all. Beer does pour a bit slower but that's not a big issue for me. It actually makes filling bottles easier.

[DrunkenSatyr]

Also, regulators are notoriously inaccurate ;)

[Tankard]

I was watching the inside of my keezer today while I was pouring a pint. It looks like an air bubble forms right above the beer out disconnect right after I turn off the faucet. The beer line starts gathering foam right near the end of the shank when the faucet is turned off. Then, when I open the faucet, that foam comes out first, followed by clear beer, and then another little amount of foam follows until it finally goes clear for good.

[Peteoz77]

Overcarbed

[mr x]

Serving pressure is too low for the pressure the beer is carbed at. That doesn't necessarily mean the beer is overcarbed, it's just out of balance.

[Peteoz77]

He was serving at 4-15PSI, if it's out of balance at all of those pressures, it's overcarbed,

[mr x]

It's not overcarbed if you're target for CO2 volume puts you at 13 psi for carbing, and then you try to serve it at 4 psi. That's not overcarbed, it's unbalanced, and it will guarantee to blow foam.

[Tankard]

I got the PSI at about 8 right now, and it pours well with the exception of the very first pour. It runs clear for a brief second, then spits out an inch and a half of foam, and then the rest goes clear. Even after I turn the faucet off, and let it set for a while, it pours great when I go for another pint. I tried putting the regulator at 10, and it still pours decent, but it's better at 8 or 9.

I looked inside the keezer and I notice that I am getting tiny bubbles near the end of the shank. They are forming in the beer line itself. I moved my beer line around in the keezer the other day because I noticed that there was a spot in the line where the beer wouldn't rest while the faucet was closed, almost like a big air pocket. That seems to have gone away, but I am still getting these bubbles near the shank. Any theories on why these are forming there?

[mr x]

If gas is coming out of solution, then the serving pressure is too low for your carbonation target. In other words, if you want the bubbles to go away, you will need to increase the serving pressure, or lower your CO2 volume for your keg. You may not be able to get rid of a slight nit of bubbling if it's coming out of the shank, because that is probably a bit warmer than the rest of the system.

[mr x]

Some good info:

http://draughtquality.org/

[evolutionfxr]

Monster Magnet rocks!!

[mordantly]

He was serving at 4-15PSI, if it's out of balance at all of those pressures, it's overcarbed,

spoken like a true rocket surgeon!


i use (x3) 6' .1875ID, a cobra, 12psi, 40F and have ZERO head factor!