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Line Balancing Confusion

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dirtymartini

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I'm a little confused about line balancing/regulator pressure. I have a kegerator with a two draft tower; IPA on one line and and an ESB on the other. I'm getting way to much foam when I pour either one. I have my regulator set at 13 psi with approx 6.5 feet of 3/16 line. Temp around 38 degrees.

I have been trying to read up on balancing and it seems to me to have right CO2 volume in the beer I should have the regulator set where it is, but I think I need to shorten the beer lines....Am I on the right track?
 

mr x

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I think you may need to go the other way and lengthen the lines. There are a number of threads on this issue. Search around and good luck.
 

Bobby_M

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Since you mentioned a tower, I'd actually expect you to be quite balanced right now. However, I'd start looking at two things. One, is the gauge accurate. You might be sitting at 16psi if the gauge is a little off. I replaced all my older 0-30 gauges with 0-15. I had a lot better success.

I'd also ask how you carbed these kegs. Priming sugar, hightened pressure with shaking, long term at 12psi? They could be overcarbed. Vent the kegs a bit but leave the pressure where it is.
 

Bearcat Brewmeister

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I think the line length is too long and the pressure is too high. If you dont have separate regulators for each beer, I would use 7psi with about 2 feet of line at 38F (depending on a few other variables, but this is correct within 1 psi and a few inches of line).

In the software forum, I posted an Excel Line Balancer based on many calculation sites on the web and my fluid mechanics book that does line balancing for you. I have never had an issue since using it. The one thing to make sure you do with beer line is to make sure it is always rising from the beer out post on the keg to the tap - no dips. Dips in the line can cause foaming issues.
 
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dirtymartini

dirtymartini

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Bearcat Brewmeister said:
I think the line length is too long and the pressure is too high. If you dont have separate regulators for each beer, I would use 7psi with about 2 feet of line at 38F (depending on a few other variables, but this is correct within 1 psi and a few inches of line).

In the software forum, I posted an Excel Line Balancer based on many calculation sites on the web and my fluid mechanics book that does line balancing for you. I have never had an issue since using it. The one thing to make sure you do with beer line is to make sure it is always rising from the beer out post on the keg to the tap - no dips. Dips in the line can cause foaming issues.
Thanks, I actually found your excel sheet through the sticky at the beginning of this forum. Yours and a couple of others I read made me think the line was too long. After all, the longer the line the more resistance resulting in a higher pressure at the faucet correct?
 

mr x

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No, the longer the line, the greater the pressure drop, resulting in a lower pressure at the faucet. Personally, I think 10 feet is a good place to start. A longer line will only result in a longer pour.
 

Sea

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I get a perfect pour with 6 ft of 3/16 line, and a reg setting of 12PSI (2.5 vol) at 40 degrees F. I'm with bobby, try turning your reg down a bit.

Then again, it could be your tubing. Not all 3/16 ID has the sam Pressure drop per foot. The previous crap I had poured foamy with even 10 ft of line.
 
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dirtymartini

dirtymartini

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mr x said:
No, the longer the line, the greater the pressure drop, resulting in a lower pressure at the faucet. Personally, I think 10 feet is a good place to start. A longer line will only result in a longer pour.

Here is the info that has me thinking the lines were too long...this is pretty close to what I have except right now my beer lines are longer than what is recommended here.

Example 1
Faucet is 2 ft above the center of the keg
Desired volumes of CO2 is 2.4
Temperature of keg is 40°F
We're using 3/16" id plastic beer line, with a pressure drop of 2.7 psi per ft.

Looking in the carbonation chart above, the regulator setting should be 11.2 psi for 2.4 volumes CO2.

The formula is:
L = P - (H * .5) - 1
R = 11.2 - (2 * .5) - 1
2.7 = 11.2 - 2
2.7 = 9.2
2.7 = 3.41 ft.


This means that a 3/16" line of 3 feet 5 inches will drop enough pressure so that the keg will stay at the desired carbonation level, yet the dispensing pressure will be low enough (around 1 psi) such that it will not foam.


Here is where I found the info...http://hbd.org/clubs/franklin/public_html/docs/balance.html
 

Bobby_M

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Lines that are too long will only make the pour take longer but it will NOT cause more foam. Suggesting that you shorten your lines when you have a foam problem is bad advice IMHO.

As I mentioned, I would be suspect of either your carbonation method which could have resulted in over carbonation or your gauge is reading low (meaning the pressure is really higher). You didn't mention how you carbed the kegs.

For what it's worth, I use 10 feet of 3/16" and vary between 10-13psi. The pour is perfect. On the one faucet I haven't lengthened the line on (it's still 5.5'), I get plenty of foam. My rise from center keg to faucet is only 16" though.

Are you using beverage grade 3/16" ID thickwall tubing or some home depot PVC stuff?
 

mr x

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Bobby_M said:
Lines that are too long will only make the pour take longer but it will NOT cause more foam. Suggesting that you shorten your lines when you have a foam problem is bad advice IMHO.
Exactly. I don't think many people have fixed a foaming problem by shortening the lines.

Are you getting gas coming out of solution in the lines? Do you have tower cooling?
 
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dirtymartini

dirtymartini

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Bobby_M said:
Lines that are too long will only make the pour take longer but it will NOT cause more foam. Suggesting that you shorten your lines when you have a foam problem is bad advice IMHO.

As I mentioned, I would be suspect of either your carbonation method which could have resulted in over carbonation or your gauge is reading low (meaning the pressure is really higher). You didn't mention how you carbed the kegs.

For what it's worth, I use 10 feet of 3/16" and vary between 10-13psi. The pour is perfect. On the one faucet I haven't lengthened the line on (it's still 5.5'), I get plenty of foam. My rise from center keg to faucet is only 16" though.

Are you using beverage grade 3/16" ID thickwall tubing or some home depot PVC stuff?
I'm using 3/16 beverage grade tubing. I bought the kegerator at my local HBS.
The rise from top of kegs to back of faucets is about 2'

The commercial beer foams the worst, Victory Hop Devil in a sixtel. The other beer is an ESB I primed in the keg with corn sugar.

I hope this helps...Thanks for all the help so far. I probably won't have it dialed in for the SB....but it won't stop me from trying!
 

mr x

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It takes time to work out the kinks. Took me a keg to get it completely right, but it wasn't wasted beer or time.:)

Good luck.
 

Sea

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If you want to drink your beer today, just turn the gas off, and pop the pressure relief valves on your kegs, and let them sit open for a little while, then close and check. Repeat if necessary.
 

Bobby_M

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The place to start for now is to turn the gas valves off. Purge all the pressure from both kegs (pull the release until the no more hiss). Turn your reg down to 10psi and open the valves. See how it pours. If it's a nice pour, consider leaving it at that pressure. If you start sensing a lowered carb level, then you can reevaluate the balance situation.

Anecdotally, the three low pressure gauges on my secondary reg read (-8, -3, and +2) from the actual pressure on the regs. Don't underestimate the possibility of the that one gauge being way off.
 

PeteOz77

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I had a similar issue not long ago while using 2 different size beer lines. One was 5mm, one was 6mm and I could NOT get them both to pour the same, 5mm was always foamy. I played with shortening the 5mm line and it got better, until the next keg.

I got the sh!ts and changed out the 5mm to 6mm of the exact same length, but still had a LOT of foam. Even after popping teh pressure valve for an hour, even 3psi, which barely came out the tap was a foamy mess. Turns out that the problem was a severely over carbed keg. I removed the gas line, flipped the pressure valve for 30 minutes, then flipped the pressure vavle back down. Nothing came out until I gave teh keg on quick shake.

Viola! beer coming out with a LOT less foam. I continued this process of serving until there was no pressure, then shaking the keg until it stopped serving (Still plenty of carbination in beer), just giving it a small shake every 4-5 beers. Once it wouldn't serve any more by shaking, Ihooked the gas back up and set it to serving pressure and all was good!
 

Bearcat Brewmeister

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Problem #1 - your keg is overcarbed so you need to release some pressure a few times. Since you don't have separate regulators for each beer and you have two beers which should have different carbonation, I would use aroung 2.1 volumes.

Problem #2 - your line is too long for 3/16" dia, 38F, and 2.1 volumes. Check my sheet, any other web site, or an engineering fluid mechanics book. For 2.1 volumes, you only need 7 psi with around 2 feet of line. Since you only want 1 psi left over at the tap, your line needs to scrub off the excess. If you use high pressure, you need longer line to get rid of that pressure. Bobby is right - that in itself will not cause foam, but it does two things. One, it makes your beer overcarbonated. At 13 psi, you have about 2.7 volumes, which IMO, is way too high for an ESB and fairly high for an IPA. Second, with longer line, you increase the chance that your line is not feeding up from the keg at all spots. Foam collects at high spots in the line. If the line feeds up at all times, that spot is at the tap, so air is the first thing out and you do not get foaming. If you have a local high spot further down your line, bubbles will form there. When you open the tap you get beer, bubbles, beer, and that causes foaming.

Another thing that causes foaming is temperature change, sometimes caused by warm taps. Is your tower cooled or insulated?

Your calculations show 3.4 feet of line. Three minor issues. One, you have to count your shank length in your tap. Two, you are at 38F instead of 40F and 2 degrees makes a difference of 1 to 1.5 psi and about half a foot of line. Three, you used 2.4 volumes, and I think that is a bit high - I would use 2.1 and that is a difference of over a foot of line and about 3.5 psi. That is where we differ on 3.4 feet of line compared to 2 feet of line.
 
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