Balancing my keg system.

Ok, so I'm having some foaming issues so I went online and did a little research on balancing a keg system.

My system is using 6' 3/16" tubing which should provide 18PSI resistance and has a vertical from bottom of keg to tap of 3' which should provide another 1.5PSI. I'm not sure about the shank, so we will leave that out for now. You also need to add 1PSI for every 2000' above sea level, which im about 600' so we will say 0.25PSI. That comes out to 19.75PSI, but to get my 2.6 Volumes of Co2 in my beer at 43deg I need 15PSI. The result is a 4.75PSI pressure difference and A LOT of foam. So I'm thinking to fix this I need to reduce my line length to 4'5" which should give me closer to 15PSI resistance.

The question is, does this sound right? Is it going to fix my foam problem? Does the shank add any appreciable resistance?

Thanks

Having too much line resistence shouldn't produce foam but rather a slow pour. How did you originally carbonate this keg? You might have more than 2.6 volumes if you did any of the accelerated carbing techniques.

OK, I was thinking that might be the case. No I just put it in there and leave it on 15PSI to carb the kegs. I have turned it down to 10PSI and been venting the kegs every now and then and gonna see if that helps, but I figure then Im gonna have some flat beer.

I'm sure someone will correct me because I'm wrong, but I thought 3/16" beer line had a resistance of 2 PSI? That's what I based mine off of. Five feet lines, 39 degrees, 10 PSI.

I'm in the same social club as the owner of a fairly large beverage distribution and after talking with him about my draft project he said that the most common cause of foaming was having the beer too warm. Just FYI.

The 2 psi per foot pressure drop for 3/16" ID tubing is just a rule of thumb. The higher the level of carbonation the lower the effective pressure drop will be. You just can't take the pressure, divide by two and get an exact length that will work. The rule of thumb will get you close though.

Just make all your tubing lengths for the highest level of carbonation that you will expect to brew. Then any lower carb'd beers on that line will just pour slower. FWIW, even if you put 200' of line on a tap you will still get beer to pour out the end, but it will be very slow.

I went into the archives and found a post that I made some time ago about balancing beers of differing levels of CO2. Here it is for your viewing pleasure:

I serve through 10' of tubing regardless of the style being served. The only thing that changes with the serving pressure is the pour rate. A Hefe served at 18 psi has a pour rate that is faster than a stout served at 8 psi. Both will serve foam free though, that is the goal!

It really is a game of compromise. Choose a length of line that gives you the flexibility to serve higher carbed beers and the trade off will be that when you serve lower carbed beers your pour rate will be a little slower. I have not found this to be a problem.

There is a rule of thumb that each foot of 3/16" ID beverage line has a pressure drop of 2 psi. That is a little simplistic. There is a large set of variables involved in balancing your system. The higher the carbonation level - the slower you want the pour. The faster the pour the quicker the co² will be knocked out of solution during the pour.

The rule of thumb that I use is:


Carb level = Desired Pour rate = Effective 3/16" Line Resistance at that given volume of CO2

1.8 to 2.3 volumes = 110-120 oz/min = 2.19 lbs/ft
2.4 to 2.6 volumes = 100-115 oz/min = 1.81 lbs/ft
2.6 to 2.8 volumes = 90-105 oz/min = 1.40 lbs/ft
2.8 to 3.0 volumes = 75-85 oz/min = 0.94 lbs/ft

So you can see that just using the 2 psi per foot pressure drop figure for 3/16" ID beverage tubing to balance your system does not take all factors into consideration.

OK well if you go with 2psi rather then 3psi, that would change my resistance from 19.75 to 13.75, which if I'm dispencencing at 15PSI I guess could be the issue. Like I said I have had it at 10psi for a bit and will try and see how it pour tomorrow. I might also knock the temp down to 39 or so and shoot for 13PSI and see if that makes a difference.

Actually, 2.6 volumes of CO2 reduces the effective pressure drop of 3/16" ID beverage tubing to around 1.4 psi/ft. At 15 psi that would require approximately 10.7 ft to balance out.

Like I stated in my previous post, it's best to select a line length that will balance out the highest carb'd styles of beer that you will brew. Then when you put a lower carb'd style of beer on that line the only thing that will change is the rate of pour.

Hmm, I'm tempted put about 15' on each one and be done with it.

evandam said:

Hmm, I'm tempted put about 15' on each one and be done with it.

Click to expand...

Mine are 8' and I set at 15PSI...and live at almost 6000' elevation. It seems to work ok.

I subscribed to Bobby's method of longer beer line and lower pressure rather than try to figure out the exact hose length and PSI to calculate a perfectly balanced system. I have it tuned in close to what the formula [see below] says, but if its OFF, I error on the side of a longer hose. The only drawback, if it really is one, is just a slower pour. Better than the alternative of fast pours and foamy beer.

I'm in no hurry to pour 8 beers a minute. I don't have a mob of angry patrons waving dollar bills at me...usually. So i don't have to worry about how fast I can pour a pint.

Here is a good thread on the topic:
https://www.homebrewtalk.com/showthread.php?t=73328


Attn Mod: Move to Kegging forum ??

**************
L = P - (H * .5) - 1
R

where

* L = length of beer line in feet
* P = pressure set on regulator gauge
* H = Total height from the center of the keg to faucet in feet
* R = Resistance of line from the following Resistance Table
* 1 = this is the residual pressure remaining at the faucet *

10' of line serves me well on all five faucets. I'm planning on experimenting with 3-4 feet of 1/8" ID tubing as well.

Hi everyone, I ‘ve been trying to figure out a solution in proper balancing my draft system and would like your advice on this. I am aware of the formula to calculate proper beer length line to get a good pour but the problem for me is that because I am using a bench dispenser (it has a built-in compressor) with an internal set length of 46 ft. / I.D. 5/16” , I cannot change that! My keg is at 40 psi at 68F and the dispenser sits 3 ft. over the keg.

I wish to adjust the pressure so that I get a good pour whiteout reducing the co2 levels in the keg (Bavarian wheat beer).

So by my calculations, in order to match the beer length that I have, I have to set the pressure at around 20 psi (20 psi / 0.4 psi/ft) = 50 ft. of beer line, but doesn’t that mean that over time the beer’s co2 level will be reduced to 20 psi from 40 psi where it’s now?

Best Regards,



John

Nice old thread...anyway, not sure how you come to that conclusion(not saying your wrong either), but if you really need 50ft to get it dispensed the way you want, i'd go with one of these, I have one and like it.

https://www.morebeer.com/products/inline-flow-control-compensator.html

Dland said:

Nice old thread...anyway, not sure how you come to that conclusion(not saying your wrong either), but if you really need 50ft to get it dispensed the way you want, i'd go with one of these, I have one and like it.

https://www.morebeer.com/products/inline-flow-control-compensator.html

Click to expand...

Thank you DLAND! I am attaching the dispenser I have connected to the KEG in case it helps, if you notice on the right side of the faucets there is flow control valve (which I almost have to keep restricted in order not to have excessive foam and it does take a minute to fill a glass). Is the inline compensator valve you sent me the same thing? Regarding the calculation I kind of reversed the formula in the sense that since I know what my set beer line length is (46 ft. ) of I.D. 5/16" I tried to come up with a PSI setting for the gauge to overcome this resistance (0.40 psi/ft), therefore 20 psi divided by 0.40 produces a result of 50 ft. beer line (which is what I have).

When you are looking to come up with the beer line that you need, using the formulas is relatively easy to come up with the length required! My case is the opposite (I have a set beer line length that I cannot change), so I am trying to figure what would be the proper psi setting based on the the keg's pressure (40 PSI at 68F) without losing beer co2 from the 40 psi and being able to pour at a regular speed without foam issues.