draft beer line question

[FLHEURB]

I'm calculating size and length of beer line required for a draft system. Due to the nature of the system, I will need to run my beer line up from the keg a few inches, then down to the ground, run it some length, and then back up to my tap, which will be about 5' up from the ground. I believe a normal system will simply be from the keg up, the line never going below the top (or at least center) of the keg. How will going below the center of the keg affect my calculations? Do I simply use the sum of all vertical measurements? Do I have to take something else into account or change my constant for vertical length (which is .5, I've read)? Thanks all!

Mike

 

[GeauxBrew]

You're correct, head pressure is roughly .5 psi per foot regardless of how many times your line changes direction. But don't forget the length of your beer line also makes a difference in the balance of your system. Depending on the ID of your line, I'm not sure off the top of my head but for 3/16 line I think it is about .2 psi per foot.

What pressure is your regulator set, How far above the center of your keg is your tap, and how long is your line?

Also how much of that line is outside of your kegerator? As beer flows through, it'll warm up and might cause some execesive foam.

 

[FLHEURB]

I'm calculating it out like so at the moment (some things being roundabout numbers and not exact):

(4.5' X .5) + (2 X 1) + (15 X .7) = 14.75
keg center to tap 1/4" od ss beer line 1/4" id beer line

The height calc would add another 1 psi if I add the length going down to the ground and back up (1' down and 1' up from center of keg). 15.75 seems a little high, but I've seen conflicting numbers in this regard, but I've read between 12 and 19 is ok. The keg will likely be around 40-42 degrees. And unfortunately, though insulated, the line will be out of a refrigerated state for the 15 feet. I figure I'll have to deal with that in some way, but it's the only way I can go as this is for a portable camping bar.

Any feedback on this would be great. Thanks.

 

[Bobby_M]

The head pressure is calculated for total RISE, not the sum of all vertical movement. If you start at 4 feet off the floor and drop 4 feet and rise 5 feet. The difference is one foot and negligible. The line length has far more impact.

 

[FLHEURB]

Good to know. Thanks.