Originally Posted by Elisha8685
Wow, I didn't know this about the difference between homebrew lines and commercial. I cut mine based on the commercial equation and my beers come out with so much head I have to wait and pour 2-3 times for each pint. Time to order 10' lines!
There's no difference between the lines, since the beer line sold by most LHBS is the exact same stuff that's used in commercial systems. The main difference is serving temperature, and the fact that those calculators assume a constant figure for resistance, when it actually varies based on flow rate. Commercial systems are kept below 36°F, usually 33°-34°, as a measure to reduce "tainted" beer from infections growing in the dirty lines, or even in the kegs. "Ideal" flow for a bar is the fastest that the beer can be poured without excessive foam, since faster pours equal less waiting for customers and more beers poured per hour. At these temps, that usually means ~1gal/min flow rate, which is what the calculators shoot for. At warmer serving temps, like the ~40°F most of us homebrewers seem to like, the pour needs to be slightly slower to keep the CO2 in solution, which means slightly longer lines, and since the slower flow reduces the line resistance, that means even longer lines. As mentioned above, the only side effect of lines that are "too long" is a slightly slower pour, and since resistance reduces with flow, you can go with really long lines and still not see a huge difference in the time it takes to pour a beer. Since I'm not running a business where the number of pints I can pour in an hour impact my profit, a slower pour is fine. Extra long lines also give some leeway if you ever decide to serve a hefe or belgian at the customary 4.0+ vol of carbonation. I figure that if I have time to drink a beer, I also have a few extra seconds to wait for it to pour.