Dispensing pressure SAME as carbonating pressure?

[Kazi the Younger]

I read this from one of the great links that Bugeater posted on Kegging:

http://www.shagg.net/brewing/?p=10
"Dispensing Pressure: Once you have carbonated your beer, the second part of having a balanced system is to set the correct dispensing pressure. To achieve the best results, use the same pressure that you found in the carbonation step as your dispensing pressure. Some instructions recommend that you set a lower/higher dispensing pressure and turn the gas on/off each time you pour a beer. This is usually a sign of not having a balanced system, and you need to continuously tweak the pressure in an attempt to “chase” the proper balance. In a correct setup, you should never need to adjust your dispensing pressure, or even turn it off. Set your regulator to the right pressure and leave it turned on all the time. The same pressure is used to dispense the beer as well as to maintain the correct carbonation if the two are equal."

This makes sense to me, yet, I have heard so many homebrewers talk about shutting off pressure, turning it on at a lower setting, dialing it up, etc. I don't have practical experience with it yet, and I know it will probably take some experimenting to get it right. Have you guys found this to be correct? Keep the two pressures the same, and just make sure you cut your beer lines to the right length?

Serving line Pressure:
"In most cases, the best tubing to use is 3/16″ food grade (or beverage) tubing. The common resistance rating for 3/16″ tubing is 2 PSI/foot. You want to use enough tubing so that you (theoretically) end up with 0 PSI at the tap."

"For example, if you are serving beer at 40F and want it carbonated to 2.5 volumes (typical for US beer), then you’ll find by looking at one of the various charts that you need 12 PSI to achieve the right carbonation level. Then, you will set your dispensing pressure to 12 PSI and leave it connected to the keg with the gas turned on. Finally, since you are using 12 PSI of dispensing pressure and 3/16″ tubing is rated at 2 PSI/foot, you will need 6 feet of serving line in order to balance it out to 0 PSI at the tap."

Do you find this to be correct?

[Mylo]

Yes. Keep your kegs at the proper temp and pressure for the desired volumes of C02 - and balance your system to ensure a good pour. I have a few friends that practice the "turn off the gas an occasionally correct the low pressure in the keg" thing. Seems like a lot of fussing - with variable results. With a balanced system (and no leaks) - the beer is always the right level of carbonation and it pours fine. I keep a couple of extra long lines in my kegerator that I use for my belgians.


Mylo

[Brew Engineer]

One of those links also gives examples and formulas, that even take into account hight from keg. If your tap was 10 feet above the keg, versus 1 foot.

But, yes, I try to keep my serving pressure at my carbonating pressure and balance my lines. That being said, I also tend to keep my tank turned off when I'm not using the kegs for a while. I had one small leak that I missed once, and went through a CO2 canister in about a week.

But I like to keep my serving pressure about 10-11 psi, and calculate my carbonation levels and temperatures based on that psi. Then I shoot for the middle road and fudge it a little, because I have one fridge, set at one tempreature, and two different beers on tap.

But the moral I'm trying to convey, is to start with a balanced system. It will allow you to fudge it a little in either direction, but it gives you a solid starting point for line lengths, and serving preessures.

[Kazi the Younger]

Thanks guys...one more thing.

Lets say you have two beers that require vastly different carbonation levels--say a Saison and an english bitter. Problem is, times are tough and you can only afford one regulator.

CAn you: Carbonate one beer to its respective level, then remove the gas and then carbonate the other beer
to it's respective level? When you go to serve, can you hook up the gas to one keg and set the serving pressure to where it needs to be for style, then once the keg is kicked, hook it up to the other keg, and set it to that level, and serve it?

Sorry if these are dumb questions. If I had unlimited resources I would buy a manifold where I can dial in separate pressures, etc on separate taps.

[Mylo]

Of course you can. Rome (and your kegerator) wasn't built in a day.


Mylo

[Kazi the Younger]

Hey, well that's great--Glad to hear you can carbonate a beer, disconnect the gas, then hook it up again and serve it later.

Another stupid question: How long will a beer stay carbonated in a keg after the gas is disconnected? I'm assuming I should keep it cold.

Ideally, I'd like to brew several beers, have them all kegged and carbonated, then have the ability to store them, bottle them, and serve them immediately, or at later dates. So how long can a beer stay off the gasline without losing carbonation?

[Mylo]

If you have leaks.... less than a week. How long does a can or bottle of beer stay carbonated, once they cap it off? Come on, brotha...

You should keep it cold because it will last longer - not because of carbonation.


Mylo