Keg Carbonation advice

[techprof]

Lhbs said to carbonate most styles of beer, chill keg, set to 25 psi and in 3 days lower to 10 psi and its ready to go. I have a temp/Co2 volumes chart and nothing aligns with the advice.

Any thoughts?

 

[hvjackson]

The 25 psi period is just to jump-start the carbonation. You don't want to leave it at that level too long or it will over-carbonate.

As for the final pressure, it depends on what style of beer you're brewing and the temperature of the keg. You'll want to use a lower pressure for colder temps and a higher pressure for warmer temps to get the same level of carbonation. Typical values should be around 8-15 psi, hence the 10 psi rule of thumb from your LHBS.

To decide on the exact number, first pick a carbonation level (measured as "volumes of CO2") based on your preference and the beer style. Should usually be around 2 or 2.5. Then pick a serving temperature, again based on your preference and the beer style. Probably 35-55˚F. Then you go to the temp/CO2 chart and look up the PSI for that pair of numbers.

Example:
Style: Belgian White
Desired serving temp: 40 ˚F
Desired carbonation: 2.5 volumes
CO2 pressure: 12 psi (from table)

Any specific questions?

 

[techprof]

I was a bit confused because he said he doesn't bother with proper CO2 volumes. Thanks for the clarification.

 

[hvjackson]

Well as a practical matter you might decide that you don't care too much if the carbonation level is exactly correct for the style of beer. You might just want to leave your regulator at the same pressure from keg to keg, to avoid having to fiddle with it every time. This is especially true if you have a kegerator with a CO2 distributer for multiple kegs—you just have to pick a single pressure for all of them. 10 psi is a plausible number for typical refrigerator temps (high 30s F).

 

[day_trippr]

Or, you could figure out what you're doing and why.

You could do worse than to start with this page, which not only lists the typical volumes of CO2 for numerous beer styles, it will calculate the proper CO2 pressure to use to obtain any desired CO2 volume and beer temperature you plug in.

"Burst carbonation" schemes are highly volatile and the rate of failure is absolutely the inspiration for half of the threads in this particular forum...

Cheers!

 

[techprof]

Switching from 4ft 1/4in Id beer line to 8ft 3/16in resolves any pouring problems with 10psi @36f