force carbonating

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Aug 25, 2007
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Morrisville, NC
I am going to be force carbonating my first keg today. I have kegged a few others with corn sugar, and they turned out a little flat. My LHBS suggested force carbonating. I bought new O rings, and some keg lube to prevent unwanted leaks. Anyone have any suggestions for me? I'll probably hit it with 30 psi for 7 days. Is this correct?
Nope. That'll leave you overcarbed if left at a constant 30 for a week. Here's a chart for you.

Good luck,
What you CAN do is crank it up to 30psi and rock the keg back and forth on your knees for 10 minutes. This agitation will very quickly put the CO2 into solution with the beer. Then crank the reg back down to serving pressure and let set for a day or two so the sediment can settle out. Beer should be nicely carbed at this time to whatever volume you picked.
you CAN do that in a pinch, but if you want very nice, evenly carb'd beer, set it at serving psi for up to 14 days.

for me, that's about 10-12psi. the trick to kegs is always have at least one full one, so you don't have to fudge with rapid force carbing at 30psi when your keg runs dry.
JimC said:
What you CAN do is crank it up to 30psi and rock the keg back and forth on your knees for 10 minutes.
If you do that for 10 minutes you are going to end up with some very overcarbed beer.

I have carbonated nearly all my kegs of beer with the crank-and-shake method, and it works just fine if you do it right. I've only got a 2-keg kegerator and no secondary CO2 tank/regulator, so the slow methods of force carbing aren't practical for me. The key is to get a 'system' so you can get consistent results. If you crank to 30PSI and lay the keg across your lap, gently rock it back and forth, about once a second or so. Count up each time you rock it. Depending on the beer temp and how you rock it, you may need to count to somewhere around 70-100; you'll figure out the right value with some experience.

Personally, I intentionally stop short of where I expect it to be fully carbed, and then crank it back down to serving pressure and it will finish carbing at serving pressure within a few days - but will be carbed enough to be drinkable immediately.
I've tried all the methods and have settled on two that work perfect for me.

1) The ole standbye...set it at 10-12 and forget about it for 10 days.

2) Set it to 35 PSI for 36 hours (no shaking...just set it). Then shut off valve, bleed pressure and set back down to 10 PSI. If it isn't fuly carb'd, it will be within another 12 hours or so.

The time will vary slightly based on how "thick" the beer is. My Blondes and Helles can ge fully carb'd in 36 hours. My Octoberfests and heavier malty beer take maybe another 8-10hours at the 35PSI.

All my kegs charge at 35 degrees F.

The beer on the left is a light Pale Ale and just finished 36 hours at 35PSI.

Dycokac said:
So, chill the keg and then set the pressure, or will it work if you just presurize it outside the keggerator?
The keg needs to be cold.
My total time estimates begin from the time I place the keg into the chiller.

Trying to force carb a warm keg requires substantially higher pressures. Cold beer absorbs CO2 much easier.