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Dancing Camel
08-03-2005, 12:41 AM
I have a few homebrew-sized batches that I am trying to force-carbonate in Corny kegs. The beer is at app. 36 deg F, and I've got it sitting on 45 PSI for about 3 days. Twice a day I shake the daylights out of the kegs for about 3 minutes. I still can't seem to get CO2 to dissolve into the beer. Other particulars - I do not have a carb stone, I connected gas to beer out line to push gas from the bottom and I've tested kegs for leaks. ANY IDEAS GREATLY APPRECIATED (I've got a festival coming up and flat beer would not be well received).

David

PS - It's a Wit beer in case that matters.

Rosie
08-03-2005, 04:09 AM
David,

Hmmm, I do a similar procedure without problems here. I force from the gas in without any issues - just a couple days at 30psi is enough.

A couple things to check...not trying to insult you here, just some things that spring to mind.

* Are you sure you are getting CO2 into the keg? e.g after bringing to 45 psi and you pull the release, you will know if you have 45 in the keg.
* Are you sure your regulator is calibrated correctly?
* Are you using an liquid out fitting on your CO2 line as the disconnects are ever so slightly different - again, could prevent you getting CO2 in the keg.
* Leaks can be detected by spraying some soapy water on a 45 psi keg. Lids sometimes don't seat properly, this can be remedied with some food grade lubricant on the o ring. I've had leaking posts has well...sometimes from forgetting to tighten the post completely. You could also be leaking from the poppet valve in the post. However, I would think at 45psi any of these things would be obvious....hmmmm

Good luck!

Rosie

Sir Brewsalot
08-03-2005, 05:53 AM
David,
As Rosie says, it should be obvious as to whether the CO2 is going in... you should HEAR the tank/regulator release the gas.

When I have this problem it's usually because the fitting isn't all the way (clicked) onto the keg.

Change any parts out lately?
Scott

Dancing Camel
08-03-2005, 07:39 AM
Thanks guys. I should make clear that CO2 is getting into the keg (I do hear it going in when I shake the keg). I also know it's in there because I just tapped 3 pints of the most delicious looking head you'll ever see. The problem is that the CO2 is not getting absorbed into the beer - the 1" of beer underneath the 7" of head is flat!

One thing I thought of - when I filled the kegs, I daisy-chained several kegs together in a closed line; when one was filled, the overflow went into the second until that was filled, etc. Consequently, none of the kegs had any headspace in them. Could that be the problem - that it needs surface area for the CO2 to go into solution? I'm clearly not a physicist so if this has nothing to do with it, are there any other ideas out there?

Almost desparate,

David

Sir Brewsalot
08-03-2005, 08:39 AM
David,

Lack of headspace definitely hinders the ability to get CO2 into solution, but I think you may have the OPPOSITE problem. The beer is OVERcarbonated. Once the beer is loaded with CO2 at pressure and you release that pressure, it comes "out of solution", and you get a nice creamy head. This is how is SHOULD work.

If you SATURATE the beer w/ too much CO2 as you have done, when you pull the pressure off of it (draw a pint), it not only puts a head on it, but kicks off a chain-reaction in the liquid that drives nearly all of the CO2 out of the beer, and it "foams out".

Solution: bleed ALL the excess gas off of the cold keg, shake the keg a bit to knock some CO2 out of solution (this will also pressurize the keg), and then serve a pint. If it's still not good, continue the bleed-shake-test cycle until you've got it right, or until you pass out from "over testing".

Next time: Get yourself a copy of a carbonation table to properly dial in your co2 pressure based on temperature of beer and desired carbonation level in "volumes of CO2". On average, you want about 2.5 volumes. I think there's a carbonation table on the Zahm website, but a Google seach will produce one... anybody have a link?

Let us know how it works.
Scott

Rosie
08-03-2005, 09:53 AM
I think Scott nailed it...the beer is probably over carbonated and all the CO2 is just jumping out of solution on dispense.

Fixing an overcarbonated keg can be done by continually bleeding off CO2 until you get to the desired level...

It may be that you are just trying to dispense at your 40 psi...which would also give you the same result, a pint of foam. If this is the case, just bleed all CO2 off, then bring up to 10psi for dispense - what I use for out of 5ft of beer line.

Here is one of the CO2 tables:

http://brewery.org/brewery/library/CO2charts.html

Cheers,

Dancing Camel
08-03-2005, 10:25 AM
Makes sense. I started bleeding off pressure - it will definitely take a while to get excess pressure out. Thanks again - I owe you both a beer.

David