Burst carbing


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Feb 6, 2013
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I'm planning to burst carb my fresh keg, so I'm starting it out at 30psi, then I'll move to 20 after 24 hours, then 10-12 after another 24 hours. My question is: do I need to release the pressure after I step it down, or does the excess CO2 just go into solution?
It will eventually equalize. However, I don't know what affect the residual pressure will do with the carbonation level. What I mean is I'm not sure how long it will last as I've never done a study on it. It could stay like that for a while, causing over carbonation, or it could drop fairly quickly. I suppose it would depend on the level of carbonation that the beer is already at. The higher the dissolved CO2 in the solution, the longer it will likely take.

I would think your best bet would be to do a quick purge of the pressure and continue on.

tl;dr: I don't know enough, just purge it.
You don't have to but you'll have to either disconnect the gas line and vent the line or if you have a shutoff after the gauge, shut that off and release the pressure to the gauge before resetting the pressure. Otherwise it'll be hard to get an accurate pressure read.
Okay, so do I shut off the valve after the regulator, then turn pressure down, then purge? Or shut valve, purge, decrease pressure?

I'm thinking it's first, since I'm setting it lower and then purging to ensure it stays at lower level.
first it really depends how cold the beer is as to how well it the co2 dissolves but, what I do is fource carb at 30 then unhook it and leave in the fridge at dispensing temperature unhooked for a couple of days, then vent it and hook up the co2 at 12 psi for a week, after 3 days take a sample, it will mostly be foam but let it settle then decide from there;

keep in mind since you will be putting allot of pressure on the beer some of the solids and yeast still in the beer will float to the bottom and come out in the first few glasses, that is by no means going to be the final taste of the beer
Although now I am thinking that if I shut off gas, lower pressure, and then open valve back up, I could get beer flowing back up the tube. Better to just lower the psi on regulator and then vent keg? SWMBO will actually be doing this, and she has no clue, so I'm trying to keep it as easy as possible.
Only way to get beer backflow is if you overfilled the keg, ie filled above the short gas in tube, or if you shake it and the foam is that high. I force carb all the time and have blown foam or beer back if I forget to purge. If you have multiple kegs on the same system this gets complicated but as a rule I try to allways remember to purge keg before reducing pressure to avoid any backflow possibility.