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Set and forget carbing and temp

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snarf7

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Since this is my first time doing it I was going to use the more time consuming but less error prone method of setting it to desired PSI and leaving it for 2 weeks to stabilize.

I am using this chart for my calculations

My question is, will minor temperature fluctuations have much effect? I currently don't have a fridge setup to maintain constant temp so I was just going to use our cold cellar which is currently around 48 degrees. We're in the NE and the temps are slated to be stable and cold for the next 10 days at least. The cellar doesn't fluctuate much even between summer and winter (maybe 10-12 degrees?) so it should be fairly stable given the stable outdoor temp within +/- 2 probably. How should I approach this? Should I make daily PSI adjustments or what?
 

mongoose33

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Don't fool with daily adjustments. You need to figure out how many volumes of CO2 you want, consult the chart to see what pressure is needed to produce that at 48 degrees, then dial in that pressure on your regulator.

By the way, there is a way to speed that up without completely fast-force-carbing the keg. Set it at 36 psi for 20 hours, then dial down to whatever the chart says. It won't completely carb it to your target, but it'll get you maybe half to two-thirds there, then the "set and forget" method can complete it. No danger of overcarbing, but faster to having fully-carbed beer.

This is similar to my own situation. I close up my SS fermenter for the tail end of fermentation, and the beer self-carbs similarly to how bottle conditioning works. When I kegged that beer last night, the beer temp was 38 degrees, the pressure 7psi. That's not enough; I want about 2.5 volumes, so that means I set the regulator at 11psi, set and forget. It'll finish in less than half the time as starting from scratch, since I started with a partially-carbed keg.
 

william_shakes_beer

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By the way, there is a way to speed that up without completely fast-force-carbing the keg. Set it at 36 psi for 20 hours, then dial down to whatever the chart says. It won't completely carb it to your target, but it'll get you maybe half to two-thirds there, then the "set and forget" method can complete it. No danger of overcarbing, but faster to having fully-carbed beer.
I have 2 kegs serving plus an "on deck" keg carbing, so I have never done anything other than set at the desired serving pressure and leave it alone for a month or 12. Curious: If I set then keg at 36 psi for 20 hours, then dial it back to, say 12 psi, what prevents beer from pushing back through the gas line and fouling the pressure regulator? (assuming someone ignorantly chose to ignore common wisdom and fill the keg above the level of the gas tube, something we neeeeeeeever do ;) )
 

mongoose33

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I have 2 kegs serving plus an "on deck" keg carbing, so I have never done anything other than set at the desired serving pressure and leave it alone for a month or 12. Curious: If I set then keg at 36 psi for 20 hours, then dial it back to, say 12 psi, what prevents beer from pushing back through the gas line and fouling the pressure regulator? (assuming someone ignorantly chose to ignore common wisdom and fill the keg above the level of the gas tube, something we neeeeeeeever do ;) )
You simply relieve the pressure on the keg by pulling the PRV. If you don't have one, put a gas QD on the post and relieve the pressure that way.
 
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snarf7

snarf7

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By the way, there is a way to speed that up without completely fast-force-carbing the keg. Set it at 36 psi for 20 hours, then dial down to whatever the chart says. It won't completely carb it to your target, but it'll get you maybe half to two-thirds there, then the "set and forget" method can complete it. No danger of overcarbing, but faster to having fully-carbed beer.
OK I'm sold, I'll give that a whirl. So to recap though, I pressurize to 36 psi for 20 hrs, then drop it to 12 psi (or whatever the chart says for my temp) then I pull put the PRV on the coupler and wait until it stops hissing and then push it back in? Am I understanding this correctly?
 

mongoose33

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OK I'm sold, I'll give that a whirl. So to recap though, I pressurize to 36 psi for 20 hrs, then drop it to 12 psi (or whatever the chart says for my temp) then I pull put the PRV on the coupler and wait until it stops hissing and then push it back in? Am I understanding this correctly?
Let me just note that some of this depends on what you're trying to do in terms of volumes of CO2.

Do this: do 30psi for 20 hours. That should get you roughly 8-9 psi if you're doing it at 38 degrees or so.

Then, disconnect the gas line, pull the prv to vent the keg pressure. Dial down the regulator to what you want, then reconnect.
 
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snarf7

snarf7

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Let me just note that some of this depends on what you're trying to do in terms of volumes of CO2.

Do this: do 30psi for 20 hours. That should get you roughly 8-9 psi if you're doing it at 38 degrees or so.

Then, disconnect the gas line, pull the prv to vent the keg pressure. Dial down the regulator to what you want, then reconnect.

OK so do I understand this correctly? By cranking it up to 30 PSI for 20 hrs you're doing a quick 'force carb' such that the pressure is so high under that small volume that it forces the CO2 into the beer. So after 20 hrs or so that 8-9 psi is incorporated into the liquid now right? And pulling the PRV just vents the additional non-absorbed CO2 in the keg? Then you dial it in to 13 or whatever and it slowly comes up to correct pressure?
 

mongoose33

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OK so do I understand this correctly? By cranking it up to 30 PSI for 20 hrs you're doing a quick 'force carb' such that the pressure is so high under that small volume that it forces the CO2 into the beer. So after 20 hrs or so that 8-9 psi is incorporated into the liquid now right? And pulling the PRV just vents the additional non-absorbed CO2 in the keg? Then you dial it in to 13 or whatever and it slowly comes up to correct pressure?
Exactly.
 

Vale71

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If I set then keg at 36 psi for 20 hours, then dial it back to, say 12 psi, what prevents beer from pushing back through the gas line and fouling the pressure regulator? ;) )
The check valve in the regulator. Nearly all of them have a check valve to make sure gas can only flow outwards to prevent what you describe from happening. To verify, dial the pressure down and listen for the sound of gas being released. If you don't hear anything you're good to go.
 

balrog

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There is a burst carb sheet out there that I use that gets me close in my 60 degree basement with 30 psi 26 hrs, then 8-10psi serving pressure, 2.21 vols, but you have to know vol beer, and total vol of keg. It works pretty well. If I use 4.5gal in 5.25gal total keg, at 48 degrees, 30 psi for 20 hr puts in 2.23vol CO2. It's very touchy to beervol, kegvol.

Short story long, I know, but 30 psi for 20-24hr, then off, will get you close.
 

eric19312

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There is a burst carb sheet out there that I use that gets me close in my 60 degree basement with 30 psi 26 hrs, then 8-10psi serving pressure, 2.21 vols, but you have to know vol beer, and total vol of keg. It works pretty well. If I use 4.5gal in 5.25gal total keg, at 48 degrees, 30 psi for 20 hr puts in 2.23vol CO2. It's very touchy to beervol, kegvol.

Short story long, I know, but 30 psi for 20-24hr, then off, will get you close.
Would you post a link to this sheet?
 

balrog

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3 beers in but my Google fu is strong.
This was the article
This is the linked sheet

It's a little tricky to use. Put in what you know up top with volumes and temp. Up top, use what you'll be serving at eventually (that's what I do). THen then lower part uses the temps and volumes but put in the 30psi and tweak around with the hours of bursting to get the value of vols absorbed during the bursting phase.

That's what I do at least and it works pretty well.
 
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