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Cold Crashing in Carboy

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Rob2010SS

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So I'm going to attempt cold crashing for the first time in my 6 gal glass carboy before transferring to keg. I have a few questions...

1. I've read about 2 different methods of doing this - switch out the airlock to an S type airlock or remove the airlock and cover with sanitized foil. Are these both acceptable methods to use or is one better than the other? I've read that the only thing to watch out for going to the S type airlock is to make sure that you don't fill it any more than what one of the "bubbles" can hold...

2. I'm also going to be using gelatin in this one. I've read of people using the gelatin right before cold crashing but then I've also heard of people chilling the beer down to ~50*F, then adding the gelatin, then crashing to 32*F. Is one of these methods better than the other? Is the chilling to 50*F first just a waste of time?

Thanks for the help.
:rockin::rockin::rockin::rockin::rockin::rockin::rockin::rockin::rockin:
 
I've always dumped most of the liquid from my air lock so that there isn't much to "suck back". If I still have my blow off tube connected, I make sure that there isn't much liquid in the blow off container, so nothing sucks back.

As for cold crashing, I always drop the temp to 34 deg. for at least 24 hours before adding gelatin. Then keep it there for at least another 24 before kegging.
 
Most airlocks have a 'max fill' line printed on them. Just fill to there and you won't get any liquid suck back problems.

On the S type airlocks this is equivalent to filling one side all the way (or slightly under). When the pressure is equal on both sides, each chamber will have half of the liquid (which is where the 'max fill' is set to).

Cheers!
 
Most airlocks have a 'max fill' line printed on them. Just fill to there and you won't get any liquid suck back problems.

On the S type airlocks this is equivalent to filling one side all the way (or slightly under). When the pressure is equal on both sides, each chamber will have half of the liquid (which is where the 'max fill' is set to).

Cheers!

But with the 3 pc, you can't do that because it's designed to prevent suckback, correct? That floating piece will just get sucked down and pose a problem I think.... Whereas the S type will allow a bit of suckback without putting sanitizer in the beer, from what I've read.

Perhaps sanitized foil is just easier?
 
ime it's totally a myth that a 3-pc lock won't suck back.
otoh, a properly filled S-lock can't.
foil will work but make it tight enough to keep out fruit flies...

Cheers!
 
Just going by HBT posts it clearly happens.
If the wee bastids are about, I expect one could follow its nose when the door is open and you'd never be aware.
A rubber-banded chunk of foil isn't going to be gas-tight but it ought to keep the wildlife out...

Cheers!
 
I've always used a 3 piece with vodka in it. Then I don't really care if there's a bit of it sucked in. No issues so far.

My routine is blowoff until the first dry hop. At that time I switch to the three piece filled with vodka, then I can just drop the temp on the inkbird when I'm ready to cold crash.
 
But with the 3 pc, you can't do that because it's designed to prevent suckback, correct? That floating piece will just get sucked down and pose a problem I think.... Whereas the S type will allow a bit of suckback without putting sanitizer in the beer, from what I've read.

I've definitely had suck back with the 3 pc.
I wasn't paying attention once, filled the 3 pc up to high. Came back the next morning and a good portion of the liquid had gone missing and the remaining was sucked up into the central area. So, I can only assume some of the liquid had gone into the fermenter.
I wasn't worried though because I use vodka in my airlocks (though honestly star san wouldn't hurt either in those small volumes).

I do prefer the S type though when cold crashing. They are just easier.
 
S-Type seems to be the ticket as the volume (50% of the chambers) will allow it to work in both directions.

Regarding those fruit flies... Little bastards can also trace down the line used for the thermostat from the InkBird? Maybe... Saw a few around the latest batch so not sure if it was some drips on the garage floor or if they were after the motherload in the Danby...
 
While I agree the S style will not allow the liquid to be sucked in, I do believe they will allow oxygen to get sucked through.

I ferment and cold crash in plastic Fermonsters. I went and bought a valve that I added 2 hose barbs to. One is tightly jammed in my stopper, and I run the other to my CO2 regulator. I keep the valve closed. If I check it and the fermenter is starting to suck in a bit, I open the valve an push a little CO2 in until the vessel comes back. I check it often when starting the cold crash, but one the temp settles, they've been fine. Has worked like a charm over a handful of batches.
 
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