Cold Crashing in Keg Fermenter - Do I need to worry about negative pressure?

[Knightshade]

I've fermented my last 2 batches in a 6G Torpedo. Prior to using this, I was using a Fermonster which as I'm sure some of you are familiar will start to suck in on itself if you haven't hooked up a mylar balloon, cold crash guardian or something else to counteract the negative pressure.

I would just cold crash a little slower, pump in some CO2 via the ball lock, rinse repeat.

Now..a keg isn't going to suck in on itself, or at least I'm assuming the negative pressure won't be enough where it would be an issue. So do I need to hook up some CO2 every once in awhile for any reason? I did it with my last batch and when I racked it, it was slightly carbonated. Which I didn't have an issue with, but it was completely unintentional so I'd like to avoid it.

 

[day_trippr]

Cornelius kegs are designed to hold positive pressure therein, not a vacuum, so there's a non-zero chance the lid could get sucked down ever so slightly but enough to equalize the pressure inside...

Cheers!

 

[burtom]

If the keg is not leaking just make sure your pressure is above approximately 5 PSI when you start your cold crash. I normally start cold crash at about 10 PSI. That will be enough pressure to not draw a vacuum in the keg. If it is leaking you probably aren't going to draw a vacuum anyway.

 

[odie]

If you are keg fermenting you should have some pressure like 5-10 PSI or more. cold crashing is not going to result in negative PSI unless you are starting with almost no pressure.