First cold crash upcoming - suck back questions

[TravelingLight]

Never done a cold crash before. Probably because I didn't think I had a means to do it. Well, I just figured out my carboy fits perfectly in my kegerator. So the beer I have finishing now will be cold crashed and fined in the kegerator.

I've read a lot of threads on suck back and seen a lot of different methods but no real consensus. I have two air locks, one three piece and one S-shaped.

So what do I do for bung/air lock/blow off when I crash? Here are my options and potential issues I see with them. I'm looking for guidance on my best option.

Option 1: Use a solid bung instead of an airlock. This beer is fermenting out for two weeks, so I know fermentation is done. But should I worry about any problems with the bung getting sucked all the way back into the carboy?

Option 2: Use an air lock as normal. First of all, I should use vodka instead of star san, right? My crash won't be below 32* but I didn't want to worry about star san freezing. And of course, using an air lock could result in suck back anyway. However, if I use a three piece air lock, as long as the liquid in the air lock is below the opening up in the bell rocker, isn't it impossible for the air lock liquid to suck back? Like, physically impossible?

Option 3: Cover with sanitized foil and a rubber band. This is my least attractive option. Especially since I am trying to completely eliminate oxygen from the time I dry hop until it comes out the keg faucet (doing my first closed transfer on this beer too).

Thoughts?

 

[JONNYROTTEN]

FWIW Ive never had cardboard taste in my beer and simply crash in the primary with the airlock full of water.I drink my beer pretty quick though,from tap to kill is usually around 2 weeks or so.Ive heard lately oxidation taste/issues takes longer to become apparent so its a non issue foe me.Although I had a keg last over a month with no off taste..My biggest taste issue is yeast bite even after crashing,bitter nastiness

 

[BlueHouseBrewhaus]

A 3 piece airlock will get suck back. I use an S-lock for cold crashing since it doesn't suck back as long as you don't over fill it. I always use vodka.

 

[TravelingLight]

A 3 piece airlock will get suck back. I use an S-lock for cold crashing since it doesn't suck back as long as you don't over fill it. I always use vodka.

Interesting. So even if the liquid in the airlock is below the opening that the bell sits on, it can still suck back? How is that even possible? Not that I don't believe you, I just can't wrap my pea brain around the logic of it.

 

[brandonnys]

RDWHAHB.

Put an S lock with vodka on it. No need to worry a whole bunch about it.

 

[ballsy]

I've always just emptied the airlock and covered with piece of star-san dipped foil. Never had any problems with it after 4 years of doing it.

 

[TravelingLight]

RDWHAHB.

Put an S lock with vodka on it. No need to worry a whole bunch about it.

I've always just emptied the airlock and covered with piece of star-san dipped foil. Never had any problems with it after 4 years of doing it.

Thanks guys. I think I'll just do the s-lock with vodka and make sure it's not overfilled. Ain't too worried 'bout it!

 

[freisste]

Another option is to rack to a keg and cold crash under pressure. Best way o eliminate the issues you describe. Pour off a couple pints of crap and you're good to go.