Cold crash question

Northern Brewer General
1

So I am cold crashing for the first time , and the airlock is moving in reverse sucking air back into the carboy. I understand the physics of it but don’t like it. It is obviously sucking air with O2 back into my carboy. I suppose since CO2 is heavier than air, there will still be a blanket of CO2 over the beer to stop oxidation but it feels wrong. Any opinion/experience out there. Should I have done something else?

Thanks, t

2

It’ll be fine. It’s just negative pressure doing its job. The C02 blanket will keep your beer safe.

Once the temps equalize, the air will get pushed back out by the c02.

3

If you’re cold crashing, fermentation is over and you don’t need an airlock. Just seal the fermenter with foil, plastic wrap, etc.

4

Just loosen the air lock every couple hours as it cools down. Once it is cool, it will stop sucking in