I'm using my keezer as my ferm chamber for the first few days of my Hefe's fermentation. This morning I opened the door and stuck my head down inside to get a good look (not using a blow-off tube due to lack of room and cool fermenation anyway - but want to be sure the airlock isn't getting cruddy).
Upon sticking myhead below a certain level, I breathed in a nice breath of sulfuric/burning type air up my nose.
I've seen this in a couple of ferm chamber build posts posed as a question but I couldn't find a good answer - any problem with CO2 buildup in a ferm chamber? Probably less so for mini-fridge conversions, as the door would open and let out the CO2. But for using a keezer type setup, where the door opens up and the heavy CO2 rests inside?
The only type of gas I am familiar with supports the Dutch Oven. So thought I'd ask the question.