Venting CO2

Should I be worried about CO2 pressure build up in my fermentation chamber. This is what I have so far. 3/4" plywood cabinet sealed with silicone caulk, a layer of 1" XPS insulation with foil tape in corners. I have a door that I made with 1/2 overlay hinges like a standard cabinet but I think I’m going to redesign it to something that will seal better. I’m wondering if I create an air tight cabinet if I need to worry about pressure buildup. If so how should I vent it?

I don’t have any experience with building a ferm chamber, but if venting were necessary, a studer vent (available at Lowes or Depot) would work. It’s a one way air valve, and they’re pretty cheap. will require about an 1-3/4" hole somewhere on the cabinet as it mounts on 1-1/2" pvc pipe. You would put it on the inside since it is designed to let air into the pipe.

Cheers,

Ron

Definitely a little vent.I don’t think you want positive pressure inside it may impede fermentation. I don’t think you need a studer vent your not worried about sewer gas. I would just drill two small holes one high one low.

Before I had my 2 heated/cooled conicals I fermented in a chest freezer. It didn’t have a vent and I never needed one. I fermented 10 gal batches in 2 carboys without issues.

I’ll be pretty surprised if you can seal that door well enough to prevent it from burping out excess pressure. That is a lot of surface area, and it will create a LOT of force if it builds up enough pressure to affect fermentation.

Not sure it has to be air tight. What are your plans for cooling and heating?

First I need to see how well it is insulated and see how it holds temp. I have a portable a/c unit that I could use. I might see how hot the exhaust air is for heat and obviously the cold air from it to cool it.

I have a portable also that I was thinking of trying to make a chamber with. Make sure you update this post. I’m looking for ideas.

Why not drill in a bung for an airlock?

[quote=“rebuiltcellars”]I’ll be pretty surprised if you can seal that door well enough to prevent it from burping out excess pressure. That is a lot of surface area, and it will create a LOT of force if it builds up enough pressure to affect fermentation.[/quote]I agree with this statement 100%. If you are still not sure, use an airlock as suggested by harpdog.

It’s exceedingly unlikely there’s even an issue with pressure build up.

And even if the devil starts that snowball fight, all you gotta do is remove a tiny bit of whatever magic substance was used to create an airtight seal using only pressure from cabinet hinges.

My question though, do you have enough room in there for a fermenter AND a blow-off bucket?

I use a previously emptied bourbon bottle filled with star San. Never had a problem. For bigger beers I use a 9 gal bucket. It looks like plenty of room for that. I’ll bet you can make it air tight but not with cab hinges. The air lock sounds good. Maybe make an open fermentor

Nice cabinet ! I’m fairly new to this great hobbie - my question would be why would it have to be so air tight

[quote=“JMcK”]It’s exceedingly unlikely there’s even an issue with pressure build up.

And even if the devil starts that snowball fight, all you gotta do is remove a tiny bit of whatever magic substance was used to create an airtight seal using only pressure from cabinet hinges.

My question though, do you have enough room in there for a fermenter AND a blow-off bucket?[/quote]

Thank you. It doesn’t have to be completely air tight but like a cooler full of ice you wouldn’t want to leave the lid open. It needs to keep the temperature inside of it. I plan on changing from cabinet hinges to something that will have a better seal.

That’s a lot bigger than it appeared without the carboy in it. Much bigger than I thought it was …

Might be able to stack two buckets with a shelf.

Interior dimensions are 18"x18"x32"