Fermentation CHamber reached 15 degrees above ambient. Too big?

[TGnB]

I've built a fermentation chamber that is 5'x'3'3' with a minifridge for cooling and a 250 watt heat lamp for heating. Temperature is controlled by the Inkbird ITC-308, which seems to work great.

the frame is built with 2x4s, and R9.8 insulation covered up with half-inch OSB.

PICTURES HERE http://imgur.com/a/zgBeE

My problem is the chamber just won't get cold enough, and yesterday morning was 15 degrees above ambient. I set it to 64, ambient was about 62, and I checked it in the morning and Inkbird was telling me it was 78 degrees in there.

I opened the door and ran the box fan in the pictures blowing into the box and things cooled down well.

Where is the heat coming from? There is currently about 24 gallons of beer in there that was brewed on October 3rd and October 4th and its fermenting away. I maybe have overpitched the yeast.

I know that fermentation produces heat, but 15 degrees over ambient with a minifridge running full blast and three fans to circulate air? One of the is a big square window fan.

Any ideas on why its so hot in there and how to cool it down? I may purchase a used AC unit tomorrow and add in there but I would appreciate any ideas.

 

[Pappers_]

My only idea is that the mini-fridge innards aren't working very efficiently. 24 gallons of fermenting beer in a small, well-insulated space will produce quite a bit of heat, but I would share your concern - 78F is way too high.

I guess the fan motors might be producing heat too?

 

[corkybstewart]

I tried the same basic idea, the fridge just doesn't cool a large space. Go down to Lowes or Home Depot, they are closing out window AC's for the winter. I have a 8000 BTU model and I can get my fermentation temps down to lagering temp even in the summer.

 

[TGnB]

There is ice on the inside coils of the fridge, and my inkbird temperature probe taped to the side of the bucket said 78 degrees.

I tried the same basic idea, the fridge just doesn't cool a large space. Go down to Lowes or Home Depot, they are closing out window AC's for the winter. I have a 8000 BTU model and I can get my fermentation temps down to lagering temp even in the summer.

A window AC unit was going to be my next move, and now I wish I went with it in the first place as it seems to make more sense.

With your 8000 BTU model, how big is your chamber? mine is 45 cubic feet which may have been rather ambitious.

I am interested in brewing lager, but I've haven't yet been able to achieve low enough temperatures. Do you think an AC unit similar to yours could cool my 45 cubic foot box down to lager temps? Current ambient temp has been low 60s (down from low 70s). Not sure what to expect this winter but I remember the gas heater making it pretty warm down there.

 

[bcrawfo2]

I recently went thru the exact same thing. My chamber is about 30 cubic feet and I was using a mini fridge. It would cool ok with no real load, but I think one of my last batches pushed it over the edge. I think I ruined a 10g batch of IPA due to heat.
I've switched to a 5000 BTU window unit, it's what I had already.
I had problems with it freezing up, so I had to get creative with my BCS programming. My chamber is currently a little leaky (due to quick addition of the window unit). I can get down to 40 degrees in my basement...and I don't even have the floor insulated. Good luck. Hope your beer survives.

 

[TGnB]

Thank you for the reply.

Do you think the 78 degrees ruined the beer? it wasn't for more than 6 hours or so, but it was during the most vigorous phase of fermentation

 

[corkybstewart]

There is ice on the inside coils of the fridge, and my inkbird temperature probe taped to the side of the bucket said 78 degrees.




A window AC unit was going to be my next move, and now I wish I went with it in the first place as it seems to make more sense.

With your 8000 BTU model, how big is your chamber? mine is 45 cubic feet which may have been rather ambitious.

I am interested in brewing lager, but I've haven't yet been able to achieve low enough temperatures. Do you think an AC unit similar to yours could cool my 45 cubic foot box down to lager temps? Current ambient temp has been low 60s (down from low 70s). Not sure what to expect this winter but I remember the gas heater making it pretty warm down there.

http://i362.photobucket.com/albums/oo65/rocdoc1/my beer stuff/WeeHeavyOctober2009014.jpg

I think the interior dimensions are around 55 inches tall, 24 deep, 26 wide. That's a 12.2 gallon fermenter. I have 2 inches of styrofoam insulation, 1/2 inches of bubble wrap.

 

[angrybits]

Do you think the 78 degrees ruined the beer?

No, it just changed it. It'll still be beer at the very least, and chances are it'll still be good beer.

 

[corkybstewart]

Thank you for the reply.

Do you think the 78 degrees ruined the beer? it wasn't for more than 6 hours or so, but it was during the most vigorous phase of fermentation

I had an imperial stout that got out of control, it was at 85F when I checked it. I got it cooled down to 65, then fermented it out. When it got to FG it tasted like kerosene, but after 2 more weeks in primary it was delicious. Let it sit long enough for the off tastes to go away.

 

[mbbransc]

http://i362.photobucket.com/albums/oo65/rocdoc1/my beer stuff/WeeHeavyOctober2009014.jpg

I think the interior dimensions are around 55 inches tall, 24 deep, 26 wide. That's a 12.2 gallon fermenter. I have 2 inches of styrofoam insulation, 1/2 inches of bubble wrap.

I've seen your pic a bunch over the years on here at BA. I've just now got a conical and dealing with the issue of temp control. Did you override the AC's thermostat? I'm having problems figuring out how to do this. When Google'g it, most link just tell you not to.

 

[corkybstewart]

I didn't override it, I think I just removed the actual probe and put it so that it hangs outside the box, ensuring that the thermostat never reads below the ambient temp of my garage. Not the most noteworthy and elegant solution but it works and was free.