Fermentation chamber and mini fridge sizing ?'s

I have a Haire 5 cft mini fridge and i'd like to build a fermentation chamber that also contains enough space for serving beers.

My problem is that i'm not sure if 1 mini fridge would be able to cool the entire area.

All said and done my interior dimensions are 6' wide x 2' deep x 3' tall.

I'd like to keep a 2' 11" x 2' x 3' chamber at 40deg and use fans to keep the other 2' 11" x 2' x 3' chamber at 60-65 deg.

Any way to determine if this mini fridge could do that?

NinjaJoe said:

Any way to determine if this mini fridge could do that?

Click to expand...

I did a similar build, except the one chamber was 2 deep by 3 wide by 2.5 tall. The chamber could get to 45F but was close to burning itself out even in a 70F garage. (Compressor was way too hot to touch.) It can maintain 65F in a 70-90F garage with some straining (i.e. running about 50% of the time.) I think it was a similar sized Haier.

Your chamber is twice as big, so you'll see about 30% more heat ingress. If you want to maintain 65-70F in a not-too-hot area it would probably work, but you might be pushing it if you're in a hot area or you really want to keep it at 40F.

In general, refrigerators don't have much of a design margin. If you want to keep stuff at 40F (which is close to its design temp) you're not going to be able to handle much additional heat load. If you want to keep it at 65F you have a lot more leeway. Depends on external temps as well; even as-is, a refrigerator will have a very hard time keeping its internal temp at 40F if it's kept in a hot garate.

After doing a little more measuring i'm making a few changes. This will be indoors so the temps should stay pretty stable 68-74 year round

New chamber dimensions.

Ferment:
24" x 24" x 32"

Dispense:
24" x 36" x 32"

I worked out the math for determining this in an earlier thread: https://www.homebrewtalk.com/f51/what-kind-r-value-ferm-chamber-190459/

Good luck!

RegionalChaos said:

I worked out the math for determining this in an earlier thread: https://www.homebrewtalk.com/f51/what-kind-r-value-ferm-chamber-190459/

Good luck!

Click to expand...

Awesome, thanks! I've made some more dimension changes as it was just to big overall to ferment 4 batches and dispense 6 kegs. So I dropped it down to fermenting 2 batches and dispensing 6 kegs.

New dimensions (interior):

Ferment:
12"x24"x36"

Dispense:
28"x24"x36"

Went and grabbed 60ft of 2x4's and 40ft of 2x3's and will get to measuring and cutting tomorrow.

And here are results from the equation that RC posted.

Q=(75-40) * 19.8/10
Q=69.3

So sticking with 1.5" R10 I should be good to go!