Ferm Fridge Builds

[Tricerahops220]

Does anyone on here have a good link to a fermentation chamber build of someone taking apart and utilizing the guts from a NEWER mini fridge? I have attempted this and failed (can't hold temp) and I am looking to see what others may have done to make theirs work.



For those who may be unaware, the newer style mini fridges have the evaporators located within the skin of the unit (not on the back like the old style).



Any help would be greatly appreciated.



I can post pictures of what I have built if there are any refrigeration experts on here.

 

[Ozarks Mountain Brewery]

yes that is the problem I have the old style and probably what your looking for, what I had to do is wedge a large electric fan inside the freezer compartment with a jell pack then take off the doors, I had to add a house fan zip tied to the coils to cool and thats really important then I took a 2 foot by 4 foot cardboard box and lined the inside and outside with 1" blue foam board R6 each layer then foil taped foil insulation to the inside, I have a inkbird controller running it and can get down to 50 if I want to, got some pictures coming up but there not pretty

 

[ericbw]

I gave up on my ferm chamber because it was hotter than it could cool. The fridge is about halfway in the box, but in a small space. So it heats up when the fridge is running. Now the ferm chamber is just a shelf, and we use an old fridge for fermenting. (The old fridge is having trouble getting below 60 degrees, though.)

 

[Tricerahops220]

Though your ferm chamber is nice, @Ozarks_Mountain_Brew, it's not really what I was looking for when I made this thread. I was looking to see if anyone has mutilated a new style mini fridge to make a box out of either insulation or wood and make what is essentially a larger ferm fridge. I was trying to avoid adding onto the existing mini fridge like what you have done for space constraint reasons.

@ericbw, that is the same situation I appear to be running into with mine, sort of. I removed the skin and the heat from the evaporator coils seems to be exceeding the cooling capacity of the condenser. I will attach pics for reference.

 

[Tricerahops220]

View attachment ImageUploadedByHome Brew1498317922.644372.jpg
The coils run behind the insulation on the right, over the top and down the left side before going out the back.

View attachment ImageUploadedByHome Brew1498317942.416990.jpg
This is what you see from behind

View attachment ImageUploadedByHome Brew1498317958.892754.jpg
Here is the small notch I cut from where the coil runs out the back.

 

[Ozarks Mountain Brewery]

Though your ferm chamber is nice, @Ozarks_Mountain_Brew, it's not really what I was looking for when I made this thread. I was looking to see if anyone has mutilated a new style mini fridge to make a box out of either insulation or wood and make what is essentially a larger ferm fridge. I was trying to avoid adding onto the existing mini fridge like what you have done for space constraint reasons.

@ericbw, that is the same situation I appear to be running into with mine, sort of. I removed the skin and the heat from the evaporator coils seems to be exceeding the cooling capacity of the condenser. I will attach pics for reference.

unless you can cool those coils it will not drop below 70 , at least mine didn't and will just keep running then overheat, those mini fridges aren't meant to run more than a minute so if you cant cut the back off im not sure its even worth trying

 

[Ozarks Mountain Brewery]

I didn't look at your set up sorry, starting to look good, so does it work now?

 

[Tricerahops220]

No it doesn't work at all. I ran a test batch of water through it and it did fine. But I tried to throw a batch of beer in it and it was an epic failure. Threw the beer in and couldn't get the temp below 90. The space around it was cool when I would pull the door off, i felt a rush of cold air but the actual conical I put in it was still warm. Ended up loosing the batch.

I may try and throw another water test in there and wrap it with ice packs to get it down to roughly what would be pitching temperature then see if I can shut the door and see if it will hold. But either way it would be damn near impossible to emulate the heat produced by yeast.

 

[Tricerahops220]

Abandoning ship. This was a failure without even breaking the refrigerant lines. I'm looking for a stand up freezer now on CL.

My suggestion to anyone is try to just take the door off of your mini fridge and keep it in one piece. If you choose otherwise and succeed, all the credit to you.

 

[audioa84]

I can commiserate. I bought a brand new mini-fridge, tore it apart carefully and ended up having one of my kids knock into it and kink/break a line. I was so frusterated. I am now on the lookout for an older-style mini with the radiator style system on the back. I think I will have more success with that one. I'll let you know how it goes.

 

[V-Fib]

I got a free older fridge on CL and bought an inkbird thermostat. I did have to sawzall out some insulation on the door, built a wood shelf out of 2x3 and 5/8" plywood and it fits to 6.5 gal carboys. Its a side by side so the freezer is useless but it was simple and free.

 

[crane]

I am now on the lookout for an older-style mini with the radiator style system on the back. I think I will have more success with that one. I'll let you know how it goes.

I had great success with an older style mini fridge. Check my build link in my signature. I built it so it would not be too hard to pop out the rear piece of insulation and remove/replace the guts if it happens to stop cooling on me. Fortunately, (knock on wood) it's still working great after 6 years.

I think part of the problem with the OPs failures have to do with the wood skin on the outside. Wood is a much better insulator than metal, so it's trapping the heat inside causing the insulation to heat up. I would try removing or cutting the plywood to expose those lines to air and see if that makes a difference.

 

[robertlhawley]

Possibly not in the spirit of the OP request, but I've got a hybrid of new and older-style mini-fridge, and it's a different approach than anything I've seen..

Using the body of the newer fridge as essentially the insulated box and the guts of the older fridge as the cooling unit, the whole thing controlled by a BrewPi:

http://hanoverhomestead.blogspot.com/2015/11/the-frankenfridge-mini-fridge.html

It's been working great for me for almost 2 years of pretty much continuous fermentation, both heating and cooling. Large enough to hold a Sanke keg for fermenting 10 gallon batches...

Hope it's helpful!