Fermentation Chamber w/ Refrigeration

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thomcat333

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So I bought a small used minifridge for $25 and have successfully taken all of the mechanical and electrical bits out without releasing any refrigerant. My plan is to build something similar to the "Son of Fermentation" chamber, only I'm planning on cooling it with the internals from the small fridge. I've got a temp controller and thermocouple on the way...

Yes, I'm basically building a franken-mini-fridge. Has anybody else seen this done???

I am just freakin tired of tending to the towel and fan...

Wish me luck!
 
I've got a small freezer I could cannibalize...please post your pics and methods....I'd definitely be interested! Incidentally, how'd you manage to get it apart nd not spring a leak? I don't know if I have that kind of finesse.....
 
I'll post pics as things progress. As for the extraction, the first round involved a screw driver, the second some pliars, the third a set of good tin snips, and then I finally got her out in one piece.
 
I have a small dorm fridge I saved from a landfill purgatory that I was planning to do the same with soon. The difference is I was planning on using it as a pseudo-window unit air conditioner. I was planning on building a a fermentation chamber to fit a spot in my brew area, then build a shelf on the back with a hole slightly smaller than the from t of the fridge. I would then remove the door and hinge materials and affix the frige to the box with a a rope that allows tension by tightening a threaded rod and sandwiching insulation to ensure a good seal. I was planning on starting construction this week, and was gonna post pics, however, depending on how you do, I may modify the approach.
 
I think you may have spent a lot more time and energy than was necessary. You could have built a large rigid foam box with a hole in the side where you'd put the mini fride with the door taken off. A little caulk where they meet up and you're good to go. I'd run a small fan in there just to keep the air circulating in any case.
 
Ryan_PA said:
Perhaps, but if we all adopt the minimalist approach on everything, we would be walking around wearing burlap sacks and eating off the floor. ;)
I don't think I'd mind, as long as I have a steady supply of homebrew. :D
 
Ryan_PA said:
Perhaps, but if we all adopt the minimalist approach on everything, we would be walking around wearing burlap sacks and eating off the floor. ;)
The world may come to that but I bet half the people on this site would be looking for something to brew instead of learning to sew...;) :D
 
homebrewer_99 said:
The world may come to that but I bet half the people on this site would be looking for something to brew instead of learning to sew...;) :D

Mr. Fancy Pants is gonna have a sewn sack. I would lean towards the toga-like knot.

My real point was that my brew area, albeit the workshop portion of my basement, still needs to look decent in the eyes of the wife, plus I plan on having my chanber last a few years. That is why I was looking for something more sturdy and aesthetically appealing than the foam board box, but that is all one really needs.
 
I, too, would like to see a picture of the in-tact fridge hardware sans cabinet and foam.

Sounds neat, but I'm probably only going to remove the door and cut the top off of my dorm-cube fridge when i convert it into a ferm cabinet. maybe the the sides, if needed.

good luck.
 
Okay... finally an update here. Below are the internals from the minifridge that I extracted. FYI, in many small fridges, the freezer IS the cooling coil. So, you're basically stuck with it unless you want to get a lot more complicated. I didn't realize this until I took the thing apart.

10254-Mechanicals.JPG



With the internals taken out of the minifridge, I started to build a wooden frame around which to build my fermentation chamber. Below shows the frame alone and then with some of the outside pannels.

10254-Frame.JPG


10254-Frame2.JPG


Ok, so that's where I am. I've purchased some 2" foam board insulation that will go inside, lined by some water-resistant panneling. I'll post more pics as this thing progresses.

I've got a PID and thermocouple in the mail, so that's on deck. I'm glad that there are others that enjoy going overboard on things like this. I've never been a minimalist I guess. Wish me luck!
 
Have you considered extending it about 2 feet or so? You may want to have more than one carboy in there at a time. If there's anything you want to secondary, you'll want that to be temp controlled as well. That secondary can sit in there for up to a month, and then you're screwed for when you want to put a primary in (and that's where temp control is crucial).
 
I just did this recently. It's alot of work, but works pretty well. I built two different compartments which run on separate fridge guts so I can control each compartment at different temperatures:

5958-Untitled-1.jpg


5958-Untitled-5.jpg


5958-Untitled-2.jpg


I lined the compartments with foam and then aluminum flashing.
 
That looks awesome... I have a few dorm fridges around the house and I have been thinking about making one of these to hold a few carboy's, but I also want to make it tall enough to hold corny's... I've seen a few custom bars that were made this exact same way...
 
Yeah, good call on the extension. It would have been nice, but my space is limited at the moment, and I don't brew that often right now (~1 every 5 or 6 weeks or so). If I lived in a house (w/ a basement or more space) I might have considered it I guess... But, to alleviate the issue, I'm planning on converting a Sanyo 4912 (or other if a better option comes up) into a keggerator after Christmas. So, I'll be able to keg and effectively do my cold storage there prior to serving.
 
I was a bit leerie on using the guts from a single mini fridge to cool more space than enough for one carboy. The mini fridges used are usually only about 1.5 cu ft capacity, and to fit a carboy I used compartment sizes of about 14x14x25 inches which is about 2.8 cu ft. I figured enlarging that the space to fit another carboy or cornies would cause you difficulties getting the fridge temps down to lagering temps.
 
iamjonsharp said:
I was a bit leerie on using the guts from a single mini fridge to cool more space than enough for one carboy. The mini fridges used are usually only about 1.5 cu ft capacity, and to fit a carboy I used compartment sizes of about 14x14x25 inches which is about 2.8 cu ft. I figured enlarging that the space to fit another carboy or cornies would cause you difficulties getting the fridge temps down to lagering temps.

Hmmm....good point. I've got a 5 cuft freezer I may disassemble. Maybe it'll be a bit more effective. ThomCat- What kind of PID/Thermocouple did you get? I've seen some pretty cool ones out there, with illuminated digital readout, etc.
 
Mini fridges are fairly easy to take apart because the evaporator and condenser coils are neatly packed together, as you can see in ThomCat's photo, the black coils (condenser) and the freezer compartment unit (evaporator- I think thats the what they're called). Taking apart larger fridges and freezer will start to get more complicated as the coils can be wrapped all over the fridge and the fridges/freezers also may have fans. I would be careful when looking into taking apart a bigger fridge or freezer to see if it would actually be feasible to do.

Minifridges seem to work great, however. The coils leading to the condenser and evaporator are flexible and you can flip the freezer compartment upside down to minimize the space needed to fit in a carboy and airlock. If your airlock is going to be really close to the freezer compartment, make sure you fill it up with vodka so it doesn't freeze.

ThomCat: Water resistant paneling is a good idea, also tape off or caulk the cracks in the foam. I've got an ale in one of the fridges, when the fridge cools down frost forms on the freezer compartment. When the fridge hits the correct temp in the 60's and turns off, the frost melts and water drips down to the bottom of the fridge. It's not very much water, but you will want to make sure it won't leak out of the fridge or down into the foam/wood. Putting a small towel under the carboy will more than likely solve this problem. I am assuming condensation won't be a problem when the fridge is at lagering temps.
 
Wow, thomcat, that frdge hardware looks really neat standing there sans cabinet. Looks like some fine craftsmanship of your frame, too.

thomcat333 said:
I've got a PID and thermocouple in the mail, so that's on deck. I'm glad that there are others that enjoy going overboard on things like this. I've never been a minimalist I guess. Wish me luck!

Just make sure you use that controller in On/Off mode instead of PID mode, lest you want to burn out your compressor. On/off operation can still give you a pretty tight tolerance.

iamjonsharp, that's also a nice looking setup. This may be a silly question, but does the compressor need to stay upright or could it be mounted on it's side or upside down?
 
I'm not 100% sure, but I've heard that you shouldn't keep a fridge on its side or upside down...so the compressor should probably stay upright. Anyone know for sure?
 
iamjonsharp said:
I'm not 100% sure, but I've heard that you shouldn't keep a fridge on its side or upside down...so the compressor should probably stay upright. Anyone know for sure?

I hear the same on this. I would keep everything in the position it was originally mounted in.
 
i actually just finished doing the same thing last week with my old dorm fridge. i built a 4'x2'x3' box with extruded polystyrene as the insulation and the gutted dorm fridge as the my source of cold air. i also bought a temp controller device to precisely control the temperature of my fermentation. it'll hold 3-6 gallon carboys and a couple cornies. oh yeah... getting the components out of the fridge wasn't very fun, but everything else is pretty easy!
 
iamjonsharp said:
Taking apart larger fridges and freezer will start to get more complicated as the coils can be wrapped all over the fridge and the fridges/freezers also may have fans. I would be careful when looking into taking apart a bigger fridge or freezer to see if it would actually be feasible to do
.

Yeah, my freezer is a small model, but it's pretty much jacketed in steel. I'll take a look at all the hardware and see if I can get the guts out without having to use a cutoff tool.:D
 
8/3/07 update:

So in the past day or so, I've made a bit more progress (thanks for the comments!) and I've received some goodies in the mail.

Ok so on we go... first I got the outer panels on. The pic below is in process...

10254-OuterPanels1.JPG


After they were on, I started cutting foam insulation to fit. I used 2" styrofoam board only because it was staring at me in Lowe's. If they sold the 2" extruded stuff, I would have used it, and that's what I'd recommend for those who know where to get it. The foam board is messy, but the effect should be comparable.

10254-Insulation1.JPG


And here's a rear shot. That foam board is thick!

10254-Insulation3.JPG


With the insulation in place, I lined the inside with a water-resistant board that Lowe's sells for laundry rooms, etc.

10254-InnerPanel1.JPG


Oh, and the duct tape you see around the outside is to keep the styrofoam board from breaking apart and hold it just a bit more snugly. Not the prettiest bit of work, but I'll probably cover it eventually. I'm still working on the door design.

It's been a good day of building. I'd keep tinkering tonight, but the neighbors downstairs wouldn't approve, and they're nice enough, so I'll leave them in peace.

continued...
 
Lastly, the previously mentioned goodies in the mail...

10254-Controller.JPG


Ok, so the temp controller I purchased has a green and red digital display (green = ambient; red = setpoint (or maybe it's the other way around)). Oh, and yes, I'll be using ON/OFF control mode to keep the compressor happy (good call!), but it does have PID capabilities if I ever needed to use it for something else requiring a variable input, so that's cool. Alongside is a Type K thermocouple. If any of you go this route, I'd look into RTDs which can give better accuracy, but the type Ks are cheap and pretty good. The controller has a built in relay, but they could be set up for an SSR also so I'm told. I'm not sure where I'll mount the display, but it's looking like it'll be in the back somewhere right now.

I took the old thermostat off of the compressor unit today and may get to do some wiring tomorrow. We'll see. I have to work this weekend, so I might get slowed down for a few days.

Cheers guys! :mug:

- Andy
 
Hey Andy,

When it is all said and done, you will have to give us a cost breakdown.

By the way, it is looking very nice! I have a dorm fridge that I can ferment a carboy in but that is about it, so this may be a project for me down the road!

John
 
Looking good, thanks for keeping us up to date. As for controller placement, my only advice is to not mount in inside the chamber. If it's anything like my omega controller (and it does look very similar :) ) it will produce heat, reducing the efficiency of the fridge, etc. You may probably weren't planning on that anyway, but just thought i'd mention it.

Also, I assume you are going to control the compressor relay, and not the compressor power, right? That's what i would recommend, anyway. Here's how i connected my controller:
medium.jpg


Edit: oops, hopefully this link works better, but the pic is a bit small. thanks john.
 
ScubaSteve said:
Yeah, my freezer is a small model, but it's pretty much jacketed in steel. I'll take a look at all the hardware and see if I can get the guts out without having to use a cutoff tool.:D

Just curious. Why would you want to destroy a perfectly good freezer?

You might want to consider using corny kegs as secondaries and for lagering instead.

Just a thought.:mug:
 
I just wanted to add, those of you that are concerned about using the "guts" from a tiny fridge to cool a much larger space, consider the following:

The small fridge is designed to keep things cold despite being opened and closed several times a day, and having warm food and drinks shoved in there periodically as well. If you only open the fermentation chamber maybe once or twice a day, and it is well-insulated, everything should be just fine. :ban:
 
abracadabra said:
Just curious. Why would you want to destroy a perfectly good freezer?

You might want to consider using corny kegs as secondaries and for lagering instead.

Just a thought.:mug:

It's a pretty small freezer. The bottom is about half compressor hump and the other half is probably big enough to keep 2 cornies. I have a larger chest freezer, but use this one to keep beer and soda. I could probably age kegs in there....I'm more concerned with having a separate place to primary so I don't have to raise my kegerator temp to ferment. This causes all my other beers to age too quickly.
 
Thomcat, excellent work. This is an idea I have thought about and it's great to see how it's done. If you could post some follow up information and a cost break-down on the DIY forum when you are done, I'm sure it would benefit alot of us.
 
By the looks of that white freezer section it looks like you would be able to S-L-O-W-L-Y press that out flat which would give you more room in the compartment.

With wooden strips you could form a slot to slide it in to...just a thought. :D
 
08/04/07 - Quick update:

I had a chance to get the last of the inner panels on as well as the compressor. It's mounted up and ready for electrical work. Good times.

The rear:
10254-Compressor1.JPG


And the freezer section on the inside:
10254-Compressor2.JPG


:mug:

- andy
 
thomcat333, that's some good looking work. I have been thinking about doing something similar only using peltier devices. Anyone here tried using them? I've got 2 12VDC thermoelectric coolers preassembled with sinks attached to both sides, 4 120mm dc fans and a 12VDC/5A power supply. I am going to put together a box with 2" hard foam large enough for 4 cornies and experiment a bit.
 
8/6/07 - So I worked the night shift last night, but I am off tomorrow, so I struggled through the day and drank a couple beers while I wired up the compressor.

I used a project box to enclose everything, and fed the thermocouple up under the back pannel to the opening for the evaporator coil. It worked out a bit neater than I expected. :)

Wiring In-Progress:
10254-Wiring1.JPG


Install complete:
10254-Wiring2.JPG


Controller Up-Close:
10254-Wiring3.JPG


On to the caulking and door construction...
 
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