New fermentation chamber build

[TwoHeadsBrewing]

I have a friend who did this. His cooling source was a chest freezer. He put a temp controller on the freezer to keep it at 35F for lagering and serving kegs. He had two 120mm computer fans that were hooked up to a thermostat which he set for 50-60F. Those fans were mounted on the wooden collar of his keezer and blew the air through a pair of 4" insulated ducting into his plywood insulated fermentation chamber. It was very similar to the build listed above, but using a chest freezer instead of an A/C unit.

 

[balvey]

Ok, well I've started my build. So far I've got the base and the top put together. I'm going to work on the side supports and doors tonight or tomorrow.

I'm making it a mobile unit by building the base with a floor that is long enough for the chamber, the fridge, & CO2 tank. All of that is on casters. The whole thing is about 6.5' in length. The height is going to be about 3.5' from ground to counter/bar top and just about 6'' deeper than the Magic Chef mini fridge at around 25''.

I'm lining it with 2'' pink extruded poly-styrene and going to put a divider inside to make the serving chamber 24'' wide and the ferment chamber 28'' wide. I'm thinking the divider is going to have two holes at the top in each corner. One with a thermostat controlled pc fan blowing into the serving chamber. The other will have a baffle going down to bottom of each side. That way cold air at the bottom can't continuously flow to the ferment chamber.

I'm thinking I'm going to do a coffin tower to mount the taps. I'll either have 3 or 4, I had planned on 4 but I didn't take into account the 2'' thickness of the insulation, so I may not be able to fit 4 kegs but it'll be close.

The ferment chamber should fit two buckets or 3 to 4 kegs.

I'm just having a little trouble figuring out how to control the temp of the lines going to the taps once they are outside of the serving chamber up into the tower. I guess I could get some pipe insulation and try that first, or try to rig up some pvc to run them through that will go down into the chamber and then fill it with GreatStuff insulation. I just don't want to make that a potential cold air leak problem.

 

[mikeysab]

Bumping this one for a quick question. I was going to go with the SOF design until I saw this idea. I have a 4.3 cf mini that my wife would kill me for adding to the brewery. I've been scouring Craigslist for a mini to use for this build. Anybody think one of the smaller mini fridges would work for this, like a 1.7 or 2.5, or would I need a bigger fridge? I really like this idea, but finding a cheapo mini fridge has been a bit of a task. whaddaya guys think?

 

[marshallwms]

I think the answer depends on how cold you want the chamber to be, and how large. If you want to lager a 5 gal. carboy, I don't think the 1.7 would work at all, and the 2.5 might be iffy at best. You are probably better off being patient. When the college school year ends, there are usually a bunch of 4.3 cf sized fridges available on CL.

 

[uabericm]

I just completed building my chamber and I'm having issues getting the chamber to drop below 48*. The fridge stays on the entire time and it just won't drop. I cannot find any leaks, but when I built the chamber I have the fridge enclosed except for the back and 1" up the side. Am I "choking" fridge, not allowing it to release it's heat, so it can't cool?

 

[stratslinger]

To the OP:

Just yesterday I acquired a Magic Chef mini-fridge that looks to be identical to the one you used in this build - and I plan to more-or-less duplicate your design. In your build, did you ever bend down the cooling coils, or did you leave them as-is?

I'm going to be doing up some sketches and such, trying to figure out just what I need for materials, in the hopes of doing such a build in late March or early April...

 

[BrewersKaramazov]

I just completed building my chamber and I'm having issues getting the chamber to drop below 48*. The fridge stays on the entire time and it just won't drop. I cannot find any leaks, but when I built the chamber I have the fridge enclosed except for the back and 1" up the side. Am I "choking" fridge, not allowing it to release it's heat, so it can't cool?

I just picked up a kenmore mini for my build. It radiates the heat out the sides near the back. If you have the sides insulated, it may not be able to get rid of the heat. If you can pull it out and run it, you will quickly be able to feel where the heat is being released.

There is also a bunch of great math on here that you can do to figure out the difference from your ambient temp. You may not be able to get much lower.

 

[nootay]

thanks for posting this! i plan on doing this in the next few weeks. i see you mentioned you need to have airspace between the insulation and the plywood. how did you create teh airspace? did you have some thin wood between the insulation and outside plywood?

 

[nootay]

Just about got mine done. Need to finish up the door and caulk a few places. Is it necessary to put computer fans in? If so is there a write up on the wiring of them?

 

[-MG-]

Is this method still viable if you were planning to use this to ferment 2 12 gal batches in sankes at around 48 degrees? What about if you wanted to lager, would it just burn out the motor?

 

[joelrapp]

Well, since the weather has been cold these past few months I've been fermenting in my walk-in closet. Yeah...SWMBO has not been particularly thrilled with the glorious smell of fermentation! So, as the warm weather approaches I've been planning out a fermentation chamber build for the garage. I've got a nice workbench that seemed like the perfect place.

I fitted the fridge in the left hand side, firmly situated against the 2x4 frame of the shelf behind it.

Next step: add some framing on the floor and the back wall.

Then some insulation for the back wall and a plywood floor to adhere the insulation:

Well now you have me thinking

 

[DrewschBag]

Not sure if it has already been suggested, but anyone considering this project in the future may want to think about a lid instead of the door on the side. This would probably be a bit more efficient.

 

[mikeysab]

I think the problem with that is lifting x gallons of liquid up over the sides and down into the chamber. The door on the side is much easier. A little weather stripping around the door and you're good to go.

 

[forcabrew]

so i will be building a ferm chamber very similar to this in the next couple of weeks and i was wondering if a regular roll of fiberglass wall insulation would work? i have an entire roll in my basement left over from some home improvement projects.

 

[stratslinger]

I think compressing standard fiberglass roll insulation would significantly reduce its insulating properties - its largely effective because of the amount of air space that is trapped in between the fibers. The rigid foam most of us use in builds like this is designed to work in much smaller spaces.

 

[Eshorebrewer]

This is exactly what I'm trying to do under the workbench out in my garage! Awesome build.

 

[Riddei]

LOL, thanks for looking! I had a similar problem with all of my beer in our walkin closet off the master bedroom. After an especially stinky batch of hefeweizen, followed with 25 gallons total in there...well you get the picture. SWMBO finally said, "hey, did you get all the supplies for your fermentation chamber yet????".

My wife is kicking me out of the closet too. After seeing this thread, I have restored hope. Thanks for posting!

 

[Anon]

Bumping an old thread but I really like this idea! Going to check out c-list for a fridge and start this up!

 

[Schlomo]

Got my fridge today. Planning on this same design, but not under a workbench. I'm aiming for a rolling fermenting chamber!

 

[Schlomo]

I built this same design over the last week and got it all together and sealed last night. I got it down quickly to 50f and it easily held there so i'm pumped that I can now lager! I would recommend this type of build to anyone looking for a cheaper alternative to a chest freezer, mine takes up less room and can hold 3 carboys/buckets or multiple cornies for conditioning.

 

[mojo2008]

THB (or anybody else who has built this device),

Have you had any luck getting to temperatures as low as freezing?

Thanks!

 

[TBaGZ]

Looks like my chamber is not insulated so well or is just too big. My garage gets to be well over 90 and it is struggling to get to 65 Ambient in the box. It gets to temp, but won't hold longer than a few minutes. The fridge unit is cycling almost constantly. I have it doubled up with two layers of 3/4 foam, and calked the seems and corners. I used foam weather stripping on the door for a seal. I do have a fan in front of the cooling plate now, too.

 

[TBaGZ]

oops.

 

[TBaGZ]

It won't hold 2* ambient for ten minutes.

 

[govner1]

Did you also out insulation under the floor? It's hard to the from the photo. On my two chambers I've just incorporated the original fridge as a orr of the construction by just removing the door. Mine have cooling circulating in the side walls , too. Not just the cooling plate/freezer.
Also mine are in a garage brewery that can get hot during Summer (GA). No problems w/ temp control.


Sent from my iPhone using Home Brew

 

[TBaGZ]

I did insulate under the floor as well. I didn't want the whole body of the fridge hanging off the side because the wall that it is on is tight on real estate with all the other stuff over there. Wouldn't have been a problem if my HOA would let me have a shed, but..... Yeah no.

 

[TBaGZ]

Yeah, it just doesn't hold ambient temp in the chamber. It does "OK" when the sensor is on the ferm vessel because of the mass, but otherwise not so good. I have two layers of 3/4 insulation all the way around with the seems caulked. Do you think it is because I have the insulation up against the chamber walls with no air gap? I would like to get this thing to work.

 

[stratslinger]

Hang on a sec - why would you want it to hold a given ambient temp? This is your ferment chamber, so the key thing you want to maintain is your fermenter temp, right? So if it's maintaining a given fermenter temp when the sensor is strapped to the fermenter, where is the problem? Help us understand why you'd want to maintain a given ambient temp - I personally can't think of a real reason I'd give a hoot about ambient temp in my chamber, if the fermenter is stable.

 

[broadbill]

THB (or anybody else who has built this device),

Have you had any luck getting to temperatures as low as freezing?

Thanks!

I don't think this would be even remotely possible. My experience with mini-fridges is they barely keep things stored in their freezer section frozen, and that is in their unmodified state. Here you are greatly increasing the volume of the cooled space...

I would expect best case scenario with this setup would be to maintain ale-temps (60-65F) at fully-loaded capacity. I'd be surprised if it could hold lager fermentation steps (50-55F), and no-fing-way to lager temps and below. I usually shake my head at these types of builds...all this work for limited functionality, considering you can do a used chest freezer setup at half the price which will easily take you down to lager temps.

Disclaimer: I haven't built such a device.

 

[TBaGZ]

If it would hold a better ambient temp it wouldn't have to run so much to hold the fermentation temps.