FermKeezer

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diS

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After some thought, I decided to give it a shot and try to make keezer and fermentation chamber in one.

Actually it will be a two freezers connected via flexible or PP tube, where blowing and exhaust will be performed with PC fans controlled by STC100.
Freezer for fermentation is set vertically (like the fridge) so it takes up less space.

Nothing without Sketchup..

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So far, I removed compressor, painted old freezer lid in black and drilled intake pipe.

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We'll see how the project will evolve in the future..
Greatest challenge besides maintaining the fermentation temperature will be preventing moisture entering into the system.
 
I finally got some time to work on this project... fermentation chamber is almost finished.
few pics..

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Door fastener for better lid sealing.

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Bottom pipe is intake for cold air, and top pipe is for hot air, I"ll put another fan in reduction part to exhaust hot air to keezer.

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Interesting...

Are you controlling the Frem chamber with the keezer compressor?

Or are you running both compressors?
 
It will be 2 chambers and 1 compressor.

This is old freezer positioned vertical, I put styrofoam on bottom (now it is frontal) to reduce space and increase cooling efficiency. Other freezer (which will do the job for both) is pretty good insulated with 4" thick sides and compressor should be strong enough to maintain both freezers at appropriate temperatures.
Operation principle is similar to "Son of fermentation chiller" where one chamber provides a cool air and then fan blows it to the second chamber.
We"ll see real efficiency ant the end.

Ghetto but it will do the job.
 
Shouldn't the top be for cold intake since cold air falls? Why exhaust the hot air back into the keezer instead of exhausting it out into the open?

And it looks great so far.
 
Shouldn't the top be for cold intake since cold air falls?

Logical question, I've thought about it and I concluded that by putting "cold" pipe at top and exhaust downwards it would suck out cold air from the bottom, I think it is less energy efficient. Correct me if I'm wrong.

Why exhaust the hot air back into the keezer instead of exhausting it out into the open?

I would need some kind of irreversible (one-way) barrier in order to exhaust hot air and prevent moisture from entering the sistem.
 
hmmm, I like the idea of this and I think you are on the right track to make this work. I look forward to seeing this project along the way.
I do have one question, how did you mount that shelf inside?
 
Old freezer had two sections divided by barrier. Under shallower section there was compressor and this is where I put shelf, carriers were already there so I only had to cut and mount 2 pieces of glass (glued with silicone).
I put styrofoam under it and insulation tape on front (as you can see on last pic) to ensure insulation between fermentation and shelf part.

Shelf will probably be used for storing laboratory equipment because it is easy to disinfect.
 
So have you fired it up yet with it on its side yet? Just curious if the compressor and everything is running fine? Thought of this idea couple months back but didn't know how freezer equipment would be with it in a position not usually intended for it. Know what I mean?

If it's works good I probably will be doing this soon for a big ol ferm chamber

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I get what you mean and I think it will be able to maintain proper temps at both freezers.
Right now I have 10gal of sweet stout fermenting in 2nd freezer, after racking I"ll be able to finish collar do the test ride...
 
I get what you mean and I think it will be able to maintain proper temps at both freezers.
Right now I have 10gal of sweet stout fermenting in 2nd freezer, after racking I"ll be able to finish collar do the test ride...

Considering most modern chest freezers get down to -20F or colder when left on, you should have no problem keeping the freezer at 40ish and the ferm area between 40-60F for fermenting...
 
I meant is the freezer making any weird noises or not sealing right since you have turned it vertical rather than how a normal chest freezer would sit. That is a chest freezer on its side right.? Just making sure I gave my facts right.
 
No, fermentation chamber is old broken freezer from which I removed compressor, so it is not in function.

Considering most modern chest freezers get down to -20F or colder when left on, you should have no problem keeping the freezer at 40ish and the ferm area between 40-60F for fermenting...

I bought used freezer (for keezer) and I told the guy to turn it on day before I went to check it.. it was -20C when I came.. pretty good for used freezer, with 4" thick sides I don't expect huge problems with maintaining temperatures.
 
I mounted fan into reducer, it was pretty easy.. only problem was that a fan is bigger than coupler, but that can be solved by cutting two corners of fan.
Since fan has holes for screws I drilled reducing coupler and screwed fan on it (with nuts), after that I cut styrofoam to match gap and inserted it between fan and coupler, covered it with silicone and viola..

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I got one issue so please if anyone could help me out with it: my freezer has controls mounted on lid and since I am making collar with embedded controller on it (STC-1000), I do not know how to override the original controller and wire new one.

Also, I cant install collar because of two cables that goes from lid (controls and light), controls cable goes into switch next to compressor and other one (light) goes into freezer (!!?) I really don't know why.. maybe I missed something but it makes no sense to me since there should be some connection with AC power and I don't see it..

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White cable that comes from outside is power, 2nd white cable under it is control cable that goes to freezer lid, and I don't know what for is black cable... maybe for capacitor?
Other white cable (on top) that goes into freezer is light..

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I assume I"ll have to cut wires and re-solder them but there are too many wires and it would be pretty PITA.. any ideas on how to solve it easily than that?
 
The project continues... I cut and re-soldered wires, if anyone have this model (Liebherr GTS 2563) this is how wiring goes:
3 wires comes from compressor to control panel, panel has 7 pins: 3 are income from compressor, 2 are for light and other 2 goes to thermostat.

I removed lid and started with collar construction, holes on side are for air income/outcome from fermentation chamber, two in front are for taps.. It was tough to find 2x6 wood here so I decided to go with 2 pieces of 2x3 attached together.

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Collar sits well on freezer, I still have to make outer frame..

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Collar is finished.
It was pretty PITA to adjust height since I made it from two wood rods- they where raw when I bought them so I had to plane them with plane machine which caused small (but irritatingly) height unevenness..

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I planned to use liquid nail but it sits on top of freezer pretty tightly so I will leave it this way.. there is no chance to move it.

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Corners and small gaps between wood and freezer are sealed with silicone.

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Next step is to make inner insulation frame from styrofoam board and put some weather strip on top of collar to provide better lid sealing.

I thought I might cover the lid (or at least front of it) with some sort of wood panels to overlay ugly holes from controller unit in front.
 
Sorry mate, suppose I had to put line "don't read if you"re in hurry" in thread title :)
 
I put styrofoam insulation around collar and glued it with silicone, small gaps are also filled with silicone.

Luckily, I found some PVC board near the road (thrown as garbage), I cleaned it and used it to cut 4 strips and mount it on collar to ensure that lid is sealing well... seems that this project made me ecologist :)

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I did kind of the same thing and I've had problems. You will get tons of condensation in the freezer and it will be working overtime trying to keep up. I am using one as a freezer and the other as cold storage but the freezer got iced over and quit freezing because of all the moisture. I put a 4" X 25' flexible vent tube in the freezer so the air does not transfer into it, instead the cold comes from the tubing.

Here is the build thread, I will take pictures of the mods and post those up also.

https://www.homebrewtalk.com/f51/new-life-dead-freezer-308336/
 
Second freezer (positioned upright) will be for ale's fermentation not for cold storing like your, due to that I think the keezer will be able to maintain both temperatures without huge problems, but that still needs to be checked out.

As for condensation, I see that as risk of project. If it works at first great, if not that is just sign that it needs further modification.
I'll try to seal all possible gaps, that is why I put styrofoam frame inside of collar and pvc stripe on top of it to ensure better lid sealing. If needed I will install fastener with spring on keezer lid as I did with other freezer.
 
If you do have condensation problems you can use the 4" duct and it will solve the problem. My keg storage area stays in the low 50's and my freezer is below 0.
 
How freezer acts with maintaining that temp. difference, does it turn off over time?
Also, do you circulate cold air from bottom to bottom?
 
I take from the bottom of the storage chamber (coldest air) it goes through the freezer in a 4" duct and comes back out on top.
 
I think I'll go with different approach- cold air from bottom to bottom and warm air from top to top.
My logic is this: if air circulates from bottom to top and vice verse, fan will suck cold air from bottom of fermentation chamber and blow it into top of keezer, and i think that is less effective since we want cold air to stay in fermentation chamber.
Advantage of different approach is better circulation (air circulates crosswise, like number 8), but I think that circulation will still be adequate with bottom-bottom and top-top approach...

Correct me if I am wrong.
 
Ok, time to show up this baby..

1st pour of milk stout is out and it tastes great.. :)
5.5 ft of 5 mm ID tubing does the job.. it is well balanced with no excessive foaming and nice flow.

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I'm missing one part of another tap so for now there will be only one choice to enjoy, but sweet one.. :)
Fan is wired on keezer input so it works when keezer is on.

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Air between keezer and fermentation chamber circulates this way: there is pipe reduction in keezer with fan in it, this fan sucks cold air from bottom and blows it in chamber's bottom, other fan circulates warmer air from top of chamber to top of keezer.
It works like a charm and keezer doesn't have problems with maintaining both temperatures, it is mostly off once temperature is achieved..

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Old freezer in new role with 1st batch of Christmas ale.. so far so good.

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I will monitor humidity and see if future modifications are required.
If not, I think I'll take a rest and enjoy in kegged beer for now.. next mission will be editing keezer's lid, maybe wood cover, paint or something else.. idea will come eventually.. with taped beer I doubt it will be tough to think of something about it.. sweet worries:)
 
Nice build, some great thought put into it. I think that freezer lid wired with controls might have stumped me.

If you get some moisture problems these things are cheap and work great. My keezer's been dry since I got it.
 
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Thanks.

There is some condensation but mainly because of old freezers's lid (one on left side) which doesn't seal well. It is old freezer (I think from 70's) and rubber seal is became rigid, also freezer is not intended to sit vertically so lid has little gap on left side. Right side seals really good because of door fastener.
I'll have to put some insulation strip and maybe find out another solution for tightening the lid.

I was thinking to use something like hood latches that are used on race cars to secure bodywork, something like this:
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or
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That is real cool.

Still work okay?

I happen to have a spare vertical kitchen type fridge in my garage... I kept it after upgrading the appliances.

Anyway, is it possible to get the standard fridge to maintain temps as high as 65 degrees for fermenting?
 
Sure, beer on tap on one side and fermentation on other.. keep the line :)

I don't see reason why it shouldn't work, heat it with hairdryer, bulb or other heat source, it should be fine..
 
Sorry if you mentioned it and I didn't see, are your fans temp controlled? I want to do this project, I have a Johnson controller already for the keezer as I think I would like to have the intake fan wired to run with temperature control. I plan to build a ferm chamber, I have a son of fermentation chamber that has 2 inch insulation foam that I'm going to scavenge.
Any advice on how to wire a computer fan to the $20 temperature controller you linked?
 
Also, have you noticed if the keezer struggles to keep the ferm chamber at a low enough temp? Do your air circulation fans have to run instantly since the keezer is at 40?
I would like to do this, I live in michigan so even in the summer my basement is pretty cool. I just wonder what the max difference below ambient the hammer can maintain without blowing out the chest freezer
 
Yes, fans are controlled by STC mounted on ferm. chamber.
As for wiring, I can't remember but you'll get scheme with controller.

Keezer has it own controller, set for serving temperature.
I usually serve at 45 and ferment @min 59, so it can easily maintain ferm. temps.
 
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