My last fermentation chamber thread.

So I started working on my chamber.. It took me about 8 hours on Saturday and about 4 hours on Sunday to get where I am at.

Just to recap:

I gutted this mini fridge:



I have ordered a ebay aquarium controller calibrated to Farenheit, (which may or may not be for heat only, I have a question into the seller) If it is, I'll most likely purchase a Ranco temp controller for cooling.

I am using a little under half inch ply wood for the edges as well as 2" foam board for the insulation. In the pictures below everything is dry fitted. Im waiting for more time, before I pull out all the foam, caulk the joints in the ply wood, then glue down the foam board, use silicon caulk to seal and then apply metallic HVAC tape to all seams.

I would love some feedback on where you see issues.

Also, how much of a priority should I make a fan to move air around during cooling?

Thanks In advance!

Here is where I am so far:

Here is the Front View:




Here is a Side View:

What is the bottom chamber for? Just curious.

Also, its up to you, but caulking AND taping the seams kind of seems like overkill to me. One or the other ought to be sufficient, I would think.

My original idea was to store my bottles in there while they are bottle conditioning. I still may do that, but I want to get the top part up and running first. Then I can take my time figuring out how to move cold air to the bottom compartment efficiently.

For now it will probably be for storing my brew tools and equipment.

I'm all about overkill :rockin:

So.. I am a few hard working hours away from completion on phase 1 of the project. And I am thinking of ways to make this really cool. One thing I was thinking is to mount a flat screen to the outside of the door or on top of the the chamber and attach a infrared camera to the inside, so you can see the beer fermenting without having to open the door.

I happen to have an extra small flat screen lying around and I can't really think of a better use for it. My only question is how the hell do I go about doing this?

I was thinking I would just need to find a cheap camera online with AV plugs that I could just connect directly to the TV. Although with a quick internet search, I haven't been able to find one.

Does anyone know of a way to do something like this?

You may be able to do it with a wireless connection. Will it be at all close to your computer? If so, and your graphics card has dual monitor output, you could just run an extra line from your computer to the monitor, and then use a wireless camera.

It looks like your chamber size is over 4x of the original fridge size. I am curious how well it will work and how often it will be cycling. I went with about 2x increase in size and thought that was pushing it. When I do lagers it's on a decent amount of the time, but if you are only doing ales you may be fine.

As for sealing up the insulation, go overkill now and you won't have to worry about problems later. Any place where you don't have a full seal and the full thickness of insulation will transfer heat into the chamber from the ambient air more easily. I used expanding foam to seal up the insulation.

Using a fan will help prevent ice buildup on the heat exchanger. I have mine wired up to run only when the compressor is on and it's located in front of the heat exchanger.

I would resist the temptation to mount any heat generating device to the outside of the box like the LCD you are talking about. The hotter the outside of the box is the harder your compressor is going to have to work and I already think you have an underpowered compressor.

oh man.. now I am a little freaked.. I didn't think it would be that big of a deal as I'm only trying to ferment at temps around 60-70 degrees. I may try to lager depending on how stable the condenser is at ale temps.

Definitely answered the question about where to store this though.. I'm moving it inside where the ambient temp isn't so high. If I have to replace the compressor and heat ex changer.. It's gonna be an almost total tear down...

I am also using 2" foam, Using spray foam to fill in the cracks, caulking and then using HVAC tape for the seams. Also the pictures are a little misleading.. I'd say the area I am trying to cool is maybe 3x the size of the fridge, but you are right.. fundamental miscalculation on my part.. and it could cost me.

Anyways.. the temp controller should be here any day now, and I am finishing up the door on Saturday.. I'll post some complete pics when it is done.

Hey, I'm planning on doing something very similar. May be starting the build this weekend. I am using a small dorm fridge, which could not actually fit a fermenter inside because of the compressor hump. I'm building the ferm chamber to be able to hold a minimum of 4 fermenters.

As long as you insulate it sufficiently, I don't think it should be a major issue. No, it wasn't designed to cool that large of a space, but other than making the compressor run a little longer than normal each time its on, it shouldn't be too big of a deal imo. YMMV though.

Another thing to consider in regards to the compressor overworking, is where is it being used? If its in the garage, where the temps can vary greatly, and get up to the high 90's in the summer, it will be working a lot harder to cool than a unit that is being used inside an air conditioned house that never gets over 80F, if that.

Also remember, these fridges are designed to cool down into the mid 30's F. We're only using them to get into the low 60's, maybe the low 50's every now and then. You're only talking a 15-20 degree differential from ambient. The fridge may have to cool more space, but it doesn't have to keep it as cool as normal operation. I think the two things will help to balance each other out.

I agree that if it is well insulated and you are only doing ales then you should be fine. But if you are doing lagers then you are getting down into the 30s or 40s and making too large of a chamber will prevent the compressor from being able to reach those temps.

Before I built mine I looked at plenty of build threads and I did find a few where some took one of the smaller fridges and built a chamber to hold 5 or 6 fermentors and it couldn't get it into the 50s and it was having ice buildup problems on the heat exchanger. That is why I do think that there is a limit to how much you can increase the capacity of one of these.

I am very curious to see how low you can get this guy to go and if you get ice build up on the heat exchanger without a fan.

I'm going to add a fan after reading this... I should be getting my temp controller in the mail today... So I will get it up and running this weekend and do some testing.

I will update the thread with my results.

BeardedIdiot said:

Another thing to consider in regards to the compressor overworking, is where is it being used? If its in the garage, where the temps can vary greatly, and get up to the high 90's in the summer, it will be working a lot harder to cool than a unit that is being used inside an air conditioned house that never gets over 80F, if that.

Also remember, these fridges are designed to cool down into the mid 30's F. We're only using them to get into the low 60's, maybe the low 50's every now and then. You're only talking a 15-20 degree differential from ambient. The fridge may have to cool more space, but it doesn't have to keep it as cool as normal operation. I think the two things will help to balance each other out.

Click to expand...

Thanks Bearded.. that was my original thought when I purchased the fridge that I did. Well see how it goes.. can't wait to get this temp controller and build the door. It's going to be a fun Saturday!!

So here is where I stand so far.. Sorry for the picture quality, I took it with my phone and did not realize it was so terrible.

I will post some better ones later.

I hooked up all the wires and got it running. I've actually got a Caribou Slobber fermenting in it right now.

Still need to finish up some cosmetic wiring and make things a little more pleasing to the eye... but this is pretty much the finished product.. Going to paint the door with some chalk board paint to label each carboy on the outside.

So whats the verdict? Did you finish it? How does it perform?