Another Fermentation Chamber Build

I've recognized that, where I currently ferment, I have very poor temperature control. The consensus seems to be that proper control of fermentation temp is one of the best things I can do to improve the quality of my beer. So, I decided to start this build.

I have a 7.5 gallon Stout Tank SS fermenter, and wanted to make a chamber large enough for this, as well as leaving additional room for bottle-conditioning beer or adding a second fermenter at some point. So far, I've made only ales, but am hopeful I'll be able to hit lager temps, or cold crash in this chamber.

To keep weight down, I framed this out with some 3/4" pine, ripped to 2" wide. This creates the space for 2" of R-Max foil-face foam insulation.

















I left an opening on one end to attach the dorm-sized fridge. I opted to do this so that, in the event the fridge fails, I can easily replace it.


The large door is where my SS fermenter will go. I'll install a pull-out shelf here so that I can slide the fermenter out to harvest yeast, add hops, etc.



I'm going to clad the whole thing in 1/4" plywood, gluing the R-Max to it as I go. Then I'll install a second layer of 1" R-Max (local HD is out of stock right now...) on the inside to cover all the seams and add additional insulation value.

I got all the plywood on the outside yesterday and wired up my controller to test. I'll have an outlet mounted on the outside on the fridge end for cooling, and two outlets mounted inside; one for heat and one always on (for a fan, light, etc.).

I am interested to see how this turns out, whether you can hit lager temps or not with how big this is. It's what something like 4x4x3' so ~48 CF without the mini fridge? With a mini fridge you are talking 52 CF, so you are increasing it by 13x. I thought I was pushing it when I built mine by taking it up to 10 CF with a 4.5 CF mini fridge.

Yep, that'll be a stretch, I know. Outside dimensions are 48" H x 42" L x 32" W; subtract 6" each way for inside dimensions (3" insulation) and add a 4.4 cu. ft. fridge. That's one reason I'm going overboard with extra insulation. Hopefully, I'll finish insulating this week and take it on a test run with a fermenter full of water.

Got the doors temporarily hung. HD finally got the 1" R-Max board in stock, so I'll try to get the inside layer installed today.

Hurricane Sandy kept me home for a couple days, so I got all but the last piece of the inner layer of R-Max installed, and got the glides and shelf made for my fermenter. Not pictured, but I also fashioned a couple of door latches. Hope to get this finished this weekend.

It is looking great! Very nice work. Keep the pics coming!

That slide out tray is the bomb. Great idea.

TrainSafe said:

That slide out tray is the bomb. Great idea.

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Thanks. When i was designing this, I was struggling with how to access the lid of my SS conical to dry-hop, etc. Saw these slides at HD for $16, rated for 100 lbs. seemed like a good idea. I'll see how it works next week when I get it all together and test.

scottsr123 said:

Thanks. When i was designing this, I was struggling with how to access the lid of my SS conical to dry-hop, etc. Saw these slides at HD for $16, rated for 100 lbs. seemed like a good idea. I'll see how it works next week when I get it all together and test.

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Keenly interested in your results. I'm planning a similar mechanism on my chamber to allow for 2 vessels lined up. My concern has been the whole chamber tipping forward when it's pulled out. Securing it to the wall would be an easy fix though, I guess.

jlachesk said:

Keenly interested in your results. I'm planning a similar mechanism on my chamber to allow for 2 vessels lined up. My concern has been the whole chamber tipping forward when it's pulled out. Securing it to the wall would be an easy fix though, I guess.

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I have the same concern, so I added some extra weight in the bottom; two layers of 1/2" plywood. If it still feels like it might tip, I have the option, where I'm putting it, to anchor to the floor. When I got the shelf done, I pulled it all the way out and leaned on it pretty hard (mainly to test the slides); seemed very stable. I'll keep you posted on how it goes when I test with a full fermenter.

Great idea with the slide out tray. Well done.

Finished the inside layer of insulation, caulked and taped all the seams. Also added a second layer to the doors and made some latches. Ready to install the wiring and controls next.

TrainSafe said:

That slide out tray is the bomb. Great idea.

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I was thinking the same thing. Great idea!

Started installing the wiring this evening.

Controller mounted on top.



Decided to add a piece of plywood to attach the electrical box, and leave room to add a light and/or fan later. Installed the light fixture for my heat source.




Here's what I'm using as a heat source.

love it

Got it all together and in it's home.





Took the door off the mini-fridge, added some weather stripping to the front and butted against the opening. I'm using a couple of cheap tie-down straps to keep it snug against the wall of the chamber.




I put about 6 gallons of warm water in my fermenter and tested out the pull-out tray. The glides deflect downward a little, but the chamber does not tip forward at all. Glides function smoothly with the weight.




Time to test it out. I dropped the temperature probe into the fermenter full of water. At 5:15pm, 37.2 degrees C. I've got it set for 20 C; will see how long it takes.

Next morning, down to 19.5 C, heat on.





I watched it this morning, and it got down to 19.4 (set for 20) before the temp started rising again. I'll be very happy if I can maintain temp to +\- .6 degree! I'm also going to pick up a cheap fan to put inside to keep the air circulating.

If you put a fan in there it will tighten up the control. You are experiencing overshoot. Since you don't have a fan yet there was a temp gradient between the minifridge and the temp probe. Once the temp probe got down to 20C the minifridge was colder at that point. After the minifridge turned off the temp equalized in the chamber somewhat and got the probe down to 19.4. In my chamber I have a fan blowing across the heat exchanger so I get very even temps and doesn't drop more than 0.2F below the setpoint when I have the to probe attached to the side of the fermentor.

Now the next test to run once you get your fan in there is how low can it go? Can you hit lagering temps?

Since you have the conical on a slide, you probably could have gotten away with the chamber being shorter... Looks great though! I need to get to work on one.

Crane - good advice. I stole a small fan from my son that has a spring clamp mount. I'll just clamp it to a shelf on the fridge blowing out into the chamber.

I need to see how low it will go, but where I have it, ambient temp is about 50 F right now, so it wouldn't be a great test. Will try when it warms up. I do know that I can easily hold 20 C (68 F), so ale fermenting is definitely a go.

I need to brew...

TBaGZ said:

Since you have the conical on a slide, you probably could have gotten away with the chamber being shorter... Looks great though! I need to get to work on one.

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I could've made it just a little shorter, but I wanted to make sure I have enough room for a blow-off tube or airlock, so I left a little extra head space.

After a couple days of testing, I added a fan inside to keep constant air circulation. I had a cheap A/C fan that has a spring-clip mount on it, which I just clamped to one of the shelves in the fridge, blowing out across the chamber.

Yesterday evening, I set the controller for 10 C, or 50 F, to see if I can hit lagering temps. This morning, the chamber is holding at 10 with an ambient temp of 70F.




I'll let it hold here today, then set it to about 3C to see if I can get it down to cold-crash temp.

Wow this is awesome. How much did the total supplies run you if you don't mind sharing? I'm assuming this lives in a garage or someplace outside of your "living area"?

mforsman said:

Wow this is awesome. How much did the total supplies run you if you don't mind sharing? I'm assuming this lives in a garage or someplace outside of your "living area"?

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Thanks!

I honestly didn't keep track of cost, but my estimate is around $280. That includes the fridge, which I bought used, the controller, most of the wood and electrical materials. There was some wood, electrical and misc. stuff (caulk, glue, fasteners, etc.)that I had laying around that went into it.

I have a detached building in my backyard with a semi-finished loft upstairs. This is where it currently resides, along with my other brewing supplies.

Well, I let it run for about a day and a half set at 4C. It looks like it's bottomed out at 7.2, or about 45 degrees F. Not as low as I'd like for cold crashing, but not too shabby.

Now, I need to brew something to give it some real work.

Nice job! Have you tested the heating aspects of this yet? I'm looking to build a chamber soon and was wondering if a reptile heat light was enough.

Thanks,
Mike

Here's what I'm using for heat. These emit almost zero UV light that would skunk beer, and are less than half the cost of the ceramic reptile heaters.




During a recent cold spell, I was testing with the probe in my fermenter full of water. With an ambient temp around 50F, this easily maintained 70F.

scottsr123 said:

After a couple days of testing, I added a fan inside to keep constant air circulation. I had a cheap A/C fan that has a spring-clip mount on it, which I just clamped to one of the shelves in the fridge, blowing out across the chamber.

Yesterday evening, I set the controller for 10 C, or 50 F, to see if I can hit lagering temps. This morning, the chamber is holding at 10 with an ambient temp of 70F.

I'll let it hold here today, then set it to about 3C to see if I can get it down to cold-crash temp.

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What are your thoughts on that controller? I saw it was listed on homebrewfinds.com at a price of $20. That's an insanely good deal for a dual stage controller that made me think perhaps its too good to be true...thoughts?

https://www.homebrewtalk.com/f51/ebay-aquarium-temp-controller-build-163849/

Most rave about them. I just got one on the way a couple days ago.

My eBay controller works great.

rudzy17 said:

What are your thoughts on that controller? I saw it was listed on homebrewfinds.com at a price of $20. That's an insanely good deal for a dual stage controller that made me think perhaps its too good to be true...thoughts?

Click to expand...

I love it. It's cheap, easy to set up, has aside adjustment range. I ordered two of them a while back for $23 each, including shipping. At that cost, they're hard to beat.