This post is a historical account of my fermentation chamber build from 2011, and includes recent updates. Details of this build are scattered around the web, and now they have been brought together in one place.

About a year after I started brewing, I decided it was time to take the next step in making good beer. As many brewers will tell you, one of the best things you can do is implement some form of temperature control.1 I’d already built my four-tap keezer, and since we had recently moved into a house we had enough room that my wife was OK with me taking up more of it with brewing equipment. I was also stepping up to brew 10 gallon batches on my newly built brew stand, so I needed a fermentation chamber that would easily hold my newly minted fermentor: a sanke keg using Brewer’s Hardware sanke converter kit, and fit two of them side-by-side.

My requirements were clear:

Single stage cooling

Fit two sanke kegs side by side

Front loading to avoid excessive lifting of 10 gallon batches

Fit inside a closet in the den in our house (though it never ended up going in there)

Lets Build a Fermentation Chamber!

The first step to my plan was to locate a mini-fridge form which I could harvest the cooling portion. Newer fridges are built with the cooling coils in the walls, and they would be near impossible to safely dismantle and end up with a usable cooling setup, so my search focused on older units. Fortunately this also meant that the cost would be less, and I found exactly what I needed for $40 on Craigslist. Dismantling the fridge was not as easy as I thought it might be as it was mostly glued together, instead of screwed/snapped as I had hoped. That didn’t stop me for long, however, as I busted out the sawzall and VERY CAREFULLY cut away the pieces of the fridge I did not need to end up with the pieces I did.

With my cooling system safely extracted from it’s previous home, it was time to build the fermentation chamber. After many measurements, and I’m sure more than a few trips to the hardware store, I had the plans laid out for a chamber that would meet my size criteria. Unfortunately I can’t find the plans I drew for it, so you’ll just have to settle for pictures of the build progress instead.

At this point I apparently stopped taking pictures, but the next steps in finishing off the fermentation chamber involved:

Cutting and adhering the insulation board to the wood, using Liquid Nails

Bending the cooling plate to sit vertically and attaching it to the wall with screws through existing holds. I bent the line using a large can of tomatoes to make sure it didn’t kink.

Adding the door. I was previously pictured a one piece, but I realised I wouldn’t be able to open it when it was inside the closet that it never actually went into. I now wish I had left it as one piece and might rebuild the door at some point.

Fermentation Chamber Updates

In 2014 I moved to Michigan, and now required heating as well as cooling. My old single stage Ranco was no longer going to cut it, so I built a dual-stage controller using the popular STC-1000, a tool box to mount it all, and a Lasko 100 Personal Spacer Heater. The controller build included an always-on power supply that allowed me to add a fan that is constantly running, and one that comes on only with the cooling. No extra fans were added for the heater as it has its own built in.

Yes I am aware of recent experiments that may indicate that it is not quite as critical as we might think, but the data sets are small (a stated limitation by the experimenter), and I believe that what we see is more the importance of a consistently temperature controlled environment. My own anecdotal evidence with heavy ester producing yeasts, like WLP300, show that an increase in temperature can produce more of the desired ester if temperature is ramped up over the course of fermentation.