I'm planning on building a fermentation chamber cooled by a dorm fridge within the next few months. Each chamber would be just large enough for a 6.5 gallon carboy with airlock.
Ideally, it would be dual temp/dual chamber, controlled by 2 ebay temp controllers. The chamber closest to the fridge would be the "cold" chamber, and the chamber further away would be the "warm" chamber. The two would be isolated from each other via plywood/insulation. However, there would be a cutout for a fan in that panel. The one controller would control the cold side (and the fridge) and the other, the computer fan, supplying cool air to the "warm" chamber.
for 2 ales, I'd set both chambers in the 60's
for a lager (or cold crash)/ale, lager would be set lower, with ale in the 60's.
Regardless of what temp chamber 1 is set at, chamber 2 would be set in the 60's for ale fermentation.
Our basement hovers around 60 in the winter, and increases to the mid 70's during summer. Cooling is my main concern.
Is this feasible?