DIY Walk in cooler with zones inside

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May 15, 2009
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St. Joseph, MI
I recently built a 3 x 4 ft walk in cooler closet on wheels to ferment in. It has an ac and a coolbot mounted on the top. So far its working fine. My question it possible to keep the fridge at a cool 38 degrees serving temp at all times but still ferment inside it at 62 degrees at the same time? I have 2 carboys and a 12 gallon conical that i put on the floor of the unit and there is a shelf above for other things.

I originally consider trying to just stick the ferment vessels inside some kind of insulated bag with temp controller and a heat lamp. However, i was told from a coolbot expert who said he experimented along those lines and nothing really worked for him. He said the temps just equalized fairly quickly. I was wondering if anyone else had any experience or insight on if and how this could be done.
Partition and add a louver and fan that opens and blows into the warmer chamber from the colder one when the temp of the warmer chamber rises too high. Will need a simple thermostat control device and temp probe. Can easily be done with an arduino board, transistors, servo and computer fan with a handful of other simple parts.
Agree with the insulation board partition. I don't think you need servo controlled louvers or anything. Just a simple styrofoam board flapper door on the top and bottom. One of them gets opened by switching a fan on to blow it open. If you use a 120v fan, you can just plug it into the cooling outlet of an Inkbird 308. The red stuff is just something like tape as a hinge or you can get fancy and use metal hinges just epoxied to the doors.


Yeah I agree with Bobby, servos are a bit overkill and a simple flap is a much more simple and elegant solution. But, overkill and over-complication is a hallmark of a home brewer.
Ok, a little bit of a twist. This is built as an upright fridge style cooler and the partition is separating top and bottom half. Gravity louvres only open if they are mounted vertically i would imagine. I need something horizontal. Any ideas?
There's always a way. Build a small box over the horizontal hole and make one side of it a vertical swinging door. The return probably doesn't need a flap. Air will be less likely to move through one hole.

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