1. I need a larger chamber since I am making a lot of bread these days.
2. I am often fermenting around 60-65F and proofing around 70-75F. The peletier-cooled models I have tried are often unable to handle the high local ambient temps.
3. A refrigerated and heated chamber the size I want can cost several thousands of dollars - more than a nice trip to Naples. Screw that!
4. I have an old wine refrigerator I picked up several years ago at a garage sale that I sometimes use for curing charcuterie. It's built-in temp control is squirrelly.
5. So I picked up a pair of these temperature controls:https://www.amazon.com/gp/product/B0015NV5BE/?tag=pmak-20
one for a heat source and one for the cooling. I did a lot of research. There are cheaper and more expensive. These can control both heating and cooling devices. They don't come with standard A/C plugs, but with some cannibalized power cords, wire strippers, and some staring at the circuit drawings, I had them both wired-up in about 30 minutes.
One of the controls is configured for cooling; the refrigerator's power cord is plugged into it. The other is configured for heating and is connected to a little heating pad that I use for warming seedlings; it is inside the fridge. A small fan inside the fridge distributes the air.
After powering everything on, I was expecting a certain bounce, but when it reached the set temp of 60F, the fridge powered off and the temp just stayed there. If I open the door, the temp rises a few degrees, but gets back down to 60F in a few minutes and just stays there. Very pleased. Since the ambient temp in the garage where I have the fridge is about 70F right now, the heating pad hasn't had to kick in at all, so we'll have to see how that works out. Maybe a lightbulb with a dimmer will work better.
I'll post photos once I have drilled a hole in the side for all the wires. It looks like a real mess right now.