I use a refrigerator modified to cool or heat. I added a bypass thermostat that controls the until with external outlets. Depending on what I am doing in it, I have a ultrasonic humidifier and heat, light bulb or little heater. I can use it as a fridge or warm it up and control the humidity. Right now it running as a spare fridge. I did build this thinking to to proof bread also. But most time I use my small Tupperware temp control to rise dough.