Plans for Oven Incubator

 I use my oven about once a week to bake bread. The rest of the time, it sits unused. I have always wanted a good incubator for making tempeh and proofing bread. But incubators are expensive and take a lot of space. It occured to me I could build a portable converter to turn my oven into an incubator, and then remove the converter when I want to use it as an oven. I have now done this, and I am happy to report that it is very successful. I recently used it for making a batch of tempeh. If you are interested in my directions for making tempeh, you can find them here. 

Basic Design Diagram

Controller

I purchased the controller from Temu. It cost about 5 USD. Here is the link.

Heat Source

The heat source is a 100 W bulb, socket, and wood base. These components came from a local hardware store. I don't remember the total cost, probably under 15 USD. You will also need electrical wires to connect the socket to the output wires on the controller.

Temperature Probe

The temperature probe comes as part of the controller.

Plug

The plug connects the controller to the power source. I don't think it cost more than 5 USD. You will also need electrical wires to connect the plug to the input wires on the controller.

The controller has buttons to set the temperature. You set two temperatures. The low end is when you want the heating source engaged. The high end is when you want the heating source disengaged. When I am making tempeh, I set the low end to 29.5 C and the high end to 30.5 C. When the temperature probe reads 29.5 C or lower, the heating source (100 W light bulb) turns on. When the temperature probe reads 30.5 C or higher, the heating source turns off. So the oven temperature is always 30 C +/- .5 C. 

The nice thing about this design is that it is very easy to place in the oven when you want the oven to be a incubator and very easy to remove when you want the oven to be an oven. To set it up, you just put the light socket and temperature probe in the oven, plug in the controller, and set the temperatures. To break it down, you just remove the light socket and temperature probe from the oven, unplug the controller, and put it away.

This basic design would work well using an old small refridegrator instead of an oven, but an oven is what I have.

You can use this as a temporary tempeh incubator, temporary bread proofer, temporary yoghurt maker, or just about anything that requires a constant temperature for some period of time.