Recommendation for Incubator
For incubator, we recommend using our “universal controller" that is faster. For the temperature sensor, K type thermocouple is not accurate enough for incubator application. You need a RTD sensor for better accuracy. You also need a solid state relay (SSR) to interface the heater. This is because incubator normally runs more than 20 days. Mechanical relay is not reliable enough for the job. If it fails in the middle of the process, the loss is too large compared with a $15 SSR.
Here is the list of products that is the minimum for a reliable and working system.
If you want the set temperature also displayed, use this one.
2) Temperature Sensor
Some people like to use the smaller sensor for fast response time. This one can be used.
3) Solid state relay
Here are the links for the forum that discussed on how to build the incubator controller.
Another option for you is to use a plug and play controller.
For 0.1C accuracy