W1209 Thermo Controller

Petamentor.com  » Tutorial »  W1209 Thermo Controller

W1209 Thermo Controller

w1209 thermo controller diagram

w1209 thermo controller diagram

The W1209 is so far the cheapest and simplest heat block heating solution for the required temperature. The advantage is that you do not have to be able to program and set up an arduino, although we will also deal with the arduino solution over time. The W1209 was originally designed as a temperature controller such as a chicken hatching incubator. Therefore, it works with temperatures only up to 110 degrees Celsius. The idea is to bridge the temperature sensor input with a cheap Diode 1N5408. This hack allows the W1209 to work at many times higher temperatures.


  • There are a few W1209 models on the market
  • if your module shoving “LLL” replace the polarity of the 100K thermistor
  • If your module has 8 options, set working temperature about 48°C
  • if you have 6 options model, then set working temp at about 70°C

W1209 Wiring diagram

Watch video how to assemby and wire the W1209 module