You may remember my previous posts on my Arduino that switches AC current on and off based on the thermistor sensor reading. After using this for a year, I have ended up changing the switching temperature multiple times based on the season. I decided to add a linear resistor to change the switching temperature.

I started by printing the resistor reading to the serial monitor and found that my resistor sends values of about 100 – 900. I then created seven ranges that the code would switch the temperature at.

While it is still in development, my thermostat switch is quite handy. We use it, mainly in the winter, to switch on a fan when our radiator gets hot. Depending on the time of year and the temperature fluctuation, it is handy to be able to change the temperature it switches at without removing the whole arduino to upload new code.