Arduino Thermostat with TC74 sensor

Step 5: Setting Threshold Fan/Heater Values

Now is when the potentiometers come into play.  Connect the potentiometers, with the two ends on 5V and ground and the middle going to an analog input.  Do this for the other appliance's potentiometer as well.

In order to read out what the potentiometer tells the Arduino, initialize the variables and code the following...

fanDigit = analogRead(fanAnalog)/4;
heaterDigit = analogRead(heaterAnalog)/4;

This will give the Arduino a number from 0-255 depending on where the potentiometer is twisted.

This can be used to provide a threshold, with an example of code for the application of a threshold below.

fanThreshold = 20 + fanDigit*10/255;
heaterThreshold = 10 + heaterDigit*10/255;

<more code>
//inside void loop()
if(temperature>fanThreshold) {
        digitalWrite(13, HIGH);
      }
       else {
         digitalWrite(13, LOW);
       }
       if(temperature<heaterThreshold) {
         digitalWrite(4, HIGH);
       }
       else {
         digitalWrite(4, LOW);
       }