How do I switch between Fahrenheit and Celsius on my thermostat?

Access the menu on the PSD111+: Move the Temperature switch to the off position and hold the up and down buttons simultaneously for 3 seconds, or until a menu appears.

1. Press and hold the Up and Down button simultaneously at the F/Cselection.
2. Press Up or Down to select the F or C
3. Once the value is selected, press and hold the up and down buttons to confirm.