If you wish to adjust the displayed temperature up or down, there is calibration feature in your thermostat. Although it is factory calibrated and should not need to be changed, you can adjust it to match a different thermometer in home.
For example: Putting this adjustment to – 2 will lower the display temperature by 2 degrees. Putting this adjustment to + 2, will increase the displayed temperature by 2 degrees.
The maximum amount you can calibrate the thermostat is plus or minus 5 degrees Fahrenheit. (plus or minus 3 Celsius)