My heating or cooling system will not turn on at all.

Put the thermostat into the OFF mode. Remove the batteries (if equipped) and press the reset button located on the front of the thermostat. Replace the batteries and move the system switch to the HEAT or COOL position and try running your heating or cooling system again. If the problem persists then you may have a problem with your heating system that is causing it to not operate properly. You may need to call your installer or a local service contractor in your area.