Why is my heating or cooling system not responding to the thermostat?

Verify that the system mode is set correctly—press SYSTEM to set Heat and ensure the temperature is higher than the indoor temperature, or set Cool and ensure it's lower. Also check the circuit breaker and reset if necessary, confirm the power switch at your heating/cooling system is on, and make sure the furnace door is closed securely. If 'WAIT' is displayed, wait 5 minutes for the compressor protection timer to finish.