Why is my heat not working?

Last updated

There are several items you can check.
  • First check that the thermostat is set to the Heat position. Make sure the temperature is set higher than the Inside temperature reading.
  • Also check the circuit breaker and reset if necessary.
  • Make sure that the furnace door is closed securely.
  • If “wait” is in the screen or “heat on” is flashing – wait 5 minutes for the system to safely respond.
  • The thermostat will indicate it is asking for the heat to turn on when "heat on" or a "flame" in the display. If this message is in the display, the thermostat is asking for the heat to be on and there is a likely a problem outside of the thermostat preventing the heat from running.
Please see the steps below to troubleshoot this issue:
  1. Verify the call for heat is being made
  2. Check the configuration of the thermostat to make sure it is controlling the equipment properly.
  3. Verify that the thermostat is wired correctly.
  4. Make sure all of the wires are secure and in the correct terminals.
  5. Make sure the voltages are between 18 and 30 VAC or 20 and 30 VAC depending on the thermostat model.
  6. Make sure the thermostat faceplate is firmly in place against the wall plate

For more information on the Honeywell heating and cooling systems, please click here to see a list of instructional videos.


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