Normally this would indicate a failed pressure switch, The furnace will test to make sure the switch is open before starting the ventor motor. The contacts in the switch are either stuck together or moisture has entered the switched and seized it in the closed position. The switch will need ...
The fan switch on the thermostat is set to “on” rather than “auto” Relays in the control board are stuck in the closed position, so the blower is getting a constant supply of electricity, and the control board must be replaced
If you have central air conditioning, there will be a separate metal box stuck in with everything else. Just leave it in place, be careful not to break the tubes and wires, and it will continue to work with your new setup. Tools and tips: You cut the metal with tin snips or a gri...