How to Troubleshoot an Electric Furnace Blower That Won't Shut Off
- 1). Turn your thermostat to the "Off" position. Performing this operation may vary from thermostat to thermostat. There may be a lever on the bottom or side of the thermostat. If your thermostat has a touch screen, it may be an option on that screen. This process could entirely fix your problem because even though you may hear the blower continually running, it may be because your system needs to run that frequently. This is especially true in harsh, cold climates or in homes with little insulation. If your blower turns off after performing this step, you'll know your system is working fine and you can turn it back on.
- 2). Locate the fan switch on the thermostat. If your blower won't stop running, you may notice the switch is in the "On" position. Rectify the problem by switching the switch to the "Auto" position. Once again, if your thermostat is a touch-screen model, this will probably be an option on the screen. Once switched to the "Auto" position, the blower will run only when the thermostat calls for heat.
- 3). Open the furnace cabinet up if the blower still will not stop running. Locate the terminal board where the thermostat wires connect to. If there is a wire connecting the "R" terminal to the "G" terminal, this will energize the blower at all times, and no matter what the thermostat is set to, the blower will not shut off. A wire here may exist because a previous owner or tenant of the property did not have a thermostat with a fan switch and they wanted the blower to run all the time. Simply unscrew the wire from both terminals and discard. The blower will then run only when the thermostat calls for heat. Close the cabinet back up when finished.
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