Why Does My Furnace Fan Keep Running in Big Stone Gap, VA?

Your Big Stone Gap, VA, furnace fan should only run during active heating cycles. A fan that’s continually running indicates that there’s either a problem or an improper setting. Consider the three reasons that may cause your furnace fan to keep running.

Thermostat Setting

Your thermostat has a switch that controls how the fan operates. In most cases, you want it set to “Auto,” which makes it run only during heating or cooling cycles. Once the home reaches the desired temperature, the fan should shut off.

However, there’s also an “On” option, which makes it run all the time. It’s a good option if you need to keep air moving throughout your home for a period. Checking your thermostat will let you know if your fan isn’t stopping because of the setting.

Fan Limit Switch in Manual Override

The fan limit switch has two separate important functions it performs for your system. First, it controls when the blower fan motor runs during a normal heating cycle. It also acts as a safety mechanism that will shut down the burner to prevent overheating.

The switch has two modes: auto and manual override. With the manual override activated, the fan will continue running all the time.

To check it, locate the white button or knob under the furnace hood. The button should be out to keep it in auto mode. If it’s depressed, pull it out, and it should reset to auto mode.

Faulty Component

There’s also the chance you have a faulty component. The first place to look would be the fan limit switch. A short in the thermostat wiring could also cause the fan to run continuously. A service technician will routinely check for these during a furnace maintenance visit.

Letting your furnace fan continually run will increase your electric bill and wear your motor out prematurely. Call to schedule your furnace repair with NATE-certified service technicians at Mid Mountain Heating & Cooling today.

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