What do you do when your furnace blower won’t turn off? Whether the furnace itself is still going or the fan is just blowing cold air, it’s a big problem that’s wasting a lot of energy. Here are a few potential causes of a nonstop blower and what to do about them.

Thermostat Settings

Getting your blower to turn off could be a simple matter of adjusting your thermostat. Try lowering the temperature. If it’s set too high, your furnace will have to work harder to bring your home up to temp. In the meantime, it will keep running, wasting energy and driving up your bills.

As a rule, keep your thermostat set to 68 degrees during the day. If it’s properly set but it still won’t turn off, call your HVAC technician to make sure the temperature reading is accurate and then recalibrate it if necessary.

If the blower is going but the air isn’t hot, check the thermostat’s “Fan” setting. If it’s set to “On,” air will continue circulating even when no heat is being generated. Set it to “Auto” and wait. It should turn off when your home reaches the set temperature.

Other Nonstop Blower Issues

If neither of these fixes stops your nonstop blower, the problem might be the fan-limit switch on the furnace itself. It’s designed to turn the blower off if the unit gets too hot. Check under the furnace hood for a small white button. If it’s pushed in, then it’s set to manual override, which keeps the fan going. Pull the button out to reset it and the blower should stop.

If it doesn’t stop or if the button wasn’t pushed in, then the switch might be faulty. There may also be a bad wire in your thermostat or another problem. Call your HVAC technician to check it out immediately, as the longer you wait to have the problem fixed, the more energy you’ll waste thanks to a nonstop blower.

For help ensuring your HVAC system is running smoothly and efficiently, contact us at Mowery Heating, Cooling and Plumbing. We provide quality home-comfort solutions to Indianapolis.