Fix Your Never-Ending Furnace Fan Today!

Furnace or A/C not running, but air is still streaming out of your vents? Not sure where to start to address your problem appliance?

Troubles with major household appliances can be especially stressful and frustrating. It’s something you use often, you may not be too familiar with how it works, and you’re just worried things will culminate in a huge bill. Your concern is understandable.

From our experience heating Ann Arbor homes one furnace repair at a time, we have some advice that can help if the trouble is a furnace fan that’s constantly running. Follow the steps below for a potentially simple fix for your major appliance.

1. Check the furnace is not running.

Set your thermostat several degrees lower than its current setting to double-check it’s just the fan running and not the furnace. Wait three or four minutes after changing the setting, listening for the fan to shut off. If the fan stops, you’re all set; if not, continue to the next step.

2. Check the fan setting on the thermostat.

Identify the location on your thermostat where you can change the fan setting, usually a button or switch. Most thermostats have two fan settings, “auto” and “on.” If the fan is set to “on” it will run constantly; if set to “auto” it should only run while the furnace or A/C is running. If your fan is set to “on” change the setting to “auto;” if your fan is set to “auto” but still running, continue to the next step.

3. Check the controls on the furnace unit.

Your furnace may be equipped with a manual override switch for the fan which can keep it running despite thermostat settings. On your furnace unit, locate the fan limit control switch then a push/pull switch which overrides fan settings. Check printing on or around the switch to identify the position the switch should be in. Test the position of the switch to be sure it is set correctly. If the switch was in the manual (furnace-speak for ‘on’) setting, your fan should turn off in a few minutes; if the switch was on auto, continue to the next step.

4. Check the furnace reset switch.

Locate the primary controls on the furnace to see if there is reset button. If an issue transpired which triggered the need for a reset, the reset button may be popped-out (similar to reset button on GFCI outlet). If the button is popped-out, press to reset. If you are unsure if the button is popped-out you can press the button one time to reset the furnace. Do not press the reset button more than once. If your fan continues to run, continue to the next step.

5. Contact Experts on Heating in Ann Arbor

After following the above troubleshooting measures, if your fan continues to run, a wiring or voltage issue is the likely culprit. Tests for these kinds of issues are best left to experts for your safety.

The CMR Mechanical team, heating Ann Arbor homes with a 100% satisfaction guarantee, is ready to help you with any trouble your furnace is causing. Available 24 hours a day, don’t hesitate to call us for an emergency repair or free in-home evaluation. Call us today to whip your fan into shape and leave you with a warm, functional home for the rest of winter!