Your furnace has many parts that work together to generate and distribute heat, including a blower fan and motor. If you’re asking, “Why is my furnace blower motor not working all of a sudden?” you’re not alone. Blower motor failure is common, and its resolutions may be simpler than you think.
At Cooper’s Plumbing & Air, we provide top-tier furnace repair in Tallahassee, FL. Consult our guide below to learn why furnace blower motors may stop working correctly and steps you can take to resolve the issue.
What Is the Purpose of a Furnace Blower Motor?
If you have a gas furnace in your home, the system generates heat by burning fuel.
The combustion gases flow through the heat exchanger, which heats its outer shell. The blower fan draws in air from the return vent and blows it over the heat exchanger. This action forces the heated air into the supply ductwork to heat your house.
Your heater can turn on, but its blower motor can still fail. When this happens, the furnace won’t be able to heat your property efficiently.
Common Furnace Blower Motor Problems
If you find yourself asking, “Why is my furnace blower motor not working?” or similar questions, just know that you could encounter various issues that affect the performance of your blower motor. Explore these common issues and their solutions to better understand.
The Fan Runs But Produces No Heat
Sometimes, the problem with a blower isn’t its motor: it’s the furnace’s ignition system.
If the furnace won’t turn on but the fan does, it indicates another problem with the system. The thermostat could be in “On” mode, which keeps the fan running continuously even when the furnace isn’t burning fuel. The issue could also be a clogged filter that makes it harder for the heater to circulate air.
Check the thermostat settings or replace the filter. You may also need to check the furnace’s pilot light and ensure the flame is blue. A yellow, orange, or red flame indicates dust buildup on the burner or incomplete combustion.
The Fan Won’t Turn on at All
Is the fan not turning on after the furnace starts a heat cycle? Damage could affect the blower motor’s functionality. Other possibilities include:
- Incorrect thermostat settings
- Furnace lockout
- Tripped circuit breaker or blown fuse
- An open blower door
- No gas supply
Getting your furnace’s blower fan motor to start could be as simple as ensuring the blower door is shut and turning tripped breaker switches back on. If troubleshooting doesn’t resolve the issue, you need an assessment by a qualified HVAC technician to identify the culprit.
The Fan Won’t Turn Off
It’s not unusual for furnaces to turn off at a different time than their fans. The fan may run for up to five minutes after a heating cycle to keep distributing conditioned air.
If the fan continues running with the thermostat off, the HVAC system may have electrical issues. The problems could be with the fan limit switch, thermostat, blower motor, or furnace control board.
Your first step in troubleshooting this issue is to check the thermostat. Ensure the setting is on “Auto” instead of “On,” which keeps the fan running.
If the thermostat settings are correct, try changing its batteries. You may also need to replace the furnace air filter if it’s dirty, as a dirty filter can cause an airflow obstruction and trigger the heater’s safety switch to prevent overheating.
The Blower Cycles On and Off Too Frequently
Sometimes, blower motors turn on and off too much before the end of a heating cycle. This issue has multiple causes, including:
- Dirty filter
- Dirty flame sensor
- Obstructed return vents
- Thermostat problems
- Triggered limit switch
Inspect your furnace’s air filter to see if it needs a replacement. You should also walk through your house to ensure that nothing is blocking your return vents or registers. Lastly, make sure your thermostat is on “Heat” mode.
How To Test Your Furnace Fan
If you’re still wondering, “Why is my furnace blower motor not working?” after troubleshooting your heating system, you may need to test the blower fan directly.
To do the assessment, turn your furnace off, and then set your thermostat to “Fan Only.” Wait several minutes. If the fan turns on, your heating issue isn’t with the blower motor. The furnace may have a problem with its wiring, thermostat, or another component, which would require a proper diagnosis and resolution by an HVAC professional.
Is It Time To Replace Your Heating System?
Although furnace blower motor troubleshooting and repair can help restore a heating system’s performance and functionality, eventually you’ll need to consider a furnace replacement. A blower motor should last as long as a furnace, which typically has a lifespan of 15 to 20 years.
It may be time to consider a total furnace replacement if your system is 15 years old or older. You may also need furnace repairs more frequently than usual due to worn components and reduced efficiency. If so, it may be more cost-effective to invest in a new heating system than to continue repairing your current model.
If your furnace isn’t approaching the end of its lifespan and doesn’t require frequent repairs, a blower motor replacement may be a suitable option. This choice is usually ideal if the furnace is constantly overheating, which could lead to premature failure of the motor’s electronics. Exposure to moisture can also lead to electrical issues, like electrical shorts, and cause the motor casing to corrode.
Get Help With Your Malfunctioning Furnace Today
If you’re asking, “Why is my furnace blower motor not working?” after troubleshooting your heating system, it’s time to call the experts. At Cooper’s Plumbing & Air, our licensed HVAC technicians have years of experience meeting the heating and cooling needs of residents throughout Tallahassee, Florida. Our team can handle everything from furnace blower motor replacements to loud furnace troubleshooting.
Ready to schedule an inspection for your heating system? Call Cooper’s Plumbing & Air today at (866) 464-7132 to get started.