- Why an AC fan stops working
- How to fix an AC fan
- When to get help from an HVAC pro
And much more!
So, if you’re wondering why your AC fan isn’t working and want to know how to fix it, keep reading our detailed guide below to get answers to all of your questions!
What Are the Top Reasons AC Fans Stop Working and How Do You Fix Them?
The two fans on your air conditioner could fail for various reasons. The first fan is located on the compressor unit (outdoor unit) and helps remove the heat from the compressor and condenser coils. They both work in conjunction to provide your home with cold air.
If you notice your outdoor fan isn’t running, but your compressor is, you should immediately turn off your air conditioner and give your cooling system a rest until it’s fixed.
Your compressor can quickly overheat without the fan running and cause more damage beyond just a failed fan. A fan is significantly cheaper to repair than a failed, overheated compressor.
The second fan in your HVAC system is located inside your home and blows air over the cold evaporator coils to cool air in your home. If the indoor blower fan fails, it certainly causes discomfort but is less problematic than an outdoor unit fan failure.
The Fan is Set to “Off”
A common reason for indoor AC fans not running is because the thermostat is set to “off” or “fan off.” If you are having issues with your indoor AC fan, double-check your thermostat setting.
Note: There’s no fan setting on thermostats for the outdoor unit fan. This fan will run on demand when the condenser (and AC system) is running.
Faulty or Failed Capacitor
The outdoor unit or condenser of your air conditioning system contains a capacitor that looks like a small metal cylinder. It is wired into a relay and drives the motor of your condenser fan. If it fails, or malfunctions the fan could not run at all, or the fan may start to turn, then stop.
The capacitor is located in the condenser under a metal cover that can be removed with a screwdriver. The capacitor varies in size depending on your air conditioner, but they are typically larger (wider and longer) than a D-sized battery.
To check your capacitor, shut off the power and remove the cover on the condenser to inspect the capacitor visually. A healthy capacitor will be flat on both the top and bottom of the cylinder. A “blown capacitor” usually has a bulge at the top, bottom, or both ends of the cylinder.
If you suspect that a faulty or bad capacitor is the cause of your outdoor fan not running, give our HVAC pros a call. We can schedule air conditioning repair to get you back up and running cool!
Contactor or Relay Issues
A contactor or relay is the switch that controls your compressor. It turns the outdoor AC unit on and off. Contactors can and do go bad over time. So, if your outdoor condenser and fan are not turning on at all, you may have a burnt-out contactor.
The contactor is located under the same panel as the capacitor and is typically right next to it. The contactor provides power to the capacitor, which energizes it and allows it to control the motor.
Burnt Out Fan Motor
Fan undergo a lot of stress. They are running almost constantly on hot days throughout the summer months. If your condenser fan motor is not maintained correctly, it can wear out faster than average and stop working.
If your fan motor burns out, contact a professional HVAC contractor on our team for service to get your motor running. Replacing a bad fan motor is a complex process that our experienced technicians are trained to get done correctly.
Broken Fan Belt
A broken fan belt can happen to both the indoor and outdoor fan of your AC system. If the fan belt is broken, the motor will run, but the fan won’t spin at all. Like many other fan failure modes, this repair is best left to our skilled HVAC technicians.
Broken Fan Blades
Broken fan blades on an indoor fan are a rare occurrence. However, it is a more common issue with condenser fans. Usually, something like a rock, stick, or other debris infiltrates the condenser cover and gets struck by the fan.
The fan striking a solid object at high RPMs could be enough to crack and chip the blade. When one of the blades is damaged, the fan becomes unbalanced. When a fan is unbalanced and spinning, it will wobble and cause vibration. These vibrations can further damage the fan motor and compressor.
A broken fan blade requires a complete replacement, which is where our team of HVAC professionals can help.
Dirty Air Filter
A dirty and blocked air filter doesn’t necessarily stop your fan from working. However, it can certainly make it feel that way since it blocks the airflow. Cleaning or replacing your air filter should be done on a routine basis.
Clean air filters have less strain on the indoor fan and improve the indoor air quality of your home.
Frozen Coils
Frozen evaporator coils on the air handler unit of your air conditioner can also inhibit airflow. However, the coils can freeze if there is not proper airflow across the coils too. So, frozen coils can be both a cause or an effect of your indoor fan not working.
Frozen coils are issues best left diagnosed by our HVAC pros. It’s hard for most homeowners to tell whether there are refrigerant leaks, fan issues, or other component failures causing frozen coils without the proper equipment and training.
No Power
If your outdoor unit is not getting power, the fan on the condenser won’t run. On scorching days, your condenser may be overheating and tripping the breaker. This issue is usually a simple fix. All you have to do is turn the breaker back on in your breaker box.
However, if this issue persists, i.e., the breaker gets tripped often, contact our HVAC pros for a permanent solution.
Other AC Unit Fan Problems
Besides the air conditioner’s indoor or outdoor fan not spinning at all, other fan issues can pop up that require the homeowner’s attention. If your air conditioner’s fan has any of these issues, call us today to schedule a visit with one of our knowledgeable HVAC technicians.
Outdoor Unit Turns On and Off Repeatedly
If your outdoor fan turns on and off often with electrical clicking noises no matter what your thermostat is set to, your outdoor unit likely has some sort of electrical issue. It could be faulty wiring, a shorted control board, or even component failure.
Without proper electrical diagnostic and repair tools, an average homeowner could not fix this problem. Call our HVAC repair professionals to help you get back up and running.
Fan and Compressor Are Not Turning On
If both the outdoor fan and the compressor are not turning on, your outdoor unit is not getting any power. You’ll hear a hum of the compressor if it’s running, but if you hear nothing, either the circuit breaker has been tripped, or the compressor relay has failed.
Slow Spinning Compressor Fan
A slow spinning fan may not provide adequate cooling for your condenser or outdoor unit. If the outdoor fan is spinning slowly and quietly, there’s likely a problem with the capacitor. On the other hand, if it is turning slowly and loudly, then the issue is likely debris in the condenser getting hit while the fan is spinning.
In either case, shut off the unit and have it serviced by an HVAC professional. Our HVAC technicians are trained to fix condenser fans safely and get your unit humming like it’s new.
When Should You Hire A Professional To Fix a Bad AC Fan?
Fixing an outdoor fan and an indoor fan of a central air conditioning and heating system is best left to professionals. Our HVAC technicians have years of training that prepare them to diagnose these types of issues quickly while keeping safety in mind.
They also have specific HVAC tools that enable them to swiftly fix all the issues that prevent fans from working. If your AC fan is not working, please use this troubleshooting guide for a DIY-diagnoses, but if you want superb service in fixing the problem – it’s time to fix your fan for good, call us today.
