Why is my AC unit turning on but the fan does not spin?

Author: Lizeth Nicolas  |  Last update: Sunday, January 25, 2026

If you see the AC fan not spinning, the fan motor may have burnt out. If the fan motor has been working very hard and hasn't received regular annual or biannual maintenance, motor bearings can break down. Fan motors can be quite pricey to fix or replace. You may end up having to replace the entire system.

Why is my AC running but the fan not spinning?

If your air conditioner is running but the fan isn't spinning, it could be due to a faulty capacitor or a problem with the fan motor. Check the capacitor first for any signs of damage or bulging. If it looks okay, it's likely an issue with the fan motor itself.

Why is there no fan when AC is on?

Yes, you want the fan to run anytime the A/C is on. That is how the cold air gets blown into the space. Many A/C systems will kick the fan on automatically, but not all A/C systems will do this. Therefore, it is always best to have the system fan on whenever the A/C is on.

Why is my AC not blowing but the fan is running?

If the AC compressor is not working but the fan is running, potential causes include a faulty capacitor, electrical issues, low refrigerant levels, or compressor failure. It's best to consult a professional HVAC technician to accurately diagnose and repair the problem.

Why does my fan motor run but not spin?

  • Why does an electric fan make noise but does not spin?
  • Either the motor armature is binding/stuck or the auxiliary winding (start winding) or its capacitor is bad.
  • Don't operate the fan in this condition.
  • Take it to a qualified technician or replace it.

How to fix your AC: fan not spinning

How do I fix my cooling fan not spinning?

Step-by-Step Guide to Troubleshooting a Non-Functioning Radiator Fan
  1. Check the fuse. If the fuse is burnt, replace it with the same size and type. ...
  2. Inspect the fan's condition. ...
  3. Test the fan motor. ...
  4. Check the coolant temperature sensor. ...
  5. Test the fan relay. ...
  6. Trace the wiring.

Why is my AC unit humming but not spinning?

The outdoor AC unit is humming like normal, but the fan isn't spinning, and you hear a buzzing noise coming from the unit. If this describes your situation, you most likely have a bad fan capacitor. A damaged capacitor will prevent the AC fan motor from receiving power.

Why is my AC fan not kicking on?

An outside AC fan not spinning could be caused by power supply issues, a faulty capacitor, a burnt out motor, contactor issues, wiring problems, debris or obstruction, a faulty thermostat or control board, or frozen evaporator coils. Contact your local Carrier dealer to help troubleshoot the issue further.

How to tell if an AC capacitor is bad?

A sure sign of a bad AC capacitor is a humming sound from within the access panel. Any humming noises indicate a problem with the air conditioning system or the components of the AC unit. Try turning the power on and off again to see if it was a one-time issue with the motor or a recurring problem.

Where is the reset button on an AC unit?

Power down your AC: Turn off your AC unit and unplug it from the power source. This will ensure that you stay safe while working on the unit. Locate the reset button: Most air conditioning units have a reset button located near the outside unit. It is usually a small button located inside a small hole.

Can an AC still work without the fan?

No, the pressures will build and go off on high limit or ruin the compressor. Also the coil will freeze. The system must have the condenser fan operational to work properly. Except when a low ambient kit is used for AC systems to work in colder applications.

How do I know if my AC fan is broken?

7 Signs and Symptoms of a Bad AC Fan Motor
  1. AC Fan Doesn't Start. Even though you have the AC turned on, the fan does not start.
  2. AC Fan Doesn't Stop. ...
  3. Slow Rotating Blades. ...
  4. Outside Fan Blades Are Still. ...
  5. Rattling, Humming, and Buzzing Noises. ...
  6. AC Runs Intermittently. ...
  7. No Cold Airflow.

Should the fan be running when the AC is on?

Keeping your fan on AUTO is the most energy-efficient option. The fan only runs when the system is on and not continuously. There is better dehumidification in your home during the summer months. When your fan is set to AUTO, moisture from cold cooling coils can drip and be drained outside.

Should I turn off my AC if the fan isn't spinning?

If you don't turn off the power to your AC, you run the risk of heating the unit's compressor past its limits as it attempts to cool your home without a functioning fan. If the fan doesn't start to spin on its own, it might be more than a bad start capacitor or contactor.

How much does it cost to replace a fan motor in an AC unit?

The average cost of a new condenser fan motor ranges between $300 and $700, depending on the model, your AC unit, and labor costs. While this isn't cheap, replacing your fan motors before they break can save you thousands of dollars in HVAC repair services.

Why is my fan not blowing air?

This can be caused by a variety of factors including a blown fuse, loose wiring, a problem with the dual or single capacitors, or a defective motor. If you suspect that your ceiling fan has electrical issues, you'll need to have it repaired by a qualified electrician.

How do you reset an AC capacitor?

It's a small, red button usually located on or around the unit. The button should have a clear 'reset' label. Once you find the button, press it for around three seconds and observe the AC. Check whether the AC kicks on immediately and if it doesn't, press the button again for another three seconds.

Will the fan still run if the capacitor is bad?

If your HVAC capacitor is bad, the motor will run at higher amplification, run backwards or stop running altogether.

What is the most common part to fail on an AC unit?

#1 Most Common Air Conditioning Repair – Bad Capacitor

The fan of course makes a whirring noise, the compressor is like a deep buzz like a refrigerator running. Holding your hand above the fan should feel warmer than the outside air.

Why is my AC running but fan not spinning?

If you see the AC fan not spinning, the fan motor may have burnt out. If the fan motor has been working very hard and hasn't received regular annual or biannual maintenance, motor bearings can break down. Fan motors can be quite pricey to fix or replace. You may end up having to replace the entire system.

How much does it cost to replace a capacitor on an AC unit?

The average cost to replace an AC capacitor is $180. Prices usually range from $200 to $400 depending on the type of capacitor and system you have. Photo: Courtesy of Angi member Kathy W.

Why is my fan motor not spinning?

If the motor hums but doesn't run, and if it's hard to turn, its because the bearings are seized. If it hums and turns freely but doesn't run, then it's probably the capacitor connected to the motor, and if it doesn't even hum, it's the motor's thermal fuse, switch, or power cord.

Why is the fan not kicking on my AC unit?

One of the most common reasons why your AC fan is not spinning is because the thermostat is not set correctly. Be sure the system is set for cooling and not heating and then switch it back to cooling or auto mode and check that the appropriate cooling temperature is selected.

How do I know if my capacitor or fan motor is bad?

Signs of a bad AC capacitor include humming noises coming from the unit, slow starting or stopping of the fan motor, and frequent cycling on and off. AC capacitor troubleshooting should begin with checking for any visible signs of damage such as bulging capacitors or leaking fluid.

Why is my fan making noise but not spinning?

Your ceiling fan is humming but not spinning because there may be an issue with the capacitor, which is responsible for providing the initial jolt of electricity needed to start the fan blades spinning. Another possible cause could be a jammed motor due to accumulated dust or dirt.

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