My Outside AC Unit is Humming but the Fan is Not Running

If you’ve noticed that your outside AC unit is humming, but the fan is not running, it’s crucial to take action immediately. This issue could indicate a severe problem with your HVAC system that requires immediate attention from a professional. Together we can explore some of the possible causes of this issue and what you can do to fix it.

Causes of a Humming Outside AC Unit with No Fan Running

• Faulty Capacitor: The capacitor is a critical component of your AC unit that provides power to the fan motor. Over time, the capacitor can wear out or fail, preventing the fan from running while the unit continues to hum.
• Broken Fan Motor: If the fan motor in your AC unit is broken or seized, it won’t be able to spin, even if the unit is humming.
• Blown Fuse: A blown fuse in your HVAC system can also cause the fan to stop running while the unit hums.
• Tripped Breaker: If your AC unit is connected to a circuit breaker that’s tripped, the fan won’t run even though the unit is humming.

What You Can Do

While there are some steps you can take to troubleshoot this issue, it’s always best to contact a professional HVAC technician to diagnose and repair the problem. Here are a few things you can try before calling in the experts:

• Check the Thermostat: Ensure your indoor thermostat is set to “cool” and the temperature is lower than the current room temperature.
• Check the Circuit Breaker: If your circuit breaker has tripped, reset it and see if the fan starts running.
• Inspect the Capacitor: If you’re licensed to work with electrical components, you can inspect the capacitor for signs of wear or damage. If it looks worn or damaged, you may need to replace it.
• Inspect the Fan Motor: If you suspect it is broken or seized, you can inspect it for signs of wear or damage. However, this is a task best left to the professionals.

If your outside AC unit is humming, but the fan is not running, it’s important to act fast to prevent further damage to your HVAC system. While there are some steps you can take to troubleshoot the issue, it’s always best to contact a professional HVAC technician to diagnose and repair the problem. At Premier Indoor Comfort Systems, we have the expertise and experience to get your HVAC system up and running again in no time. Contact us today to schedule an appointment.