5 Air Conditioner Sounds Your System Should Never Make – Sobieski Services | DE, NJ, PA, MD

5 Air Conditioner Sounds Your System Should Never Make

Many air conditioner noises are normal, such as the whirring compressor and humming blower. Other sounds, such as squealing and grinding, can be unsettling, especially on hot summer days when you really don’t want the air conditioner to fall out of service. If your air conditioner sounds like it needs help, try these troubleshooting tips.

High-Pitched Squealing

A temporary high-pitched squealing noise from the blower compartment on startup is normal. If the squealing continues during operation, you may have a loose or frayed belt, or the pulleys may be out of alignment. A professional can tighten or replace the belt or use a level to align the pulleys.

Rattling or Banging

Rattling or banging noises usually indicate a problem with the blower assembly or blower motor. Rattling means a part is loose. Banging means a part, such as the motor mounts, has disconnected or broken. Turn off the A/C and call your HVAC technician.


Sound It’s easy for objects such as sticks or other debris from the roof to fall into the outdoor blower assembly. If you hear a thwapping sound similar to a card in bicycle spokes, there may be something stuck in the outdoor fan.

Buzzing Sounds

Buzzing sounds and an air conditioner that won’t start may indicate a faulty capacitor. The capacitor is located in the electrical compartment of the outdoor cabinet.

Grinding Noises

Grinding noises indicate worn motor bearings or a failing blower motor. No matter the diagnosis, turn off the air conditioner and call your HVAC technician. Don’t run the air conditioner until the problem is resolved. Once you’ve inspected air conditioner sounds, cut power at the indoor thermostat and outdoor pull fuse box if you’re going to work on the system.

At Sobieski Services, Inc., our goal is to help our customers in Delaware, Pennsylvania, Maryland and New Jersey learn more about energy and home comfort issues – especially HVAC and plumbing issues – so that they can save money and live in healthier, more comfortable homes.

Photo Credit: electricnude via Compfight cc

Service Coverage Map

Check Out Our Incredible Offers!

Book Now