Noisy Air Conditioner? Find Out What Those Noises Mean – Sobieski Services | DE, NJ, PA, MD

Noisy Air Conditioner? Find Out What Those Noises Mean

An unusually noisy air conditioner is unnerving to hear on a scorching hot summer afternoon. Especially if the sound you hear is an air conditioner compressor noise, you might be looking at a costly repair. Here are some common noises and what they most likely mean:

Banging or clanking

A loose internal part or motor mount could be jostling around inside the compressor. The only repair likely is to replace the entire compressor.

Bubbling or hissing

Bubbling indicates a small refrigerant leak that requires attention. Hissing is the sign of a catastrophic refrigerant leak that should be addressed before you turn on the A/C again.


This could mean the compressor motor is failing. Continual clicking, rattling or rumbling A loose piece of shipping hardware, such as a bolt, could be the source of the rattle. A visible inspection can lead to a diagnosis and provide a simple solution to fix the problem.


Harmful internal pressure can cause this unsettling A/C compressor noise. The compressor should automatically shut itself off if the pressure gets too high, but if you hear a screeching sound, shut it off immediately. Humming accompanied with slow startup This could mean the starting capacitor needs to be replaced or that the compressor motor has seized, particularly if the A/C fails to start up.


A loose fan bearing could be allowing the fan to wobble, or the fan might be hitting a piece of debris that fell inside.


Some compressors emit a squealing noise as part of normal operation, especially at startup. Trumpeting at shutoff Leaky internal refrigerant valves are a likely cause of this noise. If no hissing accompanies the trumpeting, there’s no cause for concern.

To learn more about diagnosing an air conditioner compressor noise, please contact us at Sobieski Services. today. Our goal is to help educate our customers in Delaware, Pennsylvania, Maryland and New Jersey about energy and home comfort issues (specific to HVAC & plumbing systems).

Image Credit: Sara A Beyer

Service Coverage Map

Check Out Our Incredible Offers!

Book Now