Why Is My Air Conditioner Making Noise?

Man cannot sleep from air conditioner noise

It’s normal for your air conditioner to create some noise when running—that simply means it’s working. Although older units are typically louder than newer ones, not all air conditioning noises are created equal.

Despite your air conditioner’s age, any sound coming from the unit can still be bothersome. If your air conditioner is producing an unusual sound, that could mean trouble. So instead of risking injury to you or your system by poking around the unit yourself, play it safe and call a professional to come inspect it for you.

To avoid any of these potential issues, we at Certified Heating and Cooling recommend getting a maintenance inspection at least twice a year to determine the health of your air conditioner, regardless of its age or noise level. According to ENERGY STAR®, “proper maintenance by a qualified professional technician is one of the most important steps you can take to prevent future problems.”  

Common Air Conditioner Noises

We have heard our fair share of unusual hums, buzzes, and clattering coming from air conditioners throughout the years, so below is a list of the most common noises we have found and the problems they can indicate. Keep in mind, this is for general informational purposes and is not a diagnostic tool. It’s integral to contact us to have one of our knowledgeable technicians come out to diagnose these noises, as they could be a serious issue or a precursor to a serious issue, than when caught early, can save you serious money or even your entire system!

Rattling and Grinding

A distinct rattle could be caused by a loose bolt, screw, fastener, or another small part that fell into the vents. It could also be your compressor or an issue more serious than a loose part. A grinding or noticeable rubbing or scraping sound can mean an issue with one of the fan motors or a broken fan blade rubbing against the motor or AC unit cabinet.

It’s also possible the noise can be originating from a worn bearing or a loose or damaged belt or even a compressor failing. While it’s not typically a griding noise one hears with a failing compressor, not everyone describes sounds the same way. The safest route is always to have your unit checked to make sure the issue isn’t something serious.


A popping noise might be coming from your air ducts when your air conditioner turns off and on. This usually indicates a problem with your ductwork and not necessarily a problem with your central air. Even though these potential problems can be easily confused, ductwork still ages the same as the rest of your your equipment and requires routine maintenance to be sure it’s functioning efficiently and effectively in your home. Scheduling regular duct cleaning and maintenance prolongs the longevity and efficiency of this essential part of your HVAC equipment!


If you hear a hissing, it’s likely this type of noise is generating from within your ductwork, so let one of our knowledgeable technicians take a closer look. We can pinpoint the source and tell you if there is a bigger issue involved, such as a refrigerant leak, where a more detailed repair would be necessary.

Your air conditioner is a complex piece of machinery with many moving parts and, like a car, it requires regular maintenance by experienced professionals like ours at Certified Heating and Cooling to diagnose and treat any potential problems. Don’t ignore the signs if you suspect there could be an issue with your air conditioner. Give your unit the proper attention it needs to operate in prime condition for years to come.

We Want to Help

Trust your ears and judgment. If your air conditioner is making an unusual or harsh noise and you live here in the Fort MyersEstero and Naples, FL, area, call us at 239-205-8342 or schedule your service online today.

Need HVAC Service?

Contact the experts at Certified Heating and Cooling.

Call us at (239) 482-5000!