Posted by & filed under HVAC

Your central air conditioner can make a variety of noises. While some sounds are normal, others can turn out to be symptoms of an emerging malfunction. Unfortunately, ignoring an unfamiliar noise can lead to a serious and expensive repair. To help you better understand the sounds coming from your air conditioner, we’ve listed 3 noises that can point to a problem with your unit.


A rattling noise usually indicates a component in your air conditioner has come loose. The problem usually lies with either the blower assembly or the motor. Unfortunately, allowing the noise to continue without having it inspected can lead to costly repairs.


When your air conditioner is making a high-pitched squealing sound, the issue most likely stems from either the belt connecting the blower to the motor or the bearings on the condenser fan’s motor. Older air conditioners operate with a belt while the newer units do not. If your A/C is on the older side, and you hear the sound both inside and outside of your home, you are probably dealing with a slipped belt. Replacing the belt should rid your unit of any high-pitched squealing.

Newer air conditioners employ direct-drive motors without belts, meaning the squealing noise is likely coming from the bearings on the condenser fan’s motor. If the sound only comes from your outdoor unit, the motor may need replacing. In order to diagnose and repair the unpleasant noise, call M&M Mechanical, Inc. in Lorton VA today.


A noticeable buzzing noise coming from your air conditioner signals a possible electrical issue. While pinpointing the malfunction requires a professional, the three most likely culprits are the contactor relay switch, the condenser fan motor, or loose wiring. If your unit is making a buzzing, we highly suggest you call a HVAC professional immediately.

Although your air conditioner makes a variety of noises during operation, there are certain sounds that should not be considered normal. If you hear a rattling, squealing, or buzzing noise coming from your unit, turn the system off and contact a professional to inspect and diagnose the malfunction before it becomes a major issue.

Leave a Reply

Your email address will not be published. Required fields are marked *

Verification: * Time limit is exhausted. Please reload the CAPTCHA.