Skip navigation

559-255-1644

Serving the greater Fresno area since 1970

Menu

5 Air Conditioner Sounds You Don’t Want to Hear

5 Air Conditioner Sounds You Don't Want to HearAny air conditioner sounds other than the soft whoosh of cool comfort flowing through the vents should draw your attention. They may not turn out to be mechanically significant, but noise that persists should be checked out by a qualified HVAC technician before it becomes more than a simple annoyance.

An air conditioning system incorporates moving parts, high voltage and temperature variations, so the opportunities for noise-making are many. Here are five common air conditioner sounds you may be living with:

  • Squealing or squeaking – These noises often come from moving parts, such as the blower motor bearings, blower pulley or blower fan belt. A service call by a qualified technician can pinpoint the noise. Belts and squeaky pulleys are an easy fix, while defective motor bearings may require blower motor replacement.
  • Continuous rattling when the system is running – If you’re hearing this noise, a part is likely loose. Vibration in the indoor components is limited to the air handler, so suspect the blower motor, motor mounts or pulley assembly. If the rattling turns to loud banging before professional help arrives, turn the system off.
  • Pops and booms – Sheet metal fabrication of ductwork expands and contracts with temperature changes. As the cool ducts warm after the A/C cycles off, expansion of the thin sheet metal may cause faint popping and banging sounds. These should disappear as temperature expansion equalizes.
  • Clicking noises – If you notice repetitive clicking sounds originating from the outside component of the system, you may have a bad relay. This device actuates to switch 240-volt power to start the compressor. It’s a wear-related issue and a familiar repair for a qualified HVAC technician.
  • Assorted outdoor sounds – Noises from the outside unit include rattling that indicates a loose compressor or fan motor, or a loud electrical hum that announces the end of the run capacitor’s expected life span. A “screaming” compressor—you’ll know it if you hear it—usually means replacement is required.

Don’t ignore unexplained air conditioner sounds. In Fresno, contact the A/C pros at Donald P. Dick Air Conditioning.

Our goal is to help educate our customers in the greater Fresno, California area about energy and home comfort issues (specific to HVAC systems). For more information about air conditioners and other HVAC topics, download our free Home Comfort Resource guide.

Credit/Copyright Attribution: “GrandeDuc/Shutterstock”