Air conditioners are powerful cooling systems that work hard to keep you cool in the hot South Carolina summer, so they’re bound to be somewhat noisy. Some sounds are normal, like the unit turning on, the background noise of the unit blowing cool air, and a few clicks when the unit turns off.

Any loud continuous sound is typically a cause for concern, and a screeching air conditioning unit can indicate an underlying issue with your system. One of the leading causes of a screeching AC unit is a broken compressor system.

Read on to learn more about why your air conditioner is making that horrible screeching noise and how to resolve it.

What Is an AC Compressor & How Does It Work?

Your air conditioner’s compressor begins the chain reaction that cools the refrigerant. During normal operation, warm air passes through the evaporator unit, where heat is extracted from the air.

This heat is then passed to the refrigerant and then to the compressor. The compressor then compresses the refrigerant, condensing it into a fluid and releasing it under pressure.

Infograph explaining what an AC compressor is and how it works

Common Causes of Air Conditioner Screeching Sounds

During the spring, your compressor might make strange noises after activating for the first time for the cooling season. However, if the sound continues or randomly starts after running your air conditioner for an extended period, you need professional air conditioner repair.

Air conditioner screeching and squealing often has one of two causes, and the repair you need depends on the age of your system:

Motor & Blower Belt Failure

If you have an older air conditioner, you can likely hear the screeching sounds from both the outside unit and indoor air vents, causing a real headache for your household.

Older units are belt-driven, and screeching sounds can start when the blower belts have worn out over time or have slipped. A failed blower belt needs to be replaced by a professional.

Fan Motor Bearing Failure

Newer air conditioners all have direct-drive motors, which means they do not have blower belts like older systems. Instead, they use fans to draw air across the condenser coils located within the compressor system.

If it’s been less than a few years since you replaced your cooling unit, chances are you’ll only hear the screeching noise coming from your outdoor unit. When this happens, it’s a sign that the bearings for the fan motor have failed and need replacement.

Other Sounds Your Air Conditioner Might Make That Require Professional Help

Screeching and squealing aren’t the only strange noises your air conditioner might make. Other sounds that indicate the need for air conditioner repair include:

  • Buzzing
  • Rattling
  • Humming
  • Hissing
  • Clicking
  • Bubbling
  • Banging

Schedule Air Conditioner Repair or Annual Maintenance Today!

When you hear strange noises erupting from your air conditioner, don’t attempt a DIY repair to solve the problem.

Preferred Home Services offers the comprehensive AC repair and annual maintenance services that Charleston and Greenville residents need to ensure their systems remain fully operational for the long term.

If your system is making strange sounds, don’t hesitate to contact the cooling experts at Preferred Home Services to schedule an air conditioning repair.

Call (843) 405-3601 to request air conditioning repair or tune-up services in Charleston or Greenville, SC, today!