AC Sounds to Be Aware Of

AC Unit
Did your air conditioner recently start making a funny noise? Residential and commercial air conditioners often suffer similar problems that result in the same noises. Whether you’re a concerned homeowner or a business owner mystified by strange AC sounds, follow this guide to diagnose and repair the noises.

  • Clicking and ticking at startup: If you hear this sound, it’s likely that loose hardware has gotten inside the compressor. Take a look and see if you can safely remove any loose springs or bolts you find.
  • Squealing at startup: Some commercial and residential AC compressors squeal when they turn on. You know this air conditioner sound is nothing to be worried about if it’s brief and doesn’t last beyond startup. However, if the unit never used to squeal but has recently developed the habit, it may need a repair.
  • Trumpeting at shutdown: The compressor motor may make this AC sound at shutdown if internal refrigerant valves are leaking. As long as you don’t also hear a hissing sound, trumpeting at shutdown is not a concern.
  • Hissing: This sound indicates a catastrophic refrigerant leak that needs professional attention right away. The sound won’t continue very long because it indicates that the refrigerant is dumping into the atmosphere (something the EPA prohibits). You need a refrigerant line replacement and recharge from a professional to get your AC working again.
  • Bubbling: This noise stems from a slow refrigerant leak that introduces gas bubbles into the refrigerant line. Call a heating and air conditioning specialist to perform leak detection and repair as soon as possible if you hear this sound.
  • Animal sounds from the ductwork: It’s possible for animals to sneak inside and then get stuck in the ductwork. Birds clang and flutter around, rodents scratch and gnaw, and insects buzz. After removing the animals with professional assistance, it’s important to discover entry points from outside your home or building and block them so the problem doesn’t recur.
  • Rumbling or whining: This is a warning sign that the fan motor may have a broken internal part. A repair or replacement is required to stop this AC sound.
  • Banging or clanking: Sometimes, this noise indicates that the internal mounts, connecting rod, piston pin or other internal part is loose. Since the compressor on most modern residential and commercial air conditioners is a sealed unit, your only option is to replace it.
  • Buzzing from the outside unit: When the outdoor fan motor buzzes, the wiring or arcing connections may be loose. Carefully check these connections for signs of burning. If you see signs of burning, you could have a serious electrical problem that requires prompt attention.
  • Rattling or clanking: If your residential or commercial AC compressor makes these noises, it’s likely the motor mounts have failed. Despite a normal appearance from the exterior, the motor is thrashing around on the inside. Replacing the compressor is your only repair option.
  • Screaming: A high pressure sensor should prevent the air conditioner from continuing to operate if the internal pressure gets too high, but if you hear screaming, the sensor may be malfunctioning. Turn off the unit immediately and call a professional for help.

One effective way to reduce the occurrence of these air conditioner sounds is to keep on top of preventative maintenance. A tune-up is the best way to catch problems early before they escalate and start making strange sounds. For help quieting down your noisy residential or commercial air conditioner, or to schedule preventative maintenance, please contact Aire Serv® today.

For Further Reading:

Ideal Temperature Settings to Beat the Heat

Keep You and Your Pocketbook Happy with a New Thermostat

What Is Refrigerant and How Does It Help Your Air Conditioner?

Best Ways to Remember to Change Your Filter