AC Noises and What They Mean

Much like your digestive system after a big meal, your AC unit also likes to talk to you by making strange noises when things aren’t going so well. Clicking, whistling, hissing, rattling, gurgling, popping – any one of these sounds coming from your AC can be a sign that there is an underlying issue that needs to be addressed before it causes damage and costly repairs. When your air conditioner is talking to you, it is asking for help! Read on to discover why your air conditioner is making certain noises and what you can do to stop them.

AC Noises and What They Mean

Hissing or Whistling

If you hear hissing or whistling sounds from your air conditioner,  you probably have a refrigerant leak. Leaks are common when ductwork needs maintenance, or it could indicate that the copper wires that transport refrigerant are damaged.

Other common causes of refrigerant leaks include:

  • Damaged valves
  • Holes in a capillary tube
  • Faulty flare connections
  • A rusted heat pump
  • Leaking coils

If you think your refrigerant is leaking, contact a reputable AC company. Exposure to refrigerant can be dangerous, so it’s important to hire a professional to address the problem.

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Buzzing or Humming

Buzzing or humming from your air conditioner usually means there is an electrical issue in your system. Electrical issues are extremely hazardous as many house fires result from sparks that come from bad or damaged wiring. If you hear buzzing or humming coming from your AC unit, turn it off right away and call for help!


Rattling noises are common when it comes to air conditioners. With all the moving parts involved in heating and cooling your home, screws and bolts sometimes come loose. If you can pinpoint where the rattling is coming from, look if anything needs to be tightened in your inside unit and see if you can easily do so. As for your outside unit, it is also common to hear a rattling sound coming from the system. Rattling noises happen when debris falls into the fan grill, usually after a storm or hurricane! Before attempting to remove anything from the fan grills, make sure the unit is properly shut off to avoid injury.

If you have checked both the indoor and outdoor units and ruled out loose parts and debris, it’s probably time for a new compressor. Rattling is one indicator that your compressor is old and needs replacement soon.

Other common symptoms of a failing compressor include:

  • System is blowing warm air
  • Compressor doesn’t turn on at all
  • Circuit breaker keeps tripping
  • Outside unit shakes when it starts up

Contact Complete Air Mechanical for Air Conditioning Repair

If your air conditioner is trying to tell you there’s something wrong with it, don’t ignore it! Your system may continue to work properly, but whatever’s causing the sound could end up causing more damage if it gets ignored. Contact Complete Air Mechanical for your next service, repair, or installation. We have 24/7 Emergency Service. No additional after hour charges apply.

Call us today at (407) 915-0144 or schedule an appointment online.