The 5 AC Sounds You Don’t Want to Hear

Did you know that the middle of summer is the most likely time that an air conditioner will break down? This is more likely if you have an aging cooling system, and/or one that hasn’t had maintenance in a while. Remember, a standard central air conditioner needs professional maintenance tune-ups once a year. If you have a year-round heat pump system, then this should be increased to twice a year.

This said, if you’re hearing odd noises, it may be time to call for that tune-up, or better yet, repairs. Sure, no air conditioner is silent! But there are some sounds that you simply shouldn’t hear your air conditioner making, and we’re going to cover those specific sounds below–like clanging, buzzing, booming, excessive rattling, or hissing. Read on!


Keep in mind, we’re not talking about the humming sound you hear as the compressor runs. If we cover a sound you think your air conditioner has been making since installation, unless the sound has changed in volume or severity, you’re probably listening to the day-to-day operations of that system. That said, if you’re hearing a new buzzing noise, what you could very well be hearing is an indication of an electrical problem. This is not only an issue that can lead to AC breakdown, but it could even potentially be dangerous. In the best-case scenario, your electrical panel will automatically trip the circuit breaker for the air conditioner when there’s an electrical problem. But you shouldn’t rely on this–if you hear buzzing, turn off your AC and give us a call.

Clanging or Banging

This is usually an indication that something has come loose inside your air conditioner. The good news is that this isn’t always a severe problem–it could even be a result of natural wear and tear. Maybe a fan belt broke in your aging air conditioner, for example. But, the problem can become severe, the longer you wait to have it addressed. Allowing your AC system to continue running with a loose or failing component reduces efficiency and increases the chance of premature system breakdown.


When your air conditioning system starts up, do you notice a booming noise instead of its usual soft start-up? This is called hard-starting, and it can be a sign of a compressor problem. As the heart of your air conditioner, the compressor has a very important job, so you don’t want to delay having this repaired.

Hissing or Bubbling

Referred to as a hissing noise or a bubbling noise depending on where it is, this sound is indicative of a refrigerant leak. Despite misconceptions about this, refrigerant is not a fuel–it does not run out like gasoline does from a car. So if your air conditioner is losing refrigerant, it means there is a leak. The leak must be located, the refrigerant recharged (refilled), and the source of the leak patched up.

Excessive Rattling

You might always hear some rattling sounds when your air conditioner cycles on and off and as the compressor runs. This can be due to the temperature changes inside the ductwork causing those ducts to fluctuate a bit. That’s fine, but what you shouldn’t hear is new, excessive rattling. It can be the sign of a loose part and can cause a bit of a “domino effect” inside your system, affecting other components.

For quality AC repairs in Brunswick, GA, look no further than HendrixAir, Inc. Contact us today. We are delivering friendly, five-star service, every time!

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