Decoding Those Weird Sounds Your AC is Making

Monday, September 2nd, 2019

woman-covering-her-earsWouldn’t it be nice if we had air conditioners that could self-diagnose when something is wrong and send a text to our phones telling us what’s up? Let’s face it, this is probably a reality in the future, but unfortunately, we’re not quite there yet.

In the meantime, homeowners have to rely on other methods for our cooling systems to send warning signs. Some indicators might include a drop in cooling power, or an unexplained spike in energy bills. Or it may even be that your circuit breakers for the indoor and outdoor units keep tripping.

Another possibility is that you hear strange sounds coming from your air conditioner. And by strange sounds, we mean anything out of the ordinary hum from the fans or whoosh of air through your AC vents. So, what sort of sounds specifically are we talking about? We’ve listed several below. Read on to learn more!


When we say shrieking, we’re describing a rather loud, mechanical sound. This is most commonly an indication of a motor problem, or at least the sign of a motor bearing that has worn down. A worn down motor bearing is not uncommon or “bad,” necessarily. But it is something that needs to be replaced right away.

The reason for this is because it will eventually cause too much friction on the motor, and permanently damage the component. Our professional technicians can quickly and accurately replace the bearings in order to save your moto and prevent further subsequent damage.


This is also a sign of a possible motor problem. It’s usually caused by a motor that has accumulated too much dust, or has lost too much lubrication over the seasons of use. Again, this is a normal part of wear and tear (and something our technicians check on during professional maintenance), however it’s not something you should ignore.

In addition to this grinding noise, you might smell an acrid odor coming from the vents—this is a sign that the motor is already overheating. Please be sure to turn off your air conditioner right away and give our pros a call if this happens.


Rattling can actually end up being a fairly “minor” problem—it can be a sign of nothing more than a loose cabinet door, which is something you can probably fix on your own with a screwdriver.

However, it could be that there are loose components in the system being knocked around in your blower fan, or fan blades that have bents. It may even be that your air conditioner cabinet is coming loose from the slab, or you have duct damage and that’s where the sound is originating.


Whether it’s in gas form or liquid, a hissing or bubbling sound is indicative of refrigerant escaping your cooling system. Air conditioners shouldn’t lose any refrigerant throughout their lifespan—so if yours is, it means you have a leak that must be located and repaired by a trained and licensed professional.

Contact us for professional air conditioning repair in Orland Park, IL. Comfort First Heating and Cooling, where we put your comfort first!

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