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Your Comfort is Our Priority!

Emergency Service



Beware Your AC If It’s Making These Noises

Monday, September 16th, 2019 at 11:00 am

vent-on-wallIt would be great if we had air conditioners that could self-diagnose themselves when something was wrong, and send us a notification about exactly what the problem is and how much it will cost to have a professional fix it.

But alas, this is not the case—at least, not yet. This may be a reality in the future, but in the meantime, we all have to rely on other methods for our air conditioners to send warning signs that something is amiss. Perhaps it’s a drop in cooling power or an unexpected increase in utility bills. It may even be that the circuit breakers for the indoor and outdoor units are constantly tripping.

One of the most common signs that something is wrong with an air conditioning system is strange, unfamiliar sounds. What qualifies? Truthfully, anything that’s outside of the normal hum of the fans and the occasional clicking as the system comes on and shuts down. So, what sounds are we talking about? Keep reading to find out!


This is definitely not a noise that’s easy to ignore—the sound of a loud mechanical shrieking. You’re probably dealing with a motor problem, or a motor bearing that’s worn down.

What happens is that these intricate bearings are lubricated so that they don’t create friction, but that lubricant wears down and must be replaced by an experienced HVAC professional. If it wears down too much, the motor can easily overheat, causing a system breakdown.


Grinding is another indication that something can be wrong with the system’s motor. It’s usually caused by a motor that’s accumulated too much debris, or again, lost too much lubrication. This is similar to the above situation that it’s a sign of wear and tear.

However, you likely won’t have to deal with this at all if you invest in professional maintenance once a year from a trained HVAC technician (twice a year, if you have a heat pump system!)


Rattling can be indicative of a “minor” problem, but we don’t expect you to go investigate it on your own. It can be the sign of a cabinet door coming loos, or it can be something more serious, like loose components being knocked around in the blower fan, or a bent fan blade.

It may even be that your air conditioning cabinet is coming loose from the slab, or you have duct damage and that’s where the noise is coming from. It’s not something that you should try to diagnose—particularly if your foundation or ductwork is affected—as only a trained pro knows how to work around the building materials of your home so that no further damaged is cause trying to repair the problem.

Hissing or Bubbling

There’s a fairly common misconception that refrigerant is something that runs out of an air conditioner like gasoline runs out of a car. It should actually last the entire lifespan of your air conditioner, however. If you hear a hissing or bubbling sound, it can mean you have damage to your refrigerant line and it needs to be repaired with the refrigerant being recharged (refilled).

A refrigerant leak can be devastating for your air conditioner, and only a licensed professional can deal with this hazardous substance. If you suspect a refrigerant leak, give us a call today!

For quality St. Augustine, FL air conditioning repair, look no further than Climate Masters—serving St Johns County since 1988 with quality, hometown service.

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