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Wow, What Is that Sound Coming from Your AC?

old-ac-unitYou’re having a cookout in your backyard and suddenly your AC unit begins making a horrible grinding noise. All eyes inevitably turn toward you wanting to know what that’s all about. Or maybe you have guests over for dinner, and horror movie-style squealing and shrieking begins coming out of the AC vents throughout your house. Once again, everyone will look to you as if to ask, “How could you let this happen?” Don’t worry: There are a variety of causes (and cures!) for these noises coming from your AC which we’ll cover below.

Sources of the Sound Coming from Your AC

No matter the source of the sound coming from your AC, the problem won’t go away on its own. Sure, you may breathe a sigh of relief when an intermittent noise disappears for the moment, but this typically indicates a more serious issue. Talk to your local AC experts to determine the cause of the problem as well as the best way to address it.

1. Thumping and Banging

Sounds like this coming from your exterior AC unit can be a clear sign of trouble with the compressor such as a broken connecting rod or crankshaft. You’ll need to cut off the system immediately and call for expert help. If you need to replace the compressor, that’ll likely cost at least $1,500. Then again, if it’s a loose fan blade – which can sound equally bad – you may have a significantly lower repair bill.

2. Buzzing and Rattling

The sources of these noises vary widely: an air filter which needs replacing, dirty cooling coils, or just loose parts which need tightening. No matter what, it’ll be difficult for the average homeowner to determine the exact cause of these sounds or exactly how to deal with them.

3. Hissing and Whistling

Best case scenario, the source of these sounds will be leaking ductwork. While you don’t want to fix these leaks on your own, a professional will have the right supplies to deal with them. Then again, this could be a sign refrigerant is leaking out of your system, and in that case, you need to call for help right away.

4. Screeching and Squealing

These noises make it sound like you’re in the middle of a scary movie as they travel through and are amplified by ductwork. They’re usually caused by belts in the interior unit wearing out or being loose. You might also have a fan out of balance.

5. Clanging and Grinding

These sounds usually indicate a problem with your fans: either their motors are going out or there is a problem with the ball bearings. You’ll need a professional assessment to determine the best course of action.

Maintaining Your AC System

The best way to prevent an unexpected sound coming from your AC is to keep it in tip-top shape. The best means of doing this is through regular inspections and maintenance. You can always trust our trained technicians to have the knowledge and equipment required to keep your AC system running as quietly as when it was installed.

Contact Cooling Unlimited, Inc. for HVAC repairs in Newton, MA, today!  

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