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Why Is My HVAC System Screeching?


Strange sounds are rarely good. The scratching at the door when you’re home alone. The bark in your child’s cough. The clanking of your vehicle’s engine. So if you hear screeching coming from your HVAC system every time the AC kicks on, there is most likely a problem. Abnormal sounds and smells coming from your HVAC system often indicate issues that you should resolve before they devolve into expensive repairs. Here’s a guide to strange HVAC sounds and smells you may notice in your Marietta, Georgia, home.


Let’s cover that annoying screeching noise first. The blower motor in your HVAC system uses belts to keep it turning. When those belts wear excessively, they start to screech and squeal, which means they’re not far from breaking. You’ll want to replace those belts before they break, or else the blower motor will stop turning altogether.

Thumping, Rattling, Banging

Describe the sounds how you want, but don’t take any loud, rhythmic sound for nothing. These sounds also often have something to do with the blower motor and often indicate a loose piece. If you don’t repair this issue quickly, pieces can break off and lead to worse damage throughout the system. If the bangs are sudden and loud enough that they make you jump, turn off your system and wait for your local HVAC technician.


Unusual smells coming from your HVAC system can be just as troublesome as out-of-the-ordinary sounds. An electrical odor often means your system is overheating and should be turned off until a technician can diagnose the problem. An odor that reminds you of rotten eggs could be a natural gas leak. If you catch a whiff of this, open your windows, get out of the house, and call your local gas company.

Use these symptoms to catch HVAC issues early, and you’ll avoid the expensive costs of repairs. If you think your HVAC system is in need of repair, call E. Smith today at 678-369-8866.

Image provided by Shutterstock

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