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Why Is My Furnace Making Noise?

By November 12, 2019March 11th, 2020No Comments

Is your furnace making noise? A noisy furnace can mean several issues ranging from a quick fix to a serious problem. But how can you tell which issues are a simple solution or seriously scary? Furnaces can be tricky and dangerous, so it’s never a good idea to go digging with your toolbox. Instead, try identifying these sounds, and your descriptions can help any trained professional at Lowery to quickly and safely resolve the issue. 

Loud Boom

A delayed ignition may cause a loud boom, pop, or bang. A delayed ignition can create an excess of fuel build-up in the combustion chamber, creating a loud noise to flow through your home. This is one of the more serious sounds and should be checked out by a technician or pro immediately. 


Low persistent rumbling can indicate an issue with your furnace’s burner. You should turn off your furnace and contact a professional as soon as you notice any constant rumbling. 


If you hear rattling coming from your furnace, there may be a broken component inside or a failing motor. A good rule of thumb is, the louder the rattle, the more serious the issue. Calling a professional technician to inspect the problem will ensure your safety. 


Loud banging sounds when your furnace is one can indicate an array of issues. These problems can range from closed vents, a broken/disconnected component, a clogged filter, or undersized ducts. Contact a certified technician to examine and resolve the issue. 


When your furnace is first turned on, a brief squeal is typical. However, a constant screeching could indicate motor bearings in need of oil, a loose fan belt, or a failing compressor. You should contact a professional if the squealing persists. 


Metal-on-metal sounds like scraping are common issues created by a broken motor mount or a loose or broken blower wheel. With either case, turn off your furnace and enlist in a certified technician to help the situation to prevent any further damage to your furnace. 


If you hear any whistling coming from your furnace, this is most likely caused by duct leaks. You should contact a professional so they can quickly and easily find and repair them. 


When you turn your system on and off, hearing a clicking sound is normal. However, if the clicking continues and repeats, you may have a bad relay. Get in touch with a certified technician to inspect and make necessary repairs or replacements. 


Hearing any thumping or vibrating coming from your furnace can typically be the result of a damaged or unbalanced blower motor or wheel. Be sure to turn your system off until it can be examined by a professional to help avoid further damage.


If you hear humming from a system that has already been experiencing issues, the humming noise may be the result of a bad motor or failing capacitor. In a properly functioning furnace, these humming noises can indicate a loud transformer. 

Is your furnace talking to you? Have a trained professional from Lowery diagnose your furnace’s issues and save you from further costly damage and keep your home safe.