Duct and Furnace Noises: What They Possibly Mean

Your furnace and ductwork have their own language that can help you to determine whether professional attention is needed. If your Charleston-area home is filled with duct and furnace noises, this handy translation guide can help you figure out what they’re trying to tell you to make troubleshooting furnace problems easier.

Duct Noises

POP! Metal ducts expand as they are filled with air, resulting in all manners of generally faint, popping and ticking sounds. These are perfectly normal and are nothing to worry about.

WHISTLE! A lack of return airflow can cause a whistling sound in the ducts. Reduced airflow may cause a number of problems, from higher energy bills to more wear on the system. Check the air filter first, and replace it if it’s dirty. Make sure all of the return registers are open and unobstructed. If that doesn’t take care of the noise, you may have undersized or poorly designed ductwork.

RATTLE, FLAP! Something may have fallen into the return or supply registers, and you’re hearing them move as air passes through. A duct inspection can quickly determine if any foreign object is causing that sound.

Furnace Noises

POP! The plenum, the big metal box on top of the unit that fills with air, is expanding or contracting. Nothing to worry about there. Normal duct and furnace noise includes a lot of popping.

BOOM! That’s never a sound you want to hear from your furnace. A delayed ignition of gas due to dirty or rusted burners causes the gas to build up. It is better to be safe than sorry where furnaces are concerned. You want to minimize the risk of fires or gas leaks. Call an HVAC professional right away.

SCREECH! SQUEAL! It sounds like your blower motor is faulty, needs a new belt, or the bearings need to be lubricated, and the sooner, the better.

Remember that annual preventive maintenance will help prevent most of the common problems that cause these and other strange noises coming from the ducts and furnace.

For more expert advice about duct and furnace noise, or any other problem with your system, please contact Berkeley Heating & Air Conditioning at 843-277-6030. Our technicians can provide solutions for HVAC problems in any type of HVAC system. Call us today!

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