“What Was That?” Furnace Noises & What They Mean

The Weiss-Johnson Blog

Problems with your furnace tend to start out small and progress to full-blown, serious breakdowns if they are not taken care of. It’s one of the many reasons proper furnace maintenance by a professional is necessary to keep your system running well all season. How can you catch these smaller problems? By keeping an ear out for out-of-the ordinary furnace noises and understanding what they mean, so you can call a pro and have a repair scheduled –fast!

Booming or Thudding

This typically indicates a problem with dirty burner or even a build-up gas due to delayed ignition. Carbon molecules can build up on the burner and obstruct the jets which makes them fire up later than they should have. A professional will be able to properly clean the burner that is delayed in firing, so your furnace goes back to normal and the booming stops.

Rumbling VS Rattling

The difference is important: a rattling furnace tends to mean something has come loose, like a bolt or part of a panel and simply needs to be secured.

A rumbling, on the other hand, indicates a serious build-up of dirt and grime within the unit and is forcing your furnace to undergo serious strain. A rumbling can also indicate your blower may be out of balance. If you’re hearing rumbling coming from your furnace, the best step to take is to turn your furnace off completely and contact a professional immediately so they can fix the problem.

Grinding or Screeching

A loud grounding or screeching type of sound indicates a problem with your furnace’s motor or a part of the motor, like the bearing or belt.

Intermittent Running

If you hear your furnace turning itself on and off over and over, it means that it is short cycling. This is the result of your furnace overheating and forcing the limit switch in your system to turn on and turn off as a built in safety measure. This will continue to occur until the furnace breaks down if it isn’t repaired right away.

The noises we’ve mentioned today are some of the most common that homeowners tell us they’re hearing. Our expert staff at Weiss-Johnson are fully-trained and capable of repairing your furnace completely so that all disturbing noises stop and your furnace runs at its best!


The Weiss-Johnson Blog Team

We are the Weiss-Johnson Blog Team! All blog posts are written by a collective of WJ employees. Each one of our articles is designed to inform our customers of all the happenings in the world of home comfort! Thanks for reading!

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