Why is My Furnace So Noisy?

furnaceEvery furnace is bound to make the occasional sound during use, but do you ever get concerned that the noises you’re hearing aren’t normal? In most cases, the noise is no cause for concern and may even be something you can remedy yourself. We’ve organized (as best we can) some common sounds and what they may mean. Of course, if you have real concern about the sounds coming out of your furnace, the best thing to do is call an HVAC professional.


If you hear rattling or vibrations around your furnace or ducts, you likely just need to tighten things up. Rattling ducts may just need to be secured with tighter or additional screws. In many cases, you can solve a vibrating furnace by simply sliding a rubber or cork pad beneath it. If this doesn’t solve your issue, be sure to call an HVAC specialist.


There are several reasons you may hear a whistling. If the whistling started only recently, the issue may be a dirty filter. When the filter becomes too clogged, the areas where air can get through get smaller and smaller often causing a whistling sound. It may be time to replace the filter.

Whistling can also be caused by issues with the ducts. A small hole in the duct could create the sound, and may be resolved with a piece of tape. In other cases, your ducts may be the wrong size and not allowing for the proper air flow. If the whistling stops once you remove the doors of the furnace, your issue likely is the ducting.

Pops & Bangs

If you’re hearing these noises when the furnace kicks on, there may be a weak spot in your metal ducts. When the fan initially starts, the negative pressure causes the duct to pop inward, then back out once the fan shuts off. If you notice any extra flame or shaking when the furnace kicks on, you may have a more serious issue and should call an HVAC contractor ASAP.

If you have any concerns, don’t hesitate to call the Borden Heating & Cooling team at (610) 325-9966.

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