Why Does My Furnace Smells So Bad?

Because the furnace is so important to your year-round comfort, you should be familiar with why a furnace smells.

It would be best if you took note of what the different types of furnace smells are to make sure your furnace is working efficiently and accurately year-round.

Reasons A Furnace Smells

Smell Of Rotten Eggs

The smell of sulfur or rotten eggs almost always indicates an issue with the gas supply.

Natural gas is odorless, but suppliers treat the gas with a strong rotten egg smell to make gas leaks more detectable.

If the smell is faint but does not dissipate, turn off the furnace and ventilate your home.

If the smell is strong, call your gas company and follow their instructions.

Dust Burning

The next smell detected by homeowners is one of dust burning.

These are quite normal smells and usually only happen at the change of the seasons between summer and winter.

During the summer, dust builds up on the heat exchanger and the blower. The first time you use it for the cold weather, this dust burns off, and the smell comes out of the ducts.

These types of odors should typically go away after the first few hours of operation.

If not, one can check their furnace filter to make sure it is clean. A technician may also have to be dispatched to your home to do a complete internal cleansing.

Burning Smell Or/And Metallic Smell

When your furnace emits a burning smell or and metallic smell, this is usually a reason for caution.

Burning smells can be a sign of wiring getting too hot, or of your fan motor burning out.

A metallic odor can be a sign of an internal component getting overheating or rubbing up against a moving part.

These types of smells should be checked immediately by your service provider.

If you detect odors like these, you should shut off your furnace right away and call your service provider.

Musty Smell

Mustiness often occurs for similar reasons as burning dust smells. Namely, that dampness has been collected in and on the furnace.

If this smell is faint or goes away after running the heater for a few hours, don’t worry about the mustiness.

If the smell does not dissipate after a few days, there may be mold in your furnace system that’s introducing a damp smell to all your treated air.

Have a professional assess the seriousness of this issue as soon as possible since some types of mold can be toxic when inhaled.

Your furnace is an essential part of your home and provides comfort all year.

It is also a good idea to hire a professional like Guardian Heating & Air Conditioning to inspect and clean your furnace and air conditioner.

If you notice a strange smell coming from your furnace, consider scheduling a professional inspection.

Even harmless odors can linger in your home for the entire season if their cause isn’t addressed.

Get in touch with us at Guardian Heating & Air Conditioning to learn more about what we can do for your home or business.

Give us a call today to schedule your furnace service in Centennial, CO at (303) 952-9047.

“This past year we had Kurt, with Guardian Heating and Air, out to our house to install a mini-split system. We took Kurt‘s recommendation on the sizing of what we needed for our home. WE  COULDN’T BE HAPPIER!!!!! Kurt’s attention to detail and level of professionalism made for a quick and clean installation.  I work as a heavy civil construction superintendent, and having good contractors with a high level of integrity is key to a successful project. I may be in a different trade, but Guardian Heating and Air is somebody I would like to have on my team.”




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