If you’ve just turned on your furnace and noticed a strange odor, don’t panic — some smells are normal, but others could be a sign that your system needs attention.

The First-Use “Burning Dust” Smell

When you fire up your furnace for the first time each fall, it’s common to notice a slight burning or musty odor. That’s usually just dust that’s settled on your heat exchanger or in your ducts burning off.
It should go away after an hour or two of operation.
If the smell lingers for days or comes back repeatedly, it could mean you have excessive dust buildup or dirty ducts — both can impact indoor air quality and efficiency.

Pro Tip: Schedule a furnace tune-up and duct cleaning to clear out dust before heating season really begins.

Electrical or Metallic Smells

A metallic or electrical burning odor could indicate overheating components, a failing blower motor, or wiring issues.
Shut the system off immediately and call a professional. Continuing to run it could cause serious damage.

This one’s a red flag — don’t ignore it.

Rotten Egg or Sulfur Smell

If you notice a rotten egg or sulfur-like smell, that could mean a natural gas leak.
This is dangerous — leave your home immediately and contact your gas company before calling for HVAC service. Do not turn on lights or electrical switches.

Mold or Musty Odors

A musty or damp smell that doesn’t burn off may mean moisture is trapped in your ducts, furnace, or humidifier.
It could also point to mold growth in your system or drain lines.
Have a technician inspect your furnace and ductwork to find and eliminate the source.

Regular maintenance and humidity control can prevent this problem altogether.

Chemical or Formaldehyde-Like Smell

If you notice a chemical, plastic, or formaldehyde-like smell, it could signal a cracked heat exchanger or other combustion problem.
This may allow carbon monoxide to leak into your home — a serious safety concern.
Turn off the furnace and call One Hour Heating & Air Conditioning right away.

 Stay Safe, Stay Comfortable

Whether your furnace smells dusty, musty, or just plain odd, our licensed technicians can diagnose the issue and make sure your system is safe and running efficiently.

Schedule your furnace inspection today.
📞 Call (816) 354-1077 or Book Online at https://www.onehourheatandair.com/lees-summit/