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With Indianapolis winters having an average temperature below 46 degrees, there is no doubt that people rely on their furnaces. Sometimes furnaces produce concerning sounds, but what about concerning smells? Left unattended to, certain furnace smells could cause damage and expensive repairs.

The 5 types of furnace smell that users should address right away are:

Musty or Moldy Smells

When the user starts up the furnace after not using it in summer, they may encounter moldy furnace odors. Oftentimes, if they smell mold, that means it’s present nearby. Users may have mold growing in the ductwork in their homes. It’s also possible that there is mold on the air conditioning coil above the furnace.

Call a trusted furnace technician to perform an inspection. For safety, the mold will need to get cleaned out of wherever it is found.

The Smell of Rotten Eggs

Fuel providers put odor-creating substances in natural gas to help detect gas leaks

If users smell something like rotten eggs or sulfur coming from the furnace, turn off the furnace and call a technician right away. A rotten egg smell usually indicates a gas leak. Fuel providers put odor-creating substances in natural gas to help detect gas leaks. If users end up smelling the odor, it is an indicator of a natural gas issue.

Gas leaks require immediate attention because they could cause explosions or fires. The furnace could also be experiencing a failed heat exchanger. A failed heat exchanger can pump carbon monoxide (CO) gas into their home. Be sure to test for carbon monoxide as high levels of the gas are dangerous.

Smoke Odor

The smell of smoke coming from the furnace is usually the result of a blocked chimney. A blocked chimney forces the smoke to go through the ductwork.

If the smell is strong, or if the smoke detector goes off, shut off the furnace right away. In the case of a sudden, strong smell, leave your house and call a professional immediately.

Metallic Smells

If the electrical elements in the furnace get too hot, they may produce a hot metal smell

If the electrical elements in the furnace get too hot, they may produce a hot metal smell. The same issue can also produce smells like burning oil, plastic, or rubber.

Excessive furnace heat can damage metal and rubber components. Turn off the furnace and call a technician right away. This will reduce the risk of fire and prevent an automatic shutoff.

Dusty Smells

Users may experience a dusty smell after starting the furnace for the first time in a while. Usually, this is a normal smell, and it will go away after the dust in the system blows off.

If for some reason the dusty odor doesn’t go away, there could be an issue. Try changing the air filter. If the odor persists, call a professional for help.

Professional Help for Furnace Smells

If users live in Indianapolis and experience any of these concerning furnace smells, LCS Heating and Cooling can help.

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