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Furnace Odors: Sewage, Musty Smell, Chemical Odor

In part one of this two-part blog series, we went over some common odors you may smell from your furnace, and what they might be telling you. While certain odors in specific situations might not be much of an issue, there are a few others where smells could be signaling a significant issue of some kind within either the furnace itself or some other part of your HVAC system.

At FLAME Heating, Cooling, Plumbing & Electrical, we’re proud to offer a variety of HVAC repair services throughout Michigan, including assistance with any odor concerns taking place within the furnace or other parts of your system. What are some other odors you might smell from this area, and do they signal an issue? Here’s a primer.

Sewage or Rotten Eggs

If you notice a rotten egg or sewage smell from your furnace, this could relate to natural gas, and it’s usually a sign of a gas leak. Without emergency assistance, such leaks can lead to carbon monoxide-related issues and even explosions!

A sour smell may also be related to the combustion fan within your furnace, especially if this issue is persistent. This part needs proper lubrication in order for it to function properly and remove exhaust. If you smell this odor for more than a passing moment or two, you should immediately contact our HVAC professionals for assistance. In some cases, we may even advise you to leave the home until we arrive to remedy the issue.

Musty Smell

As many homeowners are already aware, must is an odor that often indicates the presence of mold or mildew within a given area. If you smell this musty odor from your furnace, either as a sudden burst or a constant presence, it could be an indication that mold spores have released into the air and are now being circulated throughout your home via the heating system. Contact our staff, who will help you confirm and fix this issue.

Chemical Odor

Does your furnace smell like formaldehyde or other chemicals? Especially if this is happening while you also hear a rattling noise, this likely means you have a cracked heat exchanger. All it takes is one small crack to turn into a much larger problem, which becomes evident in the form of this noxious chemical smell.

If you notice any signs of cracks or other serious damage with your furnace’s heat exchanger, call the experts at FLAME Heating, Cooling, Plumbing & Electrical immediately. A cracked heat exchanger risks leaking harmful carbon monoxide, and we can provide any required HVAC repair services as promptly as possible.

For more on what certain smells coming from your furnace area might be telling you, or to learn about any of our HVAC repair or installation services, speak with the pros at FLAME Heating, Cooling, Plumbing & Electrical today.

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