What Is the Cause of the Burning Smell from Turning on the Furnace?

What Is the Cause of the Burning Smell from Turning on the Furnace?

You may be the type of person who turns on the furnace as soon as the home gets a slight chill, or you may be the type of person who waits for that first, complete cold snap. Whatever the case may be, if you smell a weird odor when you switch on your furnace for the first time, do not go into panic mode. More often than not, it is completely normal. Here are a few smells that may come from the furnace, what the odors are, and what—if anything at all—you need to do.

Normal Burn Off of Dust

If the furnace is not actively heating, dirt particles and dust will settle inside of the heating system and on internal components. Once the furnace is turned on, the dust will start to burn off, resulting in a slight burning smell that should dissipate pretty quickly. In the event that the odor lingers for over an hour or so, inspect the air filter and replace it, if necessary. Alternatively, get in touch with a local HVAC company to perform an inspection of the heating system. 

Not-so-normal Smells

Though the initial dusty or burnt odor tends to be pretty common, there are other odors that aren’t as common that you need to be familiar with.

  • Electrical, plastic, or metallic burning smells – If you notice these odors, you should use your nose and locate the source of the smell. If the smell is indeed coming from the furnace, then the problem may be a wiring issue, worn bearing, or an overheated motor, which means that you need to contact a professional. If the odor is coming from a certain vent or register, there may be a foreign object like a plastic toy in the duct. Still, it may be best to contact a professional if you are unable to see anything.
  • Moldy, musty, or locker room odor – This may be a sign that the air filter is extremely dirty or that there is a buildup of mold or bacteria somewhere in the residence. If needed, check and replace the filter. Another problem may be organic growth on the evaporator coil or possibly even in the ducting. In either case, an HVAC professional or ducting cleaning professional will need to come out to the home and perform a thorough cleaning.
  • Rotten eggs or sulfur smell – If you have gas appliances in the household and smell a rotten egg or sulfur odor, you need to exit the residence and contact the local gas company immediately. There is a chance that there is a gas leak, which is extremely dangerous, and it should be left to the professionals.

The best thing that you can do, though, is to schedule routine furnace maintenance during the fall prior to the weather getting hold to reduce the overall chances of a premature issue with your furnace. Get in touch with Indoor Comfort Systems, Inc., as we can inspect and clean your system and offer recommendations for minor or major repairs to ensure that your furnace continues running optimally.

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Contact us today at (256) 885-0430 for a free, in-person estimate on a new system. One of our knowledgeable Comfort Consultants will be happy to assist you.

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