Why Is There A Burning Smell Coming From My Furnace?

9/30/2023

two women holding their noses because of a bad smell

When the temperatures in Iowa take a dive, most locals turn their furnace on for the first time in months. If your furnace is emitting an unpleasant burning smell, you’re definitely not alone. However, it’s still important to find out why this odor exists and to mitigate it if you can. Here’s 3 reasons why there might be a burning smell coming from your furnace.

1. Accumulated Dust

Even when you aren’t actively using your furnace, it’s constantly collecting dust. This remains true whether you have a heat pump, an electric heater, or a gas furnace. When you turn on your furnace for the very first time during the late fall or early winter, the collected dust and other debris will have to burn up. Dry, dusty, burning smells are usually short-lived. They shouldn’t linger in your house after more than a few hours of continuous heater use. If it doesn’t, be sure to give us a call as there may be a more serious issue.

Although that smell typically doesn’t last long, it’s usually a good reminder that it’s time for your annual Furnace Tune Up & Safety Inspection. Regular furnace maintenance can help minimize or prevent this odor, while also extending the life of your system and ensuring you avoid costly repairs in the middle of winter.

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2. Electric Wiring Issues

It’s often possible to determine the source of unpleasant heater smells by carefully assessing the type of odor you’re experiencing. Odors that are caused by built-up dirt are dry and dusty-smelling. If you detect a faint, slightly sweet odor when your furnace is turned on, this is definitely cause for concern. This is an indication of wiring problems. You may have twisted, frayed, or otherwise damaged wires, or you may have an overheated motor. An electrical burning smell is also a sign of a cracked heat exchanger.

Home heating systems have built-in shut-offs that engage whenever there’s a serious issue that could become a health or safety hazard. However, if your heater is malfunctioning or damaged, it may continue to operate even when it becomes excessively hot or presents other dangers. For odors that are slightly sweet and faintly metallic, it’s best to call a licensed HVAC technician right away. Always turn off your heater and schedule service as soon as electrical problems are suspected.

3. Burnt Rubber Or Melted Plastic

Burnt rubber or the unmistakable smell of melting plastic are also common odors when furnaces are turned on at the start of the winter season. These smells are often an indication that a foreign object has been placed in the heating system or has fallen in there. For instance, if you have small children in your home, there may be a toy in one of the heater grates or vents. These odors can be incredibly pungent and pervasive. More importantly, when plastics melt, they often emit toxic fumes.

If you believe that there’s a foreign object melting in your heating system, turn off your heater and search for the offending object. If you can’t find the problem in an accessible area, you’ll need to call in an HVAC technician. Unlike dust, this isn’t a smell that will simply dissipate after several heating cycles. Most melting plastics will cool and harden in-between every heating cycle. Until they’re located and removed, they’ll be a constant source of frustration. They’ll also lower your indoor air quality.

Scheduling furnace maintenance just before the cold season starts is always the best way to avoid unpleasant odors when this equipment is turned on. HVAC technicians can change your air filter and remove all buildups of dirt, dust, and other debris. They can also spot problems with cracked heat exchangers, malfunctioning motors, and frayed wiring. When furnaces are thoroughly inspected and cleaned, foreign objects such as toys can be identified and taken out as well before they have the chance to overheat and melt.

Give Us A Call

At Service Legends, we’ve been providing reliable home heating services all throughout the greater Des Moines, IA, area for quite some time. We also offer cooling service, air duct cleaning, air purification, and generator installation. If your furnace is emitting a burning smell while in use, we can help.