A heater is a must-have to keep your home warm and cozy during the cold winter months. But what happens if there’s a burning smell when you use the heater? Depending on the cause, an unusual odor could be no big deal, or it could be cause for concern. Here’s what to look for when you notice a burning smell when you turn on the heat.

Does odor mean there’s a problem with my heater?


Noticing a strange scent when you turn on the furnace can be troubling. However, it doesn’t necessarily mean there’s something wrong with your heater. Some smells are more of a nuisance than a risk, while others might mean there’s a serious issue, so it’s important to figure out what’s causing the scent. The scent of burnt dust isn’t usually a big deal, while the scent of melting plastic could mean electrical issues. If you’re unsure of what’s causing the odor or you want to make sure there’s nothing wrong with your furnace, contact your local HVAC company for maintenance services.

What is that burning dust smell?

Is there a scent of burning dust when you start the furnace? It’s likely that – burning dust. When you only use your heater during part of the year, it spends the rest of the year gathering dust. When you finally use the heater again, the dust burns off and creates a burning smell.

How to stop burning smells

The burning dust smell should go away once the heat has burned up the dust, likely within about 10 minutes or so depending on how much dust has accumulated. To confirm that dust is causing the scent, you can look at your furnace or air filter to see if you can physically observe the buildup of dust. Cleaning the air filter may help. If the scent doesn’t go away or gets worse, turn off the furnace and call an HVAC company like Legacy Heating & Cooling for an inspection service.

Dirty air vents and filters

Wiping down a dirty air vent

A burning smell isn’t the only scent you might notice coming from your heating system. If you turn it on and there’s a musty scent, there could be mold or mildew in your furnace or ductwork. Condensation can form in the air ducts and may remain there if there’s a high humidity level. Condensation plus dust and other debris in your heating system creates the perfect conditions for mold and mildew to grow. Additionally, a clogged air filter that is full of dust, pet hair, and other debris can lead to strange smells when you fire up your furnace.

How to stop musty smells

To get rid of a musty scent, shut off your heating system and clean the air filter or replace it with a new filter. If this doesn’t solve the problem, contact your HVAC company for a cleaning service to remove the mold and mildew.

Electrical wire damage

Do you notice a burning plastic smell when your furnace turns on? This could be caused by an electric issue. As your furnace ages, the blower motor may stop functioning properly. The heater may then draw extra electricity to help keep things running, and that added voltage could cause heat to build up. The heat can melt the plastic insulation on the electrical wires, eventually leading to sparks and electrical shorts and an unpleasant odor. Incorrect installation of your heating system or general wear and tear can also damage the wiring. Damaged wiring can cause the heat exchanger to crack or the blower motor to overheat, both of which are serious issues.

How to stop electrical smells

An electrical burning odor means you may have electrical issues, which could become a serious problem. If you notice this odor, stop using the heater and contact your HVAC company for an inspection service.

Debris trapped in the heater

If you smell a burning odor or some other strange scent when the heater is turned on but can’t determine the cause, something might have gotten stuck your HVAC system when it wasn’t in use. An object might have fallen through an air vent and into the ductwork. Or, you may have a buildup of dust and debris.

How to stop strange smells

If you notice an unusual scent but aren’t sure what’s causing it, see if you can pinpoint which air vent the scent is coming from. Then, switch off the furnace’s heat and look into the air vent to see if you can find a stuck object or something else that could be causing the smell. You might also try reaching into the vent to see if there’s an object you can remove. If you can’t see or reach anything and the scent doesn’t go away, contact your HVAC company for an inspection service.

How to prevent odors when you turn on the heat

There are a lot of potential reasons why you’re smelling a burning smell or another unfamiliar scent when using your heating system. The best way to prevent a burning smell is to have an HVAC professional perform regular maintenance on your heating and cooling system. Maintenance provided by Legacy Heating & Cooling includes services like a full inspection, filter inspection and changes, HVAC cleaning and debris removal, and other helpful services to make sure your HVAC system is ready for use when the weather changes. If you want to try a quick do-it-yourself solution first, try changing the air filter and seeing if the burning odor goes away. If it doesn’t, be sure to contact your HVAC company.

Contact Legacy Heating & Cooling

If you live in the Columbus, Ohio area and smell burning or see smoke when you use your heater, contact Legacy Heating & Cooling. We offer inspection, maintenance, and repair services to make sure your HVAC system is working properly and achieving high indoor air quality.

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