Have you ever turned on your heater and suddenly smelled something burning? It’s very common to notice a musty, dusty burning smell when the heater starts for the first time in a few months. While this burning smell when the heat comes on is not necessarily a fire hazard, it’s unpleasant and can be irritating to people with asthma or allergies.
Where Does the Burning Smell Come From?
The burning smell is usually from dirt and dust that accumulates in air vents, registers, and the furnace itself. Over the spring and summer, parts of your HVAC system gather dust and dirt from disuse. This dirt and dust burns off when you turn the heating system back on.
If you start to smell a musty odor, it can be sign that mold has grown in air ducts. Make sure you call a professional for HVAC service if you suspect mold in your air ducts. An electrical burning smell, or the smell of burning oil can both be signs of serious issues with your HVAC system. Make sure you call an HVAC specialist immediately.
Make sure to check any floor registers to make sure that no plastic items are sitting on the vents, particularly if you notice the smell of burning plastic. It is common for children’s plastic toys or other small plastic items to melt if they sit on hot air registers too long. If they get too hot, they can also cause minor house fires.
When Will the Burning Odor Go Away?
The burning furnace smell usually goes away within a couple of hours, once the dust has burned off of the heating unit. However, it can linger for a couple days depending on the amount of dust. If the “heater smell” gets too bad, open the windows and let the odor dissipate. Keep the heater running through this to get the smell out as quickly as possible.
If the odors linger for a long time after opening the windows, check your air filters and schedule an air duct cleaning if necessary.
Furnace Safety Tips
- Never store combustible materials near your home’s furnace.
- Keep the area around the heating and air condition unit clear. This means no bikes leaning against it or cardboard boxes stacked up.
- Change your air filter regularly
- Test your smoke and carbon monoxide alarms before you turn the heater on in the fall
- If your home’s smoke detector or carbon monoxide alarm goes off after turning on the heater, get out immediately and call the fire department for help.
- Likewise, call your utility provider if you smell natural gas.
How Can You Avoid that Burning Smell from the Furnace?
Avoid the nasty “new furnace smell” by having your air ducts and furnace filter cleaned before turning the furnace on for the first time. This will improve your home’s indoor air quality and protect you against that burning smell from the furnace vent. Also, inspecting your air filters and changing them monthly can help with both air quality and avoiding excess dust in the ducts.
Autumn is when you want to smell pumpkin spice, apple cider, and crackling fires, not the smell of burning dust. If you’re smelling burning when the heater starts, don’t be too concerned. It’s a common issue, and rarely causes serious problems.