As with any other appliance, a burning smell coming from the furnace is not a good thing. However, it’s not necessarily a sign of the most dreadful scenario. It’s quite often that the burning smell from the furnace is harmless and normal, and even expected. Details come next.
The burning smell from the furnace can have several causes and it’s not always a signal that a fire is about to start. Here are the most common reasons for the weird smell coming from your heating system:
It’s the first time you use it after a long summer nap
It’s October and you have just started to turn on the furnace for a long summer nap. In the summer, dust has collected on the furnace’s internal components, the heat exchanger, and around the burners as well.
Once the furnace begins to heat up, it will start burning the dust which gives the burning smell. It’s expected and it doesn’t pose a safety hazard. You should expect the smell to go away after several hours as the furnace will burn all the dust away.
Extra tip
You can avoid to some extent the burning smell by turning on the furnace until October on a mild day. Open the windows so that the burning smell escapes from the house and doesn’t alter your comfort inside.
The burning smell doesn’t go away after a few hours
If it’s the first time after a long summer that you use the furnace and the burning smell doesn’t go away after several hours, you might have a problem. The air filter could be clogged or an electrical problem has occurred.
Start with examining the filter. Many times, the blower motor is clogged and works a lot, ending up overheating and generating the burning smell. If the filter is clogged, it will produce dirt and debris that buildup on the furnace, causing the furnace’s burning smell. You can change the filter or call the HVAC technicians for a system cleanup.
If the filter isn’t clogged, you might have an electrical problem on your hands. It’s a severe fire hazard so you must call a certified technician. Typically, the furnace is supposed to shut off on its own if it overheats. If that doesn’t happen, a safety feature is compromised and you will have to service it immediately.
The furnace smells like burning plastic
Several reasons can make your furnace smell like burning plastic. A foreign object might have gotten into the HVAC system (a toy, a plastic fork, anything similar) and went down into the furnace, burning and causing the smell.
Burning plastic smell can also come from an overheating kitchen appliance; broken or worn out components of the furnace may also cause the smell. Smell like burning plastic is a particular smell and requires attention and servicing from a HVAC technician. Burning plastic can produce toxic fumes.
When you sense a burning smell from furnace vent, an overheated component or electrical wire could be the cause. Diagnostic from certified technician is required.
Do you sense burning oil or smoky smell?
An oily or smoky smell coming from an oil furnace means that it needs oil filter change to prevent overheating. If you replace the oil filter and still sense the smell, the chances are that the system is damaged. You will have to call the HVAC technician. Until he comes, you should turn off the furnace right away so that the system doesn’t catch fire.
How to get rid of the burning smell from the furnace?
You can remove the dusty smells by changing the filter on the furnace. Otherwise, you should call the heating technician to stay on the safe side. In the meanwhile, here’s what you should do:
Turn off the furnace
Don’t let the furnace run while you look for the cause of the burning smell. Turn off the furnace and examine it to discover the cause. Call a certified technician just to stay on the safe side.
Look for burn damage
After the furnace cools down, check it out and examine the nearby objects. See if there are signs of burning or melting—they can help you find the source and manage the damage.
If possible, clean the air filter and equipment
You might need specialized equipment to clean the air filter on your furnace. However, you might be able to dust and wipe down the dusty parts.
Call the professionals
If the problem isn’t a dusty air filter, you should contact the professionals to service the furnace. A burning smell can signal problems that are better left to the professionals.
See if there’s smoke or active fire
Always call 9-1-1 the moment if you discover fire or smoke!
