Why Does My Heater Smell Like Something Is Burning?

Your air conditioner worked hard to keep your home comfortable all summer long. During that time, you may have noticed some strange smells coming from the AC vent. Thanks to Aire Serv®, you were able to identify which of these were harmless and which were toxic.

Now that the weather is turning colder, you’re starting your heater again for the first time in months. When you do, don’t be surprised if you’re greeted by a new set of furnace smells.

One of the most common smells is that of something burning. There are different types of burning smells, some of which are harmless, while others could endanger your safety. Learn how to tell the difference so you know when to call a Heating technician.

Burning Dust

This odor is very common when turning on the furnace for the first time in the fall. After months of disuse, dust has settled on the heat exchanger, burners, and other Heating components. When the burners ignite, the dust burns off, and the odor exits your air vents.

The smell of burning dust should dissipate within a few hours and is no cause for concern. If the odor persists, try changing the air filter.

Electrical Burning Odor

Other burning smells that occur when you turn the heat on are more concerning. An electrical burning odor could indicate an overheated blower motor. Under normal operating conditions, the furnace should shut itself off if it begins to overheat. If there’s something wrong with this safety feature, your furnace may continue to operate even as the motor works overtime and becomes dangerously hot. A clogged air filter is one possible reason for this heater smell, so try replacing it with a clean filter.

Mechanical problems or frayed electrical wiring could also cause an electrical burning odor when turning on the furnace for winter. To prevent endangering your family, turn off the heater and call an HVAC technician for help.

Burning Plastic Odor

The smell of smoldering plastic could mean a foreign object has made its way into the furnace. A child’s toy, whole-house humidifier nozzle, or other plastic object is Heating to a very high temperature and giving off fumes, which may or may not be safe to breathe.

Shut off your furnace if you detect a burning plastic heater smell. If you can’t locate the source of the problem in the ductwork or near the furnace, call a furnace technician for help.

Smoky or Oily Smell

You are most likely to encounter this heater smell if you have an oil furnace. It’s not a good sign if you can smell the oil your furnace uses to heat your home.

First, turn off the heater and change the oil filter. If the smell persists, call an HVAC professional to diagnose and fix the problem.

Gunpowder Smell

Similar to a burning odor, a distinctive gunpowder-like aroma could result from a fried circuit board or fan motor. It’s not a good idea to continue running your furnace if it emits this smell. Instead, call a professional to perform an emergency inspection before turning the heater back on.

To summarize, a burning dust smell that lasts no longer than a few hours and doesn’t return later in the season is nothing to worry about. All other types of burning heater smells are potentially dangerous and demand inspection from a qualified Heating technician.

If you’re concerned about why it smells when you turn the heat on, contact Aire Serv® today. If your situation sounds hazardous, we’ll send a technician to your door right away to perform an emergency furnace repair.