Is Your Furnace Giving Off A Burning Oil Smell? Here's What It Means

When the temperatures drop and you turn your furnace on for the first time of the season, you might notice an unfamiliar smell drifting through the house. Dust that has settled on the heat exchanger, burners, or internal components burn off during that first cycle, creating a brief, harmless odor that usually goes away in a few minutes. There are the common dos and don'ts of prepping your furnace for the chilly winter season, but if you notice a burning oil smell, it could be a warning. This odor can mean a simple maintenance issue or something more serious that would require a professional. Causes of the oily odor can include dust and residue, oil leaks, a dirty or clogged burner, or even a damaged or cracked heat exchanger. 

Understanding the root of that smell can help you respond appropriately. A dusty burner assembly is a common issue and will create a temporary oily scent that quickly clears. The chance of this happening can be reduced when the furnace is cleaned annually, and you follow the recommendations on how often to change your furnace filter, which should be done every three months. You may even want to change your filter more often if you have pets or family members with allergies. For those who have been regularly changing the filter but still notice an oily smell that doesn't go away, you need to dig further into the issue as it is probably not just dust.

If the odor persists, you may have an oil leak in your furnace. This can come from the storage tank, the oil supply line, or somewhere else near the furnace. If you suspect an oil leak, seek assistance quickly because this can be a fire hazard. Leaks can also lead to larger problems like overall damage to the furnace. While you may not realize how much it'll cost to repair your furnace, not addressing leaks can result in extensive and costly repairs including replacement of the unit, which could cost thousands of dollars. If you have an oil leak, contact an expert right away to save money (and headaches) down the road. 

Another issue that would require an immediate call to a service technician is a damaged or cracked heat exchanger. This can cause an oil burning smell throughout the home that can lead to the release of carbon monoxide, which is dangerous and sometimes deadly to people and animals. Signs that you might have a damaged or cracked heat exchanger include rust or corrosion around the exchanger and visible cracks or breaks. You may also notice your carbon monoxide detector going off, or you may smell a metallic odor and see weak or flickering yellow flames on the oil burners instead of a steady blue flame.