What’s That Smell? Top Reasons for Furnace Odors

A furnace should make homeowners feel warm, not plug their noses. However, it isn’t uncommon for furnaces to smell unpleasant. Sometimes, the smell is related to a significant issue with the heating system. In other cases, the problem is easy to resolve.

This guide will discuss the possible reasons for a smelly furnace and explain when professional help is needed.

Smell of dust

The smell of dust is quite typical and shouldn’t be a cause for concern. For instance, it occurs when the heating unit runs for the first time in a while— like after the summer season. All of which is perfectly normal. Over time, the furnace collects dust if not used. The dust may even have a burnt smell to it. All being well, this should dissipate after a few hours of use. However, if the odor remains for a few days, it’s best to check the furnace motor.

The smell of burning plastic

Unlike dust, the smell of burning plastic is not typical for furnaces and may indicate serious issues with the heating system. Invariably, this smell means a wiring defect or an electrical fire in the furnace. Sometimes, it arises from the furnace motor overworking and causing sparks. It would be best if you shut down the furnace immediately, and the homeowner should seek urgent help from an HVAC technician.

Smell of smoke

The smell of smoke is relatively common for oil- and gas-based furnaces. It often occurs when oil is spilled during the tank refilling process and evaporates as the furnace operates. The smell should fade away after a few hours. If it doesn’t, we advise you to shut off the furnace and call a technician.

The smell of rotten eggs

That awful smell of rotten eggs is the most alarming of all possible odors coming from a furnace. It’s unmistakable and usually indicates a gas leak. Providers add a chemical to gas called mercaptan. It smells like sulfur, which is similar to rotten eggs. They do this to help people instantly identify leaks, as natural gas on its own doesn’t smell. If you encounter this odor, evacuate everyone from the house, open the windows if possible, and call the fire department.

The smell of dirty laundry

The smell of dirty laundry isn’t as dangerous as that of rotten eggs, but it also indicates a severe problem with the HVAC system. Usually, it arises from a bacterial colony growing inside the furnace. When you turn on your furnace, the bacteria burn and create a smell like dirty laundry. Breathing air tainted this way for extended periods is risky, so it’s essential to clean the unit as soon as possible. However, it would be best if you had this done with professional cleaning equipment.

Fix My Air DFW of Fort Worth specializes in residential and commercial HVAC services including routine maintenance, installation, and repair. All makes/models. Call us at (817) 439-9811.