8 Furnace Smells and What They Mean

Strange smells anywhere in your home can be alarming. When your furnace is producing noticeable smells, you should be aware of what they may mean. While some furnace smells are easily addressed and not very concerning, others can signify a much larger problem or a safety hazard. 

Serious fire and safety risks are associated with smells from gas leaks and overheated components. Residents of Springdale, AR, should contact a local HVAC technician any time they notice new or strange smells coming from their furnace. 

1. Rotten Egg Smells

Natural gas is actually naturally odorless. The sulfur or rotten egg smell is added to natural gas in order to easily identify leaks. This smell is supposed to be alarming and should always be addressed immediately. If your home is one of the millions that receive natural gas, you should be aware of this smell when it presents itself. 

Rotten eggs smells could also be the result of a sewage issue elsewhere in your home. Either way, always respond to these odors with urgency. Contact a company that provides reliable emergency furnace services when you notice rotten egg smells. 

2. Burning Dust Smells

Dust accumulates in your HVAC system for the entire warm season in Springdale, AR. When it is time to turn your furnace back on for the winter, you may notice some burning dust odors. This smell usually will not last long. You can avoid this smell as much as possible by regularly dusting vents and areas around your furnace. 

Dusty smells are typically less concerning than other furnace smells, such as rotten egg smells. However, dusty ventilation can be a real problem for allergy sufferers. If the dust is in your HVAC system, furnace, and ducts, it may be time for a professional cleaning. 

3. Metallic Smells

You can expect a modern furnace to last 15 to 20 years. If your furnace is nearing the end of its useful life, odd metallic smells may become more common. Metallic furnace smells are most often a sign of components overheating. The overheating could also be caused by problems elsewhere in the system. 

If you notice metallic smells, you should immediately turn off your furnace. Overheating components will put your furnace at an increased risk of damage and fire hazards. Contact a professional to identify the root cause and perform necessary repairs. Do not ignore these alarming furnace smells. 

4. Pet Smells

Hair gives off a very distinct smell when burning. If you have multiple furry friends or just one that sheds a lot, their hair may be the cause of your bad furnace smells. Additionally, pet dander and waste can make their way into your furnace if the surrounding area is not regularly cleaned. 

Pet smells typically do not serve as any sign of malfunction in your furnace. The smell of any debris in your home can be amplified by your furnace. The solution to these smells is much easier, but if the problem persists, you may need professional cleaning of your heating and cooling system. 

5. Sewage Smells 

Sewage smells and rotten egg smells are often caused by the same gas leaks. You should invest in a quality carbon monoxide and natural gas detector if you are concerned or at risk for gas leaks. 

Some sewage smells could be the result of an open sewer line or a broken wastewater line. The smell may be entering your home through your vents. Depending on your root issue, you may need service from an HVAC or plumbing technician. 

6. Moldy Smells

Moldy smells are most often noticed during changes in the season. If you notice moldy smells coming from vents, you likely have some mold growing in your ductwork or on the air conditioning coil mounted above your furnace. A mold infestation can very negatively impact the quality of indoor air.

Any mold or mildew smells may be coming from a buildup of bacteria in your system. The humidity levels of your home may need to be addressed if this is a persistent problem. 

If you notice moldy furnace smells, contact a qualified HVAC technician as soon as possible. Your ducts should be inspected for mold, and a professional duct cleaning may be needed.

7. Chemical Smells

A plastic smell from a furnace typically indicates that something has malfunctioned and components are overheating. Wiring is often coated in plastic and can give off a variety of chemical smells. 

If the chemical scent is strong and similar to that of formaldehyde, it is possible that there is a crack in the heat exchanger component of your furnace. This issue needs to be addressed promptly. The heat exchanger malfunctioning can increase your risk of a fire hazard. Contact a professional when you detect any chemical furnace smells. 

8. Smoke Smells

If you smell smoke coming from your furnace, you should turn it off immediately. The most likely cause of smoke smells is a ventilation problem. The exhaust from your furnace may be ending up in your ducts and living spaces. Open up a few windows as soon as possible. 

With smoky furnace smells, the intensity of the odor may indicate the severity of your problem. If the smoke is faint, then you should simply schedule a service appointment. If the smell is stronger, you should call a professional immediately. You will likely need to leave your home until the issue has been addressed if the smoke smell is strong. 

Stith Plumbing & HVAC

We want residents of Springdale, AR, to feel comfortable and safe in their homes all year round. When your furnace is putting out strange or alarming smells, you can trust us to address them. If you are experiencing furnace smells that have not been listed above, contact us so we can help identify your problem. 

If you are unhappy with the function or smell of your furnace, Stith Plumbing & HVAC provides quality furnace inspection, maintenance, repair, and replacement services. Contact us today if you have any concerns about the safety of your furnace.