Diagnosing the Most Common Smells From Your Heating System

by Guest Posts

Different smells coming from your HVAC system can be a sign of various problems. Some smells may be harmless, while others could indicate a serious issue. If your furnace is producing an unusual smell, you must check it out to ensure there is no danger to you or your home. Keep reading to learn about the different smells coming from your furnace and what they could mean.

Burning Smell


There are a few potential causes for a burning smell coming from your heating system. One common cause is a build-up of dust and dirt on the coils in the furnace or in the ductwork. This can happen over time if the HVAC system is not properly maintained or you are turning on the furnace for the first time in a while.

If your heater smells like burning plastic, it could be an electrical issue. Burning wires is a result of the insulation on the wires becoming overheated and burning. This can occur when the wires are overloaded or when the temperature of the heater is set too high. It is important to check the wiring of the heater and make sure it is not overloaded or that the temperature is not set too high.

Additionally, if you recently refilled your tank with heating oil, any oil that might have spilled could lead to a burning smell for a few days. In general, a burning oil smell resulting from this situation typically isn’t a cause for concern. However, a burning oil smell that lasts longer than a few days should be investigated by an HVAC technician.

Finally, a burning smell might also be present if there is something caught in the system, such as a piece of insulation or debris, and it is burning. If you notice the smell when the system is first turned on, it may be due to dust burning off of the heating elements. Whatever the cause, it is important to have a professional inspect the system to ensure that there is no serious damage and to prevent the problem from getting worse.

Chemical Smell


There are a few possible causes of a chemical smell from furnace equipment. If you notice a chlorine or metallic smell, it might indicate that wires are burning or melting inside the furnace. This problem is more common with older furnaces due to worn bearings that can cause problems with the motor. This can cause the heater to draw more electricity and can melt and burn wires inside the heating system.

If you notice more of a formaldehyde smell coming from your furnace, it could be a sign that you have a cracked heat exchanger. This is a dangerous issue that could result in the release of harmful carbon monoxide into your home. If you notice a chemical smell coming from your furnace system, you should have it checked by a professional to determine the cause and to make sure it is safe to continue using.

Musty Smell

Another common smell is a musty odor. This musty smell could be the result of the growth of mold and mildew due to excessive moisture or humidity. A faulty furnace filter or condensate drain line often causes this. It is important to check the filter and drain line for any blockages or obstructions and replace the filter if necessary. If the drain line is blocked, it may need to be professionally cleaned or replaced. Another possibility is that the system is not properly ventilated. This can also cause a build-up of moisture.

Finally, if the air filter is dirty or clogged, it can cause the system to circulate dust and other particles, which can also lead to a musty smell. If you notice a musty smell coming from your HVAC system, it’s important to investigate the cause and take steps to remedy the problem. Otherwise, the problem can worsen and lead to health problems for you and your family.

While some foul smells coming from your furnace could be benign, if unpleasant smells are concerning or last longer than a day or two, it is important to have them checked out by a professional. Only a certified HVAC technician will be able to determine if you have a serious issue that needs to be addressed.

related articles

Leave a Comment

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out or learn more if you'd like. Accept Read More

Skip to content

Adblock Detected

Please support us by disabling your AdBlocker extension from your browsers for our website.