Why Does My Furnace Smell?

Nov 19, 2019 | Blog

Why Does My Furnace Smell?

It’s a common occurrence to notice an unusual smell when you first turn on your furnace for the winter. This is especially true if you have an older-model heating system. The odors are usually harmless, but you do need to be aware of the different types of smells your furnace can produce and what each one could mean, for your safety and the safety of your family and your home. 


If Your Furnace is Producing a Chemical Smell: 

Chemical-type odors coming from your furnace when it is switched on often denote damage to your system’s heat exchanger. The heat exchanger plays a vital role in your system as it is responsible for carrying away the heat and fumes from the combustion chamber and clearing them out of your home. If there is a possibility of damage to the heat exchanger, the situation must be considered a serious one. Deadly carbon monoxide gas could fill your home, or it could catch fire. If you notice this type of odor, shut down your heating system and get everyone out of the house immediately. Go to a safe location and call your local fire department and an HVAC specialist. The levels of carbon monoxide gas in your home will need to be measured, and it will need to be verified that no fire has been sparked. 

Before cold weather sets in, equip your home with working smoke detectors and carbon monoxide detectors. Make sure each one has new batteries and install them throughout your home near bedrooms and on every floor. This is one of the most effective ways to protect your home and your family. 


If Your Furnace is Producing a Burning, Electrical Smell: 

If there is a burning, electrical odor coming from your furnace when it is switched on, this is an indication that some component of your system is becoming overheated. Electrical wires inside your heating unit are located near one another. If they become loose and entangled, they can catch fire. They may also become dislodged and come into contact with heated metal pieces inside your furnace, sparking a fire. At the first sign of this type of odor, shut down your heating system immediately and call an HVAC technician. 



If Smoke or the Smell of Smoke is Coming Through Your Furnace’s Air Ducts: 

If smoke is physically coming out of your air ducts or if you notice the smell of smoke, get everyone out of the house immediately. This is an indication that a fire is present somewhere within your system. Contact the fire department and an HVAC technician immediately from a safe location. 

Smoke can also find its way into your home if your chimney becomes blocked. This situation is not as dangerous as a fire, but it is still a serious one. When smoke and fumes have no way out, they will back up and fill your home. Shut down your heating system and contact an HVAC specialist if this happens. If the odor or the smoke are not very strong and seem to be dissipating on their own, open doors and windows to help get fresh air circulating and clear out the smoke and odor. However, if the smoke and the smell tend to linger or seem to get stronger, turn off your furnace, get everyone out of the house, and call for help immediately. The fire department and an HVAC specialist should be notified right away. 


Other types of odors may be noticeable once your furnace is turned on for the winter season. For the most part, they are not serious and do not indicate any problems. Most will go away quickly on their own. These include:


Dry, Dusty, Burning-Type Odors 

Dust, dirt, and debris can accumulate throughout your heating system during the warm weather months when it isn’t being used. Once it is turned on for the winter, there may be a slight burning odor the first few times your furnace is in use. This is simply the dust and debris heating up and being burned out of your system. Before you turn on your furnace for the first time when the temperatures drop, replace the air filter. This will alleviate many of the odors that can result from your heating system having been dormant for a few months. Make sure to check the air filter regularly and change it as needed or at least once every 90 days during the cold-weather season to protect your HVAC system and keep it in top working order. 


An Odor of Oil Coming from Your Furnace 

An odor reminiscent of the smell of oil means that you need to replace your furnace’s oil filter. Once a clean filter is in place, the smell should go away. If it does not, contact an HVAC technician and schedule an inspection. 


Unpleasant, Musty Odors Coming from Your Furnace

Dust and debris aren’t the only things that can settle into your heating system during the months when it is not in use. Mold can actually form within your system, its spores becoming airborne and being circulated throughout your home. This creates an unhealthy environment for you and every member of your family. You can avoid this by scheduling a professional HVAC inspection and thorough cleaning before cold weather digs it’s claws in for the season. 


At Centerville Heating and Cooling, our fully trained professional HVAC technicians are available to provide you with a complete HVAC inspection and cleaning to ensure that your system is ready to take on the frosty season ahead. Call us today at 937-353-1169 or visit us on the web at https://www.centervilleheatandcooling.com/appointments/ to schedule your appointment and get your home winter-weather ready.