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Why does my furnace smell like it’s burning, you ask? It should never, under any circumstances, give off a smell, least of all one that smells of something burning. In the overwhelming majority of cases where a burning smell can be detected coming from your furnace, you should immediately switch off the HVAC system and the furnace and call up your local professional HVAC technician.

Fire is one hazard that one should never leave to chance. Over the past five years, house fires in the US have caused more than 2,600 deaths and generated over $6.9 billion in damage, with faulty heating equipment accounting for roughly 14% of house fires. Besides the significant danger to your person and health, fire has the potential to destroy your entire home in a relatively short period.

Even when it is cold and the temptation to keep the system running until a professional shows up to address the problem is strong, be safe and switch it off.


What Could Cause My Furnace to Smell Like It’s Burning?

As with any electrical system, there is always the potential for something to go wrong, resulting in something taking flame. In an HVAC furnace system, even more so. When your furnace smells like it’s burning, the first thing to do is to check whether the filters need changing. Accumulated dust in a filter overdue for a change may warm up, causing a dusty or slight burnt smell. Immediately change the filter, and your problem should be solved. If not, there may be some dust accumulated in the ducts. Rather than trying to get to it yourself, we advise that you call your local HVAC professional.

Gas leaks are potentially very dangerous. That distinctive sulfuric smell is added to gas specifically to enable users to identify a gas leak. Should the odor be more akin to a rotten egg, there is a gas-related problem somewhere. Immediately switch off the system and call a professional HVAC technician to diagnose and correct the problem.

If you have established that the burning smell emanating from your furnace is not dust or gas, you should contact an HVAC technician to look at your system as a matter of urgency. A burning metallic or other burning smell can indicate several electrical or mechanical issues, all of which can be potentially dangerous to your health and that of your HVAC system.


What To Do When My Furnace Smells Like its Burning

It is not normal for any smell to emanate from your furnace, least of all a burning smell. The smell of something burning is an obvious indicator that something is seriously wrong with your HVAC system or furnace.

  • Immediately turn off the furnace. It would help if you effectively stopped whatever is causing the burning smell. Even once you have secured an appointment with a professional HVAC technician, leave the furnace off until the problem has been identified and repaired.
  • Look for visual signs of smoke or fire to rule out an emergency. If there is a fire or signs of a fire, call 911 immediately.
  • Check filters and replace them where needed. A dusty burning smell may be caused by accumulated dust in filters. It may also be caused by some dust accumulated in the duct. Change the filters, but if the smell does not dissipate, call a professional to deal with the problem rather than risking injury trying to remove dust from surfaces that may be hot.
  • Look for signs of burning or melting. Inspect any readily visible equipment for signs of heat damage or melting.
  • Call your HVAC technician. While some parts of the system may be readily accessible, they may be hot. It is always advisable to have the problem professionally diagnosed and solved, not only for your safety but for the sake of any insurance or guarantee issues that may arise. Most HVAC manufacturers and installers require that a suitably qualified and registered individual carries out repairs and maintenance.


How to Avoid a Furnace From Smelling Like it’s Burning

Regular inspection and maintenance is the most effective way of ensuring your HVAC system and furnace remain in top condition for optimal functioning. Always ensure that all filters are changed as prescribed and that general repair and maintenance inspections are carried out at least once per year or as advised by your HVAC installer or manufacturer.

It is also advisable to report any potential problems with your furnace or HVAC system immediately upon discovery. The sooner you address the problem, the less likely severe damage, and the less it will cost to repair it.



Modern HVAC systems are well designed, with many safety features built into the system. The chances of a fire caused by your HVAC system or furnace is relatively small. Still, it pays to err on the side of caution.