Now that the weather has started cooling down, there is a good chance you’ve probably flipped on your furnace after sitting dormant since the middle of Spring. If you’ve noticed an unpleasant smell coming from your furnace, possibly like something is burning, there are a variety of things that could be happening. Sometimes it’s minor, sometimes it’s a big deal. Either way, it’s always best to call a certified technician from Wyckoff Heating & Cooling to come look at your HVAC unit.

Harmful Odors Your Furnace Could Be Omitting

There are generally a handful of different odors or smells that can leak from a furnace when something isn’t going right. Usually, but not always, there is a correlation with a smell and the issue at hand.

Electrical burning smell

This odor could probably best be defined as ‘metallic’, and it usually correlates with your furnace running too hot. If you smell something like this, this means that the metal casing of your component is running hot and wires are most likely singing within the unit. To avoid your system overheating, forcing an automatic shut off, and potentially causing a house fire, turn off your furnace unit and call a technician immediately.

Rotten egg smell

The putrid smell of rotten eggs of sulfur is something that is intentionally done to warn homeowners of a gas leak in their home. Since natural gas is odorless, gas supply companies scent their supply to give a cue to residents and businesses in the event that their furnace is leaking gas. If the smell is not that strong, turn off your furnace and open the windows in your home or apartment. If the smell is overpowering, open your windows, evacuate your home, and call your local gas company asap. They will be able to guide you through the next steps of what to do.


When you smell smoke, you can be almost 100% sure that heat has built up somewhere in your home and something is starting to catch on fire. This could result from dirty ducts throughout your home where heat can’t escape. This also could happen from your furnace overheating and starting on fire. In this scenario, assess your surroundings and if you are in danger. If a fire has started, evacuate your home as soon as possible. If there is no fire yet, turn off your HVAC unit and call a technician as soon as possible.

Non-Harmful Odors Coming From Your Furnace

Burning dust

Considering your furnace has been sitting dormant for months, there should be no surprise if you smell dust burning for the first 1-2 uses. Dust will generally accumulate both within the ducts and the furnace itself. However, if the smell is persistent after a number of uses, call a Wyckoff technician to come look at your furnace unit.

Oil smell

This is usually correlated with a clogged furnace filter. If you notice a smell of oil, change out your furnace filter and this will most likely resolve this issue. If it continues after, call a technician for service.

Des Moines & Central Iowa Furnace Service Experts

Wyckoff Heating & Cooling has been serving Iowa businesses and residents since we opened our doors back in 1950. We are a family-owned business that focuses on keeping Iowans comfortable, no matter what time of the year. If you haven’t already done so, sign up for our Peace of Mind Planned Service to get a bi-annual service for your furnace and air conditioner unit. We are available 24/7 for any emergency services you need, we look forward to hearing from you!