Furnace Smells Bad: Common Furnace Smells Explained

Furnaces are an essential part of modern homes, providing heat during the colder months of the year. While a new furnace generally functions without issue, there may be times when a homeowner notices furnace smells coming from their unit. This can be concerning, as it could indicate a problem with the furnace that needs to be addressed.

An unpleasant and strong odor emanating from your furnace can not only be off-putting, but could be indicative of an underlying issue or health hazard within your home. That’s why as a homeowner, it’s important to understand what furnace smells are normal and which signify that something is wrong with your heating system. Let’s explore some common furnace smells and their explanations so that you know how best to address any problems quickly and safely.

Burning Smell

A common furnace odor issue is one that comes with a burning smell. This is typically caused by an overheated motor or belt, as well as any dust buildup within the system. Such furnace smells warrant immediate investigation and repair to avoid further damage and health risks due to smoke inhalation. The most important thing you can do is call in a professional technician to check out your furnace if you notice this type of smell after turning it on.

Another possible cause for smoky smells could be due to clogged or dirty filters in your system which don’t allow enough clean air through – leading to debris buildup on the heating elements themselves and eventually causing a smoky odor during operation. Filters should typically be replaced at least once every season – but depending upon your specific model you may need more frequent filter changes than that in order to maintain airflow properly into your system (always consult manufacturer instructions).

Finally, electrical issues could also lead to smoking odors coming from your furnace if there are shorts within wiring harnesses or corroded connections that could potentially produce sparks during ignition sequences leading to smoke coming out of vents where it shouldn’t normally occur. Again it’s best practice here that any sort of suspected electrical fault with any HVAC unit should affirmatively be assessed by qualified professionals only!

Overheated Motor or Cracked Furnace Exchanger

When it comes to an overheating motor, the likely culprit is something called “overruns.” This can happen when parts in the system become too worn to pull heat out of the exhaust properly and cause build up heat. Over time, this can lead to smoke and odors coming from your furnace as well as potentially dangerous fumes if left unchecked. It’s important to have any furnace with frequent overruns checked by a professional as soon as possible for both safety and peace-of-mind reasons.

Rotten Eggs or Sulfur Smell

One of the most common furnace smells are rotten eggs and sulfur smell. This smell usually indicates an issue with natural gas, and should be addressed immediately for safety reasons. The source of this smell is often due to a leak in your gas lines, which can build up inside your home and present a serious fire and health hazard.

To identify if you have a gas supply leak, inspect all pipes near the furnace for signs of corrosion or dampness, as it could be indicating that there is an issue with the pipes or valves that lead to the furnace from your home’s main line. If you do find evidence of a gas leak, evacuate the area immediately and contact your local utility company or qualified heating and cooling system company right away to repair any leaks before turning on your furnace again.

Other common causes of sulfur smells include clogged burners within the unit itself as well as dirt buildup in air filters that need to be changed frequently as part of regular maintenance. Lastly, sometimes air conditioner condensate pans may contain residual water which creates bacteria growth due to its high heat levels creating similar odors throughout your house.

Burning Plastic, Rubber, or Metallic Smell

Burning plastic, rubber, or metallic smells coming from your furnace could be caused by several different factors.

First of all, it could be related to the electrics. Due to a loose connection or wiring issue inside the unit, it may not be supplying sufficient current to heat up and then returning back through the wires—which could cause a burning smell. If this is the case, you should contact an HVAC professional immediately as faulty wiring or damaged protective coating can present a fire hazard.

Another common cause of these odors is dust on burners that has been ignited and burned off due to too little airflow in your system. This type of situation will cause smoke throughout your home so make sure you check for any visible smoke before investigating any further!

In addition, if oil is used as part of your heating system, it’s possible for leaking oil residue to get onto hot parts like burners that haven’t been cleaned recently enough—causing an acrid smell when ignited from the heat generated during operation. In such cases it’s recommended that you contact a service provider who can check for deficiencies and clean out dirty components accordingly if necessary before restarting operations again safely.

Finally, another culprit might be rodents like mice or squirrels finding their way into your ducts and dying there; causing unpleasant smells which would require special attention when dealing with removal after identifying where they are located in order to prevent anything else from entering just in case!

Gas Leak

Gas leaks and carbon monoxide leaks can be caused by an outdated furnace, loose fittings, or cracked heat exchanger. It is important to inspect your furnace regularly for signs of potential gas leaks. Furnaces that are powered by natural gas can pose a safety risk if they are leaking gas, as natural gas is highly flammable.

If you suspect that your furnace may be emitting a gas odor or has carbon monoxide leaks, you should immediately turn off the unit and contact a professional HVAC technician immediately to inspect the system. Make sure that no candles or open flames are present when you leave your house immediately and wait until help arrives before re-entering your home.

Common Repairs for Furnace Smell Problems

The most common furnace repairs for furnace smell problems can vary depending on the specific cause of the odor. Here are some potential repairs that may be necessary during the heating season:

Air filter replacement

If the smell is caused by a buildup of dust and debris in the air filter, replacing the filter is a simple and effective solution.

Burner cleaning

If the smell is caused by dirty burners or rotten eggs, a professional furnace repair technician can clean them to restore proper combustion and eliminate the odor during the heating process.

Gas and Carbon monoxide leak repair

If the smell is caused by a gas leak, a professional furnace will need to locate and repair the leak to prevent a potential safety hazard.

Condensate line cleaning

If the smell is caused by mold or mildew growth due to a clogged or improperly draining condensate line, the line will need to be cleared and cleaned.

Ductwork cleaning

If the smell is caused by the presence of a dead animal in the ductwork, a professional HVAC technician will need to remove the animal and sanitize the system to eliminate the odor.

In general, it’s best to have a professional HVAC technician diagnose and repair furnace smell problems to ensure that the issue is properly addressed and to prevent any potential safety hazards.

Call Us for Affordable Furnace Repair

Now that you know the reasons why your furnace smells strange, it is important that you address the issue quickly to prevent further damage and costly repairs. If your furnace is emitting foul odors and you’re not sure what may be causing them, don’t hesitate to call a trained technician.

Our team of professionals at Good Guys are trained to diagnose and quickly resolve a malfunctioning furnace and strange furnace smells. Whether you need replacement parts or maintenance, we offer affordable repairs for any budget size. Keep yourself comfortable this winter with our reliable services and competitive rates. Call us today for friendly customer service and we’ll get your furnace working properly in no time!

Best Service, Best Prices. Guaranteed!

5 Star Heating and Cooling

530-391-9339