360-499-6604 If you notice a weird smell coming from your furnace, it’s important to approach the situation with caution. Although the source of the smell might be harmless, it could also pose health risks or point to a more serious issue. In fact, did you know that heating systems were the second leading cause of residential fires in 2022?
When uncertain about what a smell means, it’s best to open windows for proper ventilation and leave your residence. A gas or carbon monoxide leak are two worst case scenarios that could endanger your life.
To help you stay safe and informed, our team has compiled a list of typical furnace odors and what they indicate. These include:
- Gas or rotten egg smell
- Dust
- A burning smell (especially burnt plastic)
- Damp or musty odor
- Formaldehyde
- Exhaust smell
Continue reading to learn more about what these warning signs mean and how to handle them.
Strange Smells From Your Furnace To Pay Attention To
Rotten Egg Smell
A furnace that smells like rotten eggs often points to a natural gas leak. This distinct smell isn’t naturally occurring— utility companies add a chemical called mercaptan to natural gas. Mercaptan is harmless but has a sulfur smell, unlike natural gas, which is odorless and colorless. This safety measure helps homeowners quickly identify hazardous gas leaks.
If you notice your gas furnace has a rotten egg smell, follow these steps:
- Don’t flip any electrical switches, unplug or plug anything in, or use your phone while still inside.
- Open all windows and doors to ventilate the space.
- Evacuate everyone from your home immediately.
- Once safely outside, call 911 and your local gas company.
- Don’t return to your home until professionals have declared it safe.
Dust
If your furnace smells like burning dust, it doesn’t always point to a problem. This usually happens when dust and dirt build up in your system, especially after sitting unused all summer. The most common cause is a dirty or clogged air filter.
Change your filter and soon, the dust smell will dissipate after your furnace has run for a little while. However, if the smell doesn’t go away after 30 minutes, contact our HVAC repair technicians.
Burnt Plastic
A furnace that smells like burning plastic is a serious warning sign that requires immediate attention. You might be smelling:
- Electrical components burning
- Plastic components in your furnace system melting
- Burning rubber
These odors often indicate your furnace or the blower motor is overheating, which can melt various components and wiring. An acrid metallic odor could also suggest damaged wiring.
This situation requires a professional inspection right away to prevent potential fire hazards and costly damage. Call on G&G Heating and Air Conditioning for emergency furnace service.
Musty Smell
If your furnace smells musty or a damp odor permeates your home when your furnace runs, this can point to two main issues:
First, dirty air ducts could be the culprit. Over time, your ductwork can collect dust, debris, and moisture, which creates perfect conditions for mold and mildew growth. When your furnace runs, it circulates these odors throughout your home.
Second, water in your furnace might be the problem. Common causes include:
- Loose drain pan connections
- Clogged condensate lines
- Poor drainage
These moisture issues can seriously impact your indoor air quality and potentially lead to breathing issues. If you’re dealing with musty furnace odors from your vents, contact G&G Heating and Air Conditioning. We provide professional duct cleaning and furnace maintenance to eliminate these problems at their source.
Formaldehyde
If you detect a sharp, chemical smell similar to formaldehyde coming from your furnace, take immediate action. This often indicates a cracked heat exchanger, which is an extremely serious situation.
A cracked heat exchanger can leak carbon monoxide (CO), an odorless, colorless gas that can be lethal. While you can’t smell carbon monoxide itself, the formaldehyde-like odor is a crucial warning sign.
Additionally, if there is no distinct odor in your home but the carbon monoxide alarm is going off, get out immediately.
You should treat either of these situations as if you noticed a gas odor from the furnace. Call 911 from outside and contact your local gas company. Do not reenter until emergency services clear your home.
Exhaust
If your furnace has an exhaust smell, it typically signals a venting problem. Your furnace’s ventilation system plays a big role in safely removing combustion gases from your home.
When vents are obstructed, deadly carbon monoxide and other harmful gases can backdraft into your living spaces. Don’t wait to address car exhaust smells indoors. Contact G&G Heating and Air Conditioning for fast HVAC service in Olympia, WA.
Contact Us for All Your Furnace Needs
Our team at G&G Heating and Air Conditioning can help you address any of the furnace smells on this list, as well as other heating issues. Call us at (360) 499-6604 or contact us online to schedule an appointment.
