Why Does My Furnace Smell? 4 Odors You Should Never Ignore
All HVAC systems emit odor. Sometimes it’s good, like the scent of breakfast wafting through the house. Sometimes it’s bad, like any of these distinct malfunction-signaling odors:
- Rotten eggs
- Melting plastic, metal or rubber
- Smokiness
- Mustiness
The key to staying safe is to never ignore when your furnace smells — knowing the reasons why it happens makes it easier to ask for help when it does.
When Should I Be Concerned About the Smell Coming from My Furnace?
Don’t ignore any smell coming from your furnace or associated HVAC. If it smells like breakfast, go to the kitchen. If it smells like any of the things listed below, call an HVAC specialist for help right away.
1. Rotten Eggs
This smell is all too familiar to most people, but if you get a whiff of this in your home, it means there’s a gas leak that may be coming from your furnace.
If your house smells like rotten eggs, get everyone out of the house immediately and call your gas company. Make sure to remain somewhere safe until the leak has been repaired by the proper technicians.
Once the leak has been repaired, bring in a trusted HVAC technician for a maintenance check. Even if your furnace needs additional repairs or a replacement to prevent a potential gas leak in the future, this is not a situation to take lightly. It’s crucial to keep your house both comfortable and safe for your family!
2. Something Burning
If you notice an overheating smell or a burning smell from your heater, this could mean that a motor function or other electrical functions in your furnace are getting too hot. These types of odors are typically be described as:
- Burning plastic
- Hot metal
- Melting rubber
- Electrical
Unfortunately, these odors may indicate a component of the furnace is actually burning, and there’s a strong possibility for the problem to escalate and cause a fire.
If your furnace smells like something is burning, turn off your HVAC system and contact an emergency technician immediately. This smell is a sign of immediate potential danger and should be treated that way.
3. Smoke
Keep in mind that the smell of burning and overheating are not the same. Your furnace may emit a burning smell within the first 24 hours after starting it up for the season due to dust that has built up over the summer.
If you notice your furnace smells like smoke for longer than 24 hours, then it’s time to take action. Use the shutoff valve to turn off the furnace, and shut off the gas supply as well. When you call your HVAC repair technician, be sure to tell them the steps you have already taken and where you believe the problem lies.
4. Musty
This is a smell you will notice more in your air conditioning unit due to the buildup of moisture that generates within the unit. It can migrate into the air ducts and cause mold, which will result in a musty, mildew-like smell.
Getting your air duct systems cleaned regularly will save your family from respiratory trouble and your HVAC system (including your furnace) from malfunction.
NOW WHAT?
If your question when you started reading this was, “Why does my furnace smell?,” hopefully now you know the answer and what can be done about it. If the smell has you concerned, we have a 24/7 emergency furnace repair helpline that you can call for immediate support at any time day or night.