If your furnace smells while running, it’s trying to tell you something’s up. We’ve compiled a list of the top six furnace smells so you can learn what causes them and how to repair them. These include:
- Burning smell from furnace
- Furnace smells like burning plastic
- Gas smell from furnace
- Furnace smells like sewer
- Furnace smells musty
1. Your Furnace Smells Like Burning Dust
Cause: Dusty Furnace
If your furnace smells like burning, it’s likely happening when you turn on your furnace for the first time in the fall. Like anything else in your home, your furnace gets dusty over time. This dust burns up when you turn on the heat, causing the burning dust smell from your furnace.
2. Furnace Smells Like Burnt Rubber or Plastic
Cause: Electrical Problem
If your furnace smells like burning plastic or burning rubber, it might have an electrical problem. This smell of burning can be caused by melting plastic wire casing, which is a safety issue. If you’re experiencing a melted plastic smell, turn off your heating system right away and call us at 843-485-0967 for furnace repair.
Cause: Overheated Motor or Cracked Furnace Exchanger
An electrical burning smell could also mean your furnace motor is too hot or the heat exchanger is cracked. The heat exchanger safely exhausts carbon monoxide that’s naturally produced during the combustion process.
If it cracks, carbon monoxide can leak into your house. This colorless gas is fatal in large doses. So, it’s important to have an HVAC professional do routine furnace maintenance and have working carbon monoxide detectors.
Other symptoms of a cracked heat exchanger include:
- Soot on or inside the furnace
- Yellow burner flame, instead of blue
- Chemical smell from furnace, like formaldehyde
- Water around your furnace, as long as the condensate drain isn’t plugged
- Flu-like symptoms
3. A Gas Smell Is Coming From the Furnace
It’s normal for your heating system to let off a small amount of gas when it turns on, so you might notice a gas smell from your furnace. But it’s not normal to be smelling natural gas or rotten eggs throughout your home on a daily basis.
Cause: Gas Leak
If your furnace smells like gas frequently, turn it off. If you know where your main gas supply valve is, shut that off too. Then call the gas company and us for help.
4. Furnace Smells Like Sewer
If your furnace smells like sewer, or rotten eggs, you’ll want to ensure you don’t have a gas leak. If you don’t, the problem could be with your sewer lines and not your furnace. This is especially true if it’s been very dry lately.
Cause: Dry Sewer Trap or Sewer Leak
If you think your sewer trap is dry, you can try pouring some water down the floor drain in your basement. If that doesn’t solve the issue, you might have a sewer leak, so you’ll want to contact a company that does sewer line repair.
5. The Furnace Smells Like Mold
If your furnace smells musty, mold and mildew have probably been growing in it for a while.
Cause: Dirty Ductwork
Your furnace works with air ducts to distribute warm air throughout your home. Mold can grow in the ductwork as time goes on, especially if you live in a humid climate. You can eliminate the mold by having an HVAC technician do air duct cleaning.
Trust Us with Your Furnace Repair Needs
Troubleshooting your heating and cooling system on your own is difficult. Your comfort is our number one goal at Olde Towne Heating & Air, so our pros are here to help you when you need us. When you need furnace repair in Mount Pleasant that you can trust, call us at 843-485-0967.