If your furnace smells while heating, it’s trying to tell you something’s wrong. We’ve compiled a list of the top six furnace smells so you can know what causes them and how to repair them. These include:

  1. Burning smell from furnace
  2. Furnace smells like burning plastic
  3. Gas smell from furnace
  4. Furnace smells like sewer
  5. Furnace smells musty

1. The Furnace Smells Like It’s Burning

Cause: Dusty Furnace

If your furnace smells like burning, it’s probably occurring when you turn on your furnace for the first time in the fall. Like anything else in your house, your furnace gets dusty over time. This dust burns up when you turn on the heat, resulting in the burning dust smell from your furnace.

2. The Furnace Smells Like Plastic Is Burning

Cause: Electrical Problem

If your furnace smells like burning plastic or burning rubber, it might have an electrical issue. 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 419-465-8722 for furnace repair.

Cause: Overheated Motor or Cracked Furnace Exchanger

An electrical burning smell could also mean your furnace motor is overheated or the heat exchanger is cracked. The heat exchanger safely exhausts carbon monoxide that’s naturally created during the combustion process.

If it cracks, carbon monoxide can leak into your home. This invisible gas is fatal in large doses. So, it’s important to have an HVAC professional do annual furnace maintenance and have functional 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, such as 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 starts up, 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 regular basis.

Cause: Gas Leak

If your furnace smells like gas frequently, shut it down. If you know where your main gas supply valve is, turn that off too. Then call the gas company and us for assistance.

4. The Furnace Smells Like Sewage

If your furnace smells like sewer, or rotten eggs, you’ll want to ensure you aren’t dealing with 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 suspect 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 likely been growing in it for a while.

Cause: Dirty Ductwork

Your furnace uses air ducts to distribute warm air throughout your house. Mold can grow in the ductwork as time goes on, particularly if you live in a humid climate. You can eliminate the mold by having an HVAC technician do air duct cleaning.

You Can Count on Us for Your Furnace Repair Needs

Troubleshooting your heating and cooling system on your own is hard. Your comfort is our top goal at Ohler & Holzhauer Inc., so our pros are here to help you when you need us. When you need furnace repair in Port Clinton that you can depend on, contact us at 419-465-8722.