If your furnace smells while running, it’s attempting 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 fix them. These include:
- Burning smell from furnace
- Furnace smells like burning plastic
- Gas smell from furnace
- Furnace smells like sewer
- Furnace smells musty
1. Burning Smell from Furnace
Cause: Dusty Furnace
If your furnace smells like burning, it’s probably happening 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 off when you turn on the heat, resulting in the burning dust smell from your furnace.
2. Furnace Smells Like Burning 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 created by melting plastic wire casing, which is a safety issue. If you’re noticing a melted plastic smell, turn off your heating system right away and call us at 662-281-1231 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 gets rid of carbon monoxide that’s naturally created during the combustion process.
If it cracks, carbon monoxide can seep into your home. This colorless gas is fatal in heavy concentrations. So, it’s important to have an HVAC professional do annual 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, such as formaldehyde
- Water around your furnace, as long as the condensate drain isn’t blocked
- Flu-like symptoms
3. Gas Smell from Furnace
It’s normal for your heating system to give off a little bit 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 continuously, shut it down. 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 make sure you don’t have a gas leak. If you don’t, the issue 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 problem, you might have a sewer leak, so you’ll want to contact a company that handles sewer line repair.
5. Furnace Smells Musty
If your furnace smells musty, mold and mildew has probably been growing in it for a while.
Cause: Dirty Ductwork
Your furnace uses air ducts to send warm air across your home. Mold can grow in the ductwork over time, especially if you live in a humid climate. You can get rid of the mold by having an HVAC technician do air duct cleaning.
Trust Us with Your Furnace Repair Needs
Troubleshooting your heating and cooling system by yourself is hard. Your comfort is our top goal at Franklin's Heating & Air Conditioning, Inc, so our professionals are here to help you when you need us. When you need furnace repair in Oxford that you can depend on, call us at 662-281-1231.