Burning Smell from Heater

If your heater smells like burning, then it may be a sign that your furnace needs maintenance. It could be something as minor as a dirty filter, but it could also be a serious problem like an electrical component failure. Don’t ignore it. Try to find the source of the burning smell to avoid costly repairs.

4 Reasons Your Furnace Smells Like It’s Burning

Here are four reasons why your heater smells like burning, and advice on how to handle it:

1. Furnace Smells Like Burning Plastic Smell or Burning Rubber

What should you do if your heater or furnace smells like burning rubber or burning plastic?

If you notice an odor that smells like burning plastic or burning rubber your furnace could have a more serious problem.

It’s possible that a foreign object like a child’s dropped toy, or an unnoticed spill could be in your HVAC system’s ductwork. Turn off your furnace and remove your registers so you can clean or remove any objects that don’t belong.

Sometimes a burning plastic smell can be the sign of an electrical failure. Malfunctions in the heater can cause the plastic wire casings to fail and meltdown. The melting of casings can also cause a burning rubber smell.

If you did not remove a foreign object that was the cause of a plastic smell, you should stop using your furnace and get an electrician out to inspect it right away.

An electrical burning smell could also be something more serious like an overheated furnace motor or a cracked heat exchanger. Call an experienced technician to check the electrical components in your furnace.

Finally, sometimes plastic pieces in the furnace can become dislodged during regular use. In one case, a humidifier had a nozzle installed above the furnace that was supposed to disinfect the air stream. This plastic broke off and fell onto the heating elements.

This isn’t uncommon, and you should have a technician inspect your system right away at any sign of a burning plastic or rubber smell.

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2. Furnace Smells Like Smoke

What should you do if your furnace smells like smoke?

If you smell a smoky smell coming from your heater, you will want to call an HVAC technician right away.

If you have an oil furnace and smell smoke or oil, it could mean a serious problem with your furnace.

A blocked chimney can also cause a smoky smell, so in any case, you’ll need to call a professional to address the cause of the burning smell.

You’ll want to address a smoke smell immediately.

3. AC Smells Like Burning Dust

What should you do if your heater smells like burning dust?

Dust and dirt collect in your air ducts all the time, even when the furnace isn’t in use. When you turn your furnace on for the first time each year, this collected dust has to burn off.

You don’t need to be concerned if this is the first time you’re turning on the heater for the year. The smell should dissipate in a few hours.

If the smell persists, you can check your air filters. A dirty air filter can cause a dusty burning smell downstream.

It’s also possible that the heating elements are dirty. Sometimes you can reach these to clean them yourself. Some elements like the heating strips are difficult to get to because they’re located behind the rest of the wiring for the HVAC system, so you should get professional help cleaning these.

4. Musty Smell Coming From AC Unit

What should you do if your furnace smells musty or like mold or mildew?

A musty odor could mean that mold is on the furnace filter, the humidifier filter (if you have one), or trapped in your system’s ductwork.

Inspect the filter once a year and replace or clean as needed. You can clean a humidifier filter with a solution of equal parts water and vinegar. Soak the filter in the vinegar solution and gently clean with a damp cloth.

If changing and cleaning the filter doesn’t resolve the musty smell, you may want to consult with a licensed provider of duct cleaning services. You should expect your technician to clean up any growths, show you photographs (or other evidence) of the growth, and to diagnose what is causing the growth and provide a suggestion for remedying it.

It’s important to remember that cleaning up the mold isn’t enough. You need to fix the conditions that allowed it to grow in the first place, or you will just be paying to clean the ducts again later.

Contacting Complete Air Mechanical for Any HVAC Service Needed

Whether your furnace smells like mold, dirt, or burning plastic Complete Air Mechanical is here to help. Schedule an appointment online with us today, and we’ll diagnose the cause of your unpleasant furnace smell.

Call us today at (407) 915-0144 or schedule an appointment online.