SAME-DAY SERVICE GUARANTEED - $99 Main Line Drain Clearing Get Offer

SAME-DAY SERVICE GUARANTEED - $99 Main Line Drain Clearing Get Offer

SAME-DAY SERVICE GUARANTEED - $99 Main Line Drain Clearing Get Offer

Why Does My Furnace Smell Like It’s Burning?

Is your furnace emitting a burning smell?

It’s common for furnaces to produce a burning smell when you first turn them on at the start of the heating season. The smell is just dust buildup that will burn off in a few days.

However, if you continue to smell a burning odor, it’s best to contact a professional HVAC technician for a maintenance checkup. Even if the problem turns out not to be dangerous, it could linger and smell up your home for days or longer.

Below, we’ll explore common reasons why your furnace smells like it’s burning:

  • Dust Buildup on Internal Furnace Parts
  • Overheated Furnace Parts
  • Cracked Heat Exchanger
  • Foreign Object Lodged in Furnace
  • Clogged Air Filter
  • Frayed Electrical Wiring

Want Help From Trusted Florida HVAC Professionals?

Contact Red Cap Plumbing & Air! We’ll put your mind at ease with hassle-free furnace repairs and maintenance. Call us or click below to schedule online today.



Dust Buildup on Internal Furnace Parts

For many of our maintenance customers, an odd burning smell travels through their homes when our technician tests their furnaces. That’s the gathered dust from months of inactivity, burning off as a normal part of starting up the furnace. Or you might experience the smell the first time you turn on the heat for an especially chilly day. The smell should dwindle after a few days and only arise after a long period of disuse.

If that’s not the case, or if you smell something that’s not like dust burning off, such as plastic or rubber burning, it’s time to call a technician and explore other potentially dangerous burning causes.

Overheated Furnace Parts


Melting wiring insulation can cause your furnace to smell like it’s burning.

If extended operation or a malfunction causes your furnace to overheat, its parts may reach temperatures it wasn't designed to handle. You could be smelling the finish on metal parts, insulation on wires, or plastic components melting. Or maybe electrical components like the igniter or control electronics are overheating.

Some electrical parts can heat up on their own if there’s a problem, such as a short circuit or failed component. Odors of overheated or failed parts can get into the ductwork and appear anywhere in your home. When you smell something overheating, and it’s not coming from a specific room or device, it’s time to have our experts check your furnace for trouble.

Cracked Heat Exchanger

Your furnace’s heat exchanger prevents dangerous gasses within the combustion chamber from escaping into your air duct network. You could be breathing in potentially lethal chemicals like carbon monoxide if it's cracked.

A carbon monoxide detector can provide an alert, or professionals can survey your home to see if it’s accumulating in bedrooms or anywhere else. Other gasses that might sneak through can be detected, often smelling like car exhaust. This is a critical problem that needs fast attention.

Foreign Object Lodged in Furnace

As with your home’s drains, foreign objects can sometimes find their way into your ductwork. If someone has removed a vent cover and not replaced it, all sorts of objects can enter and reach areas with intense heat. Once the heat starts breaking them down, whether it’s plastic, rubber, paper, dried plants, or anything that smells bad when it’s burned, you’ll smell it.

In this case, you’ll need a professional heating system expert to come and locate the object, carefully removing it from your furnace and cleaning up any remaining material, such as melted plastic. At Red Cap, we offer fast and convenient scheduling so you won’t have to turn the heat off for long to avoid the smell.

Clogged Air Filter


Remember to replace your furnace’s air filter.

A clogged air filter puts abnormal wear and tear on your heating system in many ways. The most notable is the fan motor and belt combination, which are working against a lot more resistance than they usually do. Your system is also designed to transfer heat through the duct system. So, if the air is not flowing freely, the heat may build up inside the furnace and produce burning odors.

The air filter should be changed approximately once a month, year-round, as long as heat or AC is operating and drawing air through it. Blocked vents or air intakes significantly affect airflow and cause similar problems to a clogged air filter.

Frayed Electrical Wiring

Wiring can produce odors in several ways, from malfunctions that cause excessive current flowing through and melting the insulation to short circuits that cause similar effects due to damaged insulation. Depending on the location of your furnace, you might even find that small animals have damaged the wiring in their quest for nesting materials. When your wiring is damaged, it can heat up and release odors into your duct system.

Don’t wait to get it fixed if you smell any electrical odors. Contact a professional HVAC straight away!

Call Red Cap, and We’ll Put a Stop to Your Furnace’s Burning Smell!


Contact Red Cap for a 5-star furnace repair trusted by thousands of Florida homeowners.

With our trustworthy maintenance and repair services, the pros at Red Cap will identify and resolve any burning odors coming from your furnace. Call us or schedule a visit online today to see why we have over three thousand 5-star reviews from Florida homeowners!


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