Can Furnaces Catch Fire

The return of low temperatures boosts your reliance on home heating equipment every fall. If your furnace isn’t functioning properly, it could become a fire hazard and threaten your family’s safety.

As stated by the National Fire Protection Association (NFPA), heating systems like furnaces are a leading cause of home fires, contributing to approximately 50,000 blazes, 500 civilian deaths and more than $1 billion in direct property damage each year. Space heaters and fireplaces cause the majority of fires concerning heating equipment, but central heaters, such as furnaces, are accountable for about 12% of these blazes. Learn more about the most likely causes of furnace fires and how to prevent them.

Causes of Furnace Fires

Old furnaces are more exposed to safety hazards as they might be configured differently and settle into disrepair through the years. Still, whether your furnace is more than a decade old or brand new, you should be aware of these causes of furnace fires.

An Overheated Motor

A furnace motor can overheat in various ways. Here are the most common risks: 
  • A clogged filter can impede airflow and force the motor to work longer. Eventually, the motor may overheat, raising the risk of fire.
  • Dirt can gather around and cover up the motor, forcing it to retain heat, which can lead to a fire.
  • Exposed or corroded wiring can cause the voltage to increase too much, increasing the risk of an electrical fire.
  • Excessively tight or worn motor bearings can heat up when the furnace starts. Without the proper lubrication, the bearings may eventually light on fire.

Obstructed Furnace Flue

Yard waste, animal nests and other obstructions can obstruct the furnace flue, reducing oxygen. This causes soot buildup and bad ventilation, lowering efficiency and increasing the risk of flame rollout. Flame rollout is when fire gets out of the heat exchanger and burns the parts within your furnace. If this problem remains, your heating equipment could be seriously damaged, and the fire may even spread to areas outside the furnace.

Obstructed Heat Exchanger

The heat exchanger is a restricted combustion chamber where the heat produced by your furnace is moved to the air circulating through your home. A heat exchanger clogged with soot or corrosion has the same effect as a blocked furnace flue—reduced performance and a higher risk of flame rollout.

Cracked Heat Exchanger

Several problems can take place if corrosion breaks the heat exchanger. First, it lowers suction within this chamber, resulting in less airflow and increased flame rollout. Second, it produces fumes, such as carbon monoxide, into your home. Inhaling CO gas can be lethal, so never dismiss your carbon monoxide alarms. CO gas can also flash back to the source of the leak and ignite if a flame is lit.

Inadequate Gas Pressure

Furnaces depend on an accurate combination of natural gas and air to produce safe and efficient combustion. Too little pressure is often because of clogged burner orifices. This problem makes the burner flames more likely to roll out. It also produces unwanted condensation in the heat exchanger, accelerating the rate of corrosion.
On the other hand, high gas pressure can create excessive heat inside the furnace, which can cause the soot inside the heat exchanger to combust. Such fires can readily spread to other areas.

How to Prevent Furnace Fires

Based on the different ways a furnace can combust, here are the steps you can take to avoid furnace fires:

  • Change the air filter consistently: Check the filter each month and change it when it looks dirty or every three months, whichever comes first.
  • Check the furnace flue: Examine the exterior vent for obstructions and clear out any you find.
  • Don’t store combustible items near the furnace: Things such as cardboard boxes, paper, clothing and other combustibles should be kept at a minimum 3 feet away from the furnace and any other heating equipment.
  • Install a flame rollout switch: This safety system recognizes if a fire or hot exhaust gases are inside your furnace’s burner compartment. If the rollout switch trips, have your furnace inspected right away to diagnose and repair the problem before it causes a furnace fire.
  • Request annual furnace maintenance: It isn’t always easy to recognize if your furnace is performing unsafely. Whether you notice warning signs or not, prioritize furnace maintenance every fall.

Schedule Furnace Services Today

Is it time for your yearly tune-up? Do you need help fixing a problem with your furnace? Whatever is happening, Matz-Rightway is here for you. Our HVAC professionals can inspect, clean and test the system to ensure safe operation. If anything doesn't seem right, we’ll recommend a repair or a modification, providing you peace of mind that your furnace is unlikely to catch fire. For more information or to schedule furnace maintenance, please contact your local Matz-Rightway office today.

 

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