The return of cold temperatures boosts your dependence on home heating equipment each fall. If your furnace isn’t functioning correctly, 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 top source 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, like furnaces, are responsible for about 12% of these blazes. Learn the primary causes of furnace fires and how to avoid them.
Causes of Furnace Fires
Aging furnaces are more vulnerable to safety problems because they might be designed differently and settle into disrepair over the years. Nevertheless, 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 different ways. Here are the most common risks:
- A clogged filter can impede airflow and cause the motor to work harder. Sooner or later, the motor may overheat, increasing the risk of fire.
- Dirt can accumulate around and coat the motor, forcing it to hold heat, which can trigger a fire.
- Exposed or deteriorated wiring can cause the voltage to increase too much, increasing the risk of an electrical fire.
- Excessively tight or damaged motor bearings can heat up as the furnace is on. Without the appropriate lubrication, the bearings can eventually light on fire.
Obstructed Furnace Flue
Yard debris, animal nests and other obstructions can clog the furnace flue, lowering oxygen. This results in soot buildup and weaker ventilation, decreasing efficiency and increasing the risk of flame rollout. Flame rollout is when fire gets out of the heat exchanger and burns the parts inside your furnace. If this problem remains, your heating equipment can be badly damaged, and the fire could spread to areas outside the furnace.
Clogged Heat Exchanger
The heat exchanger is a closed combustion chamber where the heat created by your furnace is moved to the air circulating throughout your home. A heat exchanger clogged up with soot or corrosion has the same effect as a blocked furnace flue—reduced performance and an increased risk of flame rollout.
Cracked Heat Exchanger
Numerous problems can take place if corrosion breaks the heat exchanger. First, it reduces suction within this chamber, triggering less airflow and increased flame rollout. Second, it produces fumes, like carbon monoxide, into your home. Breathing CO gas can be deadly, 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 present.
Improper Gas Pressure
Furnaces require an accurate mixture of natural gas and air to ensure safe and efficient combustion. Too little pressure is often the result of clogged burner orifices. This problem makes the burner flames more likely to roll out. It also causes unwanted condensation within the heat exchanger, increasing the rate of corrosion.
Conversely, high gas pressure can lead to excessive heat in the furnace, which can cause the soot inside the heat exchanger to burn. Such fires can easily spread to other areas.
How to Prevent Furnace Fires
Based on the different ways a furnace can catch fire, here are the steps you can take to avoid furnace fires:
- Change the air filter on a regular basis: Check the filter once a month and change it when it looks dirty or every three months, whichever comes first.
- Check the furnace flue: Periodically check the exterior vent for obstructions and take care of any you find.
- Don’t place combustible items close to the furnace: Things like cardboard boxes, paper, clothing and other combustibles should be kept at least 3 feet away from the furnace and all other heating equipment.
- Install a flame rollout switch: This safety component detects if a fire or hot exhaust gases are inside your furnace’s burner compartment. If the rollout switch trips, have your furnace inspected as soon as possible to diagnose and repair the problem before it results in a furnace fire.
- Request yearly furnace maintenance: It isn’t always easy to tell if your furnace is operating 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 the case, Climate Control Service Experts is here for you. Our HVAC professionals can inspect, clean and test the system to provide safe operation. If anything looks out of place, 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 Climate Control Service Experts office