The return of cooler temperatures boosts your dependence on home heating equipment in the fall. If your furnace isn’t functioning correctly, it could develop into a fire hazard and jeopardize your family’s safety.
As stated by the National Fire Protection Association (NFPA), heating systems like furnaces are a leading source of home fires, causing nearly 50,000 blazes, 500 civilian deaths and more than $1 billion in significant property damage annually. Space heaters and fireplaces start most of the fires involving heating equipment, but central heaters, including furnaces, are liable for around 12% of these blazes. Find out more about the leading causes of furnace fires and how to avoid them.
Causes of Furnace Fires
Old furnaces are more susceptible to safety hazards as they could be configured differently and slide into disrepair over the years. Still, whether your furnace is more than a decade old or brand new, you should know about these causes of furnace fires.
Overheating Motor
A furnace motor can overheat in several ways. Here are the biggest risks:
- A clogged filter can impede airflow and cause the motor to work harder. Sooner or later, the motor might overheat, elevating the risk of fire.
- Dirt can gather around and coat the motor, forcing it to retain heat, which can trigger a fire.
- Exposed or damaged wiring can cause the voltage to get too high, increasing the risk of an electrical fire.
- Exceedingly tight or damaged motor bearings can heat up whenever the furnace starts. Without adequate lubrication, the bearings could eventually light on fire.
Clogged Furnace Flue
Yard debris, animal nests and other obstructions can block the furnace flue, restricting oxygen. This leads to soot buildup and improper ventilation, lowering efficiency and increasing the risk of flame rollout. Flame rollout is when fire escapes the heat exchanger and burns the parts inside your furnace. If this problem persists, your heating equipment may be seriously damaged, and the fire could spread to areas outside the furnace.
Obstructed Heat Exchanger
The heat exchanger is a closed combustion chamber where the heat created by your furnace is exchanged 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 a bigger risk of flame rollout.
Cracked Heat Exchanger
Several problems can happen if corrosion breaks the heat exchanger. First, it affects suction within this chamber, resulting in less airflow and increased flame rollout. Second, it emits fumes, such as carbon monoxide, into your home. Breathing CO gas can be fatal, so never ignore your carbon monoxide alarms. CO gas can also return to the source of the leak and ignite if a flame is found.
Inadequate Gas Pressure
Furnaces require an exact 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 causes unwanted condensation in the heat exchanger, accelerating the rate of corrosion.
On the other hand, high gas pressure can produce excessive heat inside the furnace, which can cause the soot inside the heat exchanger to ignite. Such fires can readily spread to other areas.
How to Prevent Furnace Fires
Based on the listed ways a furnace can catch fire, here are the steps you can take to prevent furnace fires:
- Replace the air filter on a regular basis: Check the filter each month and change it when it appears dirty or every three months, whichever comes first.
- Check the furnace flue: Inspect the exterior vent for obstructions and remove any you find.
- Don’t place combustible items close to the furnace: Things such as cardboard boxes, paper, clothing and other combustibles should be kept more than 3 feet away from the furnace and any other heating equipment.
- Install a flame rollout switch: This safety component 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 produces a furnace fire.
- Schedule yearly furnace maintenance: It isn’t always easy to tell if your furnace is working unsafely. Whether you notice warning signs or not, remember 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, San Antonio Air Service Experts is here for you. Our HVAC pros can inspect, clean and test the system to guarantee safe operation. If anything doesn't seem right, we’ll perform a repair or a modification, offering you peace of mind that your furnace is unlikely to catch fire. For more information or to schedule furnace maintenance,
please contact your local San Antonio Air Service Experts office today.