Can Furnaces Catch Fire?

The return of cooler temperatures increases your dependence on home heating equipment every fall. If your furnace isn’t operating properly, it might grow to be a fire hazard and threaten your family’s safety. 

As stated by the National Fire Protection Association (NFPA), heating equipment is a major source of home fires, contributing to nearly 50,000 blazes, 500 civilian deaths and more than $1 billion in direct property damage annually. Space heaters and fireplaces generate most of the fires concerning heating equipment, but central heaters, including furnaces, are accountable for just about 12% of these blazes. Learn more about the most likely causes of furnace fires and how to avoid them. 

Causes of Furnace Fires

Aging furnaces are more exposed to safety problems because 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. 

Overheated Motor

A furnace motor can overheat in several ways. Here are the most common risks:  

• A clogged filter can restrict airflow and force the motor to work longer. Eventually, the motor might overheat, increasing the risk of fire. 
• Dirt can accumulate around and coat the motor, forcing it to absorb heat, which can cause a fire. 
• Exposed or deteriorated wiring can cause the voltage to elevate, increasing the likelihood of an electrical fire. 
• Exceedingly tight or damaged motor bearings can heat up when the furnace is on. Without the proper lubrication, the bearings could eventually catch fire. 

Clogged Furnace Flue 

Yard debris, animal nests and other materials can obstruct the furnace flue, restricting oxygen. This results in soot accumulation and improper ventilation, lowering efficiency and increasing the risk of flame rollout. Flame rollout is when fire reaches past the heat exchanger and burns the parts inside your furnace. If this problem persists, your heating equipment may be badly damaged, and the fire can spread to areas outside the furnace. 

Obstructed Heat Exchanger 

The heat exchanger is a sealed combustion chamber where the heat produced by your furnace transfers to the air circulating within your home. A heat exchanger blocked 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 

Various problems can happen if corrosion breaks the heat exchanger. First, it reduces suction within this chamber, leading to less airflow and increased flame rollout. Second, it emits fumes, such as carbon monoxide, into your home. Breathing in CO gas can be deadly, so never ignore 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 need an exact combination of natural gas and air to generate 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 inside the heat exchanger, accelerating the rate of corrosion. 

On the other hand, high gas pressure can lead to excessive heat within the furnace, which can cause the soot inside the heat exchanger to burn. Such fires can readily spread to other areas. 

How to Prevent Furnace Fires 

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

• Change the air filter on a regular basis: Check the filter each month and change it when it looks dirty or every three months, whichever comes first. 
• Keep an eye on the furnace flue: Periodically check the exterior vent for obstructions and take care of any you find. 
• Don’t keep combustible items around the furnace: Things including cardboard boxes, paper, clothing and other combustibles should be kept at least 3 feet away from the furnace and any other heating equipment. 
• Put in 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 right away to diagnose and repair the problem before it causes a furnace fire. 

• Schedule annual furnace maintenance: It isn’t always easy to recognize 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 annual tune-up? Do you need help fixing a problem with your furnace? Whatever is happening, Service Experts Heating, Air Conditioning & Plumbing is here for you. Our HVAC experts can inspect, clean and test the system to ensure safe operation. If anything seems off, we’ll recommend a repair or a modification, giving you peace of mind that your furnace is unlikely to catch fire. For more info or to schedule furnace maintenance, please contact your local Service Experts Heating, Air Conditioning & Plumbing office today.