Can Furnaces Catch Fire?

The return of cold temperatures raises your dependency on home heating equipment in the fall. If your furnace isn’t working correctly, it could grow to be a fire hazard and threaten your family’s safety. 

As stated by the National Fire Protection Association (NFPA), heating systems are a leading cause of home fires, leading to approximately 50,000 blazes, 500 civilian deaths and more than $1 billion in significant property damage every year. Space heaters and fireplaces cause the majority of fires affecting heating equipment, but central heaters, including furnaces, are liable for about 12% of these blazes. Learn more about the primary causes of furnace fires and how to prevent them. 

Causes of Furnace Fires

Old furnaces are more exposed to safety concerns because they may be manufactured differently and settle into disrepair through the years. Nevertheless, whether your furnace is more than a decade old or brand new, you should be familiar with these causes of furnace fires. 

Overheated Motor

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

• A clogged filter can restrict airflow and cause the motor to work longer. At some point, the motor might overheat, raising the risk of fire. 
• Dirt can gather around and cover up the motor, forcing it to hold heat, which can cause a fire. 
• Exposed or corroded wiring can cause the voltage to elevate, increasing the chances of an electrical fire. 
• Overly tight or worn motor bearings can heat up when the furnace runs. Without the appropriate lubrication, the bearings may eventually catch fire. 

Obstructed Furnace Flue 

Yard debris, animal nests and other materials can block the furnace flue, restricting oxygen. This causes soot buildup and bad ventilation, decreasing efficiency and raising the risk of flame rollout. Flame rollout is when fire reaches past the heat exchanger and burns the parts in your furnace. If this problem remains, your heating equipment can be seriously 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 is exchanged to the air circulating through your home. A heat exchanger blocked with soot or corrosion has the same impact as a blocked furnace flue—reduced performance and a higher risk of flame rollout. 

Cracked Heat Exchanger 

Various problems occur if corrosion cracks the heat exchanger. First, it reduces suction within this chamber, resulting in less airflow and increased flame rollout. Second, it emits fumes, including carbon monoxide, into your home. Inhaling CO gas can be deadly, so never dismiss your carbon monoxide alarms. CO gas can also return to the source of the leak and ignite if a flame is lit. 

Inadequate Gas Pressure 

Furnaces need a precise mixture 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. 

Conversely, high gas pressure can create excessive heat inside the furnace, which can cause the soot inside the heat exchanger to ignite. Such fires can easily spread to other areas. 

How to Prevent Furnace Fires 

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

• Change the air filter regularly: 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 such as cardboard boxes, paper, clothing and other combustibles should be kept more than 3 feet away from the furnace and all 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 triggers, have your furnace inspected promptly 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, remember furnace maintenance every fall. 

Schedule Furnace Services Today 

Is it time for your annual tune-up? Do you need help taking care of a problem with your furnace? Whatever the case, Service Experts Heating, Air Conditioning & Plumbing 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 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 Service Experts Heating, Air Conditioning & Plumbing office today.