Can Furnaces Catch Fire?

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

As reported by the National Fire Protection Association (NFPA), heating systems are a leading factor of home fires, causing approximately 50,000 blazes, 500 civilian deaths and more than $1 billion in direct property damage each year. Space heaters and fireplaces start the majority of fires involving heating equipment, but central heaters, including furnaces, are responsible for just about 12% of these blazes. Learn the leading causes of furnace fires and how to prevent them. 

Causes of Furnace Fires

Old furnaces are more vulnerable to safety problems as they may be configured differently and slide into disrepair through the years. That being said, 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 different ways. Here are the most common risks:  

• A clogged filter can impede airflow and cause the motor to work more. Eventually, the motor might overheat, elevating the risk of fire. 
• Dirt can gather around and cover up 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. 
• Overly tight or damaged motor bearings can heat up whenever the furnace runs. Without adequate lubrication, the bearings can eventually light on fire. 

Clogged Furnace Flue 

Yard debris, animal nests and other materials can clog the furnace flue, reducing oxygen. This leads to soot building up and weaker 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 in your furnace. If this problem persists, your heating equipment can be badly damaged, and the fire can spread to areas outside the furnace. 

Clogged Heat Exchanger 

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

Cracked Heat Exchanger 

Numerous problems can happen if corrosion breaks the heat exchanger. First, it lowers suction inside this chamber, triggering less airflow and increased flame rollout. Second, it releases fumes, including carbon monoxide, into your home. Inhaling CO gas can be deadly, so never neglect your carbon monoxide alarms. CO gas can also flash back to the source of the leak and ignite if a flame is found. 

Improper Gas Pressure 

Furnaces need an accurate mixture of natural gas and air to produce 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, accelerating the rate of corrosion. 

On the other hand, high gas pressure can produce excessive heat within 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 light on fire, here are the steps you can take to prevent furnace fires: 

• Change the air filter consistently: Check the filter each month and change it when it appears dirty or every three months, whichever comes first. 
• Check the furnace flue: Examine the exterior vent for obstructions and take care of any you find. 
• Don’t place combustible items close to 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. 
• Install a flame rollout switch: This safety system detects if a fire or hot exhaust gases are inside your furnace’s burner compartment. If the rollout switch triggers, have your furnace inspected as soon as possible to diagnose and repair the problem before it causes a furnace fire. 

• Schedule annual furnace maintenance: It isn’t always easy to notice 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 taking care of a problem with your furnace? Whatever is happening, Service Experts Heating, Air Conditioning & Plumbing is here for you. Our HVAC professionals can inspect, clean and test the system to provide safe operation. If anything seems off, we’ll perform a repair or a modification, offering you peace of mind that your furnace is unlikely to catch fire. For more details or to schedule furnace maintenance, please contact your local Service Experts Heating, Air Conditioning & Plumbing office today.