Can Furnaces Catch Fire?

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

As reported by the National Fire Protection Association (NFPA), heating systems like furnaces are a leading factor of home fires, causing almost 50,000 blazes, 500 civilian deaths and more than $1 billion in significant property damage annually. Space heaters and fireplaces generate the majority of fires affecting heating equipment, but central heaters, such as furnaces, are responsible for about 12% of these blazes. Find out more about the most likely causes of furnace fires and how to prevent them. 

Causes of Furnace Fires

Old furnaces are more susceptible to safety hazards because they might be manufactured differently and fall 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. 

Overheated Motor

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

• A clogged filter can block airflow and force the motor to work harder. Sooner or later, the motor might overheat, elevating the risk of fire. 
• Dirt can collect around and coat the motor, forcing it to absorb heat, which can lead to a fire. 
• Exposed or deteriorated wiring can cause the voltage to elevate, increasing the risk of an electrical fire. 
• Excessively tight or worn motor bearings can heat up as the furnace starts. Without the proper lubrication, the bearings can eventually catch fire. 

Obstructed Furnace Flue 

Yard debris, animal nests and other materials can block the furnace flue, reducing oxygen. This leads to soot buildup and improper ventilation, lowering efficiency and raising the risk of flame rollout. Flame rollout is when fire gets out of the heat exchanger and burns the parts within your furnace. If this problem continues, your heating equipment could be badly damaged, and the fire can 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 within your home. A heat exchanger clogged with soot or corrosion has the same impact as a blocked furnace flue—reduced performance and an increased risk of flame rollout. 

Cracked Heat Exchanger 

Various problems can take place if corrosion damages the heat exchanger. First, it reduces suction in this chamber, leading to less airflow and increased flame rollout. Second, it emits fumes, such as carbon monoxide, into your home. Breathing CO gas can be lethal, so never dismiss your carbon monoxide alarms. CO gas can also return to the source of the leak and ignite if a flame is present. 

Improper Gas Pressure 

Furnaces require an exact mixture of natural gas and air to ensure 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 leads to unwanted condensation within the heat exchanger, increasing the rate of corrosion. 

Conversely, 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 various ways a furnace can catch fire, here are the steps you can take to prevent furnace fires: 

• Replace the air filter consistently: Check the filter once a 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 remove any you find. 
• Don’t keep combustible items around the furnace: Things like 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 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 as soon as possible to diagnose and repair the problem before it results in a furnace fire. 

• Schedule yearly furnace maintenance: It isn’t always easy to recognize 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 yearly 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 pros can inspect, clean and test the system to provide safe operation. If anything looks out of place, we’ll suggest a repair or a modification, giving 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.