Can Furnaces Catch Fire?

The return of cold temperatures raises your reliance on home heating equipment every fall. If your furnace isn’t functioning correctly, it might grow to be a fire hazard and threaten your family’s safety. 

As stated by the National Fire Protection Association (NFPA), heating systems like furnaces are a major factor 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 generate the majority of fires affecting heating equipment, but central heaters, including furnaces, are accountable for just about 12% of these blazes. Learn the most likely causes of furnace fires and how to minimize them. 

Causes of Furnace Fires

Old furnaces are more exposed to safety hazards because they might be manufactured 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 be familiar with these causes of furnace fires. 

An Overheated Motor

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

• A clogged filter can block airflow and force the motor to work longer. Sooner or later, the motor can overheat, raising the risk of fire. 
• Dirt can gather around and coat the motor, forcing it to retain heat, which can cause a fire. 
• Exposed or corroded wiring can cause the voltage to increase too much, increasing the chances of an electrical fire. 
• Exceedingly tight or damaged motor bearings can heat up as the furnace starts. Without the appropriate lubrication, the bearings may eventually catch fire. 

Blocked Furnace Flue 

Yard waste, animal nests and other materials can block the furnace flue, lowering oxygen. This causes soot accumulation and weaker ventilation, decreasing 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 remains, your heating equipment may be seriously damaged, and the fire can spread to areas outside the furnace. 

Clogged Heat Exchanger 

The heat exchanger is a sealed combustion chamber where the heat generated by your furnace transfers to the air circulating within your home. A heat exchanger clogged up with soot or corrosion has the same result as a blocked furnace flue—reduced performance and a higher risk of flame rollout. 

Cracked Heat Exchanger 

Various problems can take place if corrosion damages the heat exchanger. First, it affects suction within this chamber, leading to less airflow and increased flame rollout. Second, it produces fumes, like carbon monoxide, into your home. Breathing 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. 

Improper Gas Pressure 

Furnaces need an accurate 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, accelerating the rate of corrosion. 

On the other hand, high gas pressure can create excessive heat in the furnace, which can cause the soot inside the heat exchanger to burn. Such fires can quickly 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: 

• Change the air filter regularly: Check the filter once a month and change it when it seems dirty or every three months, whichever comes first. 
• Keep an eye on the furnace flue: Examine the exterior vent for obstructions and clear out any you find. 
• Don’t store combustible items close to the furnace: Things like cardboard boxes, paper, clothing and other combustibles should be kept at a minimum 3 feet away from the furnace and all other heating equipment. 
• Add a flame rollout switch: This safety device detects if a fire or hot exhaust gases are inside your furnace’s burner compartment. If the rollout switch trips, have your furnace inspected promptly to diagnose and repair the problem before it produces a furnace fire. 

• Request annual furnace maintenance: It isn’t always easy to tell if your furnace is performing 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 is happening, Service Experts Heating, Air Conditioning & Plumbing is here for you. Our HVAC pros can inspect, clean and test the system to ensure safe operation. If anything looks out of place, we’ll perform a repair or a modification, giving 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.