Can Furnaces Catch Fire?

The return of cooler temperatures increases your dependency on home heating equipment every fall. If your furnace isn’t working correctly, it could grow to be a fire hazard and endanger your family’s safety. 

As stated by the National Fire Protection Association (NFPA), heating systems like furnaces are a major cause of home fires, contributing to almost 50,000 blazes, 500 civilian deaths and more than $1 billion in significant property damage every year. Space heaters and fireplaces start the majority of fires concerning heating equipment, but central heaters, including furnaces, are responsible for around 12% of these blazes. Learn the leading causes of furnace fires and how to minimize them. 

Causes of Furnace Fires

Aging furnaces are more exposed to safety concerns since they might be configured differently and settle 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. 

Overheating Motor

A furnace motor can overheat in various ways. Here are the main risks:  

• A clogged filter can block airflow and cause the motor to work longer. Sooner or later, the motor can 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. 
• Overly tight or damaged motor bearings can heat up as the furnace is on. Without adequate lubrication, the bearings can eventually catch fire. 

Blocked Furnace Flue 

Yard waste, animal nests and other obstructions can block the furnace flue, restricting oxygen. This causes soot buildup and improper ventilation, limiting efficiency and increasing the risk of flame rollout. Flame rollout is when fire escapes the heat exchanger and burns the parts within your furnace. If this problem continues, your heating equipment may be severely damaged, and the fire may even spread to areas outside the furnace. 

Obstructed Heat Exchanger 

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

Cracked Heat Exchanger 

Numerous problems can take place if corrosion cracks the heat exchanger. First, it reduces suction within this chamber, triggering less airflow and increased flame rollout. Second, it releases fumes, such as carbon monoxide, into your home. Breathing CO gas can be deadly, so never dismiss your carbon monoxide alarms. CO gas can also flash back to the source of the leak and ignite if a flame is present. 

Inadequate Gas Pressure 

Furnaces need a precise 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 produces unwanted condensation inside the heat exchanger, accelerating the rate of corrosion. 

Conversely, 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 different ways a furnace can combust, here are the steps you can take to avoid furnace fires: 

• Replace the air filter consistently: 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: Inspect the exterior vent for obstructions and remove any you find. 
• Don’t keep combustible items close to the furnace: Things including cardboard boxes, paper, clothing and other combustibles should be kept at a minimum 3 feet away from the furnace and all other heating equipment. 
• Put in a flame rollout switch: This safety device recognizes if a fire or hot exhaust gases are inside your furnace’s burner compartment. If the rollout switch triggers, have your furnace inspected right away 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 performing 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 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 provide safe operation. If anything looks out of place, we’ll suggest 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.