Can Furnaces Catch Fire?

The return of cooler temperatures increases your dependency on home heating equipment each 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 major cause of home fires, contributing to nearly 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, such as furnaces, are accountable for just about 12% of these blazes. Learn the leading causes of furnace fires and how to minimize them. 

Causes of Furnace Fires

Older furnaces are more susceptible to safety problems because they could be manufactured differently and settle into disrepair over the years. Nevertheless, whether your furnace is more than a decade old or brand new, you should know about these causes of furnace fires. 

An Overheated Motor

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

• A clogged filter can impede airflow and force the motor to work more. Sooner or later, the motor can overheat, elevating the risk of fire. 
• Dirt can accumulate around and coat the motor, forcing it to hold heat, which can cause a fire. 
• Exposed or deteriorated wiring can cause the voltage to get too high, increasing the likelihood of an electrical fire. 
• Overly tight or worn motor bearings can heat up when the furnace runs. Without adequate lubrication, the bearings could eventually catch fire. 

Blocked Furnace Flue 

Yard debris, animal nests and other materials can clog the furnace flue, lowering oxygen. This results in soot accumulation and improper ventilation, lowering efficiency and raising the risk of flame rollout. Flame rollout is when fire escapes the heat exchanger and burns the parts inside your furnace. If this problem continues, your heating equipment may be seriously damaged, and the fire could spread to areas outside the furnace. 

Obstructed Heat Exchanger 

The heat exchanger is a restricted combustion chamber where the heat produced 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 

Several problems occur if corrosion cracks the heat exchanger. First, it affects suction in this chamber, resulting in less airflow and increased flame rollout. Second, it emits fumes, including carbon monoxide, into your home. Breathing in CO gas can be lethal, so never neglect your carbon monoxide alarms. CO gas can also return to the source of the leak and ignite if a flame is found. 

Improper Gas Pressure 

Furnaces require an exact combination of natural gas and air to generate 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 in the heat exchanger, increasing the rate of corrosion. 

Conversely, high gas pressure can produce excessive heat within the furnace, which can cause the soot inside the heat exchanger to combust. Such fires can quickly 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 avoid furnace fires: 

• Change the air filter regularly: Check the filter monthly and change it when it appears dirty or every three months, whichever comes first. 
• Keep an eye on the furnace flue: Examine the exterior vent for obstructions and remove any you find. 
• Don’t place combustible items near the furnace: Things including 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 device detects 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 produces a furnace fire. 

• Schedule yearly furnace maintenance: It isn’t always easy to tell if your furnace is working 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 guarantee 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 details or to schedule furnace maintenance, please contact your local Service Experts Heating, Air Conditioning & Plumbing office today.