What Causes Flame Rollout on a Furnace?

Don't let common furnace issues leave you in the cold. Contact Fast Air Repair for quick, reliable service! 

Furnaces can pose a significant fire risk to your home if you don't provide the proper care and maintenance to your HVAC system. One of the biggest concerns for homeowners and HVAC technicians alike is flame rollout. What is this issue, and what can you do to prevent it?

Learn what causes flame rollout on a furnace in this helpful guide. If your furnace exhibits any signs of flame rollout, contact the team at Fast Air Repair. We specialize in all things heating and cooling in Ocala and will get your furnace working properly following an inspection. 

What Is Flame Rollout?

Modern gas furnaces emit flames from the burners, which kickstart the rest of the heating process. Normally, the combustion chamber conceals these flames and the gases they produce. When the gases and sparks move outside the combustion chamber, it's known as flame rollout. 

This presents many furnace safety concerns and can cause long-term damage to your system. It's critical that you understand the causes of flame rollout in heating systems and take steps to prevent it. 

What Causes Flame Rollout on a Furnace?

Experts need to perform repairs due to a few common furnace flame rollout reasons. Understanding the top causes of flame rollout can help you prevent damage to your furnace and keep your home safer. Below is a breakdown of the issues that often lead to this problem. 

A Buildup of Soot and Gases

Over time, your furnace's combustion chamber accumulates large amounts of soot and harmful gases. A high concentration of gases within the chamber will cause the flames to grow bigger each time you turn the furnace on.

Flame rollout is extremely dangerous because it involves burning toxic gases like carbon monoxide instead of clean natural gas. You'll need to keep the combustion chamber free of soot and flue gases to reduce fire hazards and prevent damage to the furnace. 

Flue Pipe Blockage

When you ask an expert, "What causes flame rollout on a furnace?" they'll tell you that a blocked flue pipe is a common cause. The normal furnace operation involves the following cycle for flue gases:

1. Gases burn in the combustion chamber and release smoke, soot, and flue gases. 
2. The heat exchanger filters the flue gases and sends them through a separate passageway. 
3. That passageway leads to the exterior vent pipe and goes outside your home with other exhaust fumes. 

Any type of blockage or debris in the exterior vent pipe can produce a buildup of gases inside the HVAC system. Your furnace is more likely to experience flame rollout when twigs, leaves, or animals block the path inside the flue pipe. 

Cracked Heat Exchanger

A key factor in identifying furnace flame issues is inspecting the furnace's internal components, such as the heat exchanger. The heat exchanger acts as a shield between the combustion chamber and the blower fan. It filters out harmful flue gases so only safe, heated air enters your home's vents. 

The heat exchanger may crack due to temperature fluctuations or overheating. When this happens, gases like carbon monoxide can flow out of the combustion chamber and through your air ducts. As the furnace flame continues to burn, it may lead to flame rollout due to the heat exchanger no longer containing flue gases. 

An excellent way to prevent this from happening is to invest in a furnace with multiple heat exchangers. These modern heaters not only keep you safe from dangerous gases, but they can make your home more energy efficient as well. 

The Dangers of Furnace Flame Rollout

Once you know what causes flame rollout on a furnace, you'll be better equipped to prevent it. Flame rollout is a major concern because of both fire and health hazards. 

Say your furnace has a cracked heat exchanger that produces flame rollout. Not only will components like wiring and gas valves be exposed to open flames, but the holes within the heat exchanger can release toxic carbon monoxide. In this scenario, your health is put in jeopardy, and your home could catch on fire because the flames won't be concealed in the combustion chamber. 

Furnace manufacturers combat this problem by equipping each unit with a flame sensor. When the internal temperature of the furnace reaches unsafe levels, the sensor automatically turns off the furnace so it can cool down. Furnaces also have a flame rollout switch, which stops the flow of gas once the temperature outside the combustion chamber reaches unsafe levels. 

Flame Rollout Prevention Tips

As a homeowner, there's very little you can do in terms of flame rollout troubleshooting. Once you experience this issue, it will likely continue until you schedule repair services. Technicians will need to replace a cracked heat exchanger or clean the exhaust pipe and combustion chamber to alleviate the problem. 

You can prevent this issue altogether by scheduling routine furnace maintenance. Experts recommend having an inspection every year before the start of the heating season. A furnace tune-up service is thorough and involves the following:

• Checking the function of internal components
• Cleaning parts like the air filter, flame sensor, and combustion chamber
• Inspecting electrical connections and gas valves
• Repairing minor damage on the spot

Regular maintenance appointments keep your furnace running efficiently and save you money on both energy costs and future repairs. You'll have peace of mind that your heater operates properly. 

Choose Fast Air Repair for Reliable Furnace Services

Now that you know what causes flame rollout on a furnace make sure you take care of your heating system by scheduling regular maintenance. Keep an eye out for issues with your heater's performance, as it could indicate problems with the furnace limit switch, heat exchanger, or other vital components. 



Reach out to Fast Air Repair if your furnace starts malfunctioning. We are available 24 hours a day for emergency services. Call us at (352) 290-7968 to schedule an appointment for your HVAC system.