What is a common symptom of flame rollout in a gas furnace?

A common symptom of flame rollout in a gas furnace is the presence of flames or heat outside the combustion chamber. This condition occurs when the combustion gases do not properly exit the furnace through the venting system, causing flames to escape into areas where they shouldn't be. This can pose a serious safety hazard as it may indicate improper venting or blockages, potentially leading to fire risks or damage to the furnace itself.

When flame rollout occurs, it’s typically associated with issues such as a malfunctioning heat exchanger, blockages within the venting system, or improper installation of the furnace. Observing flames or excessive heat in areas outside the furnace is a clear and alarming indicator that the combustion process is not functioning correctly, stemming from inadequate air supply, venting issues, or other malfunctions within the furnace. Addressing this symptom promptly is crucial to ensure safety and proper operation of the heating system.