What is a condition that can lead to puff-back in a burner?

The condition that can lead to puff-back in a burner is characterized by pure white condensed steam that emits a smell resembling fuel oil. Puff-back occurs when there is improper combustion or delayed ignition inside the burner chamber, causing a buildup of unburned fuel. When this fuel ignites, it can create a backfire effect, which forces gases and flames back out through the burner assembly, often resulting in a puffing sound or explosion.

The presence of white steam that has a distinct fuel oil odor indicates incomplete combustion and the potential for excess fuel accumulation in the combustion chamber. This environment is conducive to conditions that can transition into a puff-back scenario, where ignition occurs after a delay, leading to the dangerous and explosive release of combustion gases.

Thus, identifying the odors and characteristics of combustion byproducts, such as the pure white condensed steam with a recognizable fuel oil smell, is crucial for operators to prevent puff-back incidents and ensure safe burner operation.