What common hazard is associated with the failure to purge the furnace in a boiler?

Failure to purge the furnace in a boiler can lead to a buildup of combustible gases, primarily gas or vapor that may not have been completely expelled from the furnace before ignition. When these gases accumulate and are ignited, they can create a rapid combustion that results in a furnace explosion. This hazard underscores the importance of proper operating procedures, which include purging the furnace to ensure that any unburned fuel is removed and that the combustion chamber is filled with appropriate air before starting the burner.

Implementing proper purging practices creates a safer environment when operating a boiler, minimizing the risk of explosions and ensuring that the combustion process is controlled and efficient.