Question 314Steam Plants - Assistant Engineer

The correct answer is C) the furnace to be purged. Combustion control systems on automatic boilers are designed to prevent immediate burner ignition after a normal or safety shutdown in order to allow time for the furnace to be purged. This is a safety measure to ensure that any unburned fuel or gases are cleared from the furnace before the burner is reignited, preventing the risk of explosions or fires. The other answer choices are incorrect because they do not address the primary purpose of the combustion control system, which is to allow for furnace purging. Specifically, A) the fuel pump starting and B) the drum level equalizing are not directly related to the furnace purging process, while D) electric charge buildup in the igniter is not a concern that the combustion control system is designed to address.