Question 169Motor Plants - 1st Asst/Chief

The correct answer is A) The fusible plugs will melt. When the water level in a fire-tube type auxiliary boiler approaches the crown sheet (the top of the furnace), the fusible plugs installed on the boiler will melt. These plugs are designed to melt at a specific temperature, typically around 250°F, to prevent the crown sheet from overheating and potentially causing an explosion. The other options are incorrect because: B) The furnace will not explode if the fusible plugs function as designed, C) The furnace will overheat if the water level is too low, and D) Excess steam will not be generated if the fusible plugs melt, as this action is intended to prevent further overheating and damage to the boiler.