Question 205Steam Plants - 1st Asst/Chief

The correct answer is C) shut off the fuel supply if flame failure is detected. Flame scanners are used in boiler combustion control systems to continuously monitor the quality of the flame in the boiler. If the flame scanner detects a flame failure, it will automatically shut off the fuel supply to the boiler. This is a critical safety feature to prevent unburned fuel from accumulating, which could lead to a dangerous explosion or fire. The other answer choices are incorrect because they do not accurately describe the primary function of flame scanners in boiler combustion control systems. Flame scanners are not used to secure fuel oil pumps, regulate the fuel/air ratio, or secure the forced draft fan - their sole purpose is to detect flame failure and shut off the fuel supply in such an event.