Question 746Steam Plants - Assistant Engineer

The correct answer is C) a perforated heating coil. When steam is admitted to a fuel oil double bottom tank, the level of the contaminated drain inspection tank will continuously decrease due to a leak in the heating coil. This indicates that the heating coil is perforated, allowing the steam to escape into the fuel oil tank rather than heating the oil as intended. The other options are incorrect because: A) A plugged heating coil would not cause the level of the contaminated drain inspection tank to decrease. B) Higher than normal return temperatures would not be the direct cause of the decreasing level in the inspection tank. D) A leaking makeup feed regulator would not directly affect the level of the contaminated drain inspection tank.