Question 24Steam Plants - Assistant Engineer

The correct answer is A) high solids content and foaming in the drum. In a boiler equipped with an automatic feed water regulator, erratic variations in the water level are typically caused by high solids content and foaming in the drum. This is because the high solids content can lead to increased foaming, which can disrupt the normal operation of the feed water regulator and cause the water level to fluctuate erratically. The other options are incorrect because: B) High feed water temperature would not directly cause erratic water level variations. C) A ruptured feed water control valve diaphragm would likely result in a more consistent water level issue, not erratic variations. D) Low feed water temperature would not be the primary cause of erratic water level changes in a boiler with an automatic feed water regulator.