Question 432Steam Plants - Assistant Engineer70% to pass
Which of the conditions listed may be indicated by the lifting of the DC heater relief valve?
AI Explanation
The correct answer is D) A malfunctioning auxiliary exhaust make-up steam regulating valve.
The lifting of the DC heater relief valve indicates that there is excessive pressure buildup in the DC heater, which is typically caused by a malfunctioning auxiliary exhaust make-up steam regulating valve. This valve is responsible for controlling the flow of steam into the DC heater, and if it is not functioning properly, it can lead to an excessive buildup of pressure, causing the relief valve to lift.
The other answer choices are incorrect because they do not directly relate to the lifting of the DC heater relief valve. Excessive deaeration of the feed water (A) or low back pressure in the auxiliary exhaust line (B) would not cause the relief valve to lift. A low water level continually maintained in the DC heater (C) would not lead to the relief valve lifting either, as the relief valve is designed to prevent excessive pressure buildup, not to address water level issues.
Related Questions
#430 Lower boiler efficiency results from carrying too much excess air because _______________.#431 If the flue gas oxygen content is too high, you should _______________.#433 The water level in a steaming boiler has risen to within 2 inches from the top of the gage glass. Your immediate action should be to _______________.#434 In a closed feed and water cycle, which of the conditions listed could prevent vacuum from reaching the desired level? #435 If the DC heater relief valve lifts frequently, the cause can be excessive _______________.