Question 444Electricity/Electronics - QMED70% to pass
As shown in figure "A" and "B" of the illustration, the potable water pump is short- cycling by the action of the pressure switch as a result of an unusually high level in the potable water hydro-pneumatic header tank. What is most likely the cause? Illustration EL-0043
AI Explanation
The correct answer is D) The potable water hydro-pneumatic header tank is in need of recharging with compressed air due to absorption of air into the water over time.
This is the correct answer because the short-cycling of the potable water pump is likely caused by a loss of the proper air-to-water ratio in the hydro-pneumatic header tank. Over time, air can be absorbed into the water, reducing the air cushion and causing the pressure switch to cycle too frequently as the water level rises and falls. Recharging the tank with compressed air will restore the proper air-to-water ratio and stop the short-cycling.
The other answer choices are incorrect because they do not address the underlying issue of the air-to-water ratio in the hydro-pneumatic tank. Adjusting the pressure switch differential or range would not fix the root cause of the problem.
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