Question 183Electricity/Electronics - 1st Asst/Chief70% 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 C.
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. As water absorbs air over time, the air cushion in the tank becomes depleted, causing the pressure switch to cycle on and off rapidly (short cycling) in response to the unusually high water level.
The other options are incorrect because:
A) Bleeding off air from the tank would not address the root cause of the air absorption issue.
B) Adjusting the pressure switch differential would not fix the underlying problem of the air cushion depletion.
D) Raising the pressure switch range would not resolve the short cycling issue caused by the insufficient air cushion.
Related Questions
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