Question 56General Subjects - QMED

70% to pass

Which of the valves listed for the device shown in illustration will be open while the unit is operating in the back flush mode? Illustration GS-0153

Diagram for USCG General Subjects QMED: Which of the valves listed for the device shown in illustration will be open...
Avalve "4"
Bvalves "4" and "5"
Cvalves "4" and "14"
Dvalves "4", "5", and "14"
AI Explanation

The correct answer is C) valves "4" and "14". When operating in the back flush mode, valves 4 and 14 need to be open to allow water to flow through the system in the reverse direction for cleaning purposes. Valve 4 allows water to enter the system, while valve 14 provides the exit path for the back flushing flow. The other answer choices are incorrect because valve 5 would typically be closed during back flushing, and having all three valves 4, 5, and 14 open is not the correct configuration for the back flush mode of operation.

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