Question 76Motor Plants - QMED

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According to the illustrated diesel engine cooling water systems diagram, what is the functional description of the low temperature central fresh water thermostat? Illustration MO-0129

Diagram for USCG Motor Plants QMED: According to the illustrated diesel engine cooling water systems diagram, what...
AThe thermostat is a two-way valve set up to throttle the flow bypassing around the central fresh water cooler.
BThe thermostat is a two-way valve set up to throttle the flow through the central fresh water cooler.
CThe thermostat is a three-way valve set up as a mixer proportioning flow through and around the central fresh water cooler.
DThe thermostat is a three-way valve set up as a diverter proportioning flow through and around the central fresh water cooler.
AI Explanation

The correct answer is C) The thermostat is a three-way valve set up as a mixer proportioning flow through and around the central fresh water cooler. This is the correct answer because the low temperature central fresh water thermostat is designed to mix and proportion the flow of coolant, routing some through the central fresh water cooler and some around it. This allows the thermostat to precisely control the temperature of the coolant entering the engine by mixing hot and cold flows. The other options do not accurately describe the function of this three-way mixing valve thermostat. The other answer choices are incorrect because they either describe a two-way valve that simply throttles flow through or around the cooler, rather than mixing the flows, or they describe a three-way valve acting as a diverter rather than a mixer.

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