Question 468General Subjects - Assistant Engineer

70% to pass

In the illustrated single zone HVAC system, what statement represents the functioning of the diverting relay as it controls the cooling coil flow and the exhaust, outside air and recirculation dampers? Illustration GS-RA-09

Diagram for USCG General Subjects Assistant: In the illustrated single zone HVAC system, what statement represents the...

AThe diverting relay processes the humidistat control signal as long as the space humidity is below the humidistat set point. The diverting relay processes the room thermostat control signal if the space humidity exceeds the humidistat set point.

BThe diverting relay processes the room thermostat control signal as long as the space humidity is below the humidistat set point. The diverting relay processes the room humidistat control signal if the space humidity exceeds the humidistat set point.

CThe diverting relay processes the room thermostat control signal as long as the space temperature is below the thermostat set point. The diverting relay processes the room humidistat control signal if the space temperature exceeds the thermostat set point.

DThe diverting relay processes the humidistat control signal as long as the space temperature is below the thermostat set point. The diverting relay processes the room thermostat control signal if the space temperature exceeds the thermostat set point.

AI Explanation

The correct answer is B. The diverting relay in the HVAC system processes the room thermostat control signal as long as the space humidity is below the humidistat set point. If the space humidity exceeds the humidistat set point, the diverting relay will then process the room humidistat control signal instead. This is because the primary function of the diverting relay is to prioritize temperature control over humidity control. As long as the humidity is within the desired range, the system focuses on maintaining the temperature setpoint. However, if the humidity rises above the setpoint, the diverting relay shifts to control the humidity, overriding the temperature control. The other options are incorrect because they do not accurately describe the prioritization of temperature and humidity control by the diverting relay in this type of HVAC system.

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