In the electrical control circuit of a cooling-only system, the outdoor fan motor ________.

In the electrical control circuit of a cooling-only system, the outdoor fan motor ________.

• A. runs whenever the thermostat calls for heat
• B. runs whenever the compressor is on
• C. runs only when outdoor sensor is high
• D. never runs during cooling mode

Answer: (B)

In cooling, the condenser outdoor unit must reject heat from the refrigerant. The outdoor fan moves ambient air across the condenser coil to remove that heat, enabling the refrigerant to condense properly. Because this heat rejection is required for the cooling cycle, the outdoor fan is wired to run whenever the compressor relay is energized. So when cooling is commanded, the compressor runs and the fan runs at the same time, and both stop when the compressor stops. This is why the best description is that the outdoor fan runs whenever the compressor is on.

In cooling, the condenser outdoor unit must reject heat from the refrigerant. The outdoor fan moves ambient air across the condenser coil to remove that heat, enabling the refrigerant to condense properly. Because this heat rejection is required for the cooling cycle, the outdoor fan is wired to run whenever the compressor relay is energized. So when cooling is commanded, the compressor runs and the fan runs at the same time, and both stop when the compressor stops. This is why the best description is that the outdoor fan runs whenever the compressor is on.