Which of the following statements about system pump down is false?

The statement that the liquid receiver service valve must remain in mid position while the compressor is running is false. During a system pump down process, the goal is typically to completely remove refrigerant from the evaporator so that it can be serviced or repaired. This requires that the liquid receiver service valve is closed to contain the refrigerant in the receiver, rather than being left in a mid position which would not effectively isolate the refrigerant from the system.

In contrast, when the compressor is operating, it should be moving refrigerant, and allowing the service valve to remain partially open could lead to a situation where the refrigerant does not fully evacuate from the system, thereby countering the purpose of the pump down process. The other statements correctly describe necessary actions or outcomes in a proper pump down procedure, such as ensuring the suction line is isolated and maintaining the refrigerant within the receiver.