What must shut off in a pump overfeed system if all compressors shut down?

In a pump overfeed system, the primary function is to circulate liquid refrigerant to evaporators before it is vaporized. If all compressors shut down, it indicates that the refrigeration cycle is no longer operational. Therefore, this situation requires an immediate response to prevent issues such as liquid refrigerant flooding the evaporators or returning to the compressors, which could lead to damage.

Shutting off the liquid feed is vital because, without the compressors running to manage the vaporization of this liquid refrigerant, allowing it to continue feeding into the system could result in excessive liquid accumulation. By halting the liquid feed, the system can prevent potential flooding and ensure that any remaining liquid refrigerant is contained until the compressors are restarted.

Maintaining this control is critical for safety and equipment protection, as the compressors must be operational to handle the liquid effectively. Other aspects, such as the gas feed and refrigeration cycle, are inherently affected by the status of the compressors, making liquid management the priority when they shut down.