What action does the flush valve perform in loop flush mode when it is deenergized?

In loop flush mode, when the flush valve is deenergized, it functions to open the main flush valve. This process is crucial because it allows for the flushing of the system, facilitating the removal of any contaminants or debris that may have accrued. The opening of the main flush valve allows water to flow through the system, promoting effective cleaning and ensuring that the system maintains optimal performance and efficiency.

In this context, simply closing the main flush valve or main feed line would not serve the intended purpose, as it would impede the flow required for flushing. Similarly, opening the auxiliary flush valve would not achieve the primary goal of the loop flush mode as effectively as opening the main flush valve does. Thus, the correct action that occurs when the flush valve is deenergized in this mode is the opening of the main flush valve.