When is the solenoid on the 58AF-3 pressure control valve in the type 4 system deenergized?

The solenoid on the 58AF-3 pressure control valve in the type 4 system is deenergized when all pumps are off, which reflects a design principle in water and fuel system management. When no pumps are active, there is obviously no need to maintain pressure in the system, thus the solenoid, which controls the operation of the valve, can be safely deenergized to conserve energy and reduce wear on components.

Deenergizing the solenoid in this situation also ensures that the system can effectively prevent any pressure buildup or water hammer effects that could occur if the valve were to remain energized while no pumps are supplying pressure. This feature contributes to the overall safety and efficiency of the system during periods of inactivity.

In contrast, if any of the other conditions were true, such as a pump being in manual or automatic mode, or even just one pump being off, the system may still require the pressure control valve to maintain certain functions. The design of the 58AF-3 seeks to optimize when the solenoid is energized or deenergized based on the operational status of all pumps, ensuring that it operates only when necessary for efficiency and safety.