When is the self-contained dispenser pump regulating valve functioning properly?

The self-contained dispenser pump regulating valve functions properly when it maintains a specific pressure after the pump has been turned off for a designated amount of time. In this context, the correct answer indicates that the pressure stabilizes at 18 psi one hour after the pump is turned off. This suggests that the regulating valve effectively holds and maintains the pressure within the system, demonstrating its functionality in preventing backflow and ensuring that the system is not losing pressure unnecessarily.

This specific scenario is critical as it assures that any fuel or liquid within the dispenser is retained at the correct pressure, which is vital for safe operation and accurate dispensing when the pump is next engaged. It reflects the ability of the valve to regulate the pressure effectively during the period when the pump is not actively in operation, ensuring that the system remains ready for use without leaks or pressure fluctuations that could lead to operational inefficiencies or safety hazards.