Description
When pressure at 2 rises above the check spring bias pressure, the seat is pushed away from the piston and flow is allowed from 2 to 1. Reverse flow is locked, unless the pilot pressure at 3 rises above the piston spring bias pressure (adjustable). Any back-pressure at 2 is additive to the pressure setting. Valve design prevents spring going solid and complete unscrewing during adjusting.
¹) At 70% of pressure setting
