Valve manifold

A valve assembly, comprising:

• a valve housing including a bore including an upper end, a lower end and an intermediate annular valve seat;
• a low pressure inlet port and a high pressure inlet port;
• a valve member slidably carried by a sealing disk sealing the bore and moveable between a closed position engaging the valve seat and blocking fluid flow through a vertical port and an open position permitting fluid flow through the vertical port, wherein the valve member includes a poppet having a valve stem;
• a piston member having a surface slidably carried in the bore for moving the valve member to the closed position under pressurized conditions, wherein an end of the valve stem is engageable with the surface of the piston member;
• and
• a control for selectively applying pressurized conditions to the piston member for effecting the closed position and reversely conditioned for removing the pressurized conditions and permit movement of the valve member to the open position by pressure conditions in the lower end of the bore, thereby providing two way valve functionality.