Shuttle valve for water softener system and method

A piston assembly for a control valve in a water softener system, the control valve including a drive mechanism, one or more fluid passageways, and a seal assembly arranged within a central bore and in fluid communication with the one or more fluid passageways, the piston assembly comprising:

• a main piston moveably received within the seal assembly and including a first end and a second end opposite to the first end, wherein the drive mechanism is connected to the first end of the main piston to selectively control a position of the main piston;
• a plurality of feet axially extending from the second end of the main piston;
• and
• a shuttle piston moveably received within the seal assembly and axially guided by the plurality of feet, the shuttle piston including a first end and a second end opposite the first end, the first end having a radially inward extending first rib,
• the radially inwardly extending first rib configured to selectively engage the plurality of feet to limit the axial translation of the shuttle piston with respect to the main piston.