Abstract: Embodiments of the invention provide a piston assembly for a control valve in a water softener system. The control valve includes a drive mechanism, one or more fluid passageways, and a seal assembly. The piston assembly includes a main piston moveably received within the seal assembly and including a first end and a second end opposite to the first end, and a shuttle piston moveably received within the seal assembly. The shuttle piston includes a first end and a second end opposite to the first end, and is configured to selectively engage the second end of the main piston to form a seal therebetween and to selectively move relative to the second end of the main piston to form an opening between the second end of the main piston and the first end of the shuttle piston, in response to movement of the main piston.

Abstract: Embodiments of the invention provide a piston assembly for a control valve in a water softener system. The control valve includes a drive mechanism, one or more fluid passageways, and a seal assembly. The piston assembly includes a main piston moveably received within the seal assembly and including a first end and a second end opposite to the first end, and a shuttle piston moveably received within the seal assembly. The shuttle piston includes a first end and a second end opposite to the first end, and is configured to selectively engage the second end of the main piston to form a seal therebetween and to selectively move relative to the second end of the main piston to form an opening between the second end of the main piston and the first end of the shuttle piston, in response to movement of the main piston.

Abstract: Embodiments of the invention provide a piston assembly for a control valve in a water softener system. The control valve includes a drive mechanism, one or more fluid passageways, and a seal assembly. The piston assembly includes a main piston moveably received within the seal assembly and including a first end and a second end opposite to the first end, and a shuttle piston moveably received within the seal assembly. The shuttle piston includes a first end and a second end opposite to the first end, and is configured to selectively engage the second end of the main piston to form a seal therebetween and to selectively move relative to the second end of the main piston to form an opening between the second end of the main piston and the first end of the shuttle piston, in response to movement of the main piston.

Abstract: Embodiments of the invention provide a piston assembly for a control valve in a water softener system. The control valve includes a drive mechanism, one or more fluid passageways, and a seal assembly. The piston assembly includes a main piston moveably received within the seal assembly and including a first end and a second end opposite to the first end, and a shuttle piston moveably received within the seal assembly. The shuttle piston includes a first end and a second end opposite to the first end, and is configured to selectively engage the second end of the main piston to form a seal therebetween and to selectively move relative to the second end of the main piston to form an opening between the second end of the main piston and the first end of the shuttle piston, in response to movement of the main piston.

Abstract: A liquid tank cap incorporates a two-way relief valve in which an annular valve disc has one side sealed against a seal adjacent to its inner diameter and the other side sealed against a seal adjacent to its outside diameter. When subjected to a pressure differential in either direction, the disc deflects so as to increase its concavity and allow air passage by one or the other seal, depending upon whether the pressure in the tank is subatmospheric or superatmospheric.