A diaphragm sealed, pressure balanced valve assembly (10, 120, 160, 200, 254) comprising: a valve body; and a cartridge (14, 121) connected to the valve body, the cartridge including: a cartridge loading end; a retaining member engaged to the cartridge loading end; and a valve member (60, 126, 202) sliding coaxial to a longitudinal axis of the valve body, wherein the valve member (60, 126, 202) includes a piston end slidably received in a cylinder cavity of the retaining member and an armature portion (62, 164) oppositely oriented with respect to the piston end; and a resilient material diaphragm (82, 212) connected to and extending diametrically outward from the valve member (60, 126, 202) having a diaphragm body clasped between the retaining member and the cartridge loading end creating a fluid pressure boundary, characterized in that the diaphragm body is configured such that when the armature portion (62, 164) of the valve member (60, 126, 202) is slidably moved coaxially to the longitudinal axis of the valve body to a valve open position by energizing a coil, a biasing force is created by the diaphragm (82, 212) when the diaphragm body elastically deflects between a valve closed position and the valve open position, the biasing force subsequently assisting sliding movement of the valve member (60, 126, 202) thereby decreasing a valve closing time to reach the valve closed position when the coil is de-energized. a valve body; and a cartridge (14, 121) connected to the valve body, the cartridge including: a cartridge loading end; a retaining member engaged to the cartridge loading end; and a valve member (60, 126, 202) sliding coaxial to a longitudinal axis of the valve body, wherein the valve member (60, 126, 202) includes a piston end slidably received in a cylinder cavity of the retaining member and an armature portion (62, 164) oppositely oriented with respect to the piston end; and a resilient material diaphragm (82, 212) connected to and extending diametrically outward from the valve member (60, 126, 202) having a diaphragm body clasped between the retaining member and the cartridge loading end creating a fluid pressure boundary, a cartridge loading end; a retaining member engaged to the cartridge loading end; and a valve member (60, 126, 202) sliding coaxial to a longitudinal axis of the valve body, wherein the valve member (60, 126, 202) includes a piston end slidably received in a cylinder cavity of the retaining member and an armature portion (62, 164) oppositely oriented with respect to the piston end; and a resilient material diaphragm (82, 212) connected to and extending diametrically outward from the valve member (60, 126, 202) having a diaphragm body clasped between the retaining member and the cartridge loading end creating a fluid pressure boundary, characterized in that the diaphragm body is configured such that when the armature portion (62, 164) of the valve member (60, 126, 202) is slidably moved coaxially to the longitudinal axis of the valve body to a valve open position by energizing a coil, a biasing force is created by the diaphragm (82, 212) when the diaphragm body elastically deflects between a valve closed position and the valve open position, the biasing force subsequently assisting sliding movement of the valve member (60, 126, 202) thereby decreasing a valve closing time to reach the valve closed position when the coil is de-energized.