Abstract: A refrigerant flow metering device for use in a refrigeration system which uses a movable piston with a fixed flow passage in series with a variable area flow passage. The variable flow area is defined by the position of the piston relative to the valve body. The position of the movable piston is a function of refrigerant pressure differential across the piston and the force of a spring member acting in an opposite direction on the piston. In one embodiment, the variable flow area is defined as the clearance between a tapered fixed housing and a tapered portion of the movable piston. In an alternative embodiment, the metering device includes a two-piece piston having a re-open feature that increases the inlet orifice diameter of the piston.