A method and apparatus for use with a heat exchange system having a compressor, condenser, evaporator, an expansion device, and circulating refrigerant is provided. The apparatus comprises a chamber positioned between the condenser and the evaporator. According to an embodiment of the invention, the chamber comprises a down tube with holes for the passage of refrigerant from the chamber and a top inlet port comprising a vapor expansion screen. The suction of the refrigerant through the holes draws refrigerant towards the top inlet port past the vapor expansion screen, allowing for further cooling within the chamber. When the refrigerant eventually exits the chamber, it is considerably cooler than when it entered the vessel, making the entire refrigeration system more efficient.