Abstract: A refrigeration unit, particularly adapted for portable refrigerator chests, includes a primary evaporation coil whose inlet end is connected via a capillary tube to a source of pressurized liquid refrigerant. A substantially closed refrigeration receptable in fluid communication with the outlet side of the primary evaporator, receives the refrigerant, which may not have completely evaporated, and separates the phases by venting the evaporated gaseous phase to the atmosphere while directing the unevaporated liquid refrigerant into a second evaporator coil wherein it is completely evaporated. A thermostatically controlled valve regulates the flow of refrigerant to the primary evaporator as a function of the temperature within the chest.