Patent ID: 6389833
Filing Date: 2002-05-21
Classification: F25B,F28D

Abstract:
An evaporator having defrosting capabilities for space-saving and hard-to-reach installations and for connecting to a condensing unit with a condensing coil and a compressor, said evaporator comprising:a) a center tube having a refrigerant inlet for supplying a refrigerant before being evaporated, and conducting the refrigerant in a first direction opposite to said refrigerant inlet of said center tube; b) a middle tube concentrically receiving said center tube and defining a first passage therebetween for conducting a hot injected gas for performing a mild, but positive, defrost of said evaporator as said evaporator continues to operate; and c) an outer tube having a length and an end opposite to said refrigerant inlet of said center tube and concentrically receiving said middle tube and defining a second passage therebetween for conducting the refrigerant after evaporation in a second direction opposite to the first direction and along said length of said outer tube and thereby allowing for heat transfer along said length of said outer tube; wherein said outer tube concentrically receiving said middle tube allows for minimal amount of the refrigerant to be used in the heat transfer.