Author : Karthik N 1
Date of Publication :7th June 2016
Abstract: Frost formation on the evaporators reduces its effectiveness hence needs to be melted using external heat source in most of the frost free refrigerator, which contributes to its energy consumption. Currently electrical heaters are used for the defrost purpose. Alternative defrost technology i.e. Hot gas bypass defrost currently used in Industrial refrigeration is tried to be implemented in medium capacitydomestic refrigerator because of its higher Coefficient of Performance and reduced energy consumption. Performance of both electrical heater defrost and hot gas defrost are compared with the help of parameters such as defrost efficiency and heat distribution during defrost. Hot gas defrost has 62.4 % defrost efficiency compared to 38% defrost efficiency of electrical heater.
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