ALTERNATIVE REFRIGERANTS FOR HCFC 22—A REVIEW

The aim of this paper is to determine the best available alternative which could replace existing refrigerant R22, with minimum or no changes in the air conditioning system. For this purpose, both the theoretical as well as experimental studies done in this area of research have been reviewed. The most popular HFC, R410A is having lower critical temperature, which restricts its usage in compression based systems working at higher condensing temperatures whereas for R407C, a change to synthetic lubricant is required and HC-290 is flammable. It is suggested that until the safety issue of use of hydrocarbon refrigerants in quantities exceeding 500gm is resolved, we should go for those mixtures of HFCs and HCs for which TEWI index is the lowest.