Study of retrofit for refrigeration and air-conditioning steam compression systems

Resumo

This study shows how to replace refrigerant fluids, such as R-12, to newer fluids (MP39, produced by DuPont; ISCEON49, by Rhodia; and R134a). The performances of studied refrigeration systems after retrofit must having, at least, about the same results if compared with these systems before retrofit. For MP39 and ISCEON49, the exchange of equipments aren’t necessary, contrary to R134a, where compressor and dryer must being substituted. Afterwards, a vacuum extraction of R-12 is transferred to a special equipment, being this fluid stored to other purposes. An evacuation is carried out to avoid moisture in the system to apply the desired fluid. The new refrigerants have presented a higher theoretical COP (seen in this study as COPF) and real COP, if compared with R12 (in this case, the COPF of R134a is slightly smaller than COPF of R12), even with flows decreased. More heat is exchanged through evaporator, and more power is used through the use of MP39. These values are diminished with the use of ISCEON49 and R-12 respectively.