TY - JOUR TI - Experimental evaluation of internal heat exchanger influence on R-22 window air conditioner retrofitted with R-407C AU - Vijayan Raghavan AU - Srinivasan Pss JN - Thermal Science PY - 2010 VL - 14 IS - 1 SP - 39 EP - 47 PT - Article AB - The performance of one ton of refrigeration window air conditioner working with R-22 and retrofitted with eco friendly alternative refrigerant R-407C is experimentally investigated An internal heat exchanger is also added to the same air conditioner to provide liquid overfeeding operation. When retrofitting the R-22 system with R-407C, the coefficient of performance is found to drop by 7.28%, however when internal heat exchanger is included the performance is improved. It is observed that the inclusion of internal heat exchanger has increased the coefficient of performance by 5.86% when running on R-22 and 6.18% when running on R-407C, under the given conditions.