Enhancing performance of an air conditioning system with a two-phase heat recovery loop retrofit

A simulation investigation has been carried out to evaluate the performance enhancement of an existing 5 ton (17.7 kW) air conditioning system with an air-to-air two-phase natural circulation heat recovery loop. The author has developed a simulation program for predicting the performance of two-phase natural circulation heat recovery loops with an air-stream that can condense. The performance of the system is simulated for hot and humid climates which are typical of Southeastern USA. The performance data along, with an economic analysis, has been presented in the paper. This investigation shows that by retrofitting an existing air conditioning system with a two-phase heat recovery loop, the operational cost and the peak demand are reduced. This also results in an increased dehumidification which improves the indoor air quality. A two-phase heat recovery loop will pay for itself in less than a year