In this research we will propose an operational method for improving the efficiency of water-cooled packaged air conditioning systems. Water-cooled packaged air conditioners are installed at large-scale communication facilities and data centers. In the past, efforts were made to improve the efficiency of air-cooled packaged air conditioners using technologies that operated the air conditioners in low compression ration regions. By applying these technologies to water-cooled packaged air conditioners, we have succeeded in improving the efficiency of the refrigeration cycle. It is still necessary, however, to reduce the power consumption of the cooling tower and cooling pump in order to improve the efficiency of the air conditioning system as a whole. In this paper, we conducted system simulations, and calculated efficiency over one year. Based on the results of these simulations, we expect to be able to improve efficiency by about 10% at 30% partial load by minimizing the repetition of start/stop operations in the cooling tower.
