| It is found that there exist some problems in the installations testing refrigeration performance of chiller for air conditioning used in the experiment of single-stage compression refrigeration cycle. They are listed as following: (1) lower evaporation temperature and higher discharge temperature may cause coefficient of performance drops, for refrigerant system and water system does not match; (2) electric power is wasted to supply cooling load to refrigeration system using electric heater while large quantity of latent heat from condenser is not recycled; (3) only tap water is added to make the cooling water cooler, which leads to waste of water. To solve these problems, some measurements were put forward to better the testing system and an energy-saving chiller system was designed for experiment use.Firstly, refrigeration system and water system equipment were selected again based on thermodynamic calculation to make refrigerant system match with water system. Secondly, inlet water temperature of the evaporator was controlled by pouring proper amount of cooling water into chilled water tank to provide enough cooling load to the evaporator. Then the electric heater is removed from the chilled water tank. Thus, energy consumption became less. Thirdly joint chilled water tank with cooling water tank and make the water surface in chilled water tank higher than that in the cooling water tank. Then, when cooling water enters the chilled water tank, extra chilled water may overflow into the cooling water tank. Thus, the condenser heat rejection can be recycled. Fourthly, combined water tank was buried under ground and heat can be transferred to the soil from cooling water. Thus its temperature can drop to around 25℃ and no tap water is added any more. In additional, exergy analysis was also conducted on the newly designed energy saving refrigeration system for air conditioning use. It is pointed out that there still exist rooms to better the system performance.
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