Abstract:Operating unit ratio (OUR) was addressed to analyse behavior regulation of variable refrigerant flow (VRF) system. Correspondingly one office building located in Shanghai was investigated to get data of one year including cooling and heating periods. Statistical results showed that maximum value of OUR was about 60% during heating period, the corresponding energy consumption of VRF keeps in line with the increase of OUR and the maximum range value of sample data during statistical intervals was about 0.4. As to the energy consumption in cooling period, it shows exponential variation (ie. flat at beginning and steep in the subsequent) with the increase of OUR, the maximum range value of sample data during statistical intervals was about 0.55. Data envelope analyse (DEA) and Parzen window were used to further investigate the variation characteristics of behavior regulation. Results showed that probability of effective behavior regulation during heating period was about 0.54 and that corresponding value during cooling period was about 0.44.