FIELD PERFORMANCE MEASUREMENTS OF A VRV AC/HP SYSTEM

The performance potential of a variable refrigerant volume (VRV) air conditioning and heat pump system was investigated experimentally during field tests and compared to the performance of the existing variable air volume (VAV) cooling system. Two different control modes; individual control and master control are applied to the VRV system. The master control using only one thermostat at the same location as that of the original VAV system is intended to simulate the existing system’s control mode, thus the effects of the control modes on energy consumption and thermal comfort can be evaluated. It is found that cooling performance factor (CPF) of the VRV system in the individual control mode is from 3 to 15% higher than that of the VRV system in master control mode. Similar to the VAV system, the VRV system in master control mode is not sufficient to provide thermal comfort for multiple rooms. Whereas, the VRV system in individual control mode provides the desired set temperature and the corresponding comfort level throughout the season.