Application of water loop variable refrigerant flow air-conditioning system in large-scale buildings in northern China

A water loop variable refrigerant flow (WLVRF) air-conditioning system is designed to be applied in large-scale buildings in northern China. The system is energy saving and it is an integrated system consisting of a variable refrigerant flow (VRF) air-conditioning unit, a water loop and an air source heat pump. The water loop transports energy among different regions in the buildings instead of refrigerant pipes, decreasing the scale of the VRF air-conditioning unit and improving the performance. Previous models for refrigerants and building loads are cited in this investigation. Mathematical models of major equipment and other elements of the system are established using the lumped parameter method based on the DATAFIT software and the MATLAB software. The performance of the WLVRF system is simulated. The initial investments and the running costs are calculated based on the results of market research. Finally, a contrast is carried out between the WLVRF system and the traditional VRF system. The results show that the WLVRF system has a better working condition and lower running costs than the traditional VRF system.