Investigation of annual energy performance of a VWV air source heat pump system

This work studies the annual energy performance of a Variable Water Volume (VWV) air source heat pump (ASHP) system by means of experiment and simulation. An advanced R410A ASHP system, integrated with independent normal fan coil unit, small temperature difference fan coil unit and floor radiation heating coil unit indoor terminals, is constructed. Multi-groups of field tests show that system COP varies from 2.0~4.0 for the different operating load under corresponding conditions. Moreover, in order to predict the long term energy performance of the ASHP system, several quasi-steady models are constructed and validated with experimental data. Then the annual energy performances of investigated system are simulated under different climate zones in China. Both experimental and simulation results show that VWV ASHP system can achieve high competitive seasonal energy efficiency for the buildings, which shows the SPF could be more than 3.0. At last, several recommendations based on the simulation results are proposed to the existed heat pump system.