Thermal heterogeneity in indoor environment is not only critical for the thermal comfort with high indoor environment quality, but also contributes to the complexities of ZEB energy saving solutions. There is a growing consensus that variability in indoor conditions can be acceptable to occupants, reduce the energy consumption of buildings without compromising on the thermal comfort perception in occupied spaces. The contribution of this study is to create a novel indoor unit for the zoning air conditioning system and to reveal its thermal heterogeneity in an open-plan office in terms of temperature non-uniformities in the zoning thermal environment. The novel zoning air conditioning system is consisted of multiple supply air openings mounted on zone border separately and one central return air opening. Those supply air (SA) openings, central return air (RA) opening and indoor unit are connected by ducts, the return air is directly conditioned through the central RA and supplied to the border SA openings. Hence in each zone, circulating airflow form from border to the centre, which reduce the air convection between neighbouring zones and improve the thermal efficiency. In this study, the impact of various control strategies on zoning thermal environment are investigated by using computational fluid dynamics (CFD) numerical analysis which are validated through the full-scale field experiments. The CFD simulation prediction result is highly comparable to the experimental findings with an average temperature difference of approximately 0.4K. This research aims to investigate and evaluate the thermal heterogeneity of the novel zoning air conditioning system under varier control strategies. Cases studies under different operating schedules are successful in providing the acceptable temperature difference between neighbouring zones through the CFD numerical analysis. The mechanisms of zoning thermal heterogeneity for circulating airflow application are evaluated, the finding shows that the maximum temperature difference between the neighbouring zone can reach up to 2.8K.