A study on the distribution characteristics of inflowed warm air is important to analyze warm air storage in a room. Also, in point of energy saving during heating, warm air flow characteristics occurred by circulation and distribution of inflowed warm air should be analyzed, and the storage efficiency should be considered in order to increase efficiency of heating system. For this study, in the real-sized model room, the temperature differences between inflowing warm air and inner room air are 10, 20, $30^{circ}C$(3steps), and the flow rates of inflowing warm air are 0.5, 1, 2, 3m/s(4steps) respectively as dynamic parameters. Also, anemos and vane diffuser are used as inlet geometric condition. Consequently, on geometric conditions, high thermal storage efficiency can be obtained with the vane diffuser, and heat flow characteristics depend on the inflowing velocity more than reference temperature difference.