Combined Convection-Radiation Air Conditioning System using Building Structure combines the advantages of TABS and convection air conditioning. In ordinary TABS, pipes are buried in the frame, but here pipes are laid on the lower (ceiling) surface of the floor slab. Also, jets from a Convection-enhancing Spot fan are sprayed toward the ceiling surface, promoting convection on the frame surface. This airflow promotes timely heat dissipation stored in the frame, and a micro-airflow environment can be formed in the living area. This paper aimed to verify thermal comfort and proper operation. Subjects were given simulated work of low to high metabolic rate, and were asked to report the thermal sensation and comfort in a micro-airflow environment. It was confirmed that comfort could be maintained even at a temperature higher than the general air-conditioning temperature, and an appropriate operating method according to the metabolic rate was elucidated.publishedVersio