[en] Highlights: • Operation guidelines for TABS by considering the building load characteristics were suggested. • Operation guidelines can be used by field technicians other than automatic control system. • Comfort criteria and surface condensation risk during TABS operation were considered in operation guidelines. • The building load characteristics were analyzed through the dynamic energy simulation. • Thermal output from TABS were estimated through the thermal simulation. - Abstract: Since the end of the 1990s, thermally activated building systems (TABSs) have emerged as an energy-efficient and economically viable means of heating and cooling buildings. Because the temperature of the water that these systems use is very close to room temperature, TABSs are one of the most energy- and exergy-efficient types of heating/cooling systems. However, because TABSs have a high thermal inertia and respond only slowly to control inputs, it is very difficult to maintain the room air temperature within a narrow control band. Control methods and operational strategies have been the main concerns of previous studies. There is a limit to the thermal output that a TABS can provide, owing to the possibility of surface condensation forming and possible thermal discomfort of the occupants. Thus, carefully considered operational strategies and use guidelines are necessary when applying such systems. This study focuses on the development of operational guidelines for TABSs according to the heating and cooling load characteristics of a specific campus building. The load characteristics of the building were analyzed, after which load zones were defined according to the heating and cooling characteristics. Simultaneously, the thermal output of a TABS for heating and cooling was calculated with a range of supply water temperatures. Operational guidelines are suggested, classified by load zone