Journal of Korean Institute of Architectural Sustainable Environment and Building Systems ISSN:1976-6483(Print) 2586-0666(Online) 한국건축친환경설비학회논문집

The minimum performance standard of ventilation systems defined in the Rules on Equipment Standards for Buildings, etc. is 0.5 air change per hour. Since this standard is for all households, it can be seen that the doors of all rooms are open, when the doors of the rooms are closed, the appropriate ventilation rates could vary. This inevitably causes differences in air quality for each space depending on the difference in the infiltration rate or the number of occupants for each room. Providing sufficient ventilation rates for all rooms could be the best way for maintaining the indoor air qualities of them. However, as the ventilation rate increases, the fan energy consumption rises as well. Therefore, technologies for saving fan energy with providing the optimal ventilation rate for each room need to be applied for the system. In this study, the room–by-room control system was proposed for saving the ventilation system fan energy. To analyse the actual energy savings with the technology application, the occupancy schedule of residents in a 59 m² apartment house were analysed, and the fan power draws for the cases according to the occupancy schedule were measured in an apartment house with the room-by-room control system application. In addition, to avoid overestimating the ventilation requirement for each room, the infiltration rates measured experimentally with the door closed were considered in the supply air volumes. In these experiments, when room-by-room control was applied, the fan energy savings per day on weekdays were analysed to be about 60% compared to the all-room control. As a future study, we plan to analyze the annual fan energy savings when holiday schedules are combined in various ways, and to check the change in CO₂ concentration for each room through actual field experiments.