PURPOSE: To consider the basic load of the fluctuating concentration of contaminant in indoor air by setting a threshold in the concentration of indoor contaminant as a function and tracking/controlling the threshold in accordance with the inclination of the concentration of indoor contamination.
CONSTITUTION: The concentration K(t) of indoor contamination and the concentration S(t) of outside air contaminant are detected and a ventilation device is operated by depending on at least one switching threshold of the concentration of contaminant. The switching threshold is set as the function of the concentration K(t) of indoor contaminant and the switching threshold is tracked/controlled in accordance with the inclination of the concentration K(t) of indoor contamination. The first switching threshold for closing an outside air introduction part and the second switching threshold for opening the outside air introduction part are installed, and the two switching thresholds are compared with a sensor signal showing the concentration S(t) of contamination in outside air.
GIYUNTAA RIIRU
BERUNTO SHIYUUMAN
