| 摘要 |
PROBLEM TO BE SOLVED: To prevent a room to be adjusted from being changed into a negative pressure state when an air supply and exhaust operation is started.SOLUTION: This invention provides control means 18 that is operated in such a way that when a starting instruction for air supply and exhaust operation is accepted, an air supply fan Fs is energized prior to opening of air supply opening or closing dampers D1, Ds, Dss and exhaust opening or closing dampers D2, Dr, Drr, thereafter when detected pressures of pressure sensors 14, 11 for detecting pressures (ps) in air supply passages 3, 3a or pressure (pa) in an object room 5 to be adjusted is increased up to a set safety pressure higher than atmospheric pressure or when an elapsing time ranging from an air supply fan starting operation counted by a timer reaches to a set safety time,the air supply opening or closing dampers D1, Ds, Dss and the exhaust opening or closing dampers D2, Dr, Drr are opened. |
