| 摘要 |
PROBLEM TO BE SOLVED: To provide a ventilation device capable of effectively performing silent operation even to a model performing 24-hour continuous operation or a model having a so-called cleaning mode.SOLUTION: In such a nighttime or bedtime that output L of an illuminance sensor is a predetermined value Ls or less (step S402: YES), operation in a strong operation mode (step S408) and a cleaning mode (step S409) with relatively large operation sound is prohibited, and only operation in a silent mode (step S410) is allowed.SELECTED DRAWING: Figure 4 |
