Ventilator

The air exchange device includes one casing, one air inhaling blower, one air exhausting blower, one heat exchanger, one pressure sensor and one microcomputer. In the casing, the outdoor air and the indoor air flow in separated spaces; the air inhaling blower inside the outdoor air flow space includes air inhaling fan; the air exhausting blower inside the indoor air flow space includes air exhaust fan; the heat exchanger completes the heat exchange between the outdoor air and the indoor air; the pressure sensor is inserted inside pressure measuring hole; and the microcomputer judges whether to have fault in the device based on the measured pressure. The pressure measuring hole is plugged normally and has one pressure sensor inserted in measuring pressure, and the measured pressure is compared with standard value to judge whether to have fault.