Hitachi RAC-70YH7, Service Manual

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1. In quiet or stop operation, slight flowing noise of refrigerant in the refrigerating cycle is heard occasionally,
but this noise is not abnormal for the operation.
2. When it thunders near by, it is recommended to stop the operation and to disconnect the power cord plug
from the power outlet for safety.
3. In the event of power failure, the airconditioner will restart automatically in the previously selected mode
once the power is restored. In the event of power failure during TIMER operation, the timer will be reset
and the unit will begin or stop operating under a new timer setting.
4. If the room air conditioner is stopped by adjusting thermostat, or missoperation, and re-start in a moment,
there is occasion that the cooling and heating operation does not start for 3 minutes, it is not abnormal
and this is the result of the operation of IC delay circuit. This IC delay circuit ensures that there is no
danger of blowing fuse or damaging parts even if operation is restarted accidentally.
5. This room air conditioner should not be used at the cooling operation when the outside temperature is
below –10
°
C (14
°
F).
6. This room air conditioner (the reverse cycle) should not be used when the outside temperature is below
–15
°
C (5
°
F).
If the reverse cycle is used under this condition, the outside heat exchanger is frosted and efficiency falls.
7. When the outside heat exchanger is frosted, the frost is melted by operating the hot gas system, it is not
trouble that at this time fan stops and the vapour may rise from the outside heat exchanger.
CAUTION