Hitachi RAC-10G5, Service Manual, Page: 52 / 62

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While cooling, the compressor
sometimes stops abruptly.
Q1
Check whether frost sticks on
the heat exchanger of indoor
unit or not.
Wait for 3 – 4 minutes until the
frost melts.
A1
If cooling is performance
when the room temperature
is low, frost may stick on the
heat exchanger of indoor
unit.
Cooling operation
The fan speed does not
change during a dehu-
midifying operation.
Q2
Dehumidifying operation
The fan speed is always LO at
a dehumidifying operation.
A2
Cold air comes out during a
dehumidifying operation.
Q3
To improve the dehumidi-
fication efficiency, LO fan
speed operation is performed.
Therefore the air is cold. This
is not a trouble.
A3
The operation does not stop
even by raising the room
temperature setting of remote
control at a dehumidifying
operation.
Q4
At a dehumidifying operation,
the actual room temperature
is compared with the room
temperature setting when
starting the operation and the
operation is as follows.
1) When actual room tempe-
rature > room temperature
setting.
The operation is according
to the room temperature
setting on the remote
controller.
2) * When actual room tem-
perature < room tempera-
ture setting.
Regardless of the room
temperature setting, the
t e m p e r a t u r e i s a u t o -
matically set slightly lower
than the room temperature.
In this case, the status is as
2) and, therefore, the opera-
tion by the room temperature
control is impossible. Turn off
the On / OFF switch, set the
room temperature to a new
value and turn on the opera-
tion by the On / Off switch.
A4
In the dehumidifying mode,
the temperature set by
remote controller is set
slightly higher than the
room temperature but the
operation starts.
Q5
This is the status in 2) of (A4).
The temperature is set a little
lower than the room temperature
to carry out a dehumidifying
operation as far as possible.
A5
SERVICE CALL Q & A