Service Call Q & A - Hitachi RAS-07GH4 Service Manual

SERVICE CALL Q & A
Cooling operation
While cooling,
Q1
compressor sometimes stops
abruptly.
Dehumidifying operation
The fan speed does not
Q2
change during
dehumidifying operation.
Cold air comes out during a
Q3
dehumidifying operation.
The operation does not stop
Q4
even by raising the room
temperature setting of remote
control at a dehumidifying
operation.
In the dehumidifying mode,
Q5
the temperature set by
remote controller is set
slightly higher than the room
temperature
operation starts.
the
a
but the
Check whether frost sticks
A1
on the heat exchanger of in-
door unit or not.
Wait for 3 – 4 minutes until
the frost melts.
The fan speed is always LO
A2
at a dehumidifying operation.
To improve the dehumidi-
A3
fication efficiency, LO fan
speed operation
performed. Therefore the air
is cold. This is not a trouble.
At a dehumidifying operation,
A4
the actual room temperature is
compared with the room tem-
perature setting when starting
the operation and the opera-
tion is as follows.
1) When actual room tem-
perature > room tempera-
ture setting.
The operation is according
to the room temperature
setting on the remote con-
troller.
2) * When actual room tem-
perature < room tempera-
ture setting
Regardless of the room
temperature setting, the
temperature is automati-
cally set slightly lower than
the room temperature.
In this case, the status is as 2)
and, therefore, the operation
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.
This is the status in 2) of
A5
(A4). The temperature is set
a little lower than the room
temperature to carry out a
dehumidifying operation as
far as possible.
– 54 –
If cooling is performance
when the room temperature
is low, frost may stick on the
heat exchanger of indoor
unit.
is