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FILE NO. SVM-05003
9-2-2. Incorrect cable connection between Indoor
and outdoor units
The indoor unit is connected to the outdoor unit with
5 cables (Heat pump model) or 3 cables (Cooling Only
model). Check that the indoor and outdoor units have
been properly connected with terminals assigned the
same numbers. If the connectors are not properly
connected, the outdoor unit will not operate normally,
or OPERATION lamp and TIMER lamp will blink (5Hz).
9-2-3. Program control
The microcontroller operates as shown in Table 9-2-1
to control the air conditioner. If there are any opera-
tional problems, check whether or not the problems
correspond to Table 9-2-1. If they correspond to the
Table, they are not problems with the air conditioner,
but they are indispensable operations to control and
maintain the air conditioner properly.
9. TROUBLESHOOTING CHART
9-1. Troubleshooting Procedure
If there is no trouble corresponding to 9-2, check
whether or not there are faulty parts following
9-4. Self-Diagnosis by Remote Control.
9-2. Basic Check Items
9-2-1. Power supply voltage
The line voltage must be AC 220
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240V. If it is not
within this range, the air conditioner may not operate
normally.
Table 9-2-1
1
When the main power supply is turned on,
the OPERATION lamp on the indoor unit
blinks.
2
The indoor fan motor speed does not change
in the Dry operation.
3
The compressor is not turned off even though
the room temperature is in the range that the
compressor is turned off.
4
The compressor is not turned on and off even
though the thermo control is operated in the
Dry operation.
5
The PRE-DEF. lamp is indicated when the
Heating operation starts.
6
The outdoor fan motor stops in the Heating
operation.
7
The compressor is not turned on even though
the room temperature is in the range that the
compressor is turned on.
8
The operation mode changes in the
Automatic operation.
No.
Operation of air conditioner
Descriptions
The OPERATION lamp blinks to indicate that power is turned on.
If the [START/STOP] button is pressed, the lamp stops blinking.
The indoor fan motor speed is automatically controlled in the Dry
operation.
The compressor has a function that it is not turned off for
3 minutes after it is turned on even though the room temperature
is in the range that the compressor is turned off.
In the Dry operation, the compressor is turned on and off
automatically at the regular intervals, independent of the thermo
control.
The PRE-DEF. lamp is indicated during the Defrosting
operation or if the indoor heat exchanger temperature is low when
the Heating operation starts. At this time, the indoor fan motor
stops to prevent cold air from blowing in the room.
When the indoor heat exchanger temperature is high, the outdoor
fan motor is stopped by the high-temperature limit control
operation.
The compressor is not turned on in the restart delay timer
(3-minutes timer) operation. It is also not turned on after the power
supply is turned on because of this timer operation.
In Automatic operation, the room temperature is detected all time
for control fan speed and the operation mode is changed every
15 minutes according to difference between the room temperature
and the preset temperature.
Follow the details of
9-2. Basic Check Items.