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TROUBLESHOOTING
“RUN” light flickers and “ALARM” is indicated on the remote control switch.
The unit No., alarm code and the unit code is alternately indicated on the set temperature section,
and the unit No. and alarm code are indicated on the display of the outdoor unit PCB.
This alarm code is indicated when voltage between terminal “P” and “N” of transistor module (IPM) is
insufficient and its occurrence is three times in 30 minutes. In the case that the occurrence is smaller
than 2 times, retry is performed.
Alarm
Code
Excessively Low or High Voltage for Inverter (For 5 to 20HP)
*1): If capacitor has high voltage, perform the high voltage discharge work refer to item 1.3.6.
*2): Checking procedures of diode module is indicated in item 1.3.6.
*3): DC voltage measuring position:
IPM “P” Terminal to “+” Terminal of Tester, “N” Terminal to “-” Terminal of Tester
Measuring Position: DC 1000V
Does the voltage
fall during operation
by operation of
other apparatus?
Is connection
correctly between
PCB3 and transistor
module?
Does LED2 on PCB3
ON after compressor's
electromagnetic
switches (CMC)
turn on?
Check capacitors
(CB1, 2).
Restart operation.
Check wiring and
cable capacity.
Connect correctly.
Replace capacitors.
PCB3 is faulty.
Replace it.
Capacitors have high voltage.
Be careful especially. *1)
Yes
Yes
Yes
Check the wiring, diode
module (DM) and
capacitors (CB1, 2). *2)
Normal
Fault
(Loose Wiring,
Change of
Color)
Check Item
Frequency can
increase higher
than 60Hz.
Compressor
stops immediately.
(lower than 30Hz)
Compressor stops
when frequency
increase. (Approx.
30Hz to 60Hz
How is
compressor
operation?
Yes
Is the DC voltage
over 460V?
Yes
* Be careful especially because of high voltage.
Yes
No
No
No
No
No
No
* In case of 380-415V/50Hz, 380V/60Hz:
Is the voltage over 323V during operation?
* In case of 220V/60Hz:
Is the voltage over 170V during operation?
Faulty PCB3 for inverter.
Replace it.
220V/60Hz
460V
230V
380-415V/50Hz
380V/60Hz
Power Supply
Voltage (DC)
* In case of 380-415V/50Hz, 380V/60Hz:
Is the power supply voltage
380V 10% or 415V 10%?
* In case of 220V/60Hz:
Is the power supply voltage 220V 10%?
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