12-5
TROUBLESHOOTING
SM DUO38I 1-A.2 GB
1.3.4 Indoor unit diagnosis by MSMP and corrective actions
No.
Fault
Probable Cause
Corrective Action
1 Sensors failures of all
types
Check sensors connections
or replace sensors.
2 IPM Fault
Electronics HW
problem
Check all wiring and jumper
settings, if OK, replace
electronics.
3 Bad EEPROM
No action, unless special
parameters are required for
unit operation.
4 DC under/over Voltage
Electronics HW
problem
Check outdoor unit power
supply voltage
5 AC under Voltage
Check outdoor unit power
supply voltage
6 Indoor / Outdoor unit
Communication mismatch
Indoor and Outdoor
controllers are with
different versions
Replace Indoor controller
7 No Communication
Communication or
grounding wiring is not
good.
Check Indoor to Outdoor
wiring and grounding
8 Compressor Lock
Switch unit to STBY and
restart
9 Bad Communication
Communication quality is
low reliability
Check Indoor to Outdoor
wiring and grounding
1.4 Judgment by MegaTool
MegaTool is a special tool to monitor the system states.
Using MegaTool requires:
x
A computer with RS232C port.
x
A connection wire for MegaTool.
x
A special MegaTool software.
Use MegaTool according to following procedure:
x
Setup MegaTool software: copy the software to the computer.
x
Connect RS232C port in computer with MegaTool port in Indoor/Outdoor unit controller by
the connection wire.
x
Run the software and choose the COM port, you can monitor the A/C system state in monitor
tab.
1.5 Simple procedures for checking the Main Parts
1.5.1 Checking Mains Voltage.
Confirm that the Mains voltage is between 198 and 264 VAC. If Mains voltage is out of this range,
abnormal operation of the system is expected. If in range check the Power (Circuit) Breaker and
look for broken or loosed cable lugs or wiring mistake(s).
1.5.2 Checking Power Input.
If Indoor unit power LED is unlighted, power down the system and check the fuse of the Indoor unit. If the fuse
is OK replace the Indoor unit controller. If the fuse has blown, replace the fuse and power up again.
Checking Power Input procedure for the Outdoor unit is the same as with the Indoor unit.
