Airwell SX 12 DCI, Service Manual

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TROUBLESHOOTING
12-4
SM YAZ318 1-A.1 GB
12.3.2 Outdoor unit diagnostics and corrective actions
No Fault Name Fault Description Corrective Action
1 OCT bad
2 CTT bad
3 HST bad
4 OAT bad
5 OMT bad
6 RGT bad
7 RLT bad
Thermistor not connected or
damaged
Check Thermistor (12.4.6)
8 Reserved NA NA
9 Reserved NA NA
10 Reserved NA NA
11 Compressor IPM Fault /
IPM Driver Pin /
Compressor Current
Sensor Fault
PM module detect shoot-through
current / IPM driver control pin is
unconditionally latch to high state /
The quiescent reference voltage of
sensor resistor is either too high or
too low. Disconnect the compressor plug and
measure between U-V, U-W for
resistance using multimeter.
Resistance value should be below 1
OHM. If multimeter display high
resistance, replace compressor.
Make sure the phase sequence of U-
V-W is correctly plug into the
compressor, othewise replace
controller if error is persistent
12 Bad EEPROM Writing to EEPROM is impossible
or EEPROM IC is damage There is no electrinonic corrective
action, just replace controller if error
is persistent.
Note: A/C still be able to operate, but
no event logging and mode restore
on power up
13 DC under voltage The capacitor bank DC voltage
supply for the compressor is below
operable value Check AC input line voltage RMS
value, it should read above 198VAC.
If voltage is above 198VAC, and DC
under voltage error is continuous
display, replace controller.
14 DC over voltage The capacitor bank DC voltage
supply for the compressor is too
high value Check AC input line voltage RMS
value, it should read below 264VAC.
If voltage is below 264VAC, and DC
over voltage error is continuously
display, replace controller.
15 AC under voltage/AC
over Voltage/Zero
Crossing detection
The AC input supply voltage is
below the limit of 198V / The AC
input supply voltage is above 264V
/ The AC line frequency is out of
range from 45Hz to 55Hz. Check AC input line voltage RMS
value, it should read in the range of
198VAC – 264VAC. Check AC input
line operating frequency, it should be
in the range from 45Hz to 55Hz. If
error is continuously being display,
replace controller.
16 Mismatch between IDU
& ODU models
Miss-match between the IDUs
connected to port A,B,C or D, or
the total capacity code of IDUs is
higher than the ODU maximum
capacity code Change configuration if needed.
17 No Communication No signals in lineA,B,C,D Check communication (12.4.7)
18 System Over Power Compressor stopped due to over
power protection No action required
19 PFC Current sensor Controller cannot detect valid AC
line current after compressor start If error is continuously being display,
replace controller.