Airwell SX 12 DCI, Service Manual

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TROUBLESHOOTING
12-8
SM YAZ318 1-A.1 GB
12.3.5 Indoor unit diagnostics and corrective actions
No.
Fault
Probable Cause Corrective Action
1-4 Sensor failures
Sensors not connected or
damaged Check sensor connections or
replace sensor
7
Communication
mismatch Indoor and Outdoor controllers
are with different versions
Replace Indoor controller
8 No Communication
Communication or grounding
wiring is not good Check Indoor to Outdoor wiring
and grounding
9 No Encoder Indoor electronics or motor
Check motor wiring, if ok,
replace motor, if still not ok,
replace Indoor controller.
11 Outdoor Unit Fault Outdoor controller problem Switch to Outdoor diagnostics.
17-21 Protections Indication No action
24 EEPROM Not Updated
System is using ROM
parameters and not EEPROM
parameters No action, unless special
parameters are required for unit
operation.
25 Bad EEPROM
No action, unless special
parameters are required for unit
operation.
26 Bad Communication
Communication quality is low
reliability Check Indoor to Outdoor wiring
and grounding
27 Using EEPROM data No problem
28-31 IDU model Indication : DCI-25,35,50,60
12.4 Procedures for checking Main Parts
12.4.1 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).
12.4.2 Checking Main fuse
Check 20A fuse on the Filter Board - If burnt – check the compressor, fan or any other
peripheral that can cause a short. In case of a problematic peripheral - replace it.
In case no problematic peripheral, check the resistance on the DC bank (B+ & B- on the Power
board), if it is less than 30
Ω , replace the controller. Otherwise replace the burnt fuse.
In case of frequent burning fuse, replace the controller.
12.4.3 Checking the Compressor
Check Compressor connections - Repair if needed.
Use a current probe (“Clamp”) to assure that there is an AC current on each phase – no more
than 15A.
In case there is no current, check the resistance between the three poles. Assure the three coil
resistances are almost the same (between 0.8
Ω to 1.5 Ω ).
Change to Stand-by or Power OFF and re-start - If the fault is still “Active” - replace controller.
12.4.4 Checking the Reverse Valve (RV)
The RV has two parts, Solenoid and valve.
Solenoid - Running in heating mode, check the voltage between two pins of reverse valve
connector, normal voltage is 230VAC. if no power supply to RV, Check RV operation with
direct 230VAC power supply, if OK, replace outdoor controller.
Valve - if RV solenoid is OK (as above) but still no heating operation while compressor is On,
replace the valve.