Multi F Four-Way Ceiling Cassette Service Manual

Part 5. Trouble Shooting
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Only for training and service purposes
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26
DC Compressor
Position
• Compressor
Starting fail error
• Check the connection of comp wire “U,V,W”
• Malfunction of compressor
• Check the component of “IPM”, detection parts.
Display
code
Title Cause of error Check point & Normal condition
Is installation
condition normal?
No
Yes
Yes
Recheck power and installation condition
1. Check Pipe clogging/distortion
2. Check Covering (Indoor/Outdoor Unit)
3. Check EEV connector assemble condition/normal
operation
4. Check refrigerant pressure
→ Reassemble or manage if abnormality found
1. Check resistance between each terminal of compressor
(0.438~0.628±7%)
2. Check insulation resistance between compressor
terminal and pipe (over 2MΩ)
→ Replace compressor if abnormality found
Are the resistance
Between each phase and
insulation resistance of Inverter
compressor normal?
No
Yes
1. Check inverter PCB assembly U,V,W connector
connection condition
2. Check wire disconnection and wiring
3. Check compressor terminal connection condition
(bad contact)
→ Reassemble if abnormality found
Is compressor
Wire connection
condition normal?
No
Yes
Check inverter PCB assembly IPM normality
→ Replace inverter PCB assembly
Is inverter PCB assembly normal?
No
U, V, W
GND
<CT Sensing Check Point>
Vdc
WARNING
Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state
of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.
■ Error Diagnosis and Countermeasure Flow Chart