Friedrich MD24Y3J Svc Manual page 65

Display
Title
code
DC Compressor
26
Position
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.
n Error Diagnosis and Countermeasure Flow Chart
Is installation
condition normal?
Yes
Are the resistance
Between each phase and
insulation resistance of Inverter
compressor normal?
Yes
Is compressor
Wire connection
condition normal?
Yes
Is inverter PCB assembly normal?
Yes
Recheck power and installation condition
* AUUW24GD2 [MR24UY3J]
Only for training and service purposes
Cause of error
• Compressor
Starting fail error
1. Check Pipe clogging/distortion
2. Check Covering (Indoor/Outdoor Unit)
3. Check EEV connector assemble condition/normal
No
operation
4. Check refrigerant pressure
→ Reassemble or manage if abnormality found
1. Check resistance between each terminal of compressor
2. Check insulation resistance between compressor
No
terminal and pipe
→ Replace compressor if abnormality found
1. Check inverter PCB assembly U,V,W connector
connection condition
2. Check wire disconnection and wiring
No
3. Check compressor terminal connection condition
(bad contact)
→ Reassemble if abnormality found
Check inverter PCB assembly IPM normality
No
→ Replace inverter PCB assembly
U, V, W
<CT Sensing Check Point>
- 65 -
Check point & Normal condition
• Check the connection of comp wire "U,V,W"
• Malfunction of compressor
• Check the component of "IPM", detection parts.
GND
Vdc