LG AH-W096A0 Service Manual page 68

Trouble Shooting
Display
Title
code
21
DC Peak
Check Flow Chart
Check the wire
connection.(U,V,W)
Is it normal ?
Yes
Check the resistance of
comp. (No difference at
each terminal)
Is it normal ?
Yes
Check the electricity
leakageof the compressor.
(Refer to comp check table)
Is it normal ?
Yes
Check the input power
(Outdoor, Indoor unit)
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Only for training and service purposes
Cause of error
• Instant over current
• Over Rated current
• Poor insulation of IPM
No
Correct
connection
No
Change
Compressor
❊ Dc link voltage table
No
Change
Model
Compressor
1 Phase
3 Phase
- 68 -
Check point & Normal condition
• An instant over current in the U,V,W phase
- Comp lock
- The abnormal connection of U,V,W
• Over load condition
- Overcharging of refrigerant
- Pipe length.
• Poor insulation of compressor
Is it normal ?
(1 Ph : 230V ±10%
3 Ph : 400V ±10% )
Yes
Check DC link
capacitor Is it normal?
(Refer to belows)
Yes
Check Over load condition
- Overcharging of
refrigerant
- Pipe Length
- Condenser is blocked
- Outdoor fan is locked
No
Change Main PCB
Type Non operating
AUUW126C PSC DC300V ¡¾ 10%
AUUW186C PSC DC300V ¡¾ 10%
AUUW246D PFC DC300V ¡¾ 10%
AUUW306D PFC DC300V ¡¾ 10%
AUUW366D PFC DC300V ¡¾ 10%
AUUW426D PFC DC300V ¡¾ 10%
AUUW486D PFC DC300V ¡¾ 10%
AUUW606D PFC DC300V ¡¾ 10%
AUUW368D PSC DC540V ¡¾ 10%
AUUW428D PFC DC540V ¡¾ 10%
AUUW488D PFC DC540V ¡¾ 10%
AUUW608D PFC DC540V ¡¾ 10%
No
Needs electric work
No
Change DC link
capacitor
Or Main PCB
Remove obstruction
Change outdoor fan
or motor
Change refrigerant
DC Link Voltage
Operating
DC280V ¡¾ 10%
DC280V ¡¾ 10%
DC380V ¡¾ 10%
DC380V ¡¾ 10%
DC380V ¡¾ 10%
DC380V ¡¾ 10%
DC380V ¡¾ 10%
DC380V ¡¾ 10%
DC500V ¡¾ 10%
DC680V ¡¾ 10%
DC680V ¡¾ 10%
DC680V ¡¾ 10%
LGE Internal Use Only