Troubleshooting
Samsung Electronics
423
4-4-2 Main PCB has no power phenomenon
Outdoor unit display
Main PCB has no power phenomenon (7-seg does not blink)
Judgment Method
Hub PCB power and connection wire to detect.
Cause of problem
∙ HUB PCB connector wire defects and the connection is not.
∙ Main PCB defective.
∙ Hub PCB defective.
∙ High pressure switch operation
1. Cause of problem
Replace Fan PCB
Check the connection status of EMI PCB.
Check the short circuit of EMI PCB Fuse.
Refrigerant overcharge?
High pressure switch is defective.
No
No
Yes
Yes
Yes
HUB PCB CN70 AC220V is connected?
Is a high pressure switch normal?
Check the short circuit of Hub PCB.
Replace Hub PCB
No
Yes
Confirm a blinking of Hub PCB LED.
Connecting the communication wire. (CN96)
No
Yes
Did you check
the connection status of the Main / Hub connection
wire?
Power On
