Samsung AM080xXV Series Service Manual page 268

8) 4Way Valve
Inspection item : 4Way Valve of Outdoor Unit.
Error code: None (The resulting report "Undetermined")
Determine the 4Way Valve operation status of the each Outdoor Unit.
If the judgment of 4Way Valve is "Undetermined" : Checking in accordance with the following order.
Auto Trial Operation results,
is Valve and Pressure sensor normal?
Is 4Way Valve connector properly connect?
Is 4Way Valve coil normal?
(Wire breaking, operation impossible, etc.)
Is PCB Output signal normal?
Replace 4Way Valve Body
(Retry the Auto Trial Operation :
If the continuous "Undetermined" is displayed.)
Samsung Electronics
Yes
Yes
Yes
Yes
Complete
No
Check the corresponding Pressure sensor.
No
Confirmation and Measures
No
Replace Valve coil
No
Test Operation
Replace PCB
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