Check code
Abnormal points and detection methods
Causes and checkpoints
If overcurrent of DC or the compressor is detected before 30 seconds after
the compressor starts operating.
Closed outdoor stop valve
Decrease of power supply voltage
Looseness, disconnection or reverse phase of
compressor wiring connection
Malfunction of indoor/outdoor fan
Short-cycle of indoor/outdoor unit
Model selection error upon replacement of outdoor
multi controller circuit board
Malfunction of input circuit on outdoor multi controller
circuit board
Defective compressor
Defective outdoor power circuit board
●Diagnosis of defects
Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards.
Diagnosis
Remedy
4210
(UP)
Compressor overcurrent interruption
Chart 1 of 2
Yes
Yes
Yes
No
No
No
57
OCH634C
Is the stop valve (liquid/gas) fully
open?
Is the power supply voltage normal?
Are they set properly?
Open the stop valve (liquid/gas) fully.
Check the power supply facility
(check for power supply open phase).
Set the model selection correctly.
Check the outdoor stop valve.
Check whether the power supply voltage is
normal or not.
Check whether the model selection switch is
set correctly on the outdoor multi controller
circuit board or not.
Turn the power OFF to check for looseness, disconnection
or converse phases of the compressor wiring
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