41
Check Code
Abnormal points and detection method
Case
Judgment and action
U9
(4220)
Detailed
codes
PFC error (Overvoltage/
Undervoltage/Overcurrent)
• PFC detected any of the fol
-
lowing:
a) Increase of DC bus voltage
to 420 V.
b) Decrease in PFC control
voltage to 12 V DC or lower.
c) Increase in input current
to 50 A peak. (For models
equipped with single-phase
PFC only)
Not applicable for ZM100–140 model.
Check the switch setting for Model Select
on the outdoor controller circuit board.
10
20
PFC/IGBT error
(Undervoltage)
• When Compressor is running,
DC bus voltage stays at 310V
or lower for consecutive 10
seconds
(ZM100–140V)
1
Incorrect switch settings on the
outdoor controller circuit board for
model select
2
Defective outdoor power circuit board
3
Defective outdoor controller circuit
board
1
Correction of a model select
2
Replace outdoor power circuit board.
3
Replace outdoor controller circuit board
Ud
(UD)*
(1504)
Over heat protection
Abnormal if outdoor pipe thermistor (TH3)
detects 70
:
or more during compressor
operation.
1
Defective outdoor fan (fan motor)
or short cycle of outdoor unit during
cooling operation
2
Defective outdoor pipe thermistor
(TH3)
3
Defective outdoor controller board
1
Check outdoor unit air passage.
23
Turn the power off and on again to
check the check code. If U4 is dis-
played, follow the U4 processing direc-
tion.
*The check code in the parenthesis indi-
cates PAR-3xMAA ("x" represents 0 or
later).
UF
(4100)
Compressor overcurrent interruption
(When compressor locked)
Abnormal if overcurrent of DC bus or
compressor is detected within 30 seconds
after compressor starts operating.
1
Stop valve is closed.
2
Decrease of power supply voltage
3
Looseness, disconnection or con-
verse of compressor wiring connec-
tion
4
Defective compressor
5
Defective outdoor power board
6
DIP switch setting difference of out-
door controller circuit board.
1
Open stop valve.
2
Check facility of power supply.
3
Correct the wiring (U
•
V
•
W phase) to
compressor. Refer to "10-9. TEST
POINT DIAGRAM" (Outdoor power
circuit board).
4
Check compressor.
Refer to "10-6. HOW TO CHECK THE
PARTS".
5
Replace outdoor power circuit board.
6
Check the DIP switch setting of outdoor
controller circuit board. Refer to "Model
Select" in "1) Function of switches" in
"10-10. FUNCTION OF SWITCHES,
CONNECTORS AND JUMPERS".
UH
(5300)
Current sensor error or input current error
•
Abnormal of 38 A of input current is
detected, or 34 A or more of input current
is detected for 10 seconds continuously
(ZM100–140V only)
1
Disconnection of compressor wiring
2
Defective circuit of current sensor on
outdoor power circuit board
3
Decrease of power supply voltage
1
Correct the wiring (U
•
V
•
W phase) to
compressor. Refer to "10-9. TEST
POINT DIAGRAM" (Outdoor power
circuit board).
2
Replace outdoor power circuit board.
3
Check the facility of power supply.
OCH654
