Mitsubishi Electric PUZ-WM50VHA Service Manual page 28

Continued from the previous page.
Check code Abnormal points and detection method
PFC error (Overvoltage/
Detailed
Undervoltage/Overcurrent)
codes
• PFC detected any of the fol-
lowing
a) Increase of DC bus voltage
to 430 V. (Without WM50V)
b) Decrease in PFC control
voltage to 12 V DC or lower
c) Increase in input current
(WM50V,WM60V,WM85V,
WM112V only)
10
U9
(4220)
PFC/IGBT error
(Undervoltage)
• When Compressor is running,
DC bus voltage stays at 310 V or
20
lower for consecutive 10 seconds
(WM50V,WM60V,WM85V,
WM112V only)
Overheat protection
Abnormal if TH3, condensing temperature
T detects 70: or more during com-
Ud
63HS
pressor operation.
(1504)
TH3: Thermistor <Liquid>
Abnormal pressure of 63HS
Abnormal if 63HS detects 0.1 MPa or less.
Detection is inoperative for 3 minutes after
compressor starting and 3 minutes after
UE
and during defrosting.
(1509)
63HS: Pressure sensor
Compressor overcurrent interruption
(When compressor locked)
Abnormal if overcurrent of DC bus or
compressor is detected within 30 seconds
UF
after compressor starts operating.
(4100)
Current sensor error or input current error
• Abnormal if current sensor detects –1.0A
to 1.0A during compressor operation.
(This error is ignored in case of test run
mode.)
UH
• Abnormal if 40A (WM50V,WM60V,WM85V,
(5300)
WM112V) of input current is detected or
37A (WM50V,WM60V,WM85V,WM112V)
or more of input current is detected for 10
seconds continuously.
OCH727
Cause
1 Abnormal increase in power
source voltage
2 Decrease in power source
voltage, instantaneous stop
3 Disconnection of compressor
wiring
4 Misconnection of reactor (DCL1-
3:WM60V, WM85V, WM112V
only)(DCL:WM50V only)
5 Defective outdoor power circuit
board
6 Defective reactor (DCL1-
3:WM60V, WM85V, WM112V
only)(DCL:WM50V only)
7 Disconnection or loose con-
nection of CN2 on the outdoor
power circuit board/controller
circuit board
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 Defective outdoor fan (fan
motor) or short cycle of outdoor
unit during cooling operation
2 Defective TH3, condensing
temperature T
63HS
3 Defective outdoor controller board
1 Disconnection or contact failure
of connector (63HS) on the
outdoor controller circuit board
2 Defective pressure sensor
3 Defective outdoor controller cir-
cuit board
1 Decrease of power supply volt-
age
2 Looseness, disconnection or
reverse of compressor wiring
connection
3 Defective compressor
4 Defective outdoor power board
1 Disconnection of compressor
wiring
2 Defective circuit of current
sensor on outdoor power circuit
board
3 Decrease of power supply
voltage
4 Leakage or shortage of
refrigerant
28
judgment and action
12 Check the field facility for the power supply.
3 Correct the wiring (U•V•W phase) to compres-
sor. Refer to "9-6. TEST POINT DIAGRAM".
(Outdoor power circuit board).
4 Correct the wiring of reactor (DCL1-3:WM60V,
WM85V, WM112V only)(DCL:WM50V only)
5 Replace outdoor power circuit board.
6 Replace reactor (DCL1-3:WM60V, WM85V,
WM112V only)(DCL:WM50V only)
7 Check CN2 wiring.
1 Correction of a model select
2 Replace outdoor power circuit board.
3 Replace outdoor controller circuit board.
1 Check outdoor unit air passage.
23 Turn the power off and on again to check
the check code. If U4 is displayed, follow
the U4 processing direction.
1 Check connection of connector (63HS) on the
outdoor controller circuit board.
Check breaking of the lead wire for 63HS.
2 Check pressure by microprocessor.
(Pressure sensor/ 63HS)
(SW2: Refer to "9-7. FUNCTION OF
SWITCHES, CONNECTORS AND
JUMPERS".)
3 Replace outdoor controller board.
1 Check facility of power supply.
2 Correct the wiring (U•V•W phase) to
compressor.
Refer to "9-6.TEST POINT DIAGRAM".
(Outdoor power circuit board).
3 Check compressor.
Refer to "9-4. HOW TO CHECK THE PARTS".
4 Replace outdoor power circuit board.
1 Correct the wiring (U V W phase) to
• •
compressor. Refer to "9-6.TEST POINT
DIAGRAM" (Outdoor power circuit board).
2 Replace outdoor power circuit board.
3 Check the facility of power supply.
4 Check leakage of refrigerant.