Mitsubishi Electric PUZ-WZ50VAA Service Manual page 37

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 WZ50V)
b) Decrease in PFC control
voltage to 12 V DC or lower
c) Increase in input current
(WZ50V,WZ60V,WZ80V)
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
(WZ50V,WZ60V,WZ80V)
Overheat protection
Abnormal if TH3, condensing temperature
T detects 70
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
after compressor starts operating.
UF
(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 (WZ50V,WZ60V,WZ80V)
(5300)
of input current is detected or 37A
(WZ50V,WZ60V,WZ80V) or more of
input current is detected for 10 seconds
continuously.
OCH816
Incorrect switch settings on the
outdoor controller circuit board
for model select
Defective outdoor power circuit
board
Defective outdoor controller
circuit board
°C
or more during com-
Cause
Abnormal increase in power
source voltage
Decrease in power source
voltage, instantaneous stop
Disconnection of compressor
wiring
Misconnection of reactor
Defective outdoor power circuit
board
Defective reactor
Disconnection or loose con-
nection of CN2 on the outdoor
power circuit board/controller
circuit board
Defective outdoor fan (fan
motor) or short cycle of outdoor
unit during cooling operation
Defective TH3, condensing
temperature T
63HS
Defective outdoor controller board
Disconnection or contact failure
of connector (63HS) on the
outdoor controller circuit board
Defective pressure sensor
Defective outdoor controller cir-
cuit board
Decrease of power supply volt-
age
Looseness, disconnection or
converse of compressor wiring
connection
Defective compressor
Defective outdoor power board
DIP switch setting difference of
outdoor controller circuit board
Disconnection of compressor
wiring
Defective circuit of current
sensor on outdoor power circuit
board
Decrease of power supply
voltage
Leakage or shortage of
refrigerant
37
judgment and action
Check the field facility for the power supply.
Correct the wiring (U•V•W phase) to compres-
sor. Refer to "9-6. TEST POINT DIAGRAM".
(Outdoor power circuit board).
Correct the wiring of reactor
Replace outdoor power circuit board.
Replace reactor
Check CN2 wiring.
Correction of a model select
Replace outdoor power circuit board.
Replace outdoor controller circuit board.
Check outdoor unit air passage.
Turn the power off and on again to check
the check code. If U4 is displayed, follow
the U4 processing direction.
Check connection of connector (63HS) on the
outdoor controller circuit board.
Check breaking of the lead wire for 63HS.
Check pressure by microprocessor.
(Pressure sensor/ 63HS)
(SW2: Refer to "9-7. FUNCTION OF
SWITCHES, CONNECTORS AND
JUMPERS".)
Replace outdoor controller board.
Check facility of supply.
Correct the wiring (U•V•W phase) to compres-
sor.
Refer to "9-6.TEST POINT DIAGRAM".
(Outdoor power circuit board).
Check compressor. Refer to "9-4. HOW TO
CHECK THE PARTS".
Replace outdoor power circuit board.
Check the DIP switch setting of outdoor
controller circuit board.
Correct the wiring (U V W phase) to
• •
compressor. Refer to "9-6.TEST POINT
DIAGRAM" (Outdoor power circuit board).
Replace outdoor power circuit board.
Check the facility of power supply.
Check leakage of refrigerant.