Mitsubishi Electric PUHZ-W50VHA Service Manual page 58

Check Code Abnormal point and detection method
Abnormal power synchronous
Detailed
codes
signal
• No input of power
synchronous signal to power
circuit board
• Power synchronous signal
of 44 Hz or less, or 65 Hz or
more is detected on power
circuit board.
08
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
10
c) Increase in input current to
U9
50A peak
(W50V only)
PFC/IGBT error
(Undervoltage)
• When Compressor is running,
DC bus voltage stays at 310
V or lower for consecutive 10
seconds
(W50–85V/HW140V only)
20
Overheat protection
Abnormal if outdoor pipe thermistor (TH3)
detects 70: or more or condensing
temperature of pressure sensor (63HS)
detects 70: or more during compressor
operation.
Ud
Compressor overcurrent interruption
(When compressor locked)
Abnormal if overcurrent of DC bus or
compressor is detected within 30 seconds
after compressor starts operating.
UF
OCH439M
Cause
1 Distortion of power source
voltage, noise superimposition
2 Disconnection or loose con-
nection of earth wiring
3 Disconnection or loose con-
nection of CN2 on the outdoor
power circuit board/controller
circuit board
4 Defective power synchronous
signal circuit in outdoor con-
troller circuit board
5 Defective power synchronous
signal circuit in outdoor power
circuit board
1 Abnormal increase in power
source voltage
2 Decrease in power source
voltage, instantaneous stop
3 Disconnection of compressor
wiring
4 Misconnection of reactor (ACL)
5 Defective outdoor power circuit
board
6 Defective reactor (ACL)
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 Disconnection or loose con-
nection of CNAF on the out-
door power circuit board/ACT
module (W85V)
3 Defective ACT module (W85V)
4 Disconnection or loose con-
nection of CN2 on the outdoor
power circuit board/controller
circuit board
5 Defective outdoor power cir-
cuit board
6 Defective outdoor controller
circuit board
1 Defective outdoor fan (fan
motor) or short cycle of out-
door unit during cooling opera-
tion
2 Defective outdoor pipe
thermistor (TH3)
3 Defective outdoor controller
board
4 Defective pressure sensor
1 Decrease of power supply
voltage
2 Looseness, disconnection or
reverse of compressor wiring
connection
3 Defective compressor
4 Defective outdoor power board
5 Decreased water flow
6 Clogged filter of water pipe
7 Clogged plate heat exchanger
8 Locked water pump
9 Malfunction of water pump
58
Judgment and action
1 Check the field facility for the power supply.
2 Check earth wiring.
3 Check CN2 wiring.
4 Replace outdoor controller circuit board.
5 Replace outdoor power circuit board.
12 Check the field facility for the power supply.
3 Correct the wiring (U·V·W phase) to com-
pressor.
4 Correct the wiring of reactor (ACL).
5 Replace outdoor power circuit board.
6 Replace reactor (ACL).
7 Check CN2 wiring.
1 Correction of a model select
2 Check CNAF wiring.
3 Replace ACT module.
4 Check CN2 wiring.
5 Replace outdoor power circuit board.
6 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.
4 Check pressure by microprocessor.
(Pressure sensor/ 63HS)
(SW2: Refer to "9-7. OUTDOOR UNIT
OPERATION MONITOR FUNCTION".)
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
CHECK THE PARTS"
4 Replace outdoor power circuit board.
–
9 Check water circuit and repair the defect.
5
"9-4. HOW TO