Mitsubishi Electric PUZ-HA30NHA5 Service Manual page 31

Check code
Abnormal point and detection method
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
• Abnormal if current sensor detects −1.5A
to 1.5A during compressor operation. (This
error is ignored in case of test run mode.)
UH
(5300)
Overheat protection
Abnormal if outdoor pipe thermistor (TH3)
detects 158˚F [70:] or more during com-
pressor operation.
Ud
(1504)
Abnormal low pressure (63L worked)
Abnormal if 63L is worked (under −4 PSIG
[−0.03 MPa]) during compressor operation.
63L: Low pressure switch
UL
(1300)
Compressor overcurrent interruption
Abnormal if overcurrent DC bus or com-
pressor is detected after compressor starts
operating for 30 seconds.
UP
(4210)
OCH607
Case
1 Stop valve is closed.
2 Decrease of power supply volt-
age
3 Looseness, disconnection or
converse of compressor wiring
connection
4 Defective compressor
5 Defective outdoor power board
1 Disconnection of compressor
wiring
2 Defective circuit of current sen-
sor on outdoor power circuit
board
1 Defective outdoor fan (fan
motor) or short cycle of out-
door unit during cooling opera-
tion
2 Defective outdoor pipe ther-
mistor (TH3)
1 Stop valve of outdoor unit is
closed during operation.
2 Disconnection or loose con-
nection of connector (63L) on
outdoor controller board
3 Disconnection or loose connec-
tion of 63L
4 Defective outdoor controller
board
5 Leakage or shortage of refriger-
ant
6 Malfunction of linear expansion
valve
1 Stop valve of outdoor unit is
closed.
2 Decrease of power supply volt-
age
3 Looseness, disconnection or
converse of compressor wiring
connection
4 Defective fan of indoor/outdoor
units
5 Short cycle of indoor/outdoor
units
6 Defective input circuit of out-
door controller board
7 Defective compressor
31
Judgment and action
1 Open stop valve.
2 Check facility of power supply.
3 Correct the wiring (U·V·W phase) to compres-
sor.
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.
1 Correct the wiring (U·V·W phase) to compres-
sor. Refer to "10-9. TEST POINT DIAGRAM"
(Outdoor power circuit board).
2 Replace outdoor power 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 stop valve.
2–4 Turn the power off and on again to check
if F3 is displayed on restarting.
If F3 is displayed, follow the F3 process-
ing direction.
5 Correct to proper amount of refrigerant.
6 Check linear expansion valve. Refer to "10-6.
HOW TO CHECK THE PARTS".
1 Open stop valve.
2 Check facility of power supply.
3 Correct the wiring (U·V·W phase) to com-
pressor. Refer to "10-9. TEST POINT
DIAGRAM" (Outdoor power circuit board).
4 Check indoor/outdoor fan.
5 Solve short cycle.
6 Replace outdoor controller circuit board.
7 Check compressor. Refer to "10-6. HOW TO
CHECK THE PARTS".
Note: Before the replacement of the outdoor
controller circuit board, disconnect the
wiring to compressor from the outdoor
power circuit board and check the output
voltage among phases, U, V, W, during
test run. No defect on board if voltage
among phases (U-V, V-W and W-U) is
same. Make sure to perform the voltage
check with same performing frequency.