Mitsubishi Electric Mr.Slim PUHZ-P100VKA Service Manual page 38

From the previous page.
Abnormal point and detection method
Check code
Detailed
PFC error (Overvoltage/
codes
Undervoltage/Overcurrent)
• PFC detected any of the fol-
lowing:
a) Increase in DC bus voltage
to 460 V
b) Decrease in PFC control
10
voltage to 12 V DC or lower
c) Increase in input current
(PUHZ-P·VKA only)
U9
(4220)
PFC/IGBT error
(Undervoltage)
• When Compressor is running,
DC bus voltage stays at 310V
or lower for consective 10 sec-
20
onds.
(PUHZ-P·VKA only)
Over heat protection
Abnormal if outdoor pipe thermistor (TH3)
detects 70: or more during compressor
Ud
operation.
(UD)*
(1504)
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 38 A of incurrent is detected
UH
or 34A or more of input current is
(5300)
detected for 10seconds continuously.
Low pressure
Abnormal if the following conditions are
detected for continuously 3 minutes. Note
that it applies when the compressor accu-
mulated operating time is under 30 min-
utes, and 7 minutes has passed after the
compressor operation.
TH33 - TH4 ] 20 : and TH33 > 80 :
UL
(1300)
Thermistors:
TH33: Comp. Surface temperature
TH4: Discharge temperature
TH5: Indoor 2-phase pipe temperature
TH7: Ambient temperature
OCH670
Case
1 Abnormal increase in power
source voltage
2 Decrease in power source
voltage, instantaneous stop.
3 Disconnection of compressor wiring
4 Misconnection of reactor (DCL)
5 Defective outdoor power circuit
board
6 Defective Reactor(DCL)
7 Disconnection or loose
connection 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 outdoor pipe
thermistor (TH3)
3 Defective outdoor controller
board
1 Stop valve is closed.
2 Decrease of power supply
voltage
3 Looseness, disconnection or
converse of compressor wiring
connection
4 Defective compressor
5 Defective outdoor power board
6 Dip switch setting difference of
outdoor controller circuit board.
1 Defective circuit of current
sensor on outdoor power circuit
board
2 Decrease of power supply
voltage
1 Stop valve of outdoor unit is
closed during operation.
2 Leakage or shortage of
refrigerant
3 Malfunction of linear expansion
valve
4 Clogging with foreign objects in
refrigerant circuit
Note:
Clogging occurs in the parts
which become below freezing
point when water enters in
refrigerant circuit.
38
Judgment and action
12 Check the field facility for the power supply.
3 Correct the wiring (U.V.W phase) to
compressor. Refer to "9-9. TEST POINT
DIAGRAM".
4 Correct the wiring of reactor (DCL)
5 Replace outdoor power circuit board.
6 Replace Reactor (DCL).
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.
*The check code in the parenthesis indicates
PAR-30/31MAA model.
1 Open stop valve.
2 Check facility of power supply.
3 Correct the wiring (U V W phase) to
• •
compressor.
Refer to "9-9. TEST POINT DIAGRAM
(Outdoor power circuit board)".
4 Check compressor.
Refer to "9-6. HOW TO CHECK THE PARTS".
5 Replace outdoor power circuit board.
6 Check the DIP switch setting of outdoor con-
troller circuit board.
Refer to "Model Select" section at (1) Function of
switches" in "9-10. FUNCTION OF SWITCHES,
CONNECTORS AND JUMPERS".
1 Replace outdoor power circuit board.
2 Check the facility of power supply.
1 Check stop valve.
2 Check intake superheat.
Check leakage of refrigerant.
Check additional refrigerant.
3 Check linear expansion valve.
Refer to "9-6. HOW TO CHECK THE
PARTS".
4 After recovering refrigerant, remove water
from entire refrigerant circuit under vacuum
more than 1 hour.