Mitsubishi Electric Mr.SLIM PUZ-ZM200YKA Service Manual page 71

Indication
Outdoor controller board
LED1 LED2
(Green) (Red)
3 blinking 1 blinking Abnormality of discharge thermistor/comp.
surface thermistor (TH4/TH33)
Abnormality of superheat due to low
discharge temperature
2 blinking Abnormal high pressure(63H operated)/High
compressor temperature (TRS operated)
3 blinking Abnormality of outdoor fan motor rotational
speed
Protection from overheat operation(TH3)
4 blinking Compressor overcurrent breaking(Startup
locked)
Compressor overcurrent breaking
Abnormality of current sensor (P.B.)
Abnormality of power module
5 blinking Open/short of discharge thermistor (TH4)
and comp. surface thermistor (TH33)
Open/short of outdoor thermistors
(TH3, TH6, TH7 and TH8)
6 blinking Abnormality of heat sink
temperature
7 blinking Abnormality of voltage
4 blinking 1 blinking Abnormality of room temperature thermistor (TH1)
Abnormality of pipe temperature thermistor /
Liquid (TH2)
Abnormality of pipe temperature thermistor/
Condenser-Evaporator
2 blinking Abnormality of drain sensor (DS)
Float switch(FS) connector open
Indoor drain overflow protection
Leakage error (refrigerant system)
3 blinking Freezing (cooling)/overheating
(heating) protection
4 blinking Abnormality of pipe
temperature
5 blinking Indoor unit fan motor error
*1 Check code displayed on remote controller
*2 Refer to the indoor unit's service manual.
OCH738
Check
Contents code
*1
U2
U7
U1
U8
Ud
UF
UP
UH
U6
U3
U4
U5
U9
P1
P2
P9
P4
P5
PA
P6
P8
PB(Pb) Defective fan motor winding
71
Error
Inspection method
1 Check if stop valves are open.
2 Check if connectors (TH4,TH33, LEV-A, LEV-B)
on outdoor controller board are not disconnected.
3 Check if unit is filled with specified amount of
refrigerant.
4 Measure resistance values among terminals on
indoor valve and outdoor linear expansion valve
using a tester.
1 Check if indoor/outdoor units have a short cycle
on their air ducts.
2 Check if connector (63H and TRS) on outdoor
controller board is not disconnected.
3 Check if heat exchanger and filter is not dirty.
4 Measure resistance values among terminals on
linear expansion valve using a tester.
5Check if stop valves are open.
6 C heck if unit is filled with specified amount of
refrigerant.
1 Check the outdoor fan motor.
2 Check if connector (TH3) on outdoor controller
board is disconnected.
1 Check if stop valves are open.
2 Check looseness, disconnection, and converse
connection of compressor wiring.
3 Measure resistance values among terminals on
compressor using a tester.
4 Check if outdoor unit has a short cycle on its air
duct.
1 Check if connectors(TH3,TH4,TH6,TH7
and TH33) on outdoor controller board and
connector (CN3) on outdoor power board are not
disconnected.
2Measure resistance value of outdoor thermistors.
1 Check if indoor/outdoor units have a short cycle
on their air ducts.
2 Measure resistance value of outdoor
thermistor(TH8).
1 Check looseness, disconnection, and converse
connection of compressor wiring.
2 Measure resistance value among terminals on
compressor using a tester.
3 Check if power supply voltage decreases.
4 Check the wiring of CN52C.
1 Check if connectors (CN20, CN21, CN29
and CN44) on indoor controller board are not
disconnected.
2 Measure resistance value of indoor thermistors.
1 Check if connector (CN31)(CN4F) on indoor
controller board is not disconnected.
2 Measure resistance value of indoor thermistors.
3 Measure resistance value among terminals on
drain pump using a tester.
4Check if drain pump works.
5Check drain function.
1Converse connection of piping or wiring
Note: The error will be cancelled by turning off
power, and on again.
2 C heck if there are any inclination or clogging in
drain pipe.
3Check if drain pan or drain sensor is dirty.
4 C heck if any foreign matter is attached to the
moving part of float switch.
5Check LEV for proper function.
1 Check if indoor unit has a short cycle on its air duct.
2 Check if heat exchanger and filter is not dirty.
3 Measure resistance value on indoor and outdoor
fan motors.
4 Check if the inside of refrigerant piping is not
clogged.
1 Check if indoor thermistors(TH2 and TH5) are
not disconnected from holder.
2 Check if stop valve is open.
3Check converse connection of extension pipe.
(on plural units connection)
4 Check if indoor/outdoor connecting wire is
connected correctly.
(on plural units connection)
Detailed
reference
page
P.37
P.38
P.37
P.38
P.40
P.40
P.40
P.40
P.38
P.37
P.38
P.38
P.39
*2
*2
*2
*2
*2
*2
*2
*2