Mitsubishi Electric PUZ-ZM200YKA2-ET Service Manual page 79

Indication
Outdoor controller
board
LED1 (Green) LED2 (Red)
3 blinking 1 blinking Abnormality of comp. surface
thermistor (TH33) and
discharge temperature (TH4)
Abnormality of superheat due
to low discharge temperature
2 blinking Abnormal high pressure (High
pressure switch 63H 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.
OCH771C
Check
Contents
code
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
79
Error
Inspection method
*1
Check if stop valves are open.
Check if connectors (TH4, TH33, LEV-A, and LEV-B)
on outdoor controller board are not disconnected.
Check if unit is filled with specified amount of refrigerant.
Measure resistance values among terminals on indoor valve
and outdoor linear expansion valve using a tester.
Check if indoor/outdoor units have a short cycle on their air ducts.
Check if connector (63H and TRS) on outdoor
controller board is not disconnected.
Check if heat exchanger and filter is not dirty.
Measure resistance values among terminals on
linear expansion valve using a tester.
Check the outdoor fan motor.
Check if connector (TH3) on outdoor controller
board is disconnected.
Check if stop valves are open.
Check looseness, disconnection, and reversed
connection of compressor wiring.
Measure resistance values among terminals on
compressor using a tester.
Check if outdoor unit has a short cycle on its air duct.
Check if connectors(TH3,TH4,TH6 ,TH7 and TH33) on
outdoor controller board and connector (CN3) on outdoor
power board are not disconnected.
Measure resistance value of outdoor thermistors.
Check if indoor/outdoor units have a short cycle on their air ducts.
Measure resistance value of outdoor thermistor(TH8).
Check looseness, disconnection, and reversed
connection of compressor wiring.
Measure resistance value among terminals on
compressor using a tester.
Check if power supply voltage decreases.
Check the wiring of CN52C.
Check if connectors (CN20, CN21, CN29 and
CN44) on indoor controller board are not
disconnected.
Measure resistance value of indoor thermistors.
Check if connector (CN31)(CN4F) on indoor
controller board is not disconnected.
Measure resistance value of indoor thermistors.
Measure resistance value among terminals on
drain pump using a tester.
Check if drain pump works.
Check drain function.
Reversed connection of piping or wiring
Note: The error will be cancelled by turning off
power, and on again.
Check if there are any inclination or clogging in
drain pipe.
Check if drain pan or drain sensor is dirty.
Check if any foreign matter is attached to the
moving part of float switch.
Check LEV for proper function.
Check if indoor unit has a short cycle on its air duct.
Check if heat exchanger and filter is not dirty.
Measure resistance value on indoor and outdoor fan
motors.
Check if the inside of refrigerant piping is not clogged.
Check if indoor thermistors(TH2 and TH5) are not
disconnected from holder.
Check if stop valve is open.
Check reversed connection of extension pipe. (on
plural units connection)
Check if indoor/outdoor connecting wire is
connected correctly. (on plural units connection)
Detailed
reference
page
P. 42
P. 43
P. 42
P. 43
P. 45
P. 45
P. 46
P. 45
P. 43
P. 42
P. 43
P. 43
P. 44
–P. 45
*2
*2
*2
*2
*2
*2
*2
*2
*2