Mitsubishi Electric PUHZ-P100VHA.UK Service Manual page 61

Indication
Outdoor controller board
LED1 (Green) LED2 (Red)
3 blinking 1 blinking
Abnormality of shell thermostat
and discharging temperature (TH4)
2 blinking Abnormal high pressure (High
pressure switch 63H worked.)
3 blinking
Abnormality of outdoor fan
motor rotational speed
Protection from overheat operation (TH3)
4 blinking Compressor over current breaking (Start-up locked)
Compressor over current breaking
Abnormality of current sensor (P.B.)
Abnormality of power module
Open/short of discharge thermistor (TH4)
5 blinking
Open/short of outdoor thermistors
(TH3, TH6, TH7 and TH8)
Open/short of outdoor ther-
mistor (TH8)
6 blinking Abnormality of radiator panel
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)
Indoor drain overflow protection
3 blinking Freezing (cooling)/overheating
(heating) protection
4 blinking
Abnormality of pipe
temperature
W1 Error code displayed on remote controller
W2 Refer to service manual for indoor unit.
Error
Contents
code
w1
1Check if stop valves are open.
U2
2Check if connectors (TH4, LEV-A) on outdoor controller board are not
3Check if unit fills with specified amount of refrigerant.
4Measure resistance values among terminals on indoor valve and outdoor linear
U1
1Check if indoor/outdoor units have a short cycle on their air ducts.
2Check if connector (63H) on outdoor controller board is not disconnected.
3Check if heat exchanger and filter is not dirty.
4Measure resistance values among terminals on linear expansion valve using a
1Check the outdoor fan motor.
U8
2Check if the connector of TH3 on outdoor controller board is disconnected.
Ud
UF
1Check if stop valves are open.
2Check looseness, disconnection, and converse connection of compressor wiring.
UP
3Measure resistance values among terminals on compressor using a tester.
4Check if outdoor unit has a short cycle on its air duct.
UH
U6
1Check if connectors (TH3, TH4, TH6 and TH7) on outdoor controller board and conn-
U3
U4
2Measure resistance value of outdoor thermistors.
1Check if indoor/outdoor units have a short cycle on their air ducts.
U5
2Measure resistance value of outdoor thermistor(TH8).
1Check looseness, disconnection, and converse connection of compressor wiring.
U9
2Measure resistance value among terminals on compressor using a tester.
3Check the continuity of contactor (52C).
4Check if power supply voltage decreases.
5Check the wiring of CNAF.
P1
1Check if connectors (CN20, CN21 and CN29) on indoor controller board are not
P2
2Measure resistance value of indoor thermistors.
P9
P4
1Check if connector (CN31) on indoor controller board is not disconnected.
2Measure resistance value of indoor thermistors.
P5
3Measure resistance value among terminals on drain-up machine using a tester.
4Check if drain-up machine works.
5Check drain function.
P6
1Check if indoor unit has a short cycle on its air duct.
2Check if heat exchanger and filter is not dirty.
3Measure resistance value on indoor and outdoor fan motors.
4Check if the inside of refrigerant piping is not clogged.
1Check if indoor thermistors (TH2 and TH5) are not disconnected from holder.
P8
2Check if stop valve is open.
3Check converse connection of extension pipe. (on plural units connection)
4Check if indoor/outdoor connecting wire is connected correctly. (on plural units
Error
Inspection method
disconnected.
expansion valve using a tester.
tester.
ector (CN3) on outdoor power board are not disconnected.
disconnected.
connection)
61
Detailed
reference
page
P.30
P.30
P.32
P.32
P.33
P.32
P.31
P.31
P.31
P.31
P.32
W2
W2
W2
W2
W2
W2