Mitsubishi Electric PUZ-SM100VKA2 Service Manual page 37

Check code
Abnormal points and detection method
Abnormal if a connection of indoor unit
and outdoor unit which uses different
refrigerant is detected.
EE
Non defined check code
This code is displayed when non defined
EF
check code is received.
(6607
or
6608)
Serial communication error
Abnormal if serial communication
between outdoor controller circuit board
and outdoor power circuit board is defec-
tive.
Ed
(0403)
Abnormal if communication between
outdoor controller circuit board and
M-NET board is not available.
Pipe temperature
Detected as abnormal when the pipe
temperature is not in the cooling range
3 minutes after compressor start and
6 minutes after the liquid or condenser/
evaporator pipe is out of cooling range.
Note 1) It takes at least 9 minutes to detect.
Note 2) Abnormality P8 is not detected in
drying mode.
Cooling range: Indoor pipe temperature
(TH2 or TH5) − intake temperature
(TH1) ≤ −3°C
TH: Lower temperature between liquid pipe
temperature and condenser/evaporator
temperature
P8
OCH774A
Cause
Unauthorized connection of indoor
unit and outdoor unit Connections
other than below combination are
not authorized;
Outdoor unit: Models with R32 refrigerant
Indoor unit: Floor standing type
indoor unit (PSA-KA)
Noise has entered transmission
wire of remote controller.
Noise has entered indoor/ out-
door unit connecting wire.
Outdoor unit is not a series of
power-inverter.
Breaking of wire or contact
failure of connector CN2
between the outdoor controller
circuit board and the outdoor
power circuit board
Breaking of wire or contact
failure of connector CN4
between the outdoor controller
circuit board and the outdoor
power circuit board
Defective communication circuit
of outdoor power circuit board
Defective communication circuit
of outdoor controller circuit board
for outdoor power circuit board
Breaking of wire or contact
failure of connector between
outdoor controller circuit board
and M-NET board
Contact failure of M-NET board
power supply line
Noise has entered into M-NET
transmission wire.
Slight temperature difference
between indoor room
temperature and pipe <liquid
or condenser/evaporator>
temperature thermistor
• Shortage of refrigerant
• Disconnected holder of
pipe <liquid or condenser/
evaporator> thermistor
• Defective refrigerant circuit
Reverse connection of
extension pipe (on plural units
connection)
Reverse wiring of indoor/
outdoor unit connecting wire
(on plural units connection)
Defective detection of indoor
room temperature and pipe
<condenser/evaporator>
temperature thermistor
Stop valve is not opened
completely.
37
Judgment and action
Alter the connection referring to the combina-
tion as shown in the "cause" column.
Turn the power off, and on again to check.
Replace indoor controller board or outdoor
controller circuit board if abnormality is
displayed again.
Replace outdoor unit with power-inverter type
outdoor unit.
Check connection of each connector CN2
and CN4 between the outdoor controller
circuit board and the outdoor power circuit
board.
Replace outdoor power circuit board.
Replace outdoor controller circuit board.
Check disconnection, looseness, or breaking
of connection wire between outdoor control-
ler circuit board (CNMNT) and M-NET board
(CN5).
Check disconnection, looseness, or breaking
of connection wire between outdoor control-
ler circuit board (CNMNT) and M-NET board
(CND).
Check M-NET transmission wiring method.
– Check pipe <liquid or condenser/
evaporator> temperature with room
temperature display on remote controller
and outdoor controller circuit board.
Pipe <liquid or condenser / evaporator>
temperature display is indicated by setting
SW2 of outdoor controller circuit board as
follows.
(
Conduct temperature check with outdoor
controller circuit board after connecting
'A-Control Service Tool (PAC-SK52ST)'.
Temperature display of indoor condenser/
Temperature display of indoor liquid pipe
evaporator pipe Indoor 1
Indoor 1
1 2 3 4 5 6 1 2
ON
OFF
Temperature display of indoor condenser/
Temperature display of indoor liquid pipe
evaporator pipe Indoor 2
Indoor 2
1 2 3 4 5 6 1 2
ON
OFF
A-Control Service Tool SW2 setting
Check reverse connection of extension
pipe or reverse wiring of indoor/outdoor unit
connecting wire.
)
3 4 5 6
ON
OFF
3 4 5 6
ON
OFF