Mitsubishi MUX-2A28VB Service Manual page 57

11-2. Instruction of troubleshooting
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate.
Outdoor unit Outdoor unit
operates in doesn't
only Test Run operate
operation. even in
Test Run
operation.
Check room
Refer to 11-4.A
temperature
"Check of
thermistor.
outdoor unit".
Refer to
"Test point
diagram and
voltage".
Flash on and
2-time flash
off at 0.5-second
Cause:
intervals
Indoor unit
Cause:
• Trouble of
Wrong setting
of switch (SW2-2)
on the electronic
control P.C. board.
Refer to 11-4.C
"Check of
MU & MUX TYPE /
MUH & MXZ TYPE
SWITCH OVER "
(When
outdoor unit
doesn't work.).
Indoor unit
operates.
Outdoor unit
doesn't operate
normally.
Outdoor unit
doesn't
stop even
if indoor unit
stops.
Refer to 11-4.B
"Check of
outdoor unit".
3-time flash
Cause:
Indoor unit
• Trouble of
room temp-
indoor fan
erature/
motor
indoor coil
thermistor
Check room
Refer to
temperature
"Check of
thermistor
indoor fan
and indoor
motor".
coil thermis-
tor.
Refer to
"Test point
diagram and
voltage".
Indoor unit
doesn't receive
the signal from
remote controller.
Indoor unit
Indoor unit
doesn't operate,
operates,
when the
when the
EMERGENCY
EMERGENCY
OPERATION
OPERATION
switch is
switch is
pressed.
pressed.
1. Check indoor /
Refer to
outdoor
"Check of
connecting wire.
remote
2. Refer to
controller
"Check of indoor
and receiver
electronic control
P.C. board".
P.C. board".
As for indoor unit MSC-CA type, refer to
service manual OB393.
As for indoor unit MSC-GA type, refer to
service manual OB385.
57
OPERATION Indoor unit
INDICATOR operates.
lamp on the But indoor
indoor unit is unit doesn't
flashing on blow out
and off. cool air.
Refer to 11-4.D
"Check of
indoor / outdoor
units' connection
and outdoor unit".