43
11-2. Instruction of troubleshooting
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate.
Indoor unit
doesn't receive
the signal from
remote controller.
Indoor unit
operates.
Outdoor unit
doesn't operate
normally.
OPERATION INDICATOR
lamp on the indoor unit is
flashing on and off.
Outdoor unit
operates in
only Test Run
operation.
Outdoor unit
doesn't
operate
even in
Test Run
operation.
Indoor unit
operates, when
the EMERGENCY
OPERATION
switch is pressed.
Indoor unit
doesn't operate,
when the
EMERGENCY
OPERATION
switch is pressed.
Check room
temperature
thermistor.
Refer to
"Test point
diagram and
voltage" on
page 52.
Refer to
D
"Check of
outdoor unit"
on page 47 or
48.
Refer to
F
"Check of
outdoor unit"
on page 50.
Refer to
B
"Check of
remote controller
and receiver
P.C. board"
on page 46.
Flash on and
off at 0.5-
second
interval
Cause:
Indoor/
Outdoor unit
• Mis-wiring
2-time flash
Cause:
Indoor unit
• Trouble of
room temp-
erature/
indoor coil
temperature
thermistor
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
Check room
temperature
thermistor
and indoor
coil tempera-
ture thermis-
tor.
Refer to
"Test point
diagram and
voltage"
on page 52.
Refer to
H
"Check of
outdoor
thermistor"
on page 51.
MCHF-24NV
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Refer the
deicer
P.C. board.
1-time flash
Cause:
Outdoor /
Indoor unit
• Trouble of
serial signal
Refer to
E
"How to
check mis-
wiring and
serial signal
error (When
outdoor unit
doesn't
work)" on
page 49.
W
1
Refer to
E
"How to
check mis-
wiring and
serial signal
error (When
outdoor unit
doesn't
work)" on
page 49.
W
1
1. Check indoor /
outdoor
connecting wire.
2. Refer to
C
"Check of indoor
electronic control
P.C. board"
on page 47.
Outdoor unit
doesn't
stop even
if indoor unit
stops.
Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.
Refer to
G
"Check of
R.V. coil"
on page 50.
W
1.<The case of the trouble of the serial signal>
When the power is turned off and then turned on again, the indication shows “the trouble of mis-wiring”.
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