23
9-3. INSTRUCTION OF TROUBLESHOOTING
Indoor unit operates.
Outdoor unit does not
operate.
Indoor unit does not
receive the signal
from remote control-
ler.
OPERATION INDICATOR
lamp on the indoor unit is
blinking ON and OFF.
Outdoor unit
operates only
in Test Run
operation.
*1
Indoor unit oper-
ates, when Emer-
gency operation
switch is pressed.
Indoor unit does
not operate,
when Emergency
operation switch
is pressed.
Check room
temperature
thermistor.
Refer to 9-7.
"Test point
diagram and
voltage".
Refer to 9-6.
"Check of remote
controller and
indoor electronic
control P.C. board".
1. Check indoor/out-
door connecting wire.
(Check if the power is
supplied to the indoor
unit.)
2. Check the outdoor fuse (F).
3. Refer to 9-6. "Check
of indoor P.C. board
and indoor fan motor".
Upper lamp
2-time blink
Cause:
Indoor unit
• Trouble
of room
temperature
/ indoor coil
thermistor
Upper lamp
3-time blink
Cause:
Indoor unit
• Trouble of
indoor fan
motor
Upper lamp
4-time blink
Cause:
Indoor unit
• Trouble
of indoor
unit control
system
Start
Check room
temperature
thermistor
and indoor
coil thermis-
tor. Refer to
9-7. "Test
point diagram
and voltage".
Refer to
9-6. "Check
of indoor fan
motor".
Replace the
indoor elec-
tronic control
P.C. board.
Outdoor unit
does not
operate even
in "Test run
operation".
1. Check
the wiring
diagram of
the outdoor
unit.
2. Check the
outdoor
fuse.
Check the
indoor fuse
(F11), outdoor
fuse (F) and
the compres-
sor contactor
(52C).
Indoor and outdoor
unit do not operate.
If blinking of OPERATION INDI-
CATOR lamp cannot be checked,
it can be checked with failure
mode recall function.
Upper lamp
14-time blink
Cause:
Outdoor unit
• Troubles regarding
refrigerant circuit
Refer to 9-4 No. 4
"Remedy".
• Check “Flow chart of
the detailed outdoor
unit failure mode
recall function.”
• Check thermistors.
Refer to “Test point
diagram and voltage”
in the service manual
of indoor unit.
Refer to outdoor unit service manual.
*1 "Test Run operation" means the operation within 30 minutes after the emergency operation switch is pressed.
If blinking of OPERATION INDICATOR lamp cannot be checked, it can be checked with failure mode recall function.
*2 There is possibility that diesel explosion may occur due to the air mixed in the refrigerant circuit.
First, ensure that there are no leakage points on the valves, flare connections, etc. that allow the air to flow into the refriger
-
ant circuit, or no blockage points (e.g. clogged or closed valves) in the refrigerant circuit that cause an increase in pressure.
If there is no abnormal point like above and the system operates cooling mode normally, the indoor thermistor might have a
problem, resulting in false detection.
Check both the indoor coil thermistor and the room temperature thermistor, and replace faulty thermistor(s), if any.
(Do not start the operation again without repair to prevent hazards.)
*2
MS-CP13VA MS-CP18VA MS-CP24VA
OBH782A
