Mitsubishi Electric MCFH-GA35VB User manual

SERVICE MANUAL
Wireless type
Models
MCFH-GA35VB- (WH)
MCFH-GA50VB- (WH)
MCFH-GA60VB- (WH)
E1
E1
E1
No. OB380
(When installed on the ceiling)
(When installed on the floor)
FLOOR AND CEILING TYPE AIR CONDITIONERS
NOTE:
• This manual describes technical data of indoor units
• As for outdoor units MUCFH-GA35VB/GA50VB/GA60VB- , refer to the service manual OB381.
• As for outdoor units MXZ-A14/A18/A26/A32WV- , refer to the service manual OB319 REVISED
EDITION-A. E1
E1
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················2
3. SPECIFICATION·················································4
4. NOISE CRITERIA CURVES·······························5
5. OUTLINES AND DIMENSIONS ·························6
6. WIRING DIAGRAM ············································7
7. REFRIGERANT SYSTEM DIAGRAM················8
8. SERVICE FUNCTIONS ······································9
9. TROUBLESHOOTING······································11
10. DISASSEMBLY INSTRUCTIONS·····················19
11. PARTS LIST······················································21
12. OPTIONAL PARTS···········································23
Indication of
model name
MCFH-GA35VB-
MCFH-GA50VB-
MCFH-GA60VB- E1
E1
E1
OB380--1.qxp 04.12.23 17:33 Page 1

PART NAMES AND FUNCTIONS
2
TECHNICAL CHANGES
2
1
INDOOR UNIT
MCFH-GA35VB - MCFH-GA50VB - MCFH-GA60VB - E1E1E1
(When installed on the floor)
(When the air inlet grille is opened.)
Deodorizing filter
(gray sponge type)(option)
Air filter
Air inlet
Operation section
Air cleaning filter
(white bellows type)(option)
Front panel
Receiving section
Operation indicator lamp
Horizontal vane
Vertical vanes
Emergency
operation switch
(When installed on the ceiling)
ACCESSORIES
Item
Installation plate
Unit fixing screw
5 o12mm
Wireless remote
controller
Remote controller
mounting hardware
Fixing screw for
3.5 o16mm (Black)
Battery (AAA) for
remote controller
Drain hose
Drain pipe cover
Knockout cover
Screw for 4 o10mm
2
2
1
1
2
2
1
1
1
2
Q'ty
Remote controller
MCFH-A12WV- ➔MCFH-GA35VB-
1. Model name has been changed. E1E1
MCFH-A18WV- ➔MCFH-GA50VB-
1. Model name has been changed. E1E1
MCFH-A24WV- ➔MCFH-GA60VB-
1. Model name has been changed. E1E1
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3
REMOTE CONTROLLER
MCFH-GA35VB -
MCFH-GA50VB -
MCFH-GA60VB - E1
E1
E1
ON/OFF
FAN
TOO
WARM TOO COOL
VANE
MODE
ECONO COOL
STOP
START
HR.
MIN.
I FEEL COOL
HEAT
DRY
PM
CLOCK
AM
RESET CLOCK
ON/OFF
TOO
COOL
PM
AM
TOO
WARM
Open the front lid.
Signal transmitting section
Operation display section
OPERATE /STOP
(ON /OFF)button
TEMPERATURE buttons
OPERATION SELECT button
FAN SPEED CONTROL button
OFF-TIMER button
ON-TIMER button
RESET button
ECONO COOL button
VANE CONTROL button
CLOCK SET button
HR. button
MIN. button
(TIME SET button)
Indication of remote controller model
is on back.
OB380--1.qxp 04.12.23 17:33 Page 3

SPECIFICATION
4
3
Indoor model
Function
Power supply
Air flow(High/Med.W/LowW)
Power outlet
Running current
Power input
Auxiliary heater
Power factor
Fan motor current
Model
Winding
resistance(at20:)
Dimensions WOHOD
Weight
Air direction
Sound level(High/Med.W/LowW)
Fan speed(High/Med.W/LowW)
Fan speed regulator
Thermistor RT11(at25:)
Thermistor RT12(at25:)
Remote controller model
K/h
A
A
W
A(kW)
%
A
"
mm
kg
dB
rpm
k"
k"
Electrical data
Fan motor
Special remarks
Capacity
MCFH-GA35VB- E1 MCFH-GA50VB- E1 MCFH-GA60VB- E1
Cooling
—
Heating
—
780/636W/492W
10
0.30
66
96
0.30
RB4V25-AC
WHT-BLK 182.2 BLK-YLW 68.9
YLW-BLU 47.5 BLU-BRN 31.5
BRN-RED 22.9
25
5
46/41W/36W
1,240/1,060/845
3
10
10
KM04M
Cooling
—
Heating
—
Single phase
230V, 50Hz
840/696W/570W
10
0.36
80
97
0.36
RB4V36-AC
WHT-BLK 82.9 BLK-YLW 65.6
YLW-BLU 36.0 BLU-BRN 27.0
BRN-RED 13.7
1100 ✕ 650 ✕ 180
25
5
48/44W/39W
1,320/1,145/960
3
10
10
KM04M
Cooling
—
Heating
—
840/744W/642W
10
0.36
80
97
0.36
RB4V36-DB
WHT-BLK 84.0 BLK-YLW 46.2
YLW-BLU 37.2 BLU-BRN 45.2
BRN-RED 13.6
25
5
48/45W/42W
1,320/1,190/1,060
3
10
10
KM04M
NOTE: Test conditions are based on ISO 5151
Cooling : Indoor DB27°C WB19°C Heating : Indoor DB20°C WB 15°C
Outdoor DB35°C WB(24°C) Outdoor DB 7°C WB 6°C
Indoor-Outdoor piping length : 5 m
wReference value
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5
NOISE CRITERIA CURVES
4
MCFH-GA60VB - E1
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : DB 27: WB 19:\
Heating : DB 20: WB 15:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
HEATING
FUNCTION
High
FAN SPEED
48
SPL(dB(A)) LINE
MCFH-GA35VB - E1
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : DB 27: WB 19:\
Heating : DB 20: WB 15:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
HEATING
FUNCTION
High
FAN SPEED
46
SPL(dB(A)) LINE
MCFH-GA50VB - E1
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : DB 27: WB 19:\
Heating : DB 20: WB 15:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
HEATING
FUNCTION
High
FAN SPEED
48
SPL(dB(A)) LINE
INDOOR UNIT
WALL
1m 1m
MICROPHONE
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OUTLINES AND DIMENSIONS
6
5
(When installed on the floor)
(When installed on the ceiling)
50cm or more
50cm or more
50cm or more
50cm or more
100cm or more
650 616.5
80.8 906 112.8
114
16
1100
93
77
113 143
180
17042.5
12.7 (MCFH-GA35/GA50VB)
15.88 (MCFH-GA60VB)
Gas line
6.35
Liquid line
Wireless remote controller
162
19
58
INDOOR UNIT
MCFH-GA35VB -
MCFH-GA50VB -
MCFH-GA60VB - E1
E1
E1 Unit: mm
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7
WIRING DIAGRAM6
INDOOR UNIT
TAB12
ELECTRONIC CONTROL P.C BOARD
SR142
SR143
X144
CN201
BRN
RECEIVER
P.C.BOARD
CONTROLLER
REMOTE
DISP/
12V
CONNECTING
TO OUTDOOR
UNIT
3
N
RT11
P.C.BOARD
SW/THERMO
113 151101
MV
4
5
55
6
CN CN CN
C11
50Hz
SUPPLY
POWER
L
N1
3
2
7
8
LDFH
LDFL
LDFM
LDC12
LDC11
LDCOM
BLK
BLU
YLW 6
5
4
ORN
RED
WHT 2
3
1
GRN/YLW
BLK MF
BLU
BRN
YLW
ORN
RED
WHT
2
112
CN 2RT12
BLU
RED
BLU
TB1 GRN/YLW
~/N 230V
BRN
SR141
LDFVL
TB2
PE
CIRCUIT BREAKER
HIC1
F11
NR11
MODELS WIRING DIAGRAM
SYMBOL
SR141~SR143
TB1, TB2
X144
SYMBOL
MV
NR11
RT11
RT12
NAME NAME NAME
INDOOR FAN CAPACITOR
FUSE (3.15A)
DC/DC CONVERTER
INDOOR FAN MOTOR(INNER FUSE)
VANE MOTOR
VARISTOR
ROOM TEMPERATURE THERMISTOR
INDOOR COIL THERMISTOR
SOLID STATE RELAY
TERMINAL BLOCK
RELAY
1.About the outdoor side electric wiring refer to the outdoor unit electric wiring diagram for servicing.
2.Use copper conductors only. (For field wiring)
3.Symbols below indicate. : Connector
: Terminal block
NOTES:
SYMBOL
C11
F11
HIC1
MF
MCFH-GA35VB - MCFH-GA50VB - MCFH-GA60VB - E1E1E1
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8
REFRIGERANT SYSTEM DIAGRAM7
INDOOR UNIT
MCFH-GA60VB- E1
Indoor
heat
exchanger
Distributor Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant flow in cooling
Refrigerant flow in heating
Refrigerant pipe [15.88
(with heat insulator)
Refrigerant pipe
[6.35
(with heat insulator)
Indoor coil
thermistor
RT12
Indoor
heat
exchanger
Distributor Flared connection
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT12
Flared connection
Refrigerant pipe [12.7
(with heat insulator)
Refrigerant pipe
[6.35
(with heat insulator)
INDOOR UNIT
MCFH-GA35VB- E1
Indoor
heat
exchanger
Distributor Flared connection
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT12
Flared connection
Refrigerant pipe [12.7
(with heat insulator)
Refrigerant pipe
[6.35
(with heat insulator)
INDOOR UNIT
MCFH-GA50VB- E1
Unit : mm
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9
SERVICE FUNCTIONS8
8-1. TIMER SHORT MODE
For service, set time can be shortened by short circuit of JPG and JPS on the electronic control P.C. board.
The time will be shortened as follows. (Refer to 9-6.)
3-minutes time delay : 3-minutes →3-seconds
Set time : 1 minute ➔ 1-second
Set time : 3 minute ➔ 3-second (It takes 3 minutes for the compressor to start operation. However, the starting time is
shortened by short circuit of JPG and JPS.)
8-2. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION
A maximum of 4 indoor units with wireless remote controllers can be used in a room. In this case, to operate each
indoor unit individually by each remote controller, P.C. boards of remote controller must be modified according to the
number of the indoor unit.
How to modify the remote controller P.C. board
Remove batteries before modification. The board has a print as shown below;
Table1.
No. 1 unit
No. 2 unit
No. 3 unit
No. 4 unit
1 unit operation
No modification
–
–
–
2 units operation
Same as at left
Solder J1
–
–
3 units operation
Same as at left
Same as at left
Solder J2
–
4 units operation
Same as at left
Same as at left
Same as at left
Solder both J1 and J2
The P.C. board has the print “J1” and “J2”. Solder “J1” and “J2” according to the number of indoor unit as shown in
Table 1. After modification, press the RESET button.
How to set the remote controller exclusively for particular indoor unit
After you turn the breaker ON, the first remote controller that sends the signal to the indoor unit will be regarded as the
remote controller for the indoor unit.
The indoor unit will only accepts the signal from the remote controller that has been assigned to the indoor unit once they
are set.
The setting will be cancelled if the breaker has turned off, or the power supply has shut down.
Please conduct the above setting once again after the power has restored.
MCFH-GA35VB - MCFH-GA50VB - MCFH-GA60VB - E1E1E1
Remote controller model : KM04M
NOTE : For remodelling, take out the batteries and
press the OPERATE/STOP(ON/OFF) button
twice or 3 times at first.
After finish remodelling, put back the
batteries then press the RESET button.
J2J1
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10
How to release “AUTO RESTART FUNCTION”
1Turn off the main power for the unit.
2Pull out the electronic control P.C. board. (Refer to 10.)
3Solder jumper wire to the JR07 on the indoor electronic
control P.C. board. (Refer to 9-6.)
JR07
CN151CN113CN112
CN101
CN105
SW2
CN102
CN201
SW1
IC101
C11
TAB12
NOTE
•The operation settings are memorized when 10 seconds have passed after the remote controller was operated with the
remote controller.
•If main power is turned off or a power failure occurs while AUTO START/STOP timer is active ,the timer setting is
cancelled.
•If the unit has been off with the remote controller before power failure, the auto restart function does not work as the
power button of the remote controller is off.
•To prevent breaker off due to the rush of starting current, systematize other home appliances not to turn on at the same
time.
•When some air conditioners are connected to the same supply system, if they are operated before power failure, the
starting current of all the compressors may flow simultaneously at restart.
Therefore, the special counter-measures are required to prevent the main voltage-drop or the rush of the starting current
by adding to the system that allows the units to start one by one.
When the indoor unit is controlled with the remote controller, the operation mode, set temperature, and the fan speed are
memorized by the indoor electronic control P.C. board. The “AUTO RESTART FUNCTION” sets to work the moment power
has restored after power failure.Then, the unit will restart automatically. However if the unit is operated in “I FEEL CON-
TROL” mode before power failure, the operation is not memorized. In “I FEEL CONTROL” mode, the operation is decided
by the initial room temperature.
8-3. AUTO RESTART FUNCTION
Operation
1If the main power (230V AC) has been cut, the operation settings remain.
2After the power is restored, the unit restarts automatically according to the memory.(However, it takes at least 3 minutes
for the compressor to start running.)
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11
TROUBLESHOOTING
9
9-1. Cautions on troubleshooting
1. Before troubleshooting, check the following:
(1) Check the power supply voltage.
(2) Check the indoor/outdoor connecting wire for mis-wiring.
2. Take care the following during service.
(1) Before servicing the air conditioner, be sure to first turn off the remote controller to stop the main unit, and then after
confirming the horizontal vane has completely closed, turn off the breaker.
(2) Be sure to unplug the power cord before removing the air inlet grille, the front panel, the cabinet, the top panel and
the electronic control P.C. boards.
(3) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.
(4) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
3. Troubleshooting procedure
(1) First, check if the OPERATION INDICATOR lamp on the indoor unit is flashing on and off to indicate an abnormality.
To make sure, check how many times the abnormality indication is flashing on and off before starting service work.
(2) If the electronic control P.C. board is supposed to be defective, check the copper foil pattern for disconnection and
the components for bursting and discoloration.
(3) When troubleshooting, refer to 9-2. “Instruction of troubleshooting” and 9-3. “Troubleshooting check table”.
4. How to replace batteries
Weak batteries may cause the remote controller malfunction.
In this case, replace the batteries to operate the remote controller normally.
1Remove the front lid and insert batteries.
Then reattach the front lid. 2Press the RESET button with tip end of ball point
pen or the like, and then use the remote controller.
NOTE : If the RESET button is not pressed, the remote controller may not operate correctly.
MCFH-GA35VB - MCFH-GA50VB - MCFH-GA60VB - E1E1E1
RESET button
Insert the negative pole
of the batteries first.
Check if the polarity of
the batteries are correct.
INFORMATION FOR MULTI SYSTEM AIR CONDITIONER
OUTDOOR UNIT : MXZ-A14WV- MXZ-A18WV- MXZ-A26WV- MXZ-A32WV-
Multi system air conditioner can connect two or more indoor units with one outdoor unit.
•Unit won’t operate in case the total capacity of indoor units exceeds the capacity of outdoor units. Do not connect
indoor units beyond the outdoor unit capacity.
Operation indicator lamp flashes as shown in the figure below.
•When you try to operate two or more indoor units with one outdoor unit simultaneously, one for the cooling and the
other for heating, the operation mode of the indoor unit that operates earlier is selected. The other indoor units that
will start the operation later cannot operate, indicating as shown in the figure below. In this case, please set all the
indoor units to the same operation mode.
•When indoor units starts the operation while the defrosting of outdoor unit is being done, it takes a few minutes
(max. 10 minutes) to blow out the warm air.
•In the heating operation, though indoor unit that does not operate may get warm or the sound of refrigerant flowing
may be heard, they are not malfunction. The reason is that the refrigerant continuously flows into it.
E1E1E1E1
lighted
flashing
Operation Indicator
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12
9-2. 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 9-6.
"Test point
diagram and
voltage".
Refer to
"Check of
outdoor unit".
Refer to
"Check of
outdoor unit".
Refer to 9-5. B
"Check of
remote controller
and receiver
P.C. board".
Flash on and
off at 0.5-
second
interval
Cause:
Indoor/
Outdoor unit
• Mis-wiring
or trouble of
serial signal
2-time flash
Cause:
Indoor unit
• Trouble of
room
temperature/
indoor coil
thermistor
Check room
temperature
thermistor
and indoor
coil
thermistor.
Refer to 9-6.
"Test point
diagram and
voltage".
4-time flash
Cause:
Indoor unit
• Trouble of
indoor
electric
P.C. board
Refer to 9-5.
D "Check
of indoor
electric
control P.C.
board".
Refer to 9-5.E
"How to
check mis-
wiring and
serial signal
error (When
outdoor unit
doesn't
work)".
1. Check indoor /
outdoor
connecting wire.
2. Refer to 9-5. C
"Check of indoor
electronic control
P.C. board".
Outdoor unit
doesn't
stop even
if indoor unit
stops.
Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.
Refer to
"Check of
R.V. coil".
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
MXZ type
MUCFH-GA60VB
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Refer to
"Check of
outdoor
thermistor".
MUCFH-GA60VB
Replace the
deicer
P.C. board.
MXZ type
Replace the
outdoor
electronic
control
P.C. board.
MXZ type
5-time flash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality
Refer to
"Check of
inverter/
compressor"
and "Check
of power
supply".
As for outdoor unit MUCFH type, refer to the service manual OB381.
As for outdoor unit MXZ type, refer to the service manual OB319 REVISED EDITION-A.
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13
9-3. Troubleshooting check table
OPERATION
INDICATOR
lamp
Before taking measures, make sure that the symptom reappears, for accurate troubleshooting.
Self check table
NO.
1
2
4
Abnormal
point
Mis-wiring
or Serial
signal
Indoor coil
thermistor
Room
tempera-
ture ther-
mistor
Outdoor
thermistor
Indication
0.5-second ON
0.5-second OFF
2-time flash
2.5-second OFF
6-time flash
2.5-second OFF
Symptom
Outdoor unit
does not run.
Outdoor unit
does not run.
Outdoor unit
does not run
Detect method
When serial signal stops for 4
to 5 seconds.
Detect Indoor coil/room tem-
perature thermistor short or
open circuit every 8 seconds
during operation.
When the outdoor thermistors
short or open after the
compressor start-up.
Check point
● Check wiring (visual check and conductiv-
ity check).
● Check indoor electronic control
P.C.board.
● Check outdoor deicer P.C. board.
● Check electrical parts.
● Check resistance of thermistor.
● Reconnect connector.
● Check indoor electronic control P.C.
board.
● Check outdoor deicer P.C. board.
● Check resistance of thermistor.
● Reconnect connector.
Refer to service manual OB381 or
OB319 REVISED EDITION-A.
5
MXZ type
Outdoor
power
system
5-time flash
2.5-second OFF
Outdoor unit
does not run
When the compressor
operation is continuously
three times interrupted by
over current protection within
1 minute after start-up , it
stops operation.
● Check the inverter output.
● Check the compressor.
Refer to service manual OB319
REVISED EDITION-A.
6
MCFH-
GA60VB
MXZ type
Outdoor
control
P.C.
board
7-time flash
2.5-second OFF
Outdoor unit
does not run
When it cannot properly read
data in the nonvolatile
memory of the outdoor deicer
P.C. board or outdoor
electronic control P.C. board.
● Check the outdoor deicer P.C. board or
outdoor electronic control P.C. board.
Refer to service manual OB381 or
OB319 REVISED EDITION-A.
7
❈
❈
❈The indication is shown only when the indoor unit connects with the outdoor unit MXZ type.
3Indoor
control
P.C.
board
4-time flash
2.5-second OFF
Indoor unit
does not run
When it cannot properly read
data in the nonvolatile memory
of the indoor electronic control
P.C. board.
● Check indoor electronic control P.C.
board.
MXZ type
Operation
mode
setting
Outdoor unit
operates but
indoor unit does
not operate.
When the operation mode of
each indoor unit is differently
set to COOL(includes DRY)
and HEAT at same time, the
operation mode of indoor unit
that has operated at first has
the priority.
● Unify the operation mode.
Refer to service manual OB319
REVISED EDITION-A.
Operation Indicator
Lighted
Flashing 2.5-second OFF
OB380--1.qxp 04.12.23 17:33 Page 13

Abnormal
Open or
short-circuit
MCFH-GA60VB
80~88Ω
44~49Ω
35~39Ω
43~47Ω
13~15Ω
14
Measure the resistance between the terminals with a tester.
(Part temperature10°C ~ 30°C)
Room
temperature
thermistor (RT11)
9-4. Trouble criterion of main parts
Part name
Indoor coil
thermistor (RT12)
Indoor fan
motor
(MF)
INNER FUSE
145 i 5:CUT OFF
Check method and criterion
Measure the resistance with a tester.
(Part temperature 10°C ~ 30°C)
Figure
Normal
8kΩ~ 20kΩAbnormal
Open or short-circuit
Vane
motor
(MV)
Measure the resistance between the terminals with a tester.
(Part temperature10°C ~ 30°C)
Normal Abnormal
Open or
short-circuit
328~356
Ω
MCFH-GA35VB - MCFH-GA50VB - MCFH-GA60VB - E1E1E1
BLK RED ORNYLW BLU BRN WHT
GRN
YLW
FUSE
YLW
GRNORN
BRN
RED ROTOR
Normal
MCFH-GA50VB
WHT-BLK MCFH-GA35VB 79~87Ω175~190Ω
BLK-YLW 63~69Ω66~72Ω
YLW-BLU 34~38Ω45~50Ω
BLU-BRN 25~29Ω30~33Ω
BRN-RED 13~15Ω22~24Ω
Color of lead
wire
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15
Measure the voltage between receiver P.C.board connector CN101 No.2 and No.1
when remote controller button is pressed.
Yes
Yes
Check of indoor fan motor
A
Check of remote controller and receiver P.C. board
B
Indoor fan does not operate.
Turn OFF power supply.
Check connector (Fan motor) visually.
Replace the indoor fan motor.
Disconnect lead wires from connector (Indoor fan motor).
Measure resistance between lead wires No.1 and No.4 and then No.3 and No.4 of the indoor fan
motor.
Are lead wires connected?
Reconnect the lead wires.
Is soldered point of the connector
correctly soldered?
Replace the indoor electronic control
P.C. board.
Resolder it.
Is resistance 0 (short circuit) or ∞(open circuit)?
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote con-
troller.
Replace the batteries.(Refer to 9-4.)
Turn on a radio to AM and press switch
on remote controller.
Is noise heard from radio?
Are there any fluorescent lights of
inverter or rapid-start type within
the range of 1m?
Is the voltage approx. 4V DC ? Replace the indoor electronic control
P.C. board.
Replace the receiver P.C. board.
Replace the remote controller.
● Reinstall the unit away from lights.
● Attach a filter on receiving part.
Yes ( 0 or ∞)No
(others)
Yes
No
Yes
No
Is LCD display on remote
controller visible?
Remove the batteries, then set them back
and press the RESET button. Check if the
unit operates with the remote controller.
Yes
Does the unit operate with remote
controller?
Yes
OK
No
(not clear)
Yes
No
No
No(5V or 0V DC)
No
+–
Switch on the remote controller.
wCheck if the remote controller is exclusive for this air conditioner.
9-5. Troubleshooting flow
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16
Check of indoor electronic control P.C. board
C
The unit does not operate with the remote controller.
Also, the OPERATION INDICATOR lamp doesn’t light up by pressing the EMERGENCY OPERATION switch.
Replace the fuse.
Trouble of the indoor electronic
control P.C. board.
Replace the varistor.
Yes
Check both “parts side”and “pattern
side” of indoor electronic control P.C.
board visually.
No
Is varistor(NR11)burnt?
Yes
Is fuse(F11)blown?
Check of indoor electronic control P.C. board
D
When OPERATION INDICATOR lamp flashes 4 - time.
Indoor unit does not operate.
Turn off the power supply.
Replace the indoor electronic
control P.C. board.
No
OB380--1.qxp 04.12.23 17:33 Page 16

How to check mis-wiring and serial signal error (when outdoor unit does not work)
E
17
When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second.
Outdoor unit does not operate.
1. Turn OFF the power supply(indoor/outdoor unit) and disconnect indoor and outdoor connecting wire on indoor side.
2. Short-circuit between indoor terminal block N and 3.
3. Turn ON the power supply(indoor unit) and press once EMERGENCY OPERATION switch.
During EMERGENCY OPERATION,
is there 10V DC between both ends
of R601?
(By tester, the stylus is between 5 ~10V)
Start
No
No
Is there 20V DC between both ends of
R132 on indoor electronic control P.C.
board ?
( By tester, the stylus is between 0 ~ 20V. )
•Turn OFF the power supply(indoor unit).
•Connect ON indoor and outdoor connecting wire.
Is this mis-wiring, poor contact,
or disconnection of wire?
Make them sure.
Replace the indoor electronic
control P.C. board.
Turn ON the power supply(outdoor unit).
Is there 230V AC between outdoor terminal
block L-N(TB1)? No Check the outdoor power supply,
power supply cord and
connection.
Yes
Turn ON the power supply(indoor unit).
No Replace the deicer P.C. board.
Yes
No Make the wiring between CN730
on the deicer P.C. board and
outdoor terminal block correct.
Replace the deicer P.C. board.
Yes
Yes
Yes
Is there 5V DC between J205 + –J101 - (MUCFH-GA35VB/GA50VB)/
J101 + –J401 - (MUCFH-GA60VB) on the deicer P.C. board?
As for outdoor unit MUCFH type, refer to the service manual OB381.
As for outdoor unit MXZ type, refer to the service manual OB319 REVISED EDITION-A.
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18
DE00R697B
To the indoor
electronic control
P.C.board CN113
Indoor coil thermistor (RT12)
Room temperature thermistor (RT11)
RT11
EMERGENCY OPERATION switch
TH113 CH313
GILMS
1 2
0
0
10
20
30
40
10 20 30 40 50 60
Temperature ( C)
Resistance (K')
MCFH-GA35VB -
MCFH-GA50VB -
MCFH-GA60VB - E1
E1
E1
Indoor electronic control P.C. board
Fan motor power supply 230V AC
7 5 6 4 3 2 1 8
Med. High Fuse (F11)
250V AC
3.15A
Power supply
input 230V AC
12V DC
5V DC
–
+
+
–
Time short point JPG and JPS
(Refer to 8-1.)
Indoor coil thermistor (RT12)
Room temperature
thermistor(RT11)
Very
Low Low
Solder jumper wire to the
JR07 on the indoor electronic
control P.C. board.
(Refer to 8-3.)
}
}
Room temperature thermistor (RT11)
Varistor (NR11)
– +
Receiver P.C.
board connector
(CN101)
No.2 No.1
R132 about 20V DC
(Refer to 9-5.E.)
9-6. Test point diagram and voltage
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19
DISASSEMBLY INSTRUCTIONS10
OPERATING PROCEDURE PHOTOS
1. Removing the electronic control P. C . board.
(1) Pull out the upper part of the grille. (See Photo 1.)
(2) Remove the screws of the grille.
(3) Remove screws of terminal block cover.
Remove the terminal block cover and remove the terminal
block.
(4) Remove the screws of the electronic box cover.
(5) Pull out the electronic control P. C. board.
Photo 1
Photo 2
Photo 3
Screws
Electronic box Terminal block
10-1.MCFH-GA35VB- MCFH-GA50VB- MCFH-GA60VB-
INDOOR UNIT E1E1E1
Electronic control P.C. board
(1) Slide the sleeve and check if there is a locking lever or not. (2) The terminal with this connector has the locking
mechanism.
1Slide the sleeve.
2Pull the terminal while
pushing the locking
lever.
1Hold the sleeve, and
pull out the terminal
slowly.
The terminal which has the locking mechanism can be detached as shown below.
There are two types ( Refer to (1) and (2)) of the terminal with locking mechanism.
The terminal without locking mechanism can be detached by pulling it out.
Check the shape of the terminal before detaching.
<"Terminal with locking mechanism" Detaching points>
Connector
Sleeve
Locking lever
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20
OPERATING PROCEDURE PHOTOS
3. Removing the indoor heat exchanger.
(1) Remove the grille. (Refer to 1(1) (2).)
(2) Remove the screws on both side and in front of the front
panel. (See Photo 5.)
(3) Remove the screws of the nozzle assembly. (See Photo 6.)
(4) Remove the electronic box. (Refer to 1.)
(5) Remove the indoor fan motor. (Refer to 2.)
(6) Remove the screws of the motor support .
(7) Remove the fan casing. (Iower)
(8) Remove the insulation of the drain pan and remove the
screws. (See Photo 7.)
(9) Remove the screws under the drain pan. (See Photo 8.)
( 10 ) Remove the drain pan.
( 11 ) Remove the indoor heat exchanger.
Photo 5
Photo 6
Photo 7
Photo 8
Screws
Insulation and screws
screws
Screws
2. Removing the indoor fan motor
(1) Remove the grille. (Refer to 1(1) (2).)
(2) Remove the fan casing.(upper)
(3) Disconnect the connector of the indoor fan motor.
(4) Disconnect the ground wire of the fan motor.
(5) Remove the screws of the motor band and remove the
catch.
(6) Take out the sirocco fan and the indoor fan motor.
Photo 4
Fan casing
(upper)
Indoor fan motor
Screws Fan
casing(upper)
Motor band
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