VANE MOTOR
VARISTOR
ROOM TEMPERATURE THERMISTOR
INDOOR COIL THERMISTOR
6
HIC1
F11
E1E1E1
CN
112
LDCOM
LDC11
C11
X144
SR143
SR142
LDC12
LDFH
LDFM
LDFL
NR11
SYMBOLNAME
SR142~SR143
TB1, TB2
X144
22
RT12
WHT
ORN
RED
BLK
YLW
BLU
WHT
1
ORN
2
RED
3
BLK
4
YLW
5
BLU
6
BRN
7
8
GRN/YLW
SOLID STATE RELAY
TERMINAL BLOCK
RELAY
MF
REFRIGERANT SYSTEM DIAGRAM7
MCF-GA35VB -
INDOOR UNIT
Indoor
heat
exchanger
Indoor coil
thermistor
RT12
Room temperature
thermistor
RT11
Distributor
E1
Refrigerant pipe [12.7
(with heat insulator)
Flared connection
Flared connection
Refrigerant pipe
[6.35
(with heat insulator)
MCF-GA50VB -
INDOOR UNIT
Indoor
heat
exchanger
Indoor coil
thermistor
RT12
Room temperature
thermistor
RT11
Distributor
E1
Refrigerant pipe [12.7
(with heat insulator)
Flared connection
Flared connection
Refrigerant pipe
[6.35
(with heat insulator)
Unit : mm
MCF-GA60VB -
INDOOR UNIT
Indoor
heat
exchanger
Indoor coil
thermistor
RT12
Room temperature
thermistor
RT11
Distributor
E1
Refrigerant pipe [15.88
(with heat insulator)
Flared connection
Flared connection
Refrigerant pipe
[6.35
(with heat insulator)
Refrigerant flow in cooling
Refrigerant flow in heating
7
8
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
SERVICE FUNCTIONS
MCF-GA35VB -MCF-GA50VB -MCF-GA60VB -
E1E1E1
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;
Remote controller model : KM04N
NOTE : For remodelling, take out the bat-
teries 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.
J1J2
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.
Table1.
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.
8
JR07
CN151CN113CN112
CN101
CN105
SW2
CN102
CN201
SW1
IC101
C11
TAB12
8-3. AUTO RESTART FUNCTION
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 CONTROL” mode before power failure, the operation is not memorized. In “I FEEL CONTROL” mode, the operation is decided
by the initial room temperature.
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.)
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..)
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.
9
9
Insert the negative pole
of the batteries first.
Check if the polarity of
the batteries are correct.
RESET button
TROUBLESHOOTING
MCF-GA35VB -MCF-GA50VB -MCF-GA60VB -
E1E1E1
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 servicing.
(1) Before servicing the air conditioner, be sure to turn off the main unit first with the remote controller, and then after con-
firming the horizontal vane is closed, turn off the breaker and / or disconnect the power plug.
(2) Be sure to turn OFF the power supply before removing the front panel, the cabinet, the top panel, and the electronic
control P.C. board.
(3) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the com-
ponents.
(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)Before servicing that the connector and terminal are connected properly.
(3) 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.
(4) 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.
1 Remove the front lid and insert batteries.
Then reattach the front lid.
2 Press 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.
10
9-2. Instruction of troubleshooting
OPERATION INDICATOR
lamp
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate.
Indoor unit
doesn't
receive the
signal from
remote
controller.
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".
Check of
wiring
diagram of
outdoor
unit.w
Refer to 9-5.B
"Check of
remote
controller
and receiver
P.C. board".
Refer to 9-5.C
"Check of
indoor
electronic
control
P.C. board".
2-time flash
Cause:
Indoor unit
• Trouble of
room
temperature/
indoor coil
thermistor
Check room
tempreture
thermistor and
indoor coil
thermistor.
Refer to 9-6.
"Test point
diagram and
voltage".
When the
remote
controller is
pressed
or when the
EMERGENCY
OPERATION
switch is
pressed,
the fan doesn't
rotate, with
OPERATION
INDICATOR
lamp on.
Refer to 9-5.A
"Check of
indoor fan
motor".
As for outdoor unit MUCF type, refer to service manual OB383.
w Before checking the outdoor unit, make sure if
any signal or power is being transmitted from
the indoor unit.
4-time flash
Cause:
Indoor unit
• Trouble of
indoor unit
control
system
Replace the
indoor
electronic
control
P.C. board.
No.
1
SymptomOperation indicator lampDetection method
Checkpoint
Indoor coil
thermistor
Abnormal
point
Room
temperature
thermistor
2-time flash
2.5-second OFF
Detect Indoor coil/room temperature
thermistor short or open circuit.
• Check the resistance of
thermistor.
• Reconnect the connector.
• Check the indoor electronic
control P.C.
Outdoor unit
does not
operate.
2
4-time flash
2.5-second OFF
Indoor
control
system
When it cannot properly read data in the
nonvolatile memory of the indoor electronic
control P.C. board.
Outdoor unit
does not
operate.
• Check the indoor electronic
control P.C. board.
9-3. Troubleshooting check table
❈ Before taking measures, make sure that the symptom reappears, for accurate troubleshooting.
Self check table
11
9-4. Trouble criterion of main parts
BLKRED ORNYLWBLU BRN
WHT
GRN
YLW
FUSE
YLW
GRNORN
BRN
RED
ROTOR
MCF-GA35VB -MCF-GA50VB -MCF-GA60VB -
Part name
Room
temperature
thermistor (RT11)
Indoor coil
thermistor (RT12)
Indoor fan
motor
(MF)
INNER FUSE
145 i 5: CUT OFF
Vane
motor
(MV)
Measure the resistance with a tester.
(Part temperature 10°C ~ 30°C)
Normal
8kΩ ~ 20kΩ
Measure the resistance between the terminals with a tester.
(Part temperature 10°C ~ 30°C)
Color of lead
wire
MCF-GA35VB
WHT-BLK
BLK-YLW
YLW-BLU45 ~ 50Ω31 ~ 34Ω
BLU-BRN
BRN-RED
Measure the resistance between the terminals with a tester.
(Part temperature 10°C ~ 30°C)
Normal
329 ~ 357Ω
Check method and criterion
Abnormal
Open or short-circuit
Normal
MCF-GA50VB
MCF-GA60VB
175 ~ 190Ω195 ~ 212Ω
66 ~ 72Ω44 ~ 48Ω
30 ~ 33Ω42 ~ 47Ω
22 ~ 24Ω22 ~ 25Ω
Abnormal
Open or short-circuit
80 ~ 88Ω
44 ~ 49Ω
35 ~ 39Ω
43 ~ 47Ω
13 ~ 15Ω
E1E1E1
Figure
Abnormal
Open or
short-circuit
9-5. Troubleshooting flow
Indoor fan does not operate.
A
Check of indoor fan motor
No
Are lead wires connected?
Reconnect the lead
wires.
Disconnect lead wires from connector (Fan motor).
Measure resistance between lead wires No.1 and No.4 and then No.3 and No.4 of the fan motor.
Turn OFF power supply.
Check connector (Fan motor) visually.
Yes
Is resistance 0 (short circuit) or ∞ (open circuit)?
Yes ( 0 or ∞ )
Replace the indoor fan motor.
Is soldered point of the connector
correctly soldered?
Yes
Replace the indoor electronic control
P.C. board.
No
(others)
No
Resolder it.
12
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote con-
● Reinstall the unit away from lights.
● Attach a filter on receiving part.
Switch on the remote controller
Is LCD display on remote controller
visible?
Replace the batteries.(Refer to 9-1..)
Remove batteries and then set them back and press
the RESET button. Check if the unit operates with
remote controller.
Does the unit operate with remote controller?
Turn on a radio to AM and press
switch on remote controller.
Is noise heard from radio?
Replace the remote controller.
Are there any fluorescent lights
of inverter or rapid-start type
within the range of 1m?
Measure the voltage between receiver P.C.board connector No.2(+)and No.1 when remote controller button is pressed.
Is the voltage approx. 4V DC?
No
(5V DC or 0V DC)
Replace the receiver.
No
(not clear)
Yes
Yes
No
OK
No
Yes
Yes
Yes
No
Replace the indoor
electronic control P.C. board.
No
troller.
Check of remote controller and receiver P.C. board
B
w Check if the remote controller is exclusive for this air conditioner.
The unit doesn’t operate with the remote controller.
Also, the OPERATION INDICATOR lamp doesn’t light up by pressing the EMERGENCY OPERATION switch.
Check of indoor electronic control P.C. board
C
Check both “parts side”and “pattern
side” of indoor electronic control P.C.
board visually.
Be sure to check both fuse
and varistor in any case.
Replace the fuse.
Is fuse(F11)blown?
Is varistor(NR11)burnt?
Replace the varistor.
Yes
No
Trouble of the indoor electronic
control P.C. board.
No
Yes
13
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')
9-6. Test point diagram and voltage
MCF-GA35VB -MCF-GA50VB -MCF-GA60VB -
Indoor electronic control P.C. board
Fan motor power supply 230V AC
Med.
Low
654321
High
Fuse (F11)
250V AC
3.15A
Varistor (NR11)
E1E1E1
Power supply
input 230V AC
+
5V DC
}
–
–
12V DC
}
+
No.2 No.1
Receiver P.C.
– +
board connector
(CN101)
Room temperature
thermistor(RT11)
Release of “AUTO RESTART
FUNCTION”
Solder jumper wire to the JR07.
(Refer to 8-3..)
Room temperature thermistor (RT11)
Time short point JPG and JPS
(Refer to 8-1..)
Indoor coil thermistor (RT12)
14
DISASSEMBLY INSTRUCTIONS10
(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
MCF-GA35VB -MCF-GA50VB -MCF-GA60VB INDOOR UNIT
OPERATING PROCEDURE
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 3
Photo 1
Photo 2
E1E1E1
PHOTOS
Screws
Grille
Electronic control P.C. board
Electronic box
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.
15
Photo 4
Fan casing
(upper)
Indoor fan motor
Terminal block
Motor band
Screws
Fan
casing(upper)
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
Screws
Front panel
Photo 6
Nozzle assembly
Photo 7
Photo 8
Screws
Insulation of drain pan and screws
Drain pan
16
screws
PARTS LIST11
Q'ty/unit
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
VANE MOTOR
INSTALLATION METAL (L)
AIR FILTER
GRILLE (WH)
FRONT PANEL (WH)
DRAIN PAN
FAN CASING (U)
FAN CASING (L)
UNION (GAS)
UNION (GAS)
INSTALLATION METAL (R)
UNION (LIQUID)
BACK PANEL (IN)
NOZZLE (WH)
INDOOR HEAT EXCHANGER
INDOOR HEAT EXCHANGER
VANE (WH)
GRILLE CATCH (WH)
Part number that is circled is not shown in the illustration.
65
17
7
1
2
3
4
5
6
7
8
9
10
11
SIROCCO FAN
FAN MOTOR RUBBER MOUNT
INDOOR FAN MOTOR
INDOOR FAN MOTOR
INDOOR FAN MOTOR
TERMINAL BLOCK
TERMINAL BLOCK
RECEIVER P.C. BOARD
INDOOR COIL THERMISTOR
ELECTRONIC CONTROL P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
SWITCH & ROOM TEMPERATURE THERMISTOR P.C. BOARD
VARISTOR
FUSE