Revision A:
• Another type of the electronic control P.C.
board (TYPE 2) has been added to the
original one (TYPE 1). They are both compatible with MS/MSH-GE50VB- E1 .
SPLIT-TYPE AIR CONDITIONERS
Please void OBH529.
INDOOR UNIT
No. OBH529
SERVICE MANUAL
Models
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
MS-GE50VB
MSH-GE50VB
-
REVISED EDITION-A
E1
E1
E1
Outdoor unit service manual
MU-GA•VB Series (OB386)
MUH-GA•VB Series (OB387)
MUX-A•VB Series (OB384)
MXZ-A•WV Series (OB319)
MU/MUH-GE•VB Series (OBH530)
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 ························ 7
6. WIRING DIAGRAM············································ 9
7. REFRIGERANT SYSTEM DIAGRAM ············· 10
8. SERVICE FUNCTIONS ····································11
9. MICROPROCESSOR CONTROL ··················· 14
10. TROUBLESHOOTING ····································· 22
11. DISASSEMBLY INSTRUCTIONS ···················· 33
PARTS CATALOG (OBB529)
NOTE:
RoHS compliant products have <G> mark on the spec name plate.
Use the specified refrigerant only
Never use any refrigerant other than that specified.
Doing so may cause a burst, an explosion, or fire when the unit is being used, serviced, or disposed of.
Correct refrigerant is specified in the manuals and on the spec labels provided with our products.
We will not be held responsible for mechanical failure, system malfunction, unit breakdown or accidents caused by
failure to follow the instructions.
Revision A:
• Another type of the electronic control P.C. board (TYPE 2) has been added to the original one (TYPE 1). They are both compatible with MS/MSH-GE50VB- E1 .
1
TECHNICAL CHANGES
MSC-GA20VB - E1
MSC-GA25VB - E1
MSC-GA35VB - E1
MSC-GE20VB - E1
→ MSC-GE25VB - E1
→ MSC-GE35VB - E1
→
1. Front panel has been changed.
MS-GA50VB - E1
→
MS-GE50VB - E1
1. Indoor fan motor has been changed. (RC4V32-AA
MSH-GA50VB - E1
→
MSH-GE50VB - E1
1. Indoor fan motor has been changed. (RC4V32-AA
2
RC4V32-BA)
RC4V32-BA)
PART NAMES AND FUNCTIONS
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
Front panel
Air cleaning filter(option)
(White bellows type)
Air inlet
to Breaker
Panel
Power supply cord
Catechin air filter
Remote control
receiving section
Air outlet
Vertical vanes
Fan
Horizontal vane
Remote controller
Display section
Operation section
(When the front panel is opened)
Operation indicator lamp
Emergency operation switch
OBH529A
Remote control
receiving section
2
MS-GE50VB
MSH-GE50VB
Air cleaning filter (option)
(White bellows type)
Front panel
Air inlet
To breaker
Panel
Power supply cord
Catechin air filter
Remote control
receiving section
Vertical vanes
Horizontal vane
Remote controller
Operation section
Display section
(When the grille is opened)
Operation indicator lamp
Emergency operation switch
Remote control
receiving section
ACCESSORIES
Installation plate
Installation plate fixing screw 4 25 mm
Remote controller holder
Fixing screw for
3.5 1.6 mm (Black)
Battery (AAA) for remote controller
Wireless remote controller
Felt tape (Used for left or left-rear piping)
OBH529A
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
MS-GE50VB
MSH-GE50VB
1
5
1
2
2
1
1
1
7
1
2
2
1
1
3
SPECIFICATION
3
MSC-GE20VB
Indoor model
Function
Power supply
Special
remarks
Fan Electrical
motor data
Breaker capacity
Running current
Power input
Power factor
Model
Fan motor current
Dimensions W H D
Weight
Air direction
Air flow (High/Med./Low)
Sound level (High/Med./Low)
Fan speed (High/Med./Low)
Fan speed regulator
Remote controller model
A
A
W
%
A
mm
kg
m3/h
dB
rpm
Heating
Cooling
Single phase
230 V, 50 Hz
10
0.17
35
90
RC4V19-JA
0.17
815 278 244
9
5
474/372/276 510/420/342
36/31/25
36/31/25
900/750/600 950/820/700
3
KM04F
Indoor model
MS-GE50VB
Function
Cooling
Single phase
230 V, 50 Hz
Fan
Electrical data
motor
Power supply
MSC-GE25VB
MSC-GE35VB
Heating
Cooling
Single phase
230 V, 50 Hz
10
0.17
35
90
RC4V19-JA
0.17
815 278 244
9
5
474/384/306 588/456/342
36/31/25
39/32/25
900/770/650 1,050/870/700
3
KM04F
Heating
Cooling
Single phase
230 V, 50 Hz
10
0.19
40
92
RC4V19-HA
0.19
815 278 244
10
5
582/444/324 606/498/396
40/33/26
39/33/26
930/760/600 960/830/700
3
KM04F
MSH-GE50VB
Cooling
Heating
Single phase
230 V, 50 Hz
Breaker capacity
Running current
Power input
Power factor
A
A
W
%
Model
Fan motor current
10
0.3
60
87
RC4V32-BA
10
0.3
60
87
RC4V32-BA
A
0.3
1,100 325 258
16
5
768/642/516
42/38/34
1,070/920/780
3
0.3
1,100 325 258
16
5
768/642/516
42/38/34
1,070/920/780
3
KM04B
KM04A
Special
remarks
Dimensions W H D
Weight
Air direction
Air flow (High/Med./Low)
Sound level (High/Med./Low)
Fan speed (High/Med./Low)
Fan speed regulator
Remote controller model
mm
kg
/h
dB
rpm
NOTE: Test conditions are based on ISO 5151.
Cooling: Indoor Dry-bulb temperature 27°C
Outdoor Dry-bulb temperature 35°C
Heating: Indoor Dry-bulb temperature 20°C
Outdoor Dry-bulb temperature 7°C
Indoor-Outdoor piping length: 5 m
OBH529A
Wet-bulb temperature 19 °C
Wet-bulb temperature 24 °C
Wet-bulb temperature - °C
Wet-bulb temperature 6°C
4
NOISE CRITERIA CURVES
4
MSC-GE20VB
COOLING
High
90
MSC-GE25VB
LINE
High
Test conditions,
Cooling : Dry-bulb temperature 27
Heating : Dry-bulb temperature 20
Wet-bulb temperature19
Wet-bulb temperature -
90
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
80
70
NC-70
60
NC-60
50
NC-50
40
NC-40
30
NC-30
20
SPL(dB(A))
FAN SPEED FUNCTION
36
HEATING
Test conditions,
Cooling : Dry-bulb temperature 27
Heating : Dry-bulb temperature 20
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
SPL(dB(A))
FAN SPEED FUNCTION
COOLING
36
HEATING
39
Wet-bulb temperature 19
Wet-bulb temperature -
80
70
NC-70
60
NC-60
50
NC-50
40
NC-40
30
NC-30
20
NC-20
10
NC-20
NC-10
63
125
250
500
1000
2000
4000
10
8000
BAND CENTER FREQUENCIES, Hz
MSC-GE35VB
Test conditions.
Cooling : Dry-bulb temperature 27
Heating : Dry-bulb temperature 20
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
90
COOLING
40
HEATING
39
LINE
Wet-bulb temperature 19
Wet-bulb temperature -
80
70
NC-70
60
NC-60
50
NC-50
40
NC-40
30
NC-30
20
NC-20
NC-10
63
125
250
500
1000
2000
4000
8000
BAND CENTER FREQUENCIES, Hz
OBH529A
NC-10
63
125
250
500
1000
2000
BAND CENTER FREQUENCIES, Hz
SPL(dB(A))
FAN SPEED FUNCTION
High
10
LINE
5
4000
8000
MS-GE50VB
FAN SPEED FUNCTION
High
SPL(dB(A))
COOLING
MSH-GE50VB
LINE
Test conditions,
Cooling : Dry-bulb temperature 27
Heating : Dry-bulb temperature 20
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
80
70
NC-70
60
NC-60
50
NC-50
40
NC-40
30
NC-30
20
NC-20
NC-10
63
125
250
500
1000
2000
4000
8000
INDOOR UNIT
WALL
1m
0.8m
MICROPHONE
6
LINE
42
HEATING
Wet-bulb temperature 19
Wet-bulb temperature -
80
70
NC-70
60
NC-60
50
NC-50
40
NC-40
30
NC-30
20
NC-20
10
NC-10
63
125
250
500
1000
2000
4000
BAND CENTER FREQUENCIES, Hz
BAND CENTER FREQUENCIES, Hz
OBH529A
SPL(dB(A))
COOLING
High
Test conditions,
Cooling : Dry-bulb temperature 27°C Wet-bulb temperature 19°C
90
10
FAN SPEED FUNCTION
42
8000
OUTLINES AND DIMENSIONS
133.5
Installation plate
Indoor unit
Unit: mm
4.5
81.5
271
MSC-GE20VB
MSC-GE25VB
231.5
5
81.5
326
42
41
2.5
783
81.5
326
Wall hole
Air in
242
5
Installation plate
{
278
7 or more
815
58
90
30
149
606
60
19
110
Air out
162
Power supply cord
Lead to right 1.0m
Lead to left 0.3m
65
244
Liquid line 6.35-0.5m
Gas line 9.52-0.43m
Insulation 37 O.D
21 I.D
Drain hose 16
(Connected part O,D)
Insulation 28
Wireless remote controller
MSC-GE35VB
Indoor unit
2.5
41
783
326
81.5
326
42
218.5
Installation plate
81.5
Wall hole
Air in
242
5
{
278
30
19
162
58
90
149
606
60
Air out
Power supply cord
Lead to right 1.0m
Lead to left 0.3m
Wireless remote controller
OBH529A
7
110
244
65
Installation plate
7 or more
815
258
161.5
17.5
Unit: mm
161.5
Liquid line 6.35-0.5m
Gas line 9.52-0.43m
Insulation 37 O.D
21 I.D
Drain hose 16
(Connected part O,D)
Insulation 28
Installation plate
Unit: mm
Indoor unit
98
7.5
173
98
414.5
414.5
Wall hole
258
1100
Air in
173
Installation plate
325
791
253
Air out
19
162
58
Power supply cord
Lead to right 2.0 m
Lead to left 1.0 m
Wireless remote controller
OBH529A
8
47
75
5
{
56
2.5
47
255.5
1068
315
MS-GE50VB
MSH-GE50VB
Liquid line 6.35- 0.5 m
Gas line 12-0.43 m
Insulation 50 O.D
32 I.D
Drain hose 16
(Connected part O.D)
Insulation
28
6
WIRING DIAGRAM
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
MS-GE50VB
MSH-GE50VB
OBH529A
9
7
REFRIGERANT SYSTEM DIAGRAM
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
Refrigerant pipe 9.52
(with heat insulator)
Indoor
heat
exchanger
Indoor coil
thermistor
RT12
Unit:mm
Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant pipe 6.35
(with heat insulator)
MS-GE50VB
MSH-GE50VB
Refrigerant pipe 12.7
(with heat insulator)
Indoor
heat
exchanger
Indoor coil
thermistor
RT12
Distributor
Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant pipe 6.35
(with heat insulator)
Refrigerant flow in cooling
Refrigerant flow in heating (MSC,MSH)
OBH529A
10
SERVICE FUNCTIONS
8
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
MS-GE50VB
MSH-GE50VB
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. (Refer to 10-6.)
The time will be shortened as follows.
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:
NOTE: For modification, take out the batteries and press the OPERATE/STOP (ON/OFF) button 2 or 3 times at first.
After modification, put back the batteries then press the RESET button.
J1
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.
Table 1
1 unit operation
2 units operation
3 units operation
4 units operation
No. 1 unit
No modification
Same as at left
Same as at left
Same as at left
No. 2 unit
–
Solder J1
Same as at left
Same as at left
No. 3 unit
–
–
Solder J2
Same as at left
No. 4 unit
–
–
–
Solder both J1 and J2
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 accept 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.
8-3. REMOTE CONTROLLER (How to set the type) MSC-GE
This remote controller setting needs to be switched according to the type of air conditioner (COOL & HEAT or COOL
ONLY).
If the setting is incorrect, the air conditioner does not operate normally. Therefore, check if the setting corresponds to the
type of-air conditioner. If not, correct the setting as shown below.
Slide switch
Type
The position
of the slide
switch
OBH529A
11
COOL & HEAT COOL ONLY
8-4. MU & MUX TYPE/MUH & MXZ TYPE SWITCH OVER AND AUTO RESTART FUNCTION
1. MU & MUX TYPE/MUH & MXZ TYPE SWITCH OVER
<MSC-GE20VB MSC-GE25VB MSC-GE35VB>
The indoor units for MU & MUX type and MUH & MXZ type
are common specifications. Set switch according to the type
of outdoor unit. The units are set for
MUH & MXZ type when they are shipped from the factory.
SW2SW2-
sets the AUTO RESTART FUNCTION ON/OFF.
switches over the MU & MUX type/MUH & MXZ type.
When the units are shipped from the factory, SW2 is as follows.
SW2- : AUTO RESTART FUNCTION ON
SW2- : MUH & MXZ type
}
F11
1
C1
L101
1
21
N
C
LD105
CN202
IC101
1 2
SW2
SW1
1 2
SW2
SW2
CN151
Outdoor unit
MUH & MXZ type
Set switch downside.
SW2
Outdoor unit
MU & MUX type
Set switch upside.
FRONT
1 2
1 2
CN121 CN112
CN201
How to switch over MU & MUX TYPE/MUH & MXZ TYPE
(1) Turn OFF the main power for the unit.
(2) Pull out the electronic control P.C. board, and change
switch (SW2- ) on the indoor electronic control P.C. board
according to the type of outdoor unit as following figures.
(Refer to 10-6.)
<MSC-GE20VB MSC-GE25VB MSC-GE35VB>
NOTE: • If the indoor-outdoor connecting wire is incorrectly
connected on the terminal block, the unit does not
operate normally.
• If the earth is incorrect, it may cause an electric
shock.
2. 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. “AUTO RESTART FUNCTION” automatically starts operation in the same mode just before the shutoff of the main power. 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
If the main power has been cut, the operation settings
remain.
After 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 disable “AUTO RESTART FUNCTION”
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
(1) Turn OFF the main power for the unit.
(2) Pull out the electronic control P.C. board, and change
switch (SW2- ) on the indoor electronic control P.C.
board as following figures. (Refer to 10-6.)
AUTO RESTART
FUNCTION ON
Set switch downside.
1 2
SW2
OBH529A
AUTO RESTART
FUNCTION OFF
Set switch upside.
1 2
SW2
12
MS-GE50VB
MSH-GE50VB
(1) Turn OFF the main power for the unit.
(2) Solder jumper wire to JR07 on the indoor electronic control
P.C. board. (Refer to 10-6.)
<MS-GE50VB MSH-GE50VB>
NOTE:
•The operation settings are memorized when 10 seconds have passed after the indoor unit 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.
OBH529A
13
9
MICROPROCESSOR CONTROL
WIRELESS REMOTE CONTROLLER
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
Signal transmitting section
Operation display section
PM
OPERATE /STOP
(ON /OFF) button
AM
TOO
WARM
ON/OFF
TOO
COOL
TEMPERATURE buttons
CLOCK
PM
AM
TOO
WARM
ON/OFF
FAN SPEED CONTROL button
TOO
COOL
FAN
STOP
I FEEL COOL
HEAT
/FAN
VANE
START
DRY
/
HR.
MODE
OPERATION SELECT button
ECONO COOL
ECONO COOL button
MIN.
RESET CLOCK
OFF-TIMER button
ON-TIMER button
HR. button
MIN. button
(TIME SET button)
CLOCK SET button
VANE CONTROL button
RESET button
MS-GE50VB
Signal transmitting section
Operation display section
PM
OPERATE/ STOP
(ON/ OFF) button
AM
ON/OFF
TOO
WARM
TOO
COOL
TEMPERATURE buttons
CLOCK
PM
AM
ON/OFF
VANE button
(Horizontal vane button)
TOO
WARM
TOO
COOL
FAN
STOP
VANE
START
I FEEL COOL
FAN
DRY
OFF-TIMER button
ON-TIMER button
MODE
WIDE VANE
HR.
ECONO COOL
LONG
MIN.
OPERATION SELECT button
ECONO COOL button
RESET CLOCK
WIDE VANE button
(Vertical vane button)
FAN SPEED CONTROL button
HR. button
MIN. button
(TIME SET button)
CLOCK SET button
LONG button
RESET button
OBH529A
14
MSH-GE50VB
Signal transmitting section
Operation display section
PM
OPERATE/STOP
(ON/OFF) button
AM
ON/OFF
TOO
WARM
TOO
COOL
TEMPERATURE buttons
CLOCK
PM
AM
ON/OFF
VANE button
(Horizontal vane button)
TOO
WARM
TOO
COOL
FAN
STOP
VANE
START
FAN SPEED CONTROL button
I FEEL COOL
HEAT DRY
OFF-TIMER button
ON-TIMER button
MODE
WIDE VANE
HR.
ECONO COOL
LONG
MIN.
HR. button
MIN. button
(TIME SET button)
OPERATION SELECT button
ECONO COOL button
RESET CLOCK
CLOCK SET button
WIDE VANE button
(Vertical vane button)
LONG button
RESET button
NOTE:
• The last setting will be stored after the unit is turned OFF with the remote controller.
• Indoor unit receives the signal of the remote controller with beeps.
INDOOR UNIT DISPLAY SECTION
OPERATION INDICATOR lamp
The OPERATION INDICATOR at the right side of the indoor
unit indicates the operation state.
Indication
The following indication applies regardless of
shape of the indicator.
Lighted
Not lighted
OBH529A
15
Operation state
Difference
between target
temperature
and room
temperature
This shows that the
air conditioner is
operating to reach
the target temperature.
Please wait until the
target temperature is
obtained.
Approx. 2
or more
This shows that the
room temperature is
approaching the
target temperature.
Approx. 2
or less
9-1. COOL ( ) OPERATION
ON with a beep tone.
1. Coil frost prevention
When the temperature of indoor heat exchanger becomes too low, the coil frost prevention mode works.
The indoor fan operates at the set speed and the compressor stops. This mode continues until the temperature of indoor
heat exchanger rises.
9-2. DRY ( ) OPERATION
The set temperature is determined from the initial room temperature.
<MU,MUX,MUH>
However, when the coil frost prevention works while the indoor fan is OFF, the indoor fan speed becomes set speed.
9-3. FAN( ) OPERATION <MU/MUX>
(1) Press OPERATE/STOP (ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns ON with a beep tone.
(2) Select FAN mode with OPERATION SELECT button.
(3) Select the desired fan speed. When AUTO, it becomes Low.
Only indoor fan operates.
Outdoor unit does not operate.
9-4. HEAT ( ) OPERATION <MUH>
Cold air prevention control
When the compressor is not operating or is starting, and the temperature of indoor heat exchanger and/or the room
temperature is low or when defrosting is being done, the indoor fan will stop or rotate in Very Low speed.
2.
Defrosting starts when the temperature of outdoor heat exchanger becomes too low.
The compressor stops once, the indoor/outdoor fans stop, the 4-way valve reverses, and the compressor re-starts.
This mode continues until the temperature of outdoor heat exchanger rises or the fixed time passes.
9-5."I FEEL CONTROL" (
) OPERATION
(1) Press OPERATE/STOP (ON/OFF) button on the remote controller.
OPERATION INDICATOR lamp of the indoor unit turns ON with a beep tone.
(2) Select "I FEEL CONTROL" mode with OPERATION SELECT button.
(3) The operation mode is determined by the room temperature at start-up of the operation.
Initial room temperature
Mode
25
or more
COOL mode of
"I FEEL CONTROL"
23
to 25
DRY mode of
"I FEEL CONTROL"
<MUH>
Less than 23
OBH529A
HEAT mode of
"I FEEL CONTROL"
16
<MUH>
<MUH>
OBH529A
17
9-6. AUTO VANE OPERATION
CONTROL or VANE
To confirm the standard position, the vane moves until it touches the vane stopper. Then the vane is set to the desired angle.
in the following case:
In FAN operation
<MU,MUX>
<MUH>
VANE CONTROL or VANE
VANE CONTROL or VANE
<MUH>
The horizontal vane position is set to Upward.
OBH529A
18
When ECONO COOL button is pressed in COOL mode, set temperature is automatically set 2 C higher.
Also the horizontal vane swings in various cycles.
SWING operation makes you feel cooler than set temperature. So, even though the set temperature is higher, the air
conditioner can keep comfort. As a result, energy can be saved.
To cancel this operation, select a different mode or press one of the following buttons in ECONO COOL operation:
ECONO COOL, VANE CONTROL, VANE or LONG button.
<MS-GE50 / MSH-GE50>
To cancel this operation, press one of the following buttons:
ECONO COOL button in COOL mode, VANE or LONG button.
<MS-GE50 / MSH-GE50>
To confirm the standard position, the vane moves until it touches the vane stopper. Then the vane is set to the desired angle.
in the following case:
<MSH>
OBH529A
19
<MSH>
9-7. TIMER OPERATION
OBH529A
20
9-8. EMERGENCY/TEST OPERATION
The indoor fan runs at High speed and the temperature control does not work.
/(HEAT MODE <MUH>) with a set
temperature of 24 °C.
(and defrosting also <MUH>).
the test run or the
(or twice <MUH>) or the unit
receives any signal from the remote controller. In case of latter, normal operation will start.
*Heat is a vailable only in MUH.
9-9. 3-MINUTE TIME DELAY OPERATION
When the system turns OFF, compressor will not restart for 3 minutes as 3-minute time delay function operates to protect
compressor form overload.
OBH529A
21
10
TROUBLESHOOTING
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
MS-GE50VB
MSH-GE50VB
10-1. 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 after confirming 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
components.
(4) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
<Correct>
<Incorrect>
Lead wiring
Housing point
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 OPERATION INDICATOR lamp is flashing ON and OFF before starting service work.
(2) Before servicing, check that the connector and terminal are connected properly.
(3) When the electronic control P.C. board seems to be defective, check the copper foil pattern for disconnection and the
components for bursting and discoloration.
(4) When troubleshooting, refer to 10-2. and 10-3.
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.
Press RESET button with a thin instrument, and
Remove the front lid and insert batteries.
then use the remote controller.
Then reattach the front lid.
Insert the negative pole
of the batteries first.
Check if the polarity of
the batteries is correct.
RESET button
NOTE1: If the RESET button is not pressed, the remote controller may not operate correctly.
NOTE2 : INFORMATION FOR MULTI SYSTEM AIR CONDITIONER
(OUTDOOR UNIT : MXZ type)
Multi system air conditioner can connect two or more indoor units with one outdoor unit.
According to the capacity, two or more units can operate simultaneously.
•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 cannot operate, indicating as shown in the figure below. In this case, please set all the indoor units to the same operation mode.
Operation Indicator
Lighted
Flashing
•When indoor units start 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.
NOTE3 : This remote controller has a circuit to automatically reset the microcomputer when batteries are replaced.
This function is equipped to prevent the microcomputer from malfunctioning due to the voltage drop caused by the
battery replacement.
NOTE4 : Do not use the leaking batteries.
OBH529A
22
10-2. INSTRUCTION OF TROUBLESHOOTING
Start
Indoor unit
operates.
Outdoor unit
does not
operate.
Indoor unit
does not receive
the signal from
remote controller.
Indoor unit
operates.
Outdoor unit
does not operate
normally.
OPERATION INDICATOR
lamp on the indoor unit is
flashing ON and OFF.
Outdoor unit
operates only
in “Test run
operation”.
MUH/MUX
Outdoor unit
does not
operate
even in
“Test run
operation”.
Outdoor unit
does not
stop even
if indoor unit
stops.
MUH/MXZ
Unit does not
operate
normal
operation in
COOL or
HEAT mode.
Indoor unit
operates, when
the EMERGENCY
OPERATION
switch is pressed.
Indoor unit
does not operate,
when the
EMERGENCY
OPERATION
switch is pressed.
Check room
temperature
thermistor.
Refer to 10-6.
"Test point
diagram and
voltage".
Refer to
"Check of
outdoor unit".
MU
Check of wiring
diagram of
outdoor unit
MUH
Refer to
"Check of
outdoor unit".
Refer to
"Check of
R.V. coil".
Refer to 10-5.
"Check of
remote controller
and receiver
P.C. board".
1. Check indoor/
outdoor
connecting wire.
2. Refer to 10-5.
"Check of indoor
electronic control
P.C. board".
MUH/MXZ
2-time flash
Flash ON and
Cause:
OFF at 0.5Indoor unit
second intervals
• Trouble of
Cause: Indoor/
room tempoutdoor unit
erature/
• Mis-wiring/or
indoor coil
trouble of
serial signal
thermistor
Refer to
10-5. or
"How to
check
mis-wiring/
and serial
signal error
(When
outdoor unit
does not
work)".
Check room
temperature
thermistor
and indoor
coil thermistor.
Refer to 10-6.
"Test point
diagram and
voltage".
3-time flash
Cause:
Indoor unit
• Trouble of
indoor fan
motor
Refer to
10-5.
"Check of
indoor fan
motor".
4-time flash
Cause:
Indoor unit
• Trouble of
indoor unit
control
system
Replace the
indoor
electronic
control
P.C. board.
MXZ
5-time flash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality
Refer to
"Check of
inverter/
compressor"
and "Check
of power
supply".
MUH/MXZ
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
MUH/MXZ
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Refer to
"Check of
outdoor
thermistor"
and others.
Replace the
deicer
P.C. board
and others.
MUX-2A28/2A59/3A60/
3A63/2A70/4A73VB
Refer to
"Check of
indoor/outdoor
units' connection
and outdoor
unit".
10-time flash
Cause:
Outdoor unit
MXZ
• Outdoor
refrigerant
system
abnormality
Refer to
outdoor
refrigerant
system
related items.
1.<The case of the trouble of the serial signal>
When the power is turned off and turned on again, the indication shows “the trouble of mis-wiring”.
2."Test run operation" means the operation within 30 minutes after EMERGENCY OPERATION switch is pressed.
Refer to outdoor unit service manual.
OBH529A
23
Indoor unit
operates.
But indoor
unit does not
blow out
cool air.
10-3. TROUBLESHOOTING CHECK TABLE
• Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
When the indoor unit has started operation and the following detection method has detected an abnormality
(the first detection after the power ON), the indoor electronic control P.C. board turns OFF the indoor fan motor
with the OPERATION INDICATOR lamp flashing.
· Flashing of the OPERATION INDICATOR lamp (the left-hand side lamp)
Lighted
indicates possible abnormalities.
Not lighted
No.
1
Abnormal
point
Operation indicator lamp
MUH-GA/ 0.5-second ON
MXZ
Mis-wiring/
or Serial
signal
0.5-second OFF
MUH-GE
Mis-Wiring
0.5-second ON
0.5-second OFF
Indoor coil
thermistor
2
Room
temperature
thermistor
2-time flash
Remedy
Outdoor unit
does not run.
Serial signal from outdoor unit stops for 4 to 5
seconds.
Outdoor unit
does not
operate.
3 minutes after power supply turns ON,
serial signal is not received.
• Refer to 10-5. E "How to
check mis-wiring ".
Indoor coil/room temperature thermistor
detects short or open circuit every 8 seconds
during operation.
• Refer to the characteristics
of indoor coil thermistor, and
room temperature thermistor
on 10-6.
2.5-second OFF
Indoor fan
motor
2.5-second OFF
4-time flash
Indoor
4 control
system
Condition
• Check switch SW2- .(MU &
MUX type or MUH & MXZ
type)
• Check wiring (visual check
and conductivity check).
• Check indoor electronic
control P.C.board.
• Check outdoor DEICER P.C.
board and others.
• Check electrical parts.
Outdoor unit
does not
operate.
3-time flash
3
Symptom
Indoor fan repeats
The rotational frequency feedback signal is
12 seconds ON
and 3minutes OFF. not emitted for 12 seconds after indoor fan
motor is operated.
When the indoor
fan breaks, the fan
keeps stopping.
Outdoor unit
does not
operate.
It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.
• Refer to 10-5. "Check of
indoor fan motor".
• Check the indoor electronic
control P.C. board.
2.5-second OFF
5
6
7
8
5-time flash
MXZ
Outdoor
power
system
Outdoor unit
does not run.
2.5-second OFF
MUH/
MXZ
Outdoor
thermistor
2.5-second OFF
Outdoor unit
does not
operate.
7-time flash
MUH/
MXZ
Outdoor
control
system
2.5-second OFF
MXZ
Outdoor
refrigerant
system
error
MXZ
Operation
9 mode
setting
6-time flash
Outdoor unit
does not
operate.
The compressor operation is
continuously three times interrupted by over
current protection within 1 minute after
start-up , it stops operation.
<Thermistor short>
Thermistors are abnormal when they short
after compressor start-up.
<Thermistor open>
Thermistors are abnormal when they open
after compressor start-up.
However, discharge temperature thermistor is
abnormal when open circuit is detected more
than 10 minutes after compressor start-up.
• Shortage of refrigerant
• Check the deicer P.C. board
and others.
Refer to "Check of outdoor
thermistor". Refer to outdoor
service manual.
It cannot properly read data in the nonvolatile
memory of the outdoor P.C. board.
• Check the deicer P.C. board
and others.
Refer to outdoor service
manual.
Outdoor unit
does not run.
The compressor operation has been
interrupted by LEV protection continuously 5
minutes, the compressor stops operation.
• Refer to "Check of LEV".
• Check refrigerant circuit and
refrigerant amount.
• Check outdoor electronic
control P.C. board.
Refer to outdoor unit service
manual.
Outdoor unit
operates but
indoor unit
does not run.
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.
10-time flash
2.5-second OFF
Operation Indicator
Lighted
Flashing
2.5-second OFF
OBH529A
• Check the inverter output.
• Check the compressor.
24
10-4. TROUBLE CRITERION OF MAIN PARTS
Part name
MS-GE50VB
MSH-GE50VB
Room temperature
thermistor (RT11)
Check method and criterion
Measure the resistance with a tester.
(Part temperature 10°C ~ 30°C)
Figure
Indoor coil thermistor
(RT12)
Refer to 10-6. "Test point diagram and voltage",
"Indoor electronic control P.C. board", for the chart of thermistor.
MSC-GE20/25/35VB
INNER FUSE
145°C CUT OFF
MS-GE50VB
MSH-GE50VB
INNER FUSE
140°C CUT OFF
Vane motor (MV)
Horizontal vane
motor (MV1)
Vertical vane
motor (MV2)
WHT
RED
Color of
lead wire
MSC-GE20/25VB
MSC-GE35VB
WHT – BLK
BLK – RED
271 Ω ~ 295 Ω
180 Ω ~ 196 Ω
215 Ω ~ 233 Ω
305 Ω ~ 331 Ω
Color of lead wire
BRN – YLW
YLW – GRY
MS-GE50VB
MSH-GE50VB
284 Ω ~ 307 Ω
142 Ω ~ 154 Ω
FUSE
BLK
YLW
GRY
BRN
MS-GE50VB
MSH-GE50VB
Normal
4.5 ~ 5.5V
(When fan revolved one time)
0V 5V 0V
(Approx.)
Measure the resistance between the terminal with a tester.
(Part temperature 10°C ~ 30°C)
Normal
MS-GE50VB
MSH-GE50VB
283 Ω ~ 306 Ω
MSC-GE20/25/35VB
240 Ω ~ 260 Ω
OBH529A
MSC-GE20/25/35VB
Normal
Measure the voltage power ON.
Sensor part
Indoor fan motor (MF)
Motor part
Measure the resistance between the terminals with a tester.
(Part temperature 10°C ~ 30°C)
25
MAIN
AUX
FUSE
BLK
BRN
YLW
GRY
RED
WHT
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
RED
ROTOR
YLW
BRN
ORN
GRN
10-5. TROUBLESHOOTING FLOW
When OPERATION INDICATOR lamp flashes 3-time. Indoor fan motor does not operate.
A Check of indoor fan motor
Turn OFF the power supply.
Check connector CN211 visually.
No
Are lead wires connected?
Yes
No
Is soldered point of the connector
correctly soldered?
Resolder it.
Yes
Reconnect the lead wires.
Disconnect lead wires from connector CN211 on the indoor electronic control P.C. board.
Measure resistance between lead wires No.1 and No.5 and then No.3 and No.5 (MSC-GE20/25/35VB)/
No.3 and No.4 and then No.1 and No.4 (MS-GE50VB, MSH-GE50VB).
Is resistance 0 (short circuit) or
(open circuit)?
Yes ( 0 or
)
No
(others)
Repair or replace the indoor fan motor.
Turn ON the power supply. Stop it if the unit operate.
Insert screwdriver into air outlet to rotate indoor fan
motor slowly for 1 revolution or over, and measure
voltage between No.2(+) and No.3(-) on CN121.
No
Does voltage repeat 0 V DC and 5 V DC?
Yes
Replace the indoor electronic control P.C. board.
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote controller.
B Check of remote controller and receiver P.C. board
Check if the remote controller is exclusive for this air conditioner.
Press OPERATE/STOP (ON/OFF)
button on the remote controller.
No
Is LCD display on the remote controller visible?
Replace the batteries (Refer to 10-1.4.).
(not clear)
Yes
Remove the batteries, then set them back
and press the RESET button. Check if the
unit operates with the remote controller.
Does the unit operate with the
remote controller?
No
Turn ON a radio to AM and press
OPERATE/STOP (ON/OFF) button on the
remote controller.
Yes
OK
Is noise heard from radio?
No
Replace the remote controller.
Yes
Are there any fluorescent lights of
inverter or rapid-start type within
the range of 1 m?
Yes
Reinstall the unit away from lights.
Attach a filter on receiving part.
No
Measure the voltage between receiver P.C. board connector CN302 No.3(-) and No.5(+) (MSC-GE20/
25/35VB)/CN301 No.1(+) and No.3(-) (MS-GE50VB, MSH-GE50VB) when the remote controller button is
pressed (Refer to 10-6.).
Is the voltage approximately 4 V DC?
Yes
No (5 V or 0 V DC)
Replace the power monitor, receiver P.C board or the receiver P.C. board.
OBH529A
26
Replace the indoor electronic control P.C.
board.
The unit does not operate with the remote controller. Also, the OPERATION INDICATOR lamp does not light up by
pressing the EMERGENCY OPERATION switch.
C Check of indoor electronic control P.C. board
Check the both “parts side” and “pattern
side” of indoor electronic control P.C.
board visually.
Varistor (NR11)
Turn OFF the power supply.
Remove indoor fan motor connector CN211 and
vane motor connector CN151 from the indoor electronic
control P.C. board and turn ON the power supply.
Indoor electronic
control P.C. board
Does the unit operate with the remote controller?
No
Does the OPERATION INDICATOR lamp light up
by pressing the EMERGENCY OPERATION switch?
Yes
Turn OFF the
power supply.
Replace the vane
motor.
Turn OFF the
power supply.
Yes
Replace the fuse.
Yes
Is winding
resistance of
vane motor 0 Ω?
Is fuse (F11) blown?
No
No
Is winding
resistance of
fan motor 0 Ω?
No
Is varistor (NR11) burnt?
Yes
Yes
Replace the fan
motor.
OBH529A
Replace the varistor.
27
No
Replace the indoor
electronic control
P.C. board.
When OPERATION INDICATOR lamp flashes 0.5-second intervals or 1-time.
Outdoor unit does not operate.
How to check mis-wiring and serial signal error
MUH (Except MUH-GE50VB), MXZ
1 Set the switch(SW2- ) on indoor electronic control P.C. board to
MU or MUX type, when the outdoor unit is MU or MUX type.
If the setting is MUH or MXZ type, the unit does not work.
Start
2 Short circuit of JPG and JPS on the indoor electronic control
P.C. board enables self-check to be displayed in 3 seconds.
Turn OFF the power supply(indoor/outdoor unit).
Is the outdoor unit "MUH" or “MXZ” type?
Yes
Set the switch(SW2- ) on the indoor electronic
control P.C. board to MU or MUX type. 1
No
•Turn ON the power supply(indoor/outdoor unit).
•Press once EMERGENCY OPERATION switch.
•3 min. later, check the self-check result
displayed on OPERATION INDICATOR
lamp on indoor unit. 2
Does the unit operate?
No
Refer to the
"Instruction of
troubleshooting."
Serial signal error is indicated.
(0.5-sec. ON, 0.5-sec. OFF)
Yes
Correct them.
Is this mis-wiring, poor contact,
or disconnection of wire?
No
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 and .
3. Turn ON the power supply(indoor unit) and press once EMERGENCY OPERATION switch.
Is there 20V DC between both ends of
R132 on indoor electronic control P.C.
board ?
( By tester, the stylus is between 0 ~ 20V. )
No
Replace the indoor electronic
control P.C. board.
Yes
•Turn OFF the power supply(indoor unit).
•Connect indoor and outdoor connecting wire.
Turn ON the power supply(outdoor unit).
Is there 230V AC between outdoor terminal
block
(TB1)?
No
Yes
Is there 5V DC between J205 + –J101 - on the deicer P.C. board?
Check the outdoor power supply,
power supply cord and
connection.
No
Replace the deicer P.C. board.
Yes
Turn ON the power supply(indoor unit).
During EMERGENCY OPERATION,
is there 10V DC between both ends
of R601?
(By tester, the stylus is between 5 ~10V)
Yes
Replace the deicer P.C. board.
Refer to outdoor unit service manual.
OBH529A
28
No
Correct the wiring between
CN730 on the deicer P.C. board
and outdoor terminal block.
Yes
OK
When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second.
Outdoor unit does not operate.
E How to check mis-wiring
MUH-GE50VB
Short circuit of JPG and JPS on the indoor electronic control
P.C. board enables self -check to be displayed in 3 seconds.
Start
• Turn ON the power supply. (indoor/outdoor unit)
• Press EMERGENCY OPERATION switch once.
After 3 minutes, mis-wiring is indicated
(0.5-second ON, 0.5-second OFF)
on OPERATION INDICATOR
lamp on indoor unit.
Yes
Correct them.
Is this mis-wiring, poor contact,
or wire disconnection?
No
1. Turn OFF the power supply (indoor/outdoor unit) and disconnect indoor and outdoor
connecting wire on indoor side.
2. Short-circuit terminal block N - 3 by lead wire.
3. Turn ON the power supply (indoor unit) and press EMERGENCY OPERATION switch once.
Is there 20 V DC between both ends of
R132 on the indoor electronic control P.C.
board ?
( By tester, the stylus is between 0 ~ 20 V. )
No
Replace the indoor electronic
control P.C. board.
Yes
• Turn OFF the power supply. (indoor unit)
• Connect indoor/outdoor connecting
wire.
Turn ON the power supply(outdoor unit).
No
Is there 230 V AC between outdoor terminal
block
(TB1)?
Check the outdoor power supply
and connection of wiring .
Yes
Is there 5 V DC between J205 + –J101 - on the deicer P.C. board?
No
Replace the deicer P.C. board.
Yes
Turn ON the power supply(indoor unit).
During EMERGENCY OPERATION,
is there 10 V DC between both ends
of R601?
(By tester, the stylus is between 5 ~10 V)
Yes
No
Replace the deicer P.C. board.
Refer to outdoor unit service manual.
OBH529A
29
Make the wiring between CN730
on the deicer P.C. board and
outdoor terminal block correct.
10-6. TEST POINT DIAGRAM AND VOLTAGE
Fuse (F11)T3.15AL 250V
Power supply input
230 V AC
}
MSC-GE20VB
MSC-GE25VB
MSC-GE35VB
Indoor electronic control P.C. board
R132
Fan motor
power supply
(CN211)
Safety device of
fan by horizontal
vane CN1R1
Room temperature
thermistor RT11
Indoor coil
thermistor
RT12
Varistor
(NR11)
J12
12 V
DC
}
{ –+
J33
Timer short mode
point JPG, JPS
(Refer to 8-1.)
Emergency
operation switch
–+
J23
CN121
}
Power monitor,
receiver P.C. board
J33
5 V DC
Vane moter
power supply
(CN151)
SW2
(Refer to 8-4.)
sets the "Auto restart
function" ON/OFF.
switches over
MU & MUX type/
MUH & MXZ type.
Resistance (k )
Indoor coil thermistor (RT12)
Room temperature thermistor (RT11)
CN302
Temperature ( )
OBH529A
30
MS-GE50VB
MSH-GE50VB
Indoor electronic control P.C. board
NOTE: There are two types of electronic control P.C.
boards (TYPE 1/TYPE 2). They are both compatible
with MS/MSH-GE50VB.
TYPE 1
Fan motor power supply
(CN211)
}
Power supply input
230 V AC
+
} 5 V DC
Room temperature
thermistor (RT11)
Indoor coil
thermistor (RT12)
Fuse (F11)
T3.15AL250V
R132
CN121
Vane moter
power supply
(CN151)
Emergency operation
switch
Timer short mode point
(JPS, JPG)
(Refer to 8-1.)
+
}
Receiver P.C. board
12V DC
CN301
OBH529A
To disable “Auto restart function”,
solder jumper wire to JR07.
(Refer to 8-4.2.)
31
Resistance(kΩ)
Indoor coil thermistor (RT12)
Room temperature thermistor (RT11)
MS-GE50VB
MSH-GE50VB
Indoor electronic control P.C. board
TYPE 2
Fan motor power supply
(CN211)
}
Power supply input
230 V AC
+
Fuse (F11)
T3.15AL250V
} 5 VDC
R132
Room temperature
thermistor (RT11)
Indoor coil
thermistor (RT12)
12 VDC
{
+
CN121
Vane motor
power supply
(CN151)
To disable “Auto restart
function”, solder jumper
wire to JR07.
(Refer to 8-4.2.)
Emergency
operation
switch
Timer short
mode point
(JPS, JPG)
(Refer to 8-1.)
Indoor coil thermistor (RT12)
Room temperature thermistor (RT11)
Resistance(k )
Receiver P.C. board
CN301
OBH529A
32
11
DISASSEMBLY INSTRUCTIONS
<"Terminal with locking mechanism" Detaching points>
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.
(1) Slide the sleeve and check if there is a locking lever or not.
Sleeve
Slide the sleeve.
Pull the terminal while
pushing the locking
lever.
Locking lever
11-1. MSC-GE20VB
(2) The terminal with this connector has the locking
mechanism.
MSC-GE25VB
Hold the sleeve, and
pull out the terminal
slowly.
Connector
MSC-GE35VB
NOTE: Turn OFF power supply before disassembly.
OPERATING PROCEDURE
PHOTOS
1. Removing the front panel
(1) Remove the screw caps of the front panel.
Remove the screws.
(2) Pull the panel down to your side slightly and unhook the
catches at the top.
Photo 1
Screws of the front panel
2. Removing the electronic control P.C. board and the
power monitor, receiver P.C. board
NOTE : In case of removing only indoor electronic control
P.C. board, work (3) is not necessary.
(1) Remove the front panel. (Refer to 1.)
(2) Remove the power monitor, receiver P.C. board holder
from the bottom of electrical box.
(3) Open the power monitor, receiver P.C. board holder and
remove the power monitor, receiver P.C. board.
(4) Remove the screw of the electrical cover and the electrical
cover.
(5) Remove the screw of the V.A. clamp and the V.A. clamp.
(6) Remove the screw of the cord clamp and the cord clamp.
(7) Remove the screw of the terminal block.
(8) Remove the screw of the earth wire.
(9) Pull out indoor electronic control P.C. board slightly.
(10) Disconnect all the connectors on the electronic control P.C.
board.
(11) Remove the electronic control P.C. board and the power
monitor, receiver P.C. board.
Photo 2
Terminal block
fixing screw
Screw of the
earth wire
Cord clamp fixing
screw
Screw of the V.A.
clamp
Screw of the
electrical cover
Power monitor, receiver
P.C. board holder
OBH529A
33
Indoor electronic
control P.C. board
OPERATING PROCEDURE
PHOTOS
3. Removing the electrical box
(1)
(2)
(3)
(4)
(5)
(6)
(7)
Remove the front panel. (Refer to 1.)
Remove the electrical cover. (Refer to 2.)
Remove the V.A. clamp. (Refer to 2.)
Remove the cord clamp. (Refer to 2.)
Remove the terminal block. (Refer to 2.)
Remove the screw of earth wire. (Refer to 2.)
Disconnect the connector of the indoor coil thermistor
(CN112), the fan motor connector (CN211 and CN121) and
the vane motor connector (CN151) on the electronic control
P.C. board.
(8) Remove the fan motor lead wire and indoor coil thermistor
from the electrical box.
(9) Remove the lead wire of vane motor from the bottom of
electrical box.
(10) Remove the screw fixing the electrical box, remove the
electrical box.
4. Removing the nozzle assembly and the vane motor
Photo 3
Indoor coil thermistor
connector
Vane motor
connector
Screw of the
electrical box
Fan motor connector
Photo 4
(1) Remove the front pane and the corner box. (Refer to 1.)
(2) Remove the electrical box. (Refer to 3.)
(3) Pull out the drain hose from the nozzle assembly, remove
the nozzle assembly.
(4) Remove the screws of the vane motor, disconnect the
vane motor connector.
(5) Remove the vane motor.
Screws of the vane motor
Drain hose
5. Removing the indoor fan motor and the line flow fan
(1) Remove the front panel the corner box. (Refer to 1.)
(2) Remove the electrical box. (Refer to 3.)
(3) Pull out the drain hose from the nozzle assembly, remove
the nozzle assembly. (Refer to 4.)
(4) Remove the screw of the lead cover and lead cover.
(5) Release the hooks to open the motor band slightly.
(6) Loosen the hexagon socket set screw from the line flow
fan.
(7) Remove the screws fixing the motor bed, remove the fan
motor with motor band and the motor bed.
(8) Remove the screws fixing the left side of the heat
exchanger.
(9) Lift the left side of the heat exchanger.
(10) Remove the line flow fan.
Photo 6
Photo 5
Screws of the left
side of the heat
exchanger
Photo 7
Hexagon socket set screw
Screw of
the lead
cover
OBH529A
Hooks of the
motor band
34
Screws of
the motor
bed
11-2. MS-GE50VB
MSH-GE50VB
NOTE: Turn OFF power supply before disassembly.
OPERATING PROCEDURE
PHOTOS
1. Removing the panel
(1) Remove the screw caps of the panel.
Remove the screws of the panel.
(2) Pull the panel down to your side slightly and unhook the
catches at the top.
(3) Remove the screw of the corner box.
Remove the corner box.
Photo 1
Screws of the panel
2. Removing the electronic control P.C. board, the receiver
P.C. board and the display P.C. board
(1) Remove the panel and the corner box. (Refer to 1.)
(2) Remove the screw of the electrical cover.
Remove the electrical cover.
(3) Remove the screws of the V.A. clamp.
Remove the V.A. clamp.
(4) Remove the screw of the terminal block.
(5) Remove the screws of the earth wire.
(6) Disconnect all the connectors and all the lead wires on the
electronic control P.C. board.
(7) Remove the R.L holder.
(8) Remove the electronic control P.C. board.
(9) Open the R.L holder, remove the receiver P.C. board and
the display P.C. board.
Screw of the
corner box
Photo 2
Screws of the earth wire
Fan motor
connectors
Vane motor
connector
Indoor
electronic
control
P.C. board
R.L
Screw of
Receiver
holder the terminal P.C.
block
board
3. Removing the electrical box
(1) Remove the panel and the corner box. (Refer to 1.)
(2) Remove the electrical cover. (Refer to 2.)
(3) Disconnect the connector of the indoor coil thermistor.
(4) Disconnect the motor connector (CN211 and CN121) and
the vane motor connector (CN151) on the electronic
control P.C. board.
(5) Remove the screws of earth wire.
(6) Remove the fan motor lead wire and indoor coil thermistor
from the electrical box.
(7) Remove the lead wire of vane motor from the bottom of
electrical box.
(8) Remove the screw of the electrical box and remove the
electrical box.
OBH529A
35
Photo 3
Screw of
the electrical
cover
Screw of the
V.A. clamp
Screws of the earth wire
Screw of the
electrical cover
Screw of the
electrical box
OPERATING PROCEDURE
4. Removing the vane motor
(1) Remove the panel and the corner box. (Refer to 1.)
(2) Remove the electrical cover. (Refer to 2.)
(3) Remove the lead wire of vane motor. (Refer to 3.)
(4) Remove the R.L. holder.
(5) Pull out the drain hose from the nozzle assembly and
remove the nozzle assembly.
(6) Remove the screws of the vane motor and disconnect the
connector.
(7) Remove the vane motor.
PHOTOS
Photo 4
Vane motors
Screws
of the
vane
motor
Photo 5 Screws of the
vane motor
Vane motor
5. Removing the line flow fan and the indoor fan motor
(1) Remove the panel and the corner box. (Refer to 1.)
(2) Remove the electrical box. (Refer to 3.)
(3) Pull out the drain hose from the nozzle assembly and
remove the nozzle assembly.
(4) Remove the water cut.
(5) Slide the hole cover and remove the hole cover.
(6) Remove the hexagon socket set screw from the line flow
fan.
(7) Remove the screws of the fan motor and remove the fan
motor. (Be careful not to drop the fan motor because it is
heavy.)
(8) Remove the screws of the left side of the heat exchanger.
(9) Lift the left side of the heat exchanger.
(10) Remove the line flow fan.
Photo 8
Photo 6
Screws of
the left side
of the heat
exchanger
Photo 7
Indoor coil
thermistor
Water cut
Hole
cover
Screws of the fan motor
HEAD OFFICE: TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN
Copyright 2008 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD
Distributed in Aug. 2011. No.OBH529 REVISED EDITION-A
Distributed in Dec. 2008. No.OBH529 5
Made in Japan
New publication, effective Aug. 2011
Specifications subject to change without notice.