Download Mitsubishi MSH-A18ND Service manual

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Page 1
Revision A:
● Remote controller model “KM04B” has
been added.
Please void OB404.
SPLIT-TYPE, AIR CONDITIONERS
INDOOR UNIT
SERVICE MANUAL
No. OB404
REVISED EDITION-A
Wireless type
Models
MS-A18NDMS-A24NDMS-A30ND-
S1
S1
S1
Outdoor unit service manual
MU-A·ND Series (OB405)
CONTENTS
MS-A18ND
MS-A24ND
MS-A30ND
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················2
3. SPECIFICATION·················································4
4. OUTLINES AND DIMENSIONS ·························5
5. WIRING DIAGRAM ············································6
6. REFRIGERANT SYSTEM DIAGRAM ················8
7. SERVICE FUNCTIONS ······································9
8. TROUBLESHOOTING······································11
9. DISASSEMBLY INSTRUCTIONS ····················19
10. PARTS LIST······················································21
11. RoHS PARTS LIST···········································24
NOTE:
• This service manual describes technical data of the indoor units.
• RoHS compliant products have <G> mark on the spec name plate.
For servicing of RoHS compliant products, refer to the RoHS Parts List.
TM
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Page 2
Revision A:
• Remote controller model “KM04B” has been added.
There are two remote controller models for “ S1 ”. (KP0B, KM04B)
You can use the remote controller model “KP0B” and “KM04B”.
The remote controller model “KM04B” is supplied as service parts for “
1
S1
”.
TECHNICAL CHANGES
w : change
Frequency
New Model
Old Model
Indoor unit:Unit size:W1,015mmoH320mmoD190mm ➞ W1,100mmoH325mmoD258mm
Electricity receiving unit: Indoor unit ➞ Outdoor unit
Rated voltage: 220V ➞ 220-230V
60Hz
MS-A18ND - S1
MS-18TN - S1 MS-18SN w
w
w
w
w
w
Frequency
60Hz
New Model
MS-A24ND - S1
Old Model
MS-24TN - S1 MS-24SN Indoor unit:Unit size:W1,015mmoH320mmoD190mm ➞ W1,100mmoH325mmoD258mm
w
w
Electricity receiving unit: Indoor unit ➞ Outdoor unit
w
w
Rated voltage: 220V ➞ 220-230V
w
w
C1
C2
MS-A30ND - S1
New model
2
PART NAMES AND FUNCTIONS
INDOOR UNIT
MS-A18ND
MS-A24ND
MS-A30ND
Air cleaning filter
: White bellows type
Grille
Air inlet
Front Panel
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
2
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ACCESSORIES
1
2
3
4
5
6
7
8
9
MS-A18ND
MS-A24ND
MS-A30ND
1
7
1
2
2
1
1
2
Installation plate
Installation plate fixing screw 4 x 25 mm
Remote controller holder
Fixing screw for 3 3.5 x 16 mm (Black)
Battery (AAA) for remote controller
Wireless remote controller
Felt tape (Used for left or left-rear piping)
Air cleaning filter
Pipe cover
REMOTE CONTROLLER
MS-A18ND
MS-A24ND
MS-A30ND
Signal transmitting section
Operation display section
OPERATE/ STOP
(ON/ OFF)button
PM
AM
TOO
ON/OFF WARM
TOO
COOL
TEMPERATURE buttons
Open the front lid.
Indication of remote controller
model is on back.
CLOCK
PM
AM
TOO
ON/OFF WARM
VANE button
(Horizontal vane button)
TOO
COOL
FAN
STOP
VANE
START
FAN
FAN SPEED CONTROL button
OFF-TIMER button
I FEEL COOL
DRY
MODE WIDE VANE
HR.
OPERATION SELECT button
ECONO COOL
LONG
ECONO COOL button
RESET CLOCK
WIDE VANE button
(Vertical vane button)
MIN.
ON-TIMER button
HR. button
MIN. button
(TIME SET button)
CLOCK SET button
LONG button
RESET button
3
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SPECIFICATION
MS-A18ND
Indoor model
MS-A24ND
Cooling
Single phase
220-230V, 60Hz
Function
Power supply
Special
remarks
Fan
motor
Electrical
data
Capacity Air flow (High/Med./Low)
Running current
Power input
Auxiliary heater
Power factor
Fan motor current
Model
Winding
resistance(at 20:)
Dimensions WOHOD
Weight
Air direction
Sound level (High/Med./Low)
Fan speed (High/Med./Low)
Fan speed regulator
Thermistor RT11(at 25:)
Thermistor RT12(at 25:)
Remote controller model
MS-A30ND
K /h
A
W
A(kW)
%
A
948/762/576
"
mm
kg
dB
rpm
45/40/34
1,220/1,020/810
k"
k"
NOTE:Test conditions are based on ISO 5151 / SSA 385
Cooling : Indoor
DB27°C WB19°C / DB29°C WB19°C
Outdoor DB35°C WB24°C / DB46°C WB24°C
Indoor-Outdoor piping length : 5 / 7.5 m
4
948/834/714
0.37
81
—
100-95
0.37
RC4V40-AA
WHT-BLK 138.2
RED-BLK 159.0
1,100O325O258
16
5
45/41/37
1,220/1,100/970
3
10
10
KP0B / KM04B
948/804/660
45/41/37
1,220/1,070/910
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OUTLINES AND DIMENSIONS
MS-A18ND MS-A24ND MS-A30ND
INDOOR UNIT
Unit: mm
Installation plate
Indoor unit
98
7.5
173
98
414.5
414.5
258
325
Air in
791
56
253
Air out
Insulation [28
19
162
58
Wireless remote controller
5
{
{
{
Liquid line [ 6.35- 0.5m
Gas line [ 12-0.43m
Insulation [ 50 O.D
5
[ 32 I.D
Installation plate
for MS-A18ND
Liquid line [ 9.52- 0.5m
Gas line [ 12-0.43m
Insulation [ 50 O.D
[ 32 I.D
for MS-A24ND
Liquid line [ 9.52- 0.5m
Gas line [ 16-0.43m
Insulation [ 50 O.D
[ 32 I.D
for MS-A30ND
Drain hose [16
(Connected part O.D)
Wall hole [75
1100
173
2.5
47
255.5
1068
315
4
Page 5
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WIRING DIAGRAM
MS-A18ND MS-A24ND
INDOOR UNIT
TO OUTDOOR
UNIT
CONNECTING
220-230V~
HIC1
CN201
2TBWHT
F12
BLU
BLU
N BLU
1
2
4
52C
CN
111
RT11
CN
121
NR11
220-230V~
C11
L
RT12
3
3
2
1
BLU
CN
112
BRN
F11
SR141
1
3
4
3
BLK
GRY
YLW
BRN
WHT
RED
MF
CN211
GRN/YLW
CN
151
CN
102
15
MV2 MV2 MV1
CN
101
ELECTRONIC CONTROL P.C. BOARD
3
3
DISPLAY
P.C. BOARD
RECEIVER
P.C. BOARD
REMOTE
CONTROLLER
SYMBOL
NAME
NAME
FUSE(3.15A)
MV2
VERTICAL VANE MOTOR
TB
TERMINAL BLOCK
THERMAL FUSE(93:)
NR11
VARISTOR
52C
COMPRESSOR CONTACTOR
DC/DC CONVERTER
RT11
ROOM TEMPERATURE THERMISTOR
INDOOR FAN MOTOR(INNER PROTECTOR)
RT12
INDOOR COIL THERMISTOR
F11
F12
MF
SYMBOL
HORIZONTAL VANE MOTOR
INDOOR FAN CAPACITOR
HIC1
NAME
SYMBOL
MV1
C11
NOTE: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.
/: Terminal block,
: Connector
6
SR141
SOLID STATE RELAY
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MS-A30ND
INDOOR UNIT
TO OUTDOOR
UNIT
CONNECTING
TB
12V
3
N
HIC1
3
2
1
BLU
CN
151
C11
CN
102
15
F11
CN
101
3
MV2 MV2 MV1
CN
121
NR11
TAB12
BRN
RT13
RT12
CN112
CN201
RED
GRN/YLW
220-230V~ 2
4
3
2
1
SR141
1
3
4
3
BLK
GRY
YLW
BRN
WHT
RED
CN211
CN
ELECTRONIC CONTROL P.C. BOARD 111
RT11
3
DISPLAY
P.C. BOARD
RECEIVER
P.C. BOARD
REMOTE
CONTROLLER
SYMBOL
NAME
NAME
SYMBOL
C11
INDOOR FAN CAPACITOR
MV2
VERTICAL VANE MOTOR
F11
FUSE(3.15A)
NR11
VARISTOR
DC/DC CONVERTER
RT11
ROOM TEMPERATURE THERMISTOR
INDOOR FAN MOTOR(INNER PROTECTOR)
RT12
MAIN INDOOR COIL THERMISTOR
HORIZONTAL VANE MOTOR
RT13
SUB INDOOR COIL THERMISTOR
HIC1
MF
MV1
NOTE: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.
/: Terminal block,
: Connector
7
SYMBOL
SR141
TB
MF
NAME
SOLID STATE RELAY
TERMINAL BLOCK
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REFRIGERANT SYSTEM DIAGRAM
MS-A18ND
Unit : mm
INDOOR UNIT
Refrigerant pipe
[12.7
(with heat insulator)
Indoor
heat
exchanger
Main indoor coil
thermistor
RT12
Flared connection
Distributor
RT11
Room
temperature
thermistor
Strainer
#50
Flared connection
Refrigerant pipe
[6.35
(with heat insulator)
MS-A24ND
MS-A30ND
INDOOR UNIT
INDOOR UNIT
Refrigerant pipe
[15.88
(with heat insulator)
Indoor
heat
exchanger
Main indoor coil
thermistor
RT12
Refrigerant pipe
[15.88
(with heat insulator)
Indoor
heat
exchanger
Flared connection
Main indoor coil
thermistor
RT12
Flared connection
Sub indoor coil
thermistor
RT13
Room temperature
thermistor
RT11
Room temperature
thermistor
RT11
Strainer
#50
Strainer
#50
Flared connection
Flared connection
Refrigerant pipe
[6.35
(with heat insulator)
Refrigerant pipe
[9.52
(with heat insulator)
Refrigerant flow in cooling
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SERVICE FUNCTIONS
MS-A18ND
MS-A24ND
MS-A30ND
7-1. TIMER SHORT MODE
For service, set time can be shortened by short circuit of JPG and JPS the electronic control P.C. board.
The time will be shortened as follows. (Refer to 8-6.)
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.
7-2. 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 : KP0B
J2
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.
J1
Remote controller model : KM04B
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.
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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 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.
7-3. 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.
How to release “AUTO RESTART FUNCTION”
1Turn off the main power for the unit.
2Pull out the indoor electronic control P.C. board and the display P.C. board.(Refer to 9.2.)
3Solder the Jumper wire or the RESISTOR 220" to the RESISTOR JR07 on the indoor electronic control P.C.board.
(Refer to 8-6.)
C11
SW1
RA102
CN151 CN121
CN111
CN112
CN201
IC101
IC152
JR07
Operation
1If the main power has been cut, the operation settings remain.
2After the power is restored, the unit automatically resumes the same operation as the memory has recorded.
However, it takes the compressor at least 3 minutes to get started.
NOTE:
•The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the remote
controller.
•If the 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.
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TROUBLESHOOTING
MS-A18ND
MS-A24ND
MS-A30ND
8-1. 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 unit first with the remote controller, and then 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.
Housing point
Lead wiring
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 discolouration.
4) When troubleshooting, refer to 8-2. and 8-3.
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.
2 Press the RESET button with tip end of ball point
1 Remove the front lid and insert batteries.
pen or the like, and 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 are correct.
RESET button
NOTE : 1. If the RESET button is not pressed, the remote controller may not operate correctly.
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8-2. Instruction of troubleshooting
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate.
Outdoor unit
operates in
only Test Run
operation. w
Check room
temperature
thermistor.
Refer to 8-6.
"Test point
diagram and
voltage".
MS-A30ND
Flash on and
off at 0.5-second
intervals
Cause:
Indoor/
Outdoor unit
• Mis-wiring
MU-A30ND
Outdoor unit
doesn't
operate
even in
Test Run
operation.w
Refer to
"Check of
outdoor unit".
2-time flash
Cause:
Indoor unit
• Trouble of
room temperature/
indoor coil
thermistor
Check room
temperature
Refer to
thermistor
8-5. D
and indoor
"How to
coil thermischeck
tor.
mis-wiring
Refer to 8-6.
(When
"Test point
outdoor unit
doesn't work)". diagram and
voltage".
w
Indoor unit
operates.
Outdoor unit
doesn't operate
normally.
MU-A24ND - S2
MU-A30ND
Outdoor unit
doesn't
stop even
if indoor unit
stop.
Refer to
"Check of
outdoor unit".
3-time flash
Cause:
Indoor unit
• Trouble of
indoor fan
motor
Refer to
8-5. A
"Check of
indoor fan
motor".
Indoor unit
doesn't receive
the signal from
remote controller.
MU-A30ND
Outdoor unit
repeats start
and stop.
Refer to
"Check of
solenoid
valve coil".
4-time flash
Cause:
Indoor unit
• Trouble of
indoor
control
system
Indoor unit
operates, when
EMERGENCY
OPERATION
switch is pressed.
Indoor unit
doesn't operate,
when
EMERGENCY
OPERATION
switch is pressed.
Refer to 8-5. B
"Check of
remote controller
and receiver
P.C. board".
1. Check indoor /
outdoor
connecting wire.
2. Check of outdoor
fuse.
(MU-A18/A24ND)
3. Refer to 8-5. C
"Check of indoor
electronic control
P.C. board".
MU-A30ND
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
Replace the
indoor
electronic
control
P.C. board.
OPERATION INDICATOR
lamp on the indoor unit is
flashing on and off.
Refer to
"Check of
outdoor
thermistor".
MU-A30ND
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Replace the
deicer
P.C. board.
MU-A30ND
10-time flash
Cause:
Outdoor unit
• Trouble of
low discharge
temperature
protection
Refer to
"Check of
LEV".
Refer to outdoor unit service manual.
"Test Run operation" means the operation within 30 minutes after EMERGENCY OPERATION switch is pressed.
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8-3. Troubleshooting check table
• The following indication applies regardless of shape of the indicator.
· Flashing of the OPERATION INDICATOR lamp (the left-hand side lamp) indicates
possible abnormalities.
· The OPERATION INDICATOR lamp (the left-hand side lamp) is lighting during
Not lighted normal operation.
Operation Indicator
Lighted
Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
Self check table
No.
Abnormal
point
Indication
Symptom
0.5-second ON
1
Outdoor unit
does not
operate.
Mis-Wiring
Detection method
Check point
3 minutes after power supply turns ON, when
serial signal is not received.
• Refer to 8-5. D "How to check
mis-wiring ".
Detect Indoor coil/room temperature
thermistor short or open circuit every 8
seconds during operation.
• Refer to the characteristics of
indoor coil thermistor,
sub indoor coil thermistor,
and room temperature
thermistor on 8-6.
0.5-second OFF
Indoor coil
thermistor
2-time flash
Outdoor unit
does not
operate.
2
Room
temperature
thermistor
2.5-second OFF
Indoor fan
motor repeats
12 seconds
ON and 3
minutes OFF.
When the
indoor fan
motor breaks,
the fan keeps
stopping.
3-time flash
3
Indoor fan
motor.
2.5-second OFF
4-time flash
4
Indoor
control
system
2.5-second OFF
Outdoor unit
does not
operate.
6-time flash
5
Outdoor
thermistors
MU-A30ND
Outdoor unit
does not
operate.
2.5-second OFF
6
Outdoor
control
system
MU-A30ND
7-time flash
Outdoor unit
does not
operate.
When rotational frequency feedback signal is
not emitting during 12-second indoor fan
operation.
When nonvolatile memory data cannot be
read properly on indoor electronic control P.C.
board.
• Refer to 8-5. A "Check of
indoor fan motor".
• Replace the indoor electronic
control P.C. board.
<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
• Replace the deicer P.C.
board.
Refer to "Check of outdoor
thermistor".
Refer to outdoor unit service
manual.
When nonvolatile memory data cannot be
read properly on deicer P.C. board.
• Replace the deicer P.C.
board.
Refer to outdoor unit service
manual.
2.5-second OFF
When discharge temperature has been 50:
or less for 20 minutes.
10-time flash
Low
discharge
7 temperature
protection
MU-A30ND
Outdoor unit
does not
operate.
• Refer to "Check of LEV".
• Check refrigerant circuit and
refrigerant amount.
Refer to outdoor unit service
manual.
2.5-second OFF
NOTE : When the indoor unit has started operation and the above 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.
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8-4. Trouble criterion of main parts
MS-A18ND
MS-A24ND
MS-A30ND
INNER
PROTECTOR
135i 5: OPEN
86i15: CLOSE
Horizontal vane
motor(MV1)
Vertical vane
motor(MV2)
Motor part
Measure the resistance with a tester.
(Part temperature 10°C ~ 30°C)
Refer to 8-6. “Test point diagram and voltage”, “Indoor electronic control P.C.
board”, the chart of thermistor.
Measure the resistance between the terminals with a tester.
(Coil wiring temperature10°C ~ 30°C)
Color of lead wire
Normal
WHT - BLK
BLK - RED
132 ~ 144 "
152 ~ 166 "
MAIN
AUX.
Measure the voltage Power ON.
Sensor part
Indoor fan
motor (MF)
Figure
Check method and criterion
Part name
Room
temperature
thermistor (RT11)
Indoor coil
thermistor
(RT12(main), RT13(sub))
Color of lead wire
Normal
BRN - YLW
4.5 ~ 5.5 V
YLW - GRY
(When fan revolved one time)
0V➔5V➔0V
(Approx.)
Measure the resistance between the RED terminals and other ones.
(Winding temperature10°C ~ 30°C)
BLK
PNK
REDWHT
ROTOR
ORN
RED
Normal
282 ~ 306 "
YLW
BLU
P:INNER PROTECTOR
14
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06.4.26 6:01 PM
Page 15
8-5. Troubleshooting flow
When OPERATION INDICATOR lamp flashes 3-time.
Indoor fan motor doesn’t operate.
A Check of indoor fan motor
Turn OFF the power supply.
Check connector CN211 visually.
No
Yes
Are lead wires connected?
Is soldered point of the connector
correctly soldered?
No
Yes
Resolder it.
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.4 and then No.3 and No.4.
Is resistance 0 (short circuit) or ∞ (open circuit)?
Yes ( 0 or ∞ )
Repair the indoor fan motor.
No
(others)
No
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 No.2(+)
and No.3(-) on CN121.
Does voltage repeat 0V DC and 5V DC?
Yes
Replace the indoor electronic control P.C. board.
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but doesn’t operate with the remote controller.
B Check of remote controller and receiver P.C. board
w Check if the remote controller is exclusive for this air conditioner.
Switch on the remote controller.
Is LCD display on the remote controller visible?
No
(not clear)
Replace the batteries.
(Refer to 8-1.4.)
Yes
Remove batteries, then set them back and
press the RESET button.
Check if the unit operates with remote controller.
Does the unit operate with remote
controller?
No
Turn on a radio to AM and press switch 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 1m?
Yes
● Reinstall the unit away from lights.
● Attach a filter on receiving part.
No
Measure the voltage between receiver P.C. board connector CN301 No.1(+) and No.3(-) when
the remote controller button is pressed.
Is the voltage approx. 4V DC?
No(5V or 0V DC)
Replace the receiver P.C. board.
15
Yes
Replace the indoor electronic control
P.C. board
OB404A--1.qxp
06.4.26 6:01 PM
Page 16
The unit doesn’t operate with the remote controller.
Also, the OPERATION INDICATOR lamp doesn’t light up by pressing the EMERGENCY OPERATION switch.
C Check of indoor electronic control P.C. board
Check both “parts side” and “pattern
side” of the indoor electronic control P.C.
board visually.
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.
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.
Varistor (NR11)
Indoor electronic
control P.C. board
Turn OFF the
power supply.
Replace the vane
motor.
Yes
Is the winding
resistance of
vane motor 0 "?
Fuse (F11)
Replace the fuse.
No
Is the winding
resistance of
fan motor 0 "?
Yes
Replace the fan
motor.
Is fuse(F11) blown?
MS-A30ND
No
Is varistor(NR11) burnt?
Yes
Replace the varistor.
16
F12
1
2
Indoor electronic
control P.C. board
No
Yes
3
2
1
CN201
Terminal
block
2
N
L
No
MS-A18/A24ND
Measure the
resistance
between
CN201 1 on
the indoor
electronic control
P.C. board and N
on the terminal
block with a tester.
Replace the indoor
electronic control
P.C. board.
Yes
Is resistance approx. 0"?
No (∞)
Replace the fuse (F12).
OB404A--1.qxp
06.4.26 6:01 PM
Page 17
When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second.
Outdoor unit doesn’t operate.
D How to check mis-wiring
MS-A30ND
w 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.
• Press EMERGENCY OPERATION switch once.
When the unit has mis-wiring, in 3 minutes,
OPERATION INDICATOR lamp on indoor unit
flash on and off at 0.5 second intervals. w
Yes
Make them sure.
Is this mis-wiring, poor contact,
or wire disconnection?
No
1. Turn OFF the power supply and disconnect only terminal block 3
of indoor/ outdoor connecting wire on indoor side.
2. Short-circuit terminal block N-3 by lead wire.
3. Turn ON the power supply and press EMERGENCY OPERATION switch once.
Is there 1V DC detected between both ends
of PS132 on the indoor electronic control P.C.
board ?
However, the stylus of a tester would be
between 0 and 20V.
Yes
No
Replace the indoor electronic
control P.C. board.
• Turn OFF the power supply.
• Disconnect the lead wire that terminal
block N-3 is short-circuited.
• Connect ON indoor/ outdoor connecting wire.
Turn ON the power supply.
Is there 220-230V AC between L-N
on the outdoor terminal block?
No
Check the outdoor power supply
and connection of wiring.
Yes
Is there 5V DC between J101 + -J401 - ?
No
Replace the deicer P.C. board.
Yes
When EMERGENCY OPERATION
is operated, is there 10V DC between both
ends of R601 on the deicer P.C. board?
However the stylus of a tester would be
between 5 ~10V.
No
Yes
Replace the deicer P.C. board.
Refer to outdoor unit service manual.
17
Make the wiring between CN730
on the deicer P.C. board and
outdoor terminal block correct.
OB404A--1.qxp
06.4.26 6:01 PM
Page 18
8-6. Test point diagram and voltage
MS-A18ND MS-A24ND MS-A30ND
Indoor electronic control P.C.board
Varistor (NR11)
Fan motor power supply
220-230V AC(CN211)
}
Power supply input
220-230V AC
+
Fuse (F11)
250V AC 3.15A
} 5V DC
Room temperature
thermistor(RT11)
Main indoor coil
thermistor(RT12)
PS132
MS-A30ND
CN121
MS-A30ND
Sub indoor coil
thermistor(RT13)
Vane motor
power supply
(CN151)
Emergency operation
switch
Timer short mode point
(JPS, JPG)
(Refer to 7-1.)
+
}
12V DC
CN301
Release of Auto restart function
Solder the Jumper wire or the
Resistor 220" to the Resistor
JR07. (Refer to 7-3.)
Resistance (k")
Main indoor coil thermistor (RT12)
Sub indoor coil thermistor (RT13)
Room temperature thermistor (RT11)
Temperature (:)
18
OB404A--1.qxp
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06.4.26 6:01 PM
Page 19
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.
(2) The terminal with this connector has the
locking mechanism.
Sleeve
Locking lever
1Slide the sleeve.
2Pull the terminal while
pushing the locking
lever.
1Hold the sleeve, and
pull out the terminal
slowly.
Connector
MS-A18ND MS-A24ND MS-A30ND
INDOOR UNIT
OPERATING PROCEDURE
PHOTOS
1. Removing the front panel
(1) Remove the screws 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
Front panel
Screws
2. Removing the electronic control P.C. board, the receiver
P.C. board and the display P.C. board
(1) Remove the front panel. (Refer to 1.)
(2) Remove the screw of the electrical cover.
Remove the electrical cover.
(3) Remove the screw of the V.A. clamp.
Remove the V.A. clamp.
(4) Remove the screw of the terminal block.
(5) Remove the screw of the ground 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.
Photo 2
Screws of the ground wire
Fan motor
connectors
Vane motor
connector
Indoor
electronic
control
P.C.board
Screw of
the electrical
cover
Screw of
the terminal
block
19
R.L
holder
Receiver Screw of the
V.A. clamp
P.C.
board
OB404A--1.qxp
06.4.26 6:01 PM
Page 20
OPERATING PROCEDURE
PHOTOS
3. Removing the electrical box
(1) Remove the front panel. (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 screw of ground 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 fixing the electrical box, remove the
electrical box.
Photo 3
4. Removing the vane motor
(1) Remove the front panel. (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, remove
the nozzle assembly.
(6) Remove the screws of the vane motor, disconnect the connector.
(7) Remove the vane motor.
Photo 4
Screws of the ground wire
Screw of the
electrical cover
Screw of the
electrical box
Vane motors
Photo 5 Screws of the
vane motor
Vane motor
5. Removing the line flow fan and the indoor fan motor
(1) Remove the front panel. (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 water cut.
(5) Slide the hole cover, remove the hole cover.
(6) Remove the hexagon socket set screw from the line flow
fan.
(7) Remove the fan motor after removing screws, which fasten
the motor, but be careful not to drop it because of its heavy
weight.
(8) Remove the screws fixing the left side of the heat
exchanger.
(9) Lifting the left side of the heat exchanger.
(10) Remove the line flow fan.
Photo 6
Screws fixing
the left side
of the heat
exchanger
Photo 7
Indoor
coil
thermistor
Photo 8
Water cut
Hole
cover
Screws fixing the fan motor
20
Screws
of the
vane
motor
OB404A--1.qxp
06.4.26 6:01 PM
10
Page 21
PARTS LIST (non-RoHS compliant)
MS-A18ND
MS-A24ND
MS-A30ND
10-1. INDOOR UNIT STRUCTURAL PARTS
10-2. INDOOR UNIT HEAT EXCHANGER
1
2
11
3
4
CATCH
9
(See 10-5.)
7
5
SCREW
CAP
12
13
6
8
10-1. INDOOR UNIT STRUCTURAL PARTS
Part number that is circled is not shown in the illustration.
No.
1
2
3
4
5
6
7
8
9
10
Part No.
E02
E02
E02
E02
E02
E02
E02
E02
527
685
888
408
685
888
685
534
970
234
000
142
067
010
975
100
E02 888 007
Part name
Q'ty/unit
Symbol
in Wiring MS-A18 MS-A24 MS-A30
Diagram ND- S1
ND- S1
ND- S1
1
1
1
4
3
1
1
2
2
1
INSTALLATION PLATE
BOX
FRONT PANEL ASSEMBLY
CATCH
SCREW CAP
GRILLE
CORNER BOX RIGHT
CATECHIN AIR FILTER
AIR CLEANING FILTER
LAMP PANEL
1
1
1
4
3
1
1
2
2
1
1
1
1
4
3
1
1
2
2
1
Remarks
Including No.4,5,6
4PCS/SET
3PCS/SET
1PCE/SET
MAC-1700FT
10-2. INDOOR UNIT HEAT EXCHANGER
11
12
13
E02
E02
E02
E02
E02
E02
E02
E02
817
947
890
179
138
A16
151
527
620
620
620
667
666
666
667
667
INDOOR HEAT EXCHANGER
INDOOR HEAT EXCHANGER
INDOOR HEAT EXCHANGER
UNION(GAS)
UNION(GAS)
UNION(GAS)
UNION(LIQUID)
UNION(LIQUID)
1
1
1
1
1
1
1
1
1
21
{12.7
{15.88
{15.88
{6.35
{9.52
Price
OB404A--1.qxp
06.4.26 6:01 PM
Page 22
PARTS LIST (non-RoHS compliant)
MS-A18ND
MS-A24ND
MS-A30ND
10-3. INDOOR UNIT FUNCTIONAL PARTS AND
ELECTRICAL PARTS
20
1
10-4. ACCESSORY AND
REMOTE CONTROLLER
19
24
2
25
3
SLEEVE
BEARING
4
12
17
11
ROOM
TEMPERATURE
THERMISTOR
5
6
13
18
10
7
FUSE
8
9
VARISTOR
14 15
16
10-3. INDOOR UNIT FUNCTIONAL PARTS AND ELECTRICAL PARTS
Part numbers that are circled are not shown in the illustration.
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
Part No.
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
E02
527
408
001
408
996
685
685
A49
817
527
527
448
408
528
527
949
950
951
527
527
888
814
408
947
527
528
529
408
302
509
504
702
235
040
041
382
385
034
300
303
303
329
468
452
452
452
308
333
375
375
311
311
311
034
034
381
Part name
Q'ty/unit
Symbol
in Wiring MS-A18 MS-A24 MS-A30
ND- S1
ND- S1
Diagram ND- S1
LINE FLOW FAN
BEARING MOUNT
SLEEVE BEARING
DRAIN HOSE
NOZZLE
VANE UPPER
VANE LOWER
F11
FUSE
NR11
VARISTOR
VANE CRANK SET
MF
INDOOR FAN MOTOR ASSEMBLY
MV2
VERTICAL VANE MOTOR
MV1
HORIZONTAL VANE MOTOR
DISPLAY P.C. BOARD
RECEIVER P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
ROOM TEMPERATURE THERMISTOR RT11
MOTOR BAND
TB
TERMINAL BLOCK
TB
TERMINAL BLOCK
RT12
INDOOR COIL THERMISTOR
RT12
INDOOR COIL THERMISTOR
RT12, RT13
INDOOR COIL THERMISTOR
VANE MOTOR SUPPORT SET (RIGHT)
VANE MOTOR SUPPORT SET (LEFT)
F12
THERMAL FUSE
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
Remarks
3.15A
RC4V40Including RUBBER MOUNT
RIGHT&LEFT
UP&DOWN
AUTO RESTART
Including No.15
AUTO RESTART
Including No.15
AUTO RESTART
Including No.15
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
10-4. ACCESSORY AND REMOTE CONTROLLER
24
25
E02 527 426
E02 527 083
REMOTE CONTROLLER
REMOTE CONTROLLER HOLDER
22
1
1
KM04B
Price
OB404A--1.qxp
06.4.26 6:01 PM
Page 23
PARTS LIST (non-RoHS compliant)
10-5. AIR CLEANING FILTER
● AIR CLEANING FILTER removes fine dust of 0.01 micron from air by means of static electricity.
● Normal life of AIR CLEANING FILTER is 4 months. However, when it becomes dirty, replace it as soon as possible.
● Clogged AIR CLEANING FILTER may reduce the air conditioner capacity or cause frost on the air outlet.
● DO NOT reuse AIR CLEANING FILTER even if it is washed.
● DO NOT remove or attach AIR CLEANING FILTER during unit operation.
Part No.
Model
MS-A18ND MS-A24ND MS-A30ND -
S1
S1
MAC-1700FT
S1
Air cleaning filter (White bellows type)
23
OB404A--1.qxp
11
06.4.26 6:01 PM
Page 24
RoHS PARTS LIST (RoHS compliant)
MS-A18ND
MS-A24ND
MS-A30ND
11-1. INDOOR UNIT STRUCTURAL PARTS
11-2. INDOOR UNIT HEAT EXCHANGER
1
2
11
3
4
CATCH
9
(See 11-5.)
7
5
SCREW
CAP
12
13
6
8
11-1. INDOOR UNIT STRUCTURAL PARTS
No.
RoHS
Part number that is circled is not shown in the illustration.
1
2
3
4
5
6
7
8
9
10
G
G
G
G
G
G
G
G
G
G
Part No.
E12
E12
E12
E12
E12
E12
E12
E12
527
685
888
408
685
888
685
534
970
234
000
142
067
010
975
100
E12 888 007
Part name
Q'ty/unit
Symbol
in Wiring MS-A18 MS-A24 MS-A30
Diagram ND- S1
ND- S1
ND- S1
1
1
1
4
3
1
1
2
2
1
INSTALLATION PLATE
BOX
FRONT PANEL ASSEMBLY
CATCH
SCREW CAP
GRILLE
CORNER BOX RIGHT
CATECHIN AIR FILTER
AIR CLEANING FILTER
LAMP PANEL
1
1
1
4
3
1
1
2
2
1
1
1
1
4
3
1
1
2
2
1
Remarks
Including No.4,5,6
4PCS/SET
3PCS/SET
1PCE/SET
MAC-1700FT
11-2. INDOOR UNIT HEAT EXCHANGER
G E12 817 620
11 G E12 947 620
G E12 890 620
G E12 179 667
12 G E12 138 666
G E12 A16 666
G E12 151 667
13
G E12 527 667
INDOOR HEAT EXCHANGER
INDOOR HEAT EXCHANGER
INDOOR HEAT EXCHANGER
UNION(GAS)
UNION(GAS)
UNION(GAS)
UNION(LIQUID)
UNION(LIQUID)
1
1
1
1
1
1
1
1
1
24
{12.7
{15.88
{15.88
{6.35
{9.52
Price
OB404A--1.qxp
06.4.26 6:01 PM
Page 25
RoHS PARTS LIST (RoHS compliant)
MS-A18ND
MS-A24ND
MS-A30ND
11-3. INDOOR UNIT FUNCTIONAL PARTS AND
ELECTRICAL PARTS
20
1
11-4. ACCESSORY AND
REMOTE CONTROLLER
19
24
2
25
3
SLEEVE
BEARING
4
12
17
11
ROOM
TEMPERATURE
THERMISTOR
5
6
13
18
10
7
FUSE
8
9
VARISTOR
14 15
16
11-3. INDOOR UNIT FUNCTIONAL PARTS AND ELECTRICAL PARTS
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
RoHS
Part numbers that are circled are not shown in the illustration.
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
Part No.
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
527
408
001
408
996
685
685
A49
817
527
527
448
408
528
527
949
950
951
527
527
888
814
408
947
527
528
529
408
302
509
504
702
235
040
041
382
385
034
300
303
303
329
468
452
452
452
308
333
375
375
311
311
311
034
034
381
Part name
Q'ty/unit
Symbol
in Wiring MS-A18 MS-A24 MS-A30
ND- S1
ND- S1
Diagram ND- S1
LINE FLOW FAN
BEARING MOUNT
SLEEVE BEARING
DRAIN HOSE
NOZZLE
VANE UPPER
VANE LOWER
F11
FUSE
NR11
VARISTOR
VANE CRANK SET
MF
INDOOR FAN MOTOR ASSEMBLY
MV2
VERTICAL VANE MOTOR
MV1
HORIZONTAL VANE MOTOR
DISPLAY P.C. BOARD
RECEIVER P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
ELECTRONIC CONTROL P.C. BOARD
RT11
ROOM TEMPERATURE THERMISTOR
MOTOR BAND
TB
TERMINAL BLOCK
TB
TERMINAL BLOCK
RT12
INDOOR COIL THERMISTOR
RT12
INDOOR COIL THERMISTOR
INDOOR COIL THERMISTOR RT12, RT13
VANE MOTOR SUPPORT SET (RIGHT)
VANE MOTOR SUPPORT SET (LEFT)
F12
THERMAL FUSE
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
Remarks
3.15A
RC4V40Including RUBBER MOUNT
RIGHT&LEFT
UP&DOWN
AUTO RESTART
Including No.15
AUTO RESTART
Including No.15
AUTO RESTART
Including No.15
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
11-4. ACCESSORY AND REMOTE CONTROLLER
24 G
25 G
E12 527 426
E12 527 083
REMOTE CONTROLLER
REMOTE CONTROLLER HOLDER
25
1
1
KM04B
Price
OB404A--1.qxp
06.4.26 6:01 PM
Page 26
RoHS PARTS LIST (RoHS compliant)
11-5. AIR CLEANING FILTER
● AIR CLEANING FILTER removes fine dust of 0.01 micron from air by means of static electricity.
● Normal life of AIR CLEANING FILTER is 4 months. However, when it becomes dirty, replace it as soon as possible.
● Clogged AIR CLEANING FILTER may reduce the air conditioner capacity or cause frost on the air outlet.
● DO NOT reuse AIR CLEANING FILTER even if it is washed.
● DO NOT remove or attach AIR CLEANING FILTER during unit operation.
Part No.
Model
MS-A18ND MS-A24ND MS-A30ND -
S1
S1
MAC-1700FT
S1
Air cleaning filter (White bellows type)
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TM
HEAD OFFICE: TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN
C Copyright 2005 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD
Distributed in May 2006. No.OB404 REVISED EDITION-A 106
Reprinted in Apr. 2005. No.OB404 100
Distributed in Mar. 2005. No.OB404 6
Made in Japan
New publication, effective May 2006
Specifications subject to change without notice.