Mitsubishi Electric MU-A08ND-c1 User manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················3
3. SPECIFICATION·················································4
4. OUTLINES AND DIMENSIONS ·························5
5. WIRING DIAGRAM ············································8
6. REFRIGERANT SYSTEM DIAGRAM················9
7. PERFORMANCE CURVES······························12
8. TROUBLESHOOTING······································15
9. DISASSEMBLY INSTRUCTIONS ····················17
10. PARTS LIST······················································25
11. RoHS PARTS LIST···········································29
12. OPTIONAL PARTS···········································33
Wireless type
Models
SPLIT-TYPE, AIR CONDITIONERS
MU-A08ND-
MU-A08ND-
MU-A10ND-
MU-A10ND-
MU-A12ND-
MU-A15ND-
MU-A15ND- C2
C1
C1
C2
C1
C2
C1
MU-A10ND
MU-A12ND
TM
Revision:B
• MU-A10ND - has been added.
• RoHS PARTS LIST has been added.
C2
Please void OB403 REVISED EDITION-A.
NOTE:
This service manual describes technical data of outdoor units.
RoHS compliant products have <G> mark on the spec name plate.
For servicing of RoHS compliant products, refer to the RoHS Parts List.
OUTDOOR UNIT
Indoor unit service manual
MS-A•ND Series (OB402)
No. OB403
REVISED EDITION-B
OB403B--1.qxp 07.6.26 10:28 AM Page 1

2
TECHNICAL CHANGES1
MU-09SN - ➔MU-A08ND -
1. Compressor has been changed. (RH-130NGDT ➔2R10S3R236A-6B)
2. Outdoor fan motor has been changed. (RA6N23-AA ➔RA6N33-AA)
3. Compressor capacitor has been changed.
4. Outdoor fan motor capacitor has been changed.
MU-10SN - ➔MU-A10ND -
1. Outdoor unit model has been changed.
•Valve cover has been added.
•Dimension has been changed. (780Wo540Ho255D ➔800Wo550Ho285D)
2. Compressor has been changed. (RH145NGCT ➔RH145NHNT)
3. Outdoor fan motor has been changed. (RA6N33-AA ➔RA6N21-AB)
4. Compressor capacitor has been changed.
5. Outdoor fan motor capacitor has been changed.
6. Outdoor heat exchanger has been changed. ([9.52 L-Bend ➔[7 Flat)
MU-12SN - ➔MU-A12ND -
1. Outdoor unit model has been changed.
•Valve cover has been added.
•Dimension has been changed. (780Wo540Ho255D ➔800Wo550Ho285D)
2. Compressor has been changed. (RH167NHDT ➔RH174NHNT)
3. Outdoor fan motor has been changed. (RA6N33-AA ➔RA6N30-BA)
4. Compressor capacitor has been changed.
5. Outdoor fan motor capacitor has been changed.
6. Outdoor heat exchanger has been changed. ([9.52 L-Bend ➔[7 Flat)
MU-15SN - ➔MU-A15ND -
1. Compressor has been changed. (RH-207NHDT ➔RH207NRAT)
2. Outdoor fan motor has been changed. (RN6N50-BA ➔RA6V60-MA)
3. Compressor capacitor has been changed.
4. Outdoor fan motor capacitor has been changed.
MU-A08ND - ➔MU-A08ND -
MU-A15ND - ➔MU-A15ND -
1. Valve cover has been added.
MU-A10ND - ➔MU-A10ND -
1. Outdoor heat exchanger has been changed.
2. Capillary tube has been changed.
C2C1
C2C1
C2C1
C1C2
C1C2
C1C2
C1C2
Revision A:
• MU-A08ND - and MU-A15ND - have been added.
C2C2
Revision B:
• MU-A10ND - has been added.
• RoHS PARTS LIST has been added.
C2
OB403B--1.qxp 07.6.26 10:28 AM Page 2

3
PART NAMES AND FUNCTIONS
2
OUTDOOR UNIT
MU-A08ND
MU-A15ND
Air inlet
Piping
Drain hose
Air outlet
Drain outlet
(back and side)
MU-A10ND
MU-A12ND
Air inlet
Piping
Drain hose
Air outlet
Drain outlet
back and side : MU-A10ND
back : MU-A12ND
()
Air inlet
Piping
Drain hose
Air outlet
Drain outlet
(back and side)
OB403B--1.qxp 07.6.26 10:28 AM Page 3

SPECIFICATION
4
3
Outdoor model
Function
Power supply
Coefficient of performance (C.O.P)
Capacity
Dehumidification
Air flow
Starting current
Compressor motor current
Fan motor current
Model
Output
Winding
resistance (at 20:)
Model
Winding
resistance (at 20:)
Dimensions WOHOD
Weight
Sound level
Fan speed
Fan speed regulator
Refrigerant filling
capacity (R22)
Refrigeration oil (Model)
kW
R/h
K/h
A
A
A
W
"
"
mm
kg
dB
rpm
kg
cc
MU-A15ND
4.0
1.8
2280
35
5.62
0.5
2.97
RH207NRAT
1000
C-R 1.50
C-S 2.33
RA6V60-MA
WHT-BLK 116
BLK-RED 111
850o605o290
42
52
865
1.6
520 (MS56)
Electrical data
Fan motor
Special remarks Compressor
Capacity
MU-A08ND
2.2
0.5
1656
19
2.39
0.36
3.44
2R10S3R236A-6B
470
C-R 4.09
C-S 5.58
RA6N33-AA
WHT-BLK 150
BLK-RED 265
780o540o255
28
45
700
0.8
260 (ATM0S M60)
MU-A10ND
2.9
1.2
1896
26
3.86
0.26
3.12
RH145NHNT
700
C-R 2.74
C-S 3.78
RA6N21-AB
WHT-BLK 384
BLK-RED 259
32
46
820
0.6
1.1
300 (MS56)
1
MU-A12ND
3.6
1.7
1884
30
4.95
0.35
3.08
RH174NHNT
800
C-R 2.19
C-S 3.3
RA6N30-BA
WHT-BLK 312
BLK-RED 255
34
47
850
1.2
520 (MS56)
Cooling
Single phase
220-230V, 60Hz
800o550o285
C1
C2
NOTE: Test conditions are based on CNS14464, ISO5151.
Cooling : Indoor DB27°C / WB19°C
Outdoor DB35°C / WB24°C
Indoor-Outdoor piping length: 5 m
OB403B--1.qxp 07.6.26 10:28 AM Page 4

320
25
43-
35-
104
320 285 255
Service panel
Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [9.52
Liquid refrigerant
pipe joint
Refrigerant pipe
(flared) [6.35
Airout
Air in
Air in
Service port
155
90
74
260
10
780
500
122
40
540 109 32
110
147
Drainage
3 holes [33
5
OUTLINES AND DIMENSIONS4
Unit : mm
100mm or more
100mm or more
100mm or more
350mm or more
REQUIRED SPACE
400mm or more
OUTDOOR UNIT
MU-A08ND - C1
Unit : mm
OUTDOOR UNIT
MU-A08ND - C2
320
25
43-
35-
104
320 285 255
Service panel
Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [9.52
Liquid refrigerant
pipe joint
Refrigerant pipe
(flared) [6.35
Airout
Air in
Air in
Service port
155
90
81
74
260
10
780
500
122
40
540 109 32
110
147
Drainage
3 holes [33
100mm or more
100mm or more
100mm or more
350mm or more
REQUIRED SPACE
400mm or more
OB403B--1.qxp 07.6.26 10:28 AM Page 5

6
100mm or more
REQUIRED SPACE
350mm or more
500mm or more
100mm or more
100mm or more
30 Service panel
Service port
605
292
20
50 183
500
850 74
157
100
161
Gas refrigerant
pipe joint
Refrigerant pipe (flared)
[12.7
Liquid refrigerant
pipe joint
Refrigerant pipe (flared)
[6.35
30
o
35
o
Drainage
3 holes [33 Air out
Air in
Air in
248
35
350
50
290
310 345
20
355
90
Drainage
hole [16.2
MU-A15ND - C1 Unit : mm
Unit : mm
OUTDOOR UNIT
MU-A10ND
MU-A12ND
43-
35-
10
69
800
302.5 500
150
22.3
Handle
550
280
164.5
99.5
170.5
23 Service panel
Service port
285
344.5
44
400
Air in
Air out
Air in
(MU-A
10ND)
17.5
Bolt pitch for
installation
304~325
40
Liquid refrigerant pipe joint
Refrigerant pipe (flared) [6.35
Gas refrigerant pipe joint
Refrigerant pipe (flared) [9.52
(MU-A10ND)
Refrigerant pipe (flared) [12.7
(MU-A12ND)
2 holes 10X21
Basically open 100mm
or more without any
obstruction in front and
on both sides of the unit.
350mm or more
200mm or more
100mm or more
100mm or more
Open two sides of left,
right, or rear side.
Drain hole [42
REQUIRED SPACE
OUTDOOR UNIT
OB403B--1.qxp 07.6.26 10:28 AM Page 6

7
Unit : mm
OUTDOOR UNIT
MU-A15ND - C2
30 Service panel
Service port
605
292
20
50 183
500
850 81
74
157
100
161
Gas refrigerant
pipe joint
Refrigerant pipe (flared)
[12.7
Liquid refrigerant
pipe joint
Refrigerant pipe (flared)
[6.35
30
o
35
o
Drainage
3 holes [33 Air out
Air in
Air in
248
35
350
50
290
310 345
20
355
90
Drainage
hole [16.2
100mm or more
REQUIRED SPACE
350mm or more
500mm or more
100mm or more
100mm or more
OB403B--1.qxp 07.6.26 10:28 AM Page 7

WIRING DIAGRAM
8
5
MU-A08ND
SYMBOL
C1
C2
F1
SYMBOL
F2
MC
MF
SYMBOL
TB1,TB2
51C
NAME NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
FUSE (3.15A)
FUSE (20A)
COMPRESSOR (OUTER PROTECTOR)
OUTDOOR FAN MOTOR (INNER PROTECTOR)
TERMINAL BLOCK
OVERCURRENT RELAY
NOTE:1. About the indoor side electric wiring refer to the indoor unit electric wiring diagram for servicing.
2.Use copper conductors only. (For field wiring)
3. Symbols below indicate.
/: Terminal block
TB1
TB2
GRN/YLW
N
L
2
N
L
MF
C2
C1
S
RED MC R
C
BLK
POWER SUPPLY
220-230V ~/N 60Hz
CONNECTING
TO INDOOR UNIT
BRN
BLU
BLU
BLU
14 51C WHT WHT
BLK
WHT
RED
WHT
F1
F2
220-230V~
220-230V~
MU-A10ND
MU-A12ND
SYMBOL
C1
C2
SYMBOL
F
MC
SYMBOL
MF
TB1,TB2
NAME NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR FUSE (3.15A)
COMPRESSOR (INNER PROTECTOR)
OUTDOOR FAN MOTOR (INNER FUSE )
TERMINAL BLOCK
NOTE:1. About the indoor side electric wiring refer to the indoor unit electric wiring diagram for servicing.
2.Use copper conductors only. (For field wiring)
3. Symbols below indicate.
/: Terminal block :Connector
N
L
TB1
L
N
2
TB2 C2
220-230V~
C1
BLU BLU
WHT
WHT
RED
R
MC
C
WHT
CONNECTING
BLK
S
BLU
1
3
2MF
WHT
BLK
RED
GRN/YLW
RED
POWER SUPPLY
220-230V
~/N 60Hz
220-230V~
F
BRN
BLU
TO INDOOR
UNIT
OB403B--1.qxp 07.6.26 10:28 AM Page 8

9
REFRIGERANT SYSTEM DIAGRAM
6
Strainer
#100
MU-A08ND
Refrigerant pipe
(Option) [9.52
(with heat insulator)
Outdoor
heat
exchanger
Capillary tube
[3.0x[1.4x800
Refrigerant pipe
(Option) [6.35
(with heat insulator) Refrigerant flow in cooling
Unit: mm
Stop valve
(with service port)
Compressor
Flared connection
Flared connection
Stop valve
MU-A15ND
SYMBOL
C1
C2
SYMBOL
F
MC
SYMBOL
MF
TB1,TB2
NAME NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR FUSE (3.15A)
COMPRESSOR (INNER PROTECTOR)
OUTDOOR FAN MOTOR (INNER PROTECTOR)
TERMINAL BLOCK
NOTE:1. About the indoor side electric wiring refer to the indoor unit electric wiring diagram for servicing.
2.Use copper conductors only. (For field wiring)
3. Symbols below indicate.
/: Terminal block :Connector
CONNECTING
TO INDOOR UNIT
R
S
2
N
L
TB2
RED
ORN
BLU
WHT
GRN/YLW
C2 RED
MF
BLK
4
WHT
ORN
321
WHT
BLK
L
N
TB1
BRN
BLU C1 RED
C
MC
BLU
POWER SUPPLY
220-230V ~/N 60Hz
F
BLU
220-230V~
220-230V~
OB403B--1.qxp 07.6.26 10:28 AM Page 9

10
Capillary tube
{3.0 x {1.6x750
Stop valve
(with service port)
Stop valve
Compressor Strainer
#100
Outdoor heat
exchanger
Refrigerant flow in cooling
Refrigerant pipe
(Option){6.35
(with heat insulator)
Refrigerant pipe
(Option){12.7
(with heat insulator)
Flared
connection
Flared
connection
MU-A12ND Unit: mm
MU-A10ND
Refrigerant flow in cooling
Capillary tube
{3.0 x {1.6 x 500 (MU-A10ND - )
{3.0 x {1.6 x 850 (MU-A10ND - )
Compressor
Stop valve
(with service port)
Stop valve
Strainer
#100
Outdoor
heat
exchanger
C1
C2
Refrigerant pipe
(Option){6.35
(with heat insulator)
Refrigerant pipe
(Option){9.52
(with heat insulator)
Flared
connection
Flared
connection
Unit: mm
OB403B--1.qxp 07.6.26 10:28 AM Page 10

11
MU-A15ND Unit: mm
Strainer
#100
Muffler
Refrigerant pipe
(Option) [12.7
(with heat insulator)
Outdoor
heat
exchanger
Capillary tube
[3.0x[1.8x700
Refrigerant pipe
(Option) [6.35
(with heat insulator) Refrigerant flow in cooling
Stop valve
(with service port)
Compressor
Flared connection
Flared connection
Stop valve
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12
MAX.REFRIGERANT PIPING LENGTH
Model Piping size O.D : mm
Refrigerant piping : m
Gas
{9.52
{12.7
Liquid
{6.35
20
20
MU-A08ND
MU-A10ND
MU-A12ND
MU-A15ND
10
10
Max. length
AMax. height B
Indoor
unit
Max. Height
B
Outdoor unit
Refrigerant Piping
Max. Length
A
MAX.HEIGHT DIFFERENCE
ADDITIONAL REFRIGERANT CHARGE(R22 : g)
NOTE : Calculation : Xg=15g/m ✕ (Refrigerant piping length (m)-7)
Model Outdoor unit precharged Refrigerant piping length (one way)
15m 20m
195
7m 10m
120045
MU-A08ND
MU-A10ND -
MU-A10ND -
MU-A12ND
MU-A15ND
800
600
1100
1200
1600
C1
C2
PERFORMANCE CURVES7
The standard data contained in these specifications apply only to the operation of the air conditioner under normal conditions.
Since operating conditions vary according to the areas where these units are installed. The following information has been
provided to clarify the operating characteristics of the air conditioner under the conditions indicated by the performance curve.
(1) GUARANTEED VOLTAGE
198 ~ 253V, 60Hz
(2) AIR FLOW
Air flow should be set at MAX.
(3) MAIN READINGS
(1) Indoor intake air wet-bulb temperature : °CWB
(2) Indoor outlet air wet-bulb temperature : °CWB
(3) Outdoor intake air dry-bulb temperature : °CDB
(4) Total input: W
Indoor air wet/dry-bulb temperature difference on the left side of the chart on next page shows the difference between the
indoor intake air wet/dry-bulb temperature and the indoor outlet air wet/dry-bulb temperature for your reference at service.
MU-A08ND MU-A10ND MU-A12ND MU-A15ND
OB403B--1.qxp 07.6.26 10:28 AM Page 12

13
1Both indoor and outdoor units are under the same temperature/humidity condition.
OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT
COOL operation
2Air flow should be set at MAX.
Dry-bulb temperature (:)Relative humidity (%)
20 50
25 60
30 70
3The unit of pressure has been changed to MPa on the international system of units(SI unit system).
The conversion factor is : 1(MPa [Gauge]) =10.2(kgf/ff[Gauge])
Indoor intake air WB temperature (:)
Outdoor intake air DB temperature (:)
Indoor intake air WB temperature (:)
Outdoor intake air DB temperature (:)
MU-A10ND MS-A10ND
MU-A12ND MS-A12ND MS-A15ND MU-A15ND
4.8
4.3
5.4
7.0
6.5
5.9
MU-A08ND
5.4
4.8
6.0
7.9
7.3
6.6
7.5
6.7
8.4
11.2
10.2
9.3
8.5
7.5
9.5
12.8
11.6
10.5
MS-A08ND
Wet-and dry-bulb
thermometers
Wet and dry-bulb
thermometers
How to measure the indoor air wet/dry-bulb temperature difference
1. Attach at least 2 sets of wet and-dry-bulb thermometers to the indoor air intake as shown in the figure, and at least 2 sets
of wet and dry-bulb thermometers to the indoor air outlet. The thermometers must be attached to the position where air
speed is high.
2. Attach at least 2 sets of wet and dry-bulb thermometers to the outdoor air intake.
Cover the thermometers to prevent direct rays of the sun.
3. Check that the air filter is cleaned.
4. Open windows and doors of the room.
5. Press the EMERGENCY OPERATION switch once to start the EMERGENCY COOL MODE.
6. When system stabilizes after more than 15 minutes, measure temperature and take an average temperature.
7. 10 minutes later, measure temperature again and check that the temperature does not change.
INDOOR UNIT OUTDOOR UNIT
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14
15 18 20
50 25 60 30 70 35(:)
(%)
1.5
2.0
2.5
3.0
3.5
32
220V
5
6
7
8
415 18 20
50 25
60 30
70 32 35(:) (%)
0.4
0.5
0.6
0.7
0.8 220V
MU-A08ND MU-A08ND
Outdoor low pressure
Ambient temperature(˚C) Ambient humidity(%) Ambient temperature(˚C) Ambient humidity(%)
Outdoor unit current (A)
(kgf/F[Gauge])(MPa[Gauge])
15 20
50 25 60 30 70 35(:) (%)
0.3
0.4
0.5
0.6
0.7
7.0
6.0
5.0
4.0
3.0
220V
18 32
15 20
50
18 3225
60 30 70 35(:) (%)
3
4
5
6
220V
MU-A12ND MU-A12ND
Ambient temperature(˚C) Ambient humidity(%) Ambient temperature(˚C) Ambient humidity(%)
Outdoor low pressure
Outdoor unit current (A)
(kgf/F[Gauge])(MPa[Gauge])
15 20
50 25 60 30 70 35(:)
(%)
2.0
2.5
3.0
3.5
4.0
220V
18 32
15 20
50 25 60 30 70 35(:) (%)
0.4
0.5
0.6
0.7
0.8
220V
4.0
5.0
6.0
7.0
8.0
9.0 0.9
18 32
MU-A10ND MU-A10ND
Outdoor low pressure
Ambient temperature(˚C) Ambient humidity(%) Ambient temperature(˚C) Ambient humidity(%)
Outdoor unit current (A)
(kgf/F[Gauge])(MPa[Gauge])
15 3218 20
50 25 60 30 70 35(:) (%)
0.3
0.4
0.5
0.6
0.7
4
5
6
7
3
220V
15 18 20
50 25
60 30
70 35(:)
(%)
4.0
4.5
5.0
5.5
6.0
6.5
32
220V
MU-A15ND MU-A15ND
Ambient temperature(˚C) Ambient humidity(%) Ambient temperature(˚C) Ambient humidity(%)
Outdoor low pressure
Outdoor unit current (A)
(kgf/F[Gauge])(MPa[Gauge])
OB403B--1.qxp 07.6.26 10:28 AM Page 14

15
TROUBLESHOOTING8
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 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 components.
4) When connecting or disconnecting the connectors, hold the housing of the
connector. DO NOT pull the lead wires.
Lead wiring
Housing point
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
"Test point
diagram and
voltage".
Check of
wiring
diagram
of outdoor
unit.
Refer to
"Check of
remote controller
and receiver
P.C. board".
Left lamp
2-time flash
Cause:
Indoor unit
•Trouble of room
temperature/
indoor coil
thermistor
Left lamp
3-time flash
Cause:
Indoor unit
•Trouble of
indoor fan
motor
Check room
temperature
thermistor and
indoor coil thermistor.
Refer to
"Test point diagram
and voltage".
Refer to
"Check of
indoor fan
motor".
1. Check indoor /
outdoor
connecting wire.
2. Refer to
"Check of indoor
electronic control
P.C. board".
Left lamp
4-time flash
Cause:
Indoor unit
•Trouble of
indoor control
system
Replace the
indoor
electronic
control P.C.
board.
As for indoor unit,
refer to service
manual OB402.
Both lamps
(Left and right)
Flash on and off at
0.5-second intervals
Cause:
Indoor unit
•The horizontal vanes
are not installed
correctly.
Refer to "Check of
installation of the
horizontal vane".
8-2. Instruction of troubleshooting
MU-A08ND MU-A10ND MU-A12ND MU-A15ND
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Outdoor fan
motor (MF)
INNER
PROTECTOR
MU-A08ND
135i 5:OPEN
95i 15:CLOSE
MU-A15ND
130i 5:OPEN
83i 15:CLOSE
INNER FUSE
MU-A10/12ND
149i 3:OPEN
WHTRED
BLK
MAIN
AUX.
WHTRED
BLK
MAIN
AUX.
MU-A15ND
MU-A08ND
FUSE
WHTRED
BLK
MAIN
AUX.
MU-A10/12ND
ORN
Compressor
(MC)
OVERCURRENT
RELAY
MU-A08ND
150i 5:OPEN
78i9:CLOSE
INNER
PROTECTOR
MU-A10ND
150i 5:OPEN
90i10:CLOSE
MU-A12ND
155i 5:OPEN
90i10:CLOSE
MU-A15ND
155i 5:OPEN
90i10:CLOSE
8-3. Trouble criterion of main parts
Part name Check method and criterion Figure
R
C
SRED BLK
WHT
MAINAUX.
R
C
S
RED BLK
WHT
MAINAUX. P
MU-A10/12/15ND
MU-A08ND
PP:INNER PROTECTOR
Measure the resistance between the terminals with a tester.
(Coil wiring temperature -10°C ~ 40°C)
Color of
lead wire Normal
WHT-BLK
BLK-RED 102 ~ 126 "
97 ~ 120 "
MU-A15ND
132 ~ 162 "
233 ~ 286 "
MU-A08ND 338 ~ 414 "
228 ~ 280 "
MU-A10ND 275 ~ 337 "
224 ~ 276 "
MU-A12ND
Measure the resistance between the terminals with a tester.
(Coil wiring temperature -10°C ~ 40°C)
Color of
lead wire Normal
MU-A12ND
1.0 ~ 2.37 "
2.0 ~ 3.56 "
MU-A15ND
1.32 ~ 1.61 "
2.06 ~ 2.51 "
C-R
C-S
MU-A08ND
3.61 ~ 4.41 "
4.93 ~ 6.01 "
MU-A10ND
2.0 ~ 2.96 "
3.0 ~ 4.25 "
MU-A08ND MU-A10ND MU-A12ND MU-A15ND
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DISASSEMBLY INSTRUCTIONS
9
(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
9-1. MU-A08ND
OUTDOOR UNIT
OPERATING PROCEDURE PHOTOS
1. Removing the cabinet
(1) Remove the screws of the top panel.
(2) Remove the screws of the service panel.
(3) Remove the screw of the valve cover (MU-A08ND- ).
(4) Remove the screws of the cabinet.
(5) Remove the screws of the front panel and motor support.
(6) Remove the service panel, and remove the screw from
the inside.
(7) Remove the valve cover (MU-A08ND- ).
(8) Remove the top panel.
(9) Remove the cabinet.
C2
C2
Photo 1
Photo 3
Screws of the
top panel
Service
panel
Screws of the
service panel
Screws of
the top panel
Screws of
the cabinet
Screws of the cabinet
Photo 2
Screws of the front panel
and motor support
Screws
of the
cabinet
Photo : MU-A08ND - C2
Photo : MU-A08ND - C2
Screw
of the
valve
cover
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Compressor
capacitor (C1)
OPERATING PROCEDURE PHOTOS
2. Removing the electrical parts
(1) Remove the service panel and the cabinet.(Refer to 1.)
(2) Remove the following parts.
•Compressor capacitor (C1)
•Outdoor fan capacitor (C2)
•Terminal block (TB)
Photo 6
Compressor
Terminal
cover
3. Removing the propeller and the outdoor fan motor
(1) Remove the cabinet. (Refer to 1.)
(2) Remove the propeller nut.
(3) Remove the propeller .
NOTE : Loose the propeller in the rotating direction for
removal.
When attaching the propeller, align the mark on the
propeller and the motor shaft cut section.
Set the propeller in position by using the cut on the
shaft and the mark on the propeller.
(4) Remove the lead clamps and the outdoor fan motor lead
wires.
(5) Remove the screws fixing the outdoor fan motor.
(6) Remove the outdoor fan motor.
Photo 5
Suction pipe
Discharge pipe
Compressor
nuts
4. Removing the compressor
(1) Remove the cabinet. (Refer to 1.)
(2) Remove the relay panel.
(3) Remove the soundproof felt.
(4) Remove the terminal cover on the compressor.
(5) Disconnect lead wires from the glass terminal of the com-
pressor.
(6) Recover gas from the refrigerant circuit.
NOTE : Recover gas from the pipes until the pressure gauge
shows 0 kg/cm2(0MPa).
(7) Disconnect the welded part of the discharge pipe
(8) Disconnect the welded part of the suction pipe.
(9) Remove the nuts fixing the compressor.
(
10
)Remove the compressor.
Glass
terminal
Photo 4 Outdoor fan
capacitor (C2)
Terminal block
Lead
clamp
Propeller Propeller nut
Outdoor
fan motor Set screws of outdoor fan motor
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9-2. MU-A10ND
OUTDOOR UNIT
OPERATING PROCEDURE PHOTOS
1. Removing the cabinet
(1) Remove the screws fixing the top panel.
(2) Remove the top panel.
(3) Remove the screw fixing the service panel.
(4) Pull down the service panel and remove it.
(5) Remove the screws fixing the cabinet.
(6) Remove the cabinet.
(7) Disconnect the indoor/ outdoor connecting wire.
(8) Remove the screws fixing the back panel.
(9) Remove the back panel.
Photo 1
Photo 3
Screws of
the top panel
Screws of
the cabinet
Screws of the cabinet
Photo 2
Screws of the front panel and motor support
Screws of the
top panel
Service
panel
Screw of the
cabinet
Direction
to remove
Hooks
Screw of the
service panel
2. Removing the electrical parts
(1) Remove the service panel and the cabinet. (Refer to 1.)
(2) Remove the following parts.
•Compressor capacitor (C1)
•Outdoor fan capacitor (C2)
•Terminal block (TB)
Photo 4
Outdoor fan capacitor (C2)
Compressor capacitor (C1)
Terminal block (TB)
Photo : MU-A10ND - C1
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Glass
terminal
OPERATING PROCEDURE PHOTOS
3. Removing the propeller and the outdoor fan motor
(1) Remove the cabinet. (Refer to 1.)
(2) Remove the propeller nut and the propeller.
NOTE : Loose the propeller in the rotating direction for
removal.
When attaching the propeller, align the mark on the
propeller and the motor shaft cut section.
Set the propeller in position by using the cut on the shaft
and the mark on the propeller.
(3) Remove the lead clamps and outdoor fan motor lead wires.
(4) Remove the screws fixing the outdoor fan motor.
(5) Remove the outdoor fan motor.
Photo 5
Propeller
Propeller
nut Outdoor
fan motor
Set screws of the
outdoor fan motor Hook Relay panel
Outdoor fan motor lead wires
Set screws of the
outdoor fan motor
4. Removing the compressor
(1) Remove the cabinet. (Refer to 1.)
(2) Remove the screws fixing the relay panel.
(3) Remove the soundproof felt.
(4) Remove the terminal cover.
(5) Pull out the lead wires from the glass terminal of the com-
pressor.
(6) Recover gas from the refrigerant circuit.
NOTE : Recover gas from the pipes until the pressure gauge
shows 0 kg/cm2(0MPa).
(7) Disconnect the welded part of the suction pipe and
discharge pipe.
(8) Remove the nuts fixing the compressor.
(9) Remove the compressor.
Photo 6
Compressor
Suction pipe
Discharge pipe
Compressor
nuts
Photo : MU-A10ND - C1
Photo : MU-A10ND - C1
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