Mitsubishi Electric Mr.Slim MU-A18ND-S1 User manual

CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················3
3. SPECIFICATION·················································3
4. OUTLINES AND DIMENSIONS ·························4
5. WIRING DIAGRAM ············································6
6. REFRIGERANT SYSTEM DIAGRAM ················8
7. PERFORMANCE CURVES······························10
8. TROUBLESHOOTING······································12
9. DISASSEMBLY INSTRUCTIONS ····················21
10. PARTS LIST······················································27
11. RoHS PARTS LIST···········································30
SPLIT-TYPE AIR CONDITIONERS
TM
MU-A18ND
MU-A18ND-
MU-A18ND-
MU-A24ND-
MU-A24ND-
MU-A30ND-
MU-A30ND- S2
S1
S2
S1
S2
S1
Indoor unit service manual
MS-A• ND Series (OB404)
No. OB405
REVISED EDITION-E
SERVICE MANUAL
Models
OUTDOOR UNIT
NOTE:
• This service manual describes technical data of the 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.
Please void OB405 REVISED EDITION-D.
Revision E:
•SPECIFICATION has been modified.
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2
TECHNICAL CHANGES1
2
Compressor: NH30VCD ➞ RH247NRAT
Compressor: RH277NHD
➞ RH247NRAT
Electricity receiving unit: Indoor unit ➞ Outdoor unit
Gas pipe diameter: [15.88
➞ [12.7
Rated voltage: 220V ➞ 220-230V
Frequency
New Model
Old Model
MU-18TN -
S1
w : change
MU-A18ND -
S1
60Hz
MU-18SN -
C1
w
w
w
w
w
w
w
w
Outdoor unit:Unit size:W850mmoH605mmoD290mm ➞ W840mmoH850mmoD330mm
Outdoor unit:Unit size:W870mmoH850mmoD295mm ➞ W840mmoH850mmoD330mm
Compressor: NH38NBD ➞ PH33NPBT
Electricity receiving unit: Indoor unit ➞ Outdoor unit
Liquid refrigerant pipe diameter: [9.52
➞ [6.35
Rated voltage: 220V ➞ 220-230V
Frequency
New Model
Old Model
MU-24TN -
S1
MU-A24ND -
S1
60Hz
MU-24SN -
C2
w
w
w
w
w
w
w
w
w
w
MU-A30ND -
New model
S1
MU-A18ND -➔MU-A18ND -
• Valve cover has been added.
S2S1
MU-A24ND -➔MU-A24ND -
• Compressor contactor has been added.
S2S1
MU-A30ND -➔MU-A30ND -
• Solenoid valve and solenoid valve coil have been changed.
S2S1
Revision A:
• Check of solenoid valve coil has been partially modified.
Revision B:
• MU-A24ND -has been added.
S2
Revision C:
• MU-A18ND -has been added.
S2
Revision D:
• MU-A30ND -has been added.
S2
Revision E:
• SPECIFICATION has been modified.
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3
PART NAMES AND FUNCTIONS
2
SPECIFICATION
3
Outdoor model
Function
Power supply
Capacity
Dehumidification
Air flow (High/Low)
Power outlet
Running current (Total)
Power input (Total)
Power factor (Total)
Starting current (Total)
Compressor motor current
Fan motor current
Model
Output
Winding
resistance (at 20:)
Model
Winding
resistance (at 20:)
Dimensions WOHOD
Weight
Sound level (High/Low)
Fan speed (High/Low)
Fan speed regulator
Refrigerant filling
capacity (R22)
Refrigeration oil (Model)
kW
R/h
K/h
A
A
W
%
A
A
A
W
"
"
mm
kg
dB
rpm
kg
cc
Cooling
Single phase
220-230V, 60Hz
2,880
58
0.66
PH33NPBT
1,500
C-R 0.84
C-S 2.09
RA6N75-BA
WHT-BLK 65.0
BLK-RED 65.4
67
54
790
1
2.20
900 (MS32N1)
Electrical data
Compressor
Fan motor
Special remarks
Coefficient of performance (C.O.P) (Total)
Capacity
2,480
15
40
0.55
RH247NRAT
1,200
C-R 1.43
C-S 2.06
RA6V60-MA
WHT-BLK 71.2
BLK-RED 89.3
850o605o290
44
54
945
1
1.40
520 (MS56)
ISO 5151
5.10
2.3
8.52
1,800
96-92
7.60
2.83
SSA 385
5.9
2.7
20( )
12.42
2,650
97
11.39
2.23
ISO 5151
6.6
3.2
15( )
10.54
2,250
97-93
9.50
2.93
SSA 385
6.6
3.2
17.52
3,700
96
16.49
1.78
ISO 5151
8.1
4.3
14.25
3,010
96-92
13.22
2.69
SSA 385
4.40
1.8
9.94
2,100
96
9.02
2.10
MU-A24ND MU-A30ND
2,880/1,380
25
78
0.66
NH44NAVT
2,000
C-R 0.62
C-S 1.40
RA6N75-AA
WHT-BLK 64.2 BLK-YLW 32.9
YLW-RED 32.7
76
55/51
790/490
2
2.40
1,300 (MS32N1)
840o850o330
S2
S1
MU-A18ND
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
OUTDOOR UNIT
Air inlet
Air outlet
Drain outlet
Piping
Drain hose
Air inlet
Air outlet
(back and side)
MU-A18ND MU-A24ND MU-A30ND
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4
OUTLINES AND DIMENSIONS4
Unit: mm
100mm or more
350mm or more
100mm or more
100mm or more
REQUIRED SPACE
500mm or more
100
157
161
Liquid refrigerant
pipe joint
Refrigerant pipe
(Flared) [6.35
Service panel
183
500
850
30
50
20350
35
248
605
292
20
310 290
345
Air in
Air out
Drainage
3holes [33
50
90
Air in
Drainage
hole [16.2
355
74
30-
35-
Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [12.7
MU-A18ND - S1
OUTDOOR UNIT
100
157
161
Liquid refrigerant
pipe joint
Refrigerant pipe
(Flared) [6.35
Service panel
183
500
850
30
50
20350
35
248
605
292
20
310 290
345
Air in
Air out
Drainage
3holes [33
50
90
Air in
Drainage
hole [16.2
355
81
74
30-
35-
Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [12.7
100mm or more
350mm or more
100mm or more
100mm or more
REQUIRED SPACE
500mm or more
MU-A18ND - S2
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5
30-
35-
155
90
198
40
515
299
66
34
51
330
360
850
430
500
80
121
840
REQUIRED SPACE Open as a rule
500mm or more if
the front and both
sides are open
100mm or more
200mm or more if
there are obstacles
to both sides
Open as a rule
500mm or more if the back,
both sides and top are open
Service panel
Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [15.88
Liquid refrigerant
pipe joint
Refrigerant pipe
(flared) [6.35(MU-A24ND)
[9.52(MU-A30ND)
350mm or more
100mm or more
MU-A24ND MU-A30ND
OUTDOOR UNIT
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6
WIRING DIAGRAM
5
MU-A18ND
R
S
2
N
L
TB2
RED
ORN
BLU
BRN
WHT
GRN/YLW
C2
RED
MF
BLACK
4
WHITE
ORANGE
321
BLK
L
N
TB1
BRN
BLU C1 RED
C
MC
BLU
220-230V~
CONNECTING
TO INDOOR UNIT
POWER SUPPLY
220-230V ~/N 60Hz
F
BLU
DSAR
220-230V~
WHT
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.
: Connector
: Terminal block,
NOTES:
SYMBOL
C1
C2
DSAR
SYMBOL
F
MC
MF
SYMBOL
TB1
TB2
NAME NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER
FUSE (3.15A)
COMPRESSOR(INNER PROTECTOR)
OUTDOOR FAN MOTOR(INNER PROTECTOR)
TERMINAL BLOCK
TERMINAL BLOCK
MU-A24ND- S1
L
N
2
BRN
RED
BLK
WHT
BLU
TB2
BLU
WHT
RED
C2
ORN
DSAR
TB1
GRN/YLW
BRN
F
MF
2
1
ORN
RED
3
4
N
L
PE
BLU
MC
WHT
BLU SC
R
C1
BLK
SYMBOL
C1
C2
DSAR
SYMBOL
F
MC
MF
SYMBOL
TB1
TB2
NAME NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER
FUSE(3.15A)
COMPRESSOR(INNER PROTECTOR)
OUTDOOR FAN MOTOR(INNER PROTECTOR)
TERMINAL BLOCK
TERMINAL BLOCK
NOTES: 1.Use copper conductors only (For field wiring).
2.Since the indoor and outdoor unit connecting wires have polarity, connect them according to the numbers (2,N,L).
3.Symbols below indicate.
: Terminal block, : Connector
TO INDOOR UNIT CONNECTING
220-230V~
220-230V~
POWER SUPPLY
~/N 220-230V 60Hz
OUTDOOR UNIT
OUTDOOR UNIT
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7
MU-A30ND
SYMBOL
C1
C2
DSAR
F61
LEV
MC
MF
SYMBOL
NR61
RT62
RT63
SR61
SR62
TB1
TB2
SYMBOL
T61
X52
X63
21S2
52C
NAME
DEICER
P.C. BOARD
2
N
3
N
L
12V
WHT
BLU
RED
BLU
WHT
WHT
T61
YLW
BLK WHT
RED
BLU
TB2
5
CN730
YLW
BLK WHT
1
52C
2
RED
C2
ORN
A1 A2BLU 52C
DSAR
WHT
C1
BLK
S
C
R
MC
BLU
NR61
3
1
TB1
GRN/YLW
BRN
SR62
SR61
F61
TAB52
COM NO
X52
CN711
CN724
CN662
6
MF
RT62 RT63
123
21
ORN RED
3456
LEV
COM NO
X63 3
2
1
CN722
X52
PE
220-230V~
TO INDOOR UNIT CONNECTING
POWER SUPPLY
~/N 220-230V 60Hz
X63
21S2
NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER
FUSE(3.15A)
EXPANSION VALVE COIL
COMPRESSOR(INNER PROTECTOR)
OUTDOOR FAN MOTOR(INNER PROTECTOR)
VARISTOR
DISCHARGE TEMPERATURE THERMISTOR
AMBIENT TEMPERATURE THERMISTOR
SOLID STATE RELAY
SOLID STATE RELAY
TERMINAL BLOCK
TERMINAL BLOCK
TRANSFORMER
CONTACTOR
SOLENOID VALVE COIL RELAY
SOLENOID VALVE COIL
COMPRESSOR CONTACTOR
NOTES: 1.Use copper conductors only (For field wiring).
2.Since the indoor and outdoor unit connecting wires have polarity, connect them according to the numbers (3,N,2).
3.Symbols below indicate.
: Terminal block, : Connector
MU-A24ND- S2
OUTDOOR UNIT
OUTDOOR UNIT
SYMBOL
C1
C2
DSAR
SYMBOL
F
MC
MF
SYMBOL
TB1
TB2
52C
NAME NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER
FUSE(3.15A)
COMPRESSOR(INNER PROTECTOR)
OUTDOOR FAN MOTOR(INNER PROTECTOR)
TERMINAL BLOCK
TERMINAL BLOCK
COMPRESSOR CONTACTOR
NOTES: 1.Use copper conductors only (For field wiring).
2.Since the indoor and outdoor unit connecting wires have polarity, connect them according to the numbers (2,N,L).
3.Symbols below indicate.
: Terminal block, : Connector
BLK
WHT
ORN
BLU
WHT
ORN
RED
BLK
WHT
BLU
BLU BLU
WHT
BRN
52C
GRN/YLW
BLU
BRN
BRN
C2
C1
TO INDOOR UNIT CONNECTING
220-230V~
220-230V~
POWER SUPPLY
~/N 220-230V 60Hz
56
DSAR
L
N
2
N
L
TB2
TB1
MF
MC
4
52C
1
R
S
C
RED RED
F
4
3
2
1
PE
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8
REFRIGERANT SYSTEM DIAGRAM6
MU-A24ND
OUTDOOR UNIT
Outdoor
heat
exchanger
Flared connection
Flared connection
Stop valve
Stop valve
(with service port)
Capillary tube
[3.0 x [2.0 x 550
Refrigerant flow in cooling
Compressor
Refrigerant pipe
[15.88
(with heat insulator)
Refrigerant pipe
[6.35
(with heat insulator)
Strainer
#100
Accumulator
MU-A18ND
OUTDOOR UNIT
Unit : mm
Refrigerant pipe
{6.35
(with heat insulator)
Refrigerant pipe
{12.7
(with heat insulator)
Compressor
Outdoor heat
exchanger
Flared
connection
Strainer
#100
Stop Valve
(with service port)
Stop Valve Capillary tube
[3.0 x [1.8 x 400
OB405E.qxp 09.10.14 9:16 AM Page 8

9
Outdoor
heat
exchanger
Flared connection Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
Stop valve
(with service port)
Capillary tube
[3.6 x [2.4 x 50
Refrigerant flow in cooling
Compressor
Refrigerant pipe
[15.88
(with heat insulator)
Refrigerant pipe
[9.52
(with heat insulator)
Strainer
#100
Strainer
#100
Accumulator
Ambient
temperature
thermistor
RT63
Capillary tube
[4.0 x [2.4 x 200
Capillary tube
[4.0 x [2.4 x 100
LEV
(Expansion valve)
Solenoid valve
[4.2 x [3.0 x 50
MU-A30ND
OUTDOOR UNIT
MAX.REFRIGERANT PIPING LENGTH and MAX.HEIGHT DIFFERENCE
Model
Piping size O.D : mm
Refrigerant piping : m
Max. length
A
Max. Height
difference
B
Gas Liquid
30
MU-A18ND
MU-A24ND
MU-A30ND
{15.88
{6.35
{9.52
15
{12.7
Indoor
unit
Outdoor unit
Max. length
A
Max. Height
difference
B
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
120
20m
195
30m
345
7m
0
10m
45
2,200
1,400
2,400
MU-A18ND
MU-A30ND
MU-A24ND
Unit : mm
OB405E.qxp 09.10.15 1:32 PM Page 9

10
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 following chart 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-A18ND MU-A24ND MU-A30ND
Indoor intake air WB temperature (:)
Outdoor intake air DB temperature (:)
Indoor intake air WB temperature (:)
Outdoor intake air DB temperature (:)
MS-A30ND MU-A30ND MS-A24ND MU-A24ND MS-A18ND MU-A18ND
9.9
9.1
8.3
7.5
6.7
5.9
12.5
11.4
10.3
9.3
8.3
7.3
18.6
16.8
15.1
13.5
12.0
10.5
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
OB405E.qxp 09.10.14 9:16 AM Page 10