Mitsubishi Electric MSC-A07YV-E1 User manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································3
2. PART NAMES AND FUNCTIONS······················3
3. SPECIFICATION·················································5
4. NOISE CRITERIA CURVES·······························6
5. OUTLINES AND DIMENSIONS ·························7
6. WIRING DIAGRAM ············································8
7. REFRIGERANT SYSTEM DIAGRAM················8
8. MICROPROCESSOR CONTROL ······················9
9. SERVICE FUNCTIONS ····································17
10. TROUBLESHOOTING······································19
11. DISASSEMBLY INSTRUCTIONS·····················26
12. PARTS LIST······················································28
Wireless type
Models
MSC-A07YV - (WH)
MSC-A09YV - (WH)
MSC-A12YV - (WH)
E1
E1
E1
MSC-A07YV -
MSC-A09YV -
MSC-A12YV - E1
E1
E1
No. OB329
HFC
utilized
R410A
SPLIT-TYPE, AIR CONDITIONERS
SPLIT-TYPE, HEAT PUMPAIR CONDITIONERS
Indication of model name
NOTE:
•This manual describes technical data of indoor units.
•As for outdoor units MU-A07/A09/A12YV - , refer to the service manual OB330.
•As for outdoor units MUH-A07/A09/A12YV - , refer to the service manual OB331.
•As for outdoor units MUX-A10/A19/A20/A25/A26WV - , refer to the service manual OB307 REVISED
EDITION-A.
•As for outdoor units MUX-A22WV - , refer to the service manual OB318.
•As for outdoor units MXZ-A18/A26/A32WV - , refer to the service manual OB319.
E1
E1
E1
E1
E1
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3
PART NAMES AND FUNCTIONS
2
INDOOR UNIT
MSC-A07YV -
MSC-A09YV -
MSC-A12YV - E1
E1
E1
Emergency operation switch
Fan
Catechin air filter
(With deodorizer)
Air outlet
Vertical vanes
Air inlet
to Breaker
Remote control
receiving section
Display section
Air cleaning filter
(white bellows type) Front panel
Power supply cord
Panel
Horizontal vane
Operation section
(When the front panel is opened)
Remote controller
Operation indicator lamp
Remote control
receiving section
TECHNICAL CHANGES
1
MSC-A07WV- ➔MSC-A07YV-
MSC-A09WV- ➔MSC-A09YV-
MSC-A12WV- ➔MSC-A12YV-
1. Design of front panel has changed.
2. Air filter has changed to the catechin air filter.
E1E1
E1E1
E1E1
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4
ACCESSORIES
MSC-A07YV-
MSC-A09YV-
MSC-A12YV- E1
E1
E1
Installation plate
Installation plate fixing screw 4 o25 mm
Remote controller holder
Fixing screw for 33.5 o16 mm
Battery (AAA) for remote controller
Wireless remote controller
Felt tape (Used for left or left-rear piping)
Air cleaning filter
1
5
1
2
2
1
1
1
<Indoor unit>
1
2
3
4
5
6
7
8
ON/OFF
FAN
TOO
WARM TOO COOL
VANE
MODE
ECONO COOL
STOP
START
HR.
MIN.
I FEEL COOL
DRY
PM
CLOCK
AM
RESET CLOCK
HEAT
/FAN
/
Open the front lid.
ON/OFF
TOO
COOL
PM
AM
TOO
WARM
Signal transmitting section
Operation display section
OPERATE /STOP
(ON /OFF)button
TEMPERATURE buttons
Indication of remote controller model is
on back.
OPERATION SELECT button
FAN SPEED CONTROL button OFF-TIMER button
HR. button
MIN. button
(TIME SET button)
ON-TIMER button
RESET button
ECONO COOL button
VANE CONTROL button
CLOCK SET button
REMOTE CONTROLLER
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5
SPECIFICATION
3
Indoor model
Function
Indoor unit power supply
Air flow(High/Med. /Low )
Power outlet
Running current
Power input
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
K/h
A
A
W
%
A
"
mm
kg
dB
rpm
k"
k"
MSC-A07YV - E1
Single phase
230V,50Hz
10
0.17
35
90
0.17
RC4V19-LA
WHT-BLK 413
BLK-RED 334
815O278O244
9
5
3
10
10
KP1A or KG3A
Cooling
474/372 /276
36/31 /25
900/750 /600
Heating
510/420 /342
36/31 /25
950/820 /700
MSC-A09YV - E1
Single phase
230V,50Hz
10
0.17
35
90
0.17
RC4V19-LA
WHT-BLK 413
BLK-RED 334
815O278O244
9
5
3
10
10
KP1A or KG3A
Cooling
474/384 /306
36/31 /25
900/770 /650
Heating
588/456 /342
39/32 /25
1,050/870 /700
MSC-A12YV - E1
Single phase
230V,50Hz
10
0.19
40
92
0.19
RC4V19-KA
WHT-BLK 316
BLK-RED 299
815O278O244
10
5
3
10
10
KP1A or KG3A
Cooling
582/444 /324
40/33 /26
930/760 /600
Heating
606/498 /396
39/33 /26
960/830 /700
Electrical data
Fan motor
Special remarks
Capacity
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NOTE: 1. Test conditions are based on ISO 5151.
Cooling : Indoor DB27°C WB19°C Heating : Indoor DB20°C
Outdoor DB35°C WB24°C OutdoorDB 7°C/WB 6°C
Indoor-Outdoor piping length 5m
2.Remote controller model KP1A and KG3A are the same in terms of specification.
WReference value
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6
NOISE CRITERIA CURVES
4
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : DB27:WB19:
Heating : DB20:WB -:
MSC-A07YV- E1 COOL
High
FUNCTIONFAN SPEED
36
HEAT
SPL(dB(A)) LINE
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions.
Cooling : DB27:WB19:
Heating : DB20:WB -:
MSC-A09YV- E1 COOL
High
FUNCTIONFAN SPEED
36
HEAT 39
SPL(dB(A)) LINE
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
Test conditions,
Cooling : DB27:WB19:
MSC-A12YV- E1 COOL
FUNCTIONFAN SPEED
40
HEAT
High 39
SPL(dB(A)) LINE
INDOORUNIT WALL
MICROPHONE
0.8m
1m
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7
OUTLINES AND DIMENSIONS
5
MSC-A07YV -
MSC-A09YV - E1
E1
INDOOR UNIT
244
242 5
7 or more
90
110
30
149
606
278
60
815
783
Power supply cord
Lead to right 1.0m
Lead to left 0.3m
Air out
Installation plate
Insulation [28
Drain hose [16
(Connected part O,D)
Air in Liquid line [6.35-0.5m
Gas line [9.52-0.43m
Insulation [37 O.D
[21 I.D
{
Wireless remote controller
162
19
58
81.5
81.5
41
2.5
42
271
231.5
4.5
81.5 133.5
326326
Wall hole [65
Indoor unit
Installation plate
Unit: mm
MSC-A12YV - E1
INDOOR UNIT
244
242
218.5
258
81.581.5
41
42
2.5
17.5
161.5161.5
326326
5
7 or more
90
110
30
149
606
278
60
815
783
Power supply cord
Lead to right 1.0m
Lead to left 0.3m
Air out
Indoor unit
Installation plate
Wall hole [65
Installation plate
Insulation [28
Drain hose [16
(Connected part O,D)
Air in
Liquid line [6.35-0.5m
Gas line [9.52-0.43m
Insulation [37 O.D
[21 I.D
{
Wireless remote controller
162
19
58
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8
REFRIGERANT SYSTEM DIAGRAM
7
MSC-A07YV - MSC-A09YV - E1E1 MSC-A12YV - E1
INDOOR UNIT INDOOR UNIT
Indoor
heat
exchanger
Room temperature
thermistor
RT11
Refrigerant pipe [9.52
(with heat insulator)
Unit:mm
Refrigerant pipe [12.7
(with heat insulator)
Refrigerant pipe [6.35
(with heat insulator)
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT12
Indoor coil
thermistor
RT12
Indoor
heat
exchanger
Flared connection
Flared connection
Flared connection
Flared connection
WIRING DIAGRAM
6
MSC-A07YV - MSC-A09YV - MSC-A12YV - E1E1E1
MODELS WIRING DIAGRAM
SYMBOL
NR11
RT11
RT12
SR141
NAME NAME NAME
INDOOR FAN CAPACITOR
FUSE(3.15A)
INDOOR FAN MOTOR (INNER FUSE)
VANE MOTOR
VARISTOR
ROOM TEMPERATURE THERMISTOR
INDOOR COIL THERMISTOR
SOLID STATE RELAY
TERMINAL BLOCK
SYMBOL
C11
F11
MF
MV
SYMBOL
TB
T11 TRANSFORMER
CIRCUIT BREAKER
SR141 C11
RED
WHT
3
6
5
BRN
YLW
GRY
BLK
4
3
2
1
MF
121
CN
1
3
5
111
CN
112
CN RT12
RT11
NR11
F11
ELECTRONIC CONTROL P.C. BOARD
CN211
TAB12
CN201
3
2
1
CN202
2
1
151
CN
55
BRN
RED
BLU
WHT
BLK
BLU
BRN
TB
L
3
N
2
1
12V
TO OUTDOOR
UNIT
CONNECTING
POWER
SUPPLY
CORD
~/N 230V
50Hz
GRN/YLW
POWER MONITOR,
RECEIVER
P.C.BOARD
REMOTE
CONTROLLER
MV
FOR
MUH OR
MXZ TYPE
FOR
MU OR
MUX TYPE
12V
PE
101
CN
T11
GRN
LD103
INDOOR UNIT
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
Refrigerant pipe [6.35
(with heat insulator)
Refrigerant flow
in cooling Refrigerant flow
in cooling
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9
MICROPROCESSOR CONTROL
8
ON/OFF
FAN
TOO
WARM TOO COOL
VANE
MODE
ECONO COOL
STOP
START
HR.
MIN.
I FEEL COOL
DRY
PM
CLOCK
AM
RESET CLOCK
HEAT
/FAN
/
Open the front lid.
ON/OFF
TOO
COOL
PM
AM
TOO
WARM
Signal transmitting section
Operation display section
OPERATE /STOP
(ON /OFF)button
TEMPERATURE buttons
OPERATION SELECT button
FAN SPEED CONTROL button OFF-TIMER button
HR. button
MIN. button
(TIME SET button)
ON-TIMER button
RESET button
ECONO COOL button
VANE CONTROL button
CLOCK SET button
WIRELESS REMOTE CONTROLLER
Once the operation mode are set, the same operation mode can be repeated by simply turning the OPERATE/STOP
(ON/OFF) button ON. Indoor unit receives the signal with a beep tone.
When the system turns off, 3-minute time delay will operate to protect system from overload and compressor will not restart for
3 minutes.
MSC-A07YV -
MSC-A09YV -
MSC-A12YV - E1
E1
E1
lighted
not lighted
Approx. 2 : 
or more
Difference
between target
temperature
and room
temperature
Approx. 2 : 
or less
This shows that the
air conditioner is
operating to reach
the target temperature.
Please wait until the
target temperature is
obtained.
This shows that the
room temperature is
approaching the
target temperature.
Operation stateIndication
Operation Indicator
Operation Indicator lamp
The operation indicator at the right side of the indoor
unit indicates the operation state.
INDOOR UNIT DISPLAY SECTION
• The following indication does not
depend on the shape of lamp.
8-1. COOL ( ) OPERATION
(1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select COOL mode with the OPERATION SELECT button.
(3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button)to select the desired temperature.
The setting range is 16 ~ 31°C
1 deg. 1.7 deg. 3 deg.
2. Indoor fan speed control
Indoor fan operates continuously at the set speed by FAN SPEED CONTROL button regardless
of thermostat’s OFF-ON.
In Auto the fan speed is as follows. Initial temperature difference
Room temperature minus set temperature : 1.7 degrees or more·······························High
Room temperature minus set temperature : Between 1 and 1.7 degrees···················Med.
Room temperature minus set temperature : less than 1 degree··································Low
Fan speed Difference between room
temperature and set tem-
perature during operation
-0.3 :0.3 :
1. Thermostat control
Thermostat is ON or OFF by difference between room temperature and set temperature
Initial temperature difference Thermostat
Room temperature minus set temperature : 0.3 :or more················································ON
Room temperature minus set temperature : less than -0.3 :············································OFF
Set temperature
Difference between room
temperature and set tem-
perature during operation
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10
Compressor
Outdoor fan OFF
ON
( continuously at set speed)
Indoor fan ON
ON
OFF
② Time control
When the three conditions as follows have been satisfied for 1 hour and 45 minutes, the compressor stops for 3 minutes.
The indoor fan operates at the set speed.
a. Compressor has been continuously operating.
b. Indoor fan speed is Low or Med.
c. Room temperature is below 26°C.
When compressor stops, the accumulated time is cancelled. When compressor restarts, time counting starts
from the beginning.
Time counting also stops temporarily when the indoor fan speed becomes High or the room temperature exceeds
26°C. However, when two of the above conditions (b.and c.) are satisfied again, time accumulation is resumed.
Operation chart
Example
8-2. DRY ( ) OPERATION
(1) Press OPERATE/STOP(ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select DRY mode with the OPERATION SELECT button.
(3) The microprocessor reads the room temperature and determines the set tem-
perature. Set temperature is as shown on the right chart.
DRY operation will not function when the room temperature is 13°C or below.
(4) When DRY operation functions the fan speed is lower than COOL operation
except at (fan speed) Low.
The system for dry operation uses the same refrigerant circuit as the cooling
circuit.
The compressor and the indoor fan are controlled by the room temperature.
35
30
25
20
15
10
:
10 15 20 25 30 35
Set temperature
Initial room temperature
Set temperature and
initial room temperature in dry mode
:
2. Indoor fan speed control
Indoor fan operates at the set speed by FAN SPEED CONTROL button.
In Auto fan speed becomes Low.
3. The operation of the compressor and indoor / outdoor fan
<MU-A07/A09/A12YV, MUH-A07/A09/A12YV, MUX-A10/A19/A20/A22/A25/A26WV>
Compressor operates by room temperature control and time control.
Indoor fan and outdoor fan operate in the same cycle as the compressor.
●When the room temperature is 23°C or over:
When the thermostat is ON, the compressor repeats 8 minutes ON and 3 minutes OFF.
When the thermostat is OFF, the compressor repeats 4 minutes OFF and 1 minute ON.
●When the room temperature is under 23°C.
When the thermostat is ON, the compressor repeats 2 minutes ON and 3 minutes OFF.
When the thermostat is OFF, the compressor repeats 4 minutes OFF and 1 minute ON.
3. Coil frost prevention
① Temperature control
When the indoor coil thermistor RT12 reads 4°C or below(MSC-A07/A09YV) / 0°C or below(MSC-A12YV) for 5 minutes, the
coil frost prevention mode starts.
The indoor fan operates at the set speed and the compressor stops for 5 minutes.
After that, if RT12 still reads below 4°C (MSC-A07/A09YV) / 0°C (MSC-A12YV), this mode is prolonged until the RT12
reads over 4°C (MSC-A07/A09YV) / 0°C (MSC-A12YV).
-0.3 :0.3 :
1. Thermostat control
Thermostat is ON or OFF by difference between room temperature and set temperature.
Initial temperature difference Thermostat
Room temperature minus set temperature : 0.3 :or more················································ON
Room temperature minus set temperature : less than -0.3 :············································OFF
Set temperature
Difference between room
temperature and set tem-
perature during operation
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