Mitsubishi Electric Mr. Slim MS-A09WA User manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················3
3. SPECIFICATION·················································5
4. OUTLINES AND DIMENSIONS ·························6
5. WIRING DIAGRAM ············································7
6. REFRIGERANT SYSTEM DIAGRAM················7
7. SERVICE FUNCTIONS ······································8
8. TROUBLESHOOTING········································9
9. DISASSEMBLY INSTRUCTIONS ····················21
10. PARTS LIST······················································24
10-1. PARTS LIST··············································24
10-2. RoHS PARTS LIST···································27
11. MICROPROCESSOR CONTROL·····················30
Wireless type
Models
MS-A09WA
MS-A09WA -
MS-A12WA
MS-A12WA - 1
1
SPLIT-TYPE AIR CONDITIONERS
NOTE:
RoHS compliant products have <G> mark on the spec name plate.
For servicing of RoHS compliant products, refer to the RoHS PARTS
LIST (RoHS compliant).
INDOOR UNIT
Outdoor unit service manual
MU-A•WA Series (OB449)
Revision A:
• MS-A•WA-have been added.
1
Please void OB448.
No. OB448
REVISED EDITION-A
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MS-A09WA ➔ MS-A09WA -
MS-A12WA ➔ MS-A12WA -
1.Remote controller has been changed.
• Temperature indication function (_F/_C) has been added. (Refer to 11-8.)
• Timer indication has been changed. (AM/PM indication)
2.Conduit plate has been removed.
3.Conduit cover, terminal block cover and terminal block holder have been changed.
1
1
2
1TECHNICAL CHANGES
MS09TW➔ MS-A09WA
MS12TN ➔ MS-A12WA
1.Indoor fan motor has been changed.
2.Signal of remote controller has been changed. (It is not available for conventional models.)
Revision A :
• MS-A•WA-have been added.
Remote controller has been changed.
1
Remote controller
KM06C
KM07L
Temperature indication
_F
_F/ _C
MS-A09/12WA
MS-A09/12WA-
Models
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3
PART NAMES AND FUNCTIONS
2
MS-A09WA
MS-A12WA
Line flow fan
Air outlet
Vertical vane
Air inlet
Display section
Front panel
Panel
Heat exchanger
Horizontal vane
Operation section
(When the front panel is opened)
Remote controller
Remote control
receiving section
Catechin air filter
Air cleaning filter
(Anti-Allergy Enzyme
Filter, Blue bellows
type)
Emergency operation switch
Operation Indicator
lamp
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4
ACCESSORIES
1
2
3
4
5
6
7
8
Installation plate
Installation plate fixing screw 4 o25 mm
Remote controller holder
Fixing screw for 33.5 o1.6 mm (Black)
Battery (AAA) for remote controller
Wireless remote controller
Felt tape (Used for left or left-rear piping)
Conduit plate
1
8
1
2
2
1
1
1
1
5
1
2
2
1
1
-
MS-A09/12WA-MS-A09/12WA
MS-A09WA
MS-A12WA
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5
SPECIFICATION
3
Notes : Test conditions are based on ARI 210/240
❈1 : Rating conditions (cooling) —Indoor : 80˚FDB, 67˚FWB, Outdoor : 95˚FDB, (75˚FWB) Rated frequency : 60Hz
Operating Range
Cooling Maximum
Minimum
Indoor intake air temperature
95˚FDB, 71˚FWB
67˚FDB, 57˚FWB
Outdoor intake air temperature
115˚FDB
67˚FDB
Item Model MS-A12WA
Indoor unit model
External finish
Power supply
Max. fuse size (time delay)/ Disconnect switch
Min. circuit ampacity
Fan motor
Airflow Low—Med.—High
Moisture removal
Sound level Low-Med.-High
Cond. drain connection O.D.
Dimensions
Weight
Remote controller
Control voltage (by built-in transformer)
V, phase, Hz
A
A
F.L.A
CFM
pt./h
dB(A)
in.
in.
in.
in.
Ib.
MS-A12WA
1.2
0.95
406(363)-286(254)-222(198)
3.2
33-38-45
23
MS-A09WA
1.2
0.95
335(300)-261(233)-183(162)
2.7
26-32-40
23
MS-A09WA
COOL Dry (Wet)
W
D
H
-
White
115, 1, 60
15
5/8
30-11/16
8-1/4
11-3/4
Wireless type
115V AC
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6
4OUTLINES AND DIMENSIONS
MS-A12WA Unit : inch
MS-A09WA
11-3/4
424-9/16
30-11/16
8-1/4 3/16
2-1/8
3/4
6-1/4
2-5/16
Air in
Air out
Installation plate
6-1/8 6-1/8
7/8
1-3/4
13-3/16 12-5/8
1-5/8 8-7/16
10-1/8
1-11/16
8-7/16
1/8 11-5/16
2-3/4
2-3/16
2-3/16 2-3/16
8-7/8 8-7/8
9/1610-3/4
9-3/16
Wall hole [2-9/16
Indoor unit
Installation plate
7/16x13/16 Oblong hole
7/16x1 Oblong hole
7/8
hole
Conduit plate(MS-A•WA- is excluded.)
Insulation [1-1/8
Drain hose [5/8
(Connected part O.D)
Liquid line [1/4 19-11/16
Gas line [3/8 16-15/16
Insulation [1-3/8 O.D
[3/4 I.D
{
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7
WIRING DIAGRAM
5
REFRIGERANT SYSTEM DIAGRAM
6
MS-A09WA
MS-A12WA
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant flow in cooling
Refrigerant pipe [3/8 (MS-A09)
[1/2 (MS-A12)
(with heat insulator)
Refrigerant pipe [1/4
(with heat insulator)
Indoor coil
thermistor
RT12
Unit : inch
MS-A09WA
MS-A12WA
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8
7SERVICE FUNCTIONS
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.
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 8-7.)
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.)
No. 1 unit
No. 2 unit
No. 3 unit
No. 4 unit
1 unit operation
No modification
–
–
–
2 units operation
Same as at left
Solder J1
–
–
3 units operation
Same as at left
Same as at left
Solder J2
–
4 units operation
Same as at left
Same as at left
Same as at left
Solder both J1 and J2
Table 1
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.
How to modify the remote controller P.C. board
Remove batteries before modification.
The board has a print as shown below :
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.
NOTE : For modification, take out
the batteries and press the
OPERATE/STOP(ON/OFF)
button twice or 3 times at
first.
After finish modification,
put back the batteries then
press the RESET button.
J2
J1
MS-A09WA
MS-A12WA
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9
TROUBLESHOOTING
8
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 of 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
MS-A09WA MS-A12WA
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 appliance 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.
JR07
CN151 CN211CN112 CN1R1
BZ
7-3. AUTO RESTART FUNCTION
When the indoor unit is controlled with the remote controller, the operation mode, the 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.
Operation
1If the main power has been cut, the operation settings remain.
2After 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 release “AUTO RESTART FUNCTION”
1Turn off the main power for the unit.
2Solder the Jumper wire JR07 on the indoor electronic control P.C. board. (Refer to 8-7.)
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10
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 check 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 discoloration.
4) When troubleshooting, refer to 8-2., 8-3. and 8-4.
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.
RESET button
Insert the negative pole of the
batteries first. Check if the polarity
of the batteries are correct.
NOTE : 1. If RESET button is not pressed, the remote controller may not operate correctly.
2. 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.
2Press RESET button with tip end of ball point pen
or the like, and then use the remote controller.
1Remove the front lid and insert batteries.
Then reattach the front lid.
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