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
OB448A-1.qxp 07.5.14 4:20 PM Page 1

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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11
Outline of the function
This air conditioner can memorize the abnormal condition which has occurred once.
Even though LED indication listed on the troubleshooting check table (8-4.) disappears, the memorized failure details
can be recalled.
This mode is very useful when the unit needs to be repaired for the abnormality which doesn't recur.
8-2. Failure mode recall function
1. Flow chart of failure mode recall function for the indoor/outdoor unit
Operational procedure
Yes
(Blinks)
No
(OFF)
Releasing the failure mode recall function
Note1.Make sure to release the failure mode recall function once it's set up, otherwise the unit cannot operate properly.
2.If the abnormal condition is not deleted from the memory, the last abnormal condition is kept memorized.
W2. Blinking pattern when the indoor unit is abnormal:
ON
OFF Beeps
Repeated cycle Repeated cycle
2.5-second OFF Blinking at 0.5-
second interval
Beeps Repeated cycle
2.5-second OFF Blinking at 0.5-
second interval
Beeps
Does the left lamp of OPERATION INDICATOR
lamp on the indoor unit blink at the interval of 0.5
seconds?
Blinks: Either indoor or outdoor unit is abnormal.
Beep is emitted at the same timing
as the blinking of the left lamp of
OPERATION INDICATOR lamp. W2
The cause of abnormality cannot be found because the abnormality doesn't recur.
Setting up the failure mode recall function
The indoor unit is abnormal.
Check the blinking pattern, and confirm the abnormal point with the indoor unit
failure mode table(8-2.2.).
Make sure to check at least two consecutive blinking cycles. W2
Turn ON the power supply.
<Preparation of the remote controller>
1While pressing both OPERATION SELECT
button and TOO COOLbutton on the remote controller at the same time, press
RESET button.
2First, release RESET button.
And release the other two buttons after all LCD except the set temperature in
operation display section of the remote controller is displayed after 3 seconds.
Deleting the memorized abnormal condition
1After repairing the unit, recall the failure mode again according to
"Setting up the failure mode recall function" mentioned above.
2Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature is displayed)
with the remote controller headed towards the indoor unit.
3Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted.
4Release the failure mode recall function according to "Releasing the failure mode recall function"
mentioned above.
Repair the defective parts.
Release the failure mode recall function by the following procedures.
•Turn OFF the power supply and turn it ON again.
•Press RESET button of the remote controller.
Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature
is displayed) with the remote controller headed towards the indoor unit. W1
Indoor unit is normal.
But the outdoor unit might be abnormal because there are some
abnormalities that can't be recalled with this way.
W1. Regardless of normal or abnormal condition, a short
beep is emitted once the signal is received.
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12
2. Indoor unit failure mode table
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (8-4.).
12-time flash
2.5-second OFF Replace the indoor electronic control
P.C. board.
Indoor control system It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.
11-time flash
2.5-second OFF Refer to 8-6.A"Check of indoor fan
motor".
Indoor fan motor The rotational frequency feedback signal is
not emit during the 12-seconds the indoor fan
operation.
2-time flash
2.5-second OFF
Refer to the characteristics of the main
indoor coil thermistor, the sub indoor coil
thermistor (8-7.).
Indoor coil thermistor The indoor coil thermistor short or open
circuit is detected every 8 seconds during
operation.
1-time flash
every 0.5-second Refer to the characteristics of the room
temperature thermistor (8-7.).
Room temperature
thermistor
The room temperature thermistor short or
open circuit is detected every 8 seconds
during operation.
Not lighted –Normal –
Left lamp of OPERATION
INDICATOR lamp
Correspondence
Abnormal point
(Failure mode) Detection method
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13
8-3. Instruction of troubleshooting
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.w
Outdoor unit
operates
when the
EMERGENCY
OPERATION
switch is
pressed.
Outdoor unit
doesn't
operate
when the
EMERGENCY
OPERATION
switch is
pressed.
Indoor unit
operates when
EMERGENCY
OPERATION
switch is pressed.
Indoor unit
doesn't operate
when
EMERGENCY
OPERATION
switch is pressed.
Check the
room
temperature
thermistor.
Refer to 8-7.
"Test point
diagram and
voltage".
Refer to 8-6.B
"Check of
remote controller
and receiver
P.C. board".
Power lamp
2-time flash
Cause:
Indoor unit
•Trouble of the room
temperature/
indoor coil
thermistor
Power lamp
3-time flash
Cause:
Indoor unit
•Trouble of the
indoor fan
motor
Check the room
temperature
thermistor and the
indoor coil thermistor.
Refer to 8-7.
"Test point diagram
and voltage".
Refer to 8-6.A
"Check of
indoor fan
motor".
1. Check indoor /
outdoor
connecting wire.
2. Refer to 8-6.C
"Check of indoor
electronic control
P.C. board and
indoor fan motor."
•Check the
wiring diagram
of the outdoor
unit.
•Check
outdoor fuse.
Power lamp
4-time flash
Cause:
Indoor unit
•Trouble of the
indoor control
system
Replace the
indoor
electronic
control P.C.
board.
wIf flashing of
operation indicator lamp cannot
be checked, it can be checked
with failure mode recall function.
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14
No.
1
SymptomOperation indicator lamp
Detection method
Correspondence
Indoor coil
thermistor
2Indoor fan
motor
Abnormal
point
Room
tempera-
ture
thermistor
Left lamp flashes.
2-time flash
2.5-second OFF
The indoor coil or the room temperature
thermistor is short or open circuit. •Refer to 8-7.the
characteristics of indoor coil
thermistor, and the room
temperature thermistor.
Left lamp flashes.
3-time flash
2.5-second OFF
The rotational frequency feedback signal is
not emitted during the indoor fan operation. •Refer to 8-6.A"Check of
indoor fan motor".
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
3
Left lamp flashes.
4-time flash
2.5-second OFF
Indoor
control
system
It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.
Indoor unit
and outdoor
unit do not
operate.
•Replace the indoor electronic
control P.C. board.
8-4. Troubleshooting check table
Not lighted
Blinking
OPERATION INDICATOR
Lighted
·Flashing of OPERATION INDICATOR lamp (left-hand side lamp)
indicates abnormalities.
Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
When the indoor unit has started operation and the following 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
OPERATION INDICATOR lamp flashing.
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15
8-5. Trouble criterion of main parts
MS-A09WA MS-A12WA
Part name FigureCheck method and criterion
Indoor fan motor(MF)
Measure the resistance with a tester. (Part temperature 50˚F ~ 86˚F)
Refer to 8-7. "Test point diagram and voltage", the chart of thermistor.
Room temperature
thermistor(RT11)
Indoor coil thermistor
(RT12)
Horizontal vane
motor(MV) Normal
BRN-other one
Measure the resistance between the terminals with a tester.
(Part temperature 50°F ~ 86°F)
235 "~ 255 "
Color of the lead wire
Check 8-6. A.
RED
YLW
BRN
ORN GRN
ROTOR
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16
Check of indoor fan motor
A
When OPERATION INDICATOR lamp flashes 3-time.
Indoor fan does not operate.
wIf more than 12 seconds or more passes after EMERGENCY OPERATION
switch is pressed, the voltage mentioned above 2 goes 0V DC although
the indoor electric control P.C. board is normal.
Indoor electronic
control P.C. board
Pay careful attention to the high voltage on
the fan motor connector CN211.
Yes
No
No
No
(Changed)
Yes
(Unchanged)
Is there any foreign matter that
interferes the rotation of the
line flow fan?
Turn OFF the power supply.
Remove the foreign matter and
adjust the line flow fan.
Turn ON the power supply, wait 5 seconds or more, and then press
EMERGENCY OPERATION switch.
Measure the supply voltage as follows within 12 seconds
after EMERGENCY OPERATION switch is pressed.
If more than 12 seconds passes by, turn OFF the power supply and
turn ON it again, then measure the voltage. w
1.Measure the voltage between CN211 1(+) and 3(-).
2.Measure the voltage between CN211 5(+) and 3(-).
Is there 162V DC between
CN211 1(+) and 3(-), and does
the voltage between CN211 5(+)
and 3(-) rise to the range of 3 to 6V
DC within 12 seconds after
EMERGENCY OPERATION switch
is pressed?
Yes Replace the indoor fan motor.
CN211
Replace the indoor electronic control P.C. board.
The indoor fan motor error has occurred, and the indoor fan repeats "12-second ON and 30-second OFF" 3times, and then stops.
Measure the voltage between CN211
6(+) and 3(-) while the fan
motor is rotating.
Is it unchanged holding
0V DC or 15V DC?
Replace the indoor fan motor.
Replace the indoor electronic control P.C. board.
The indoor fan motor error has occurred, and the indoor fan doesn't operate.
8-6. Troubleshooting flow
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17
Check of remote controller and receiver P.C. board
B
Indoor unit operates by pressing EMERGENCY OPERATION switch, but does not operate with the remote controller.
wCheck if the remote controller is exclusive for this air conditioner.
Yes
Replace the batteries. (Refer to 8-1.4.)
Turn ON a radio to AM and press switch
ON the remote controller.
Is noise heard from radio?
Are there any fluorescent lights of
inverter or rapid-start type within
the range of 3.28ft.?
Replace the indoor electronic
control P.C. board.
Replace the remote controller.
● Reinstall the unit away from lights.
● Attach a filter on receiving part.
Switch ON the remote controller.
Is LCD display on the remote con-
troller visible?
Remove the batteries, then set them back
and press RESET button. (Refer to 8-1.4.)
Check if the unit operates with the remote
controller.
Yes
Does the unit operate with the
remote controller?
Yes
OK
No
(not clear)
Yes
No
No
No
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18
The unit does not operate with the remote controller.
Also, OPERATION INDICATOR lamp does not light up by pressing EMERGENCY OPERATION switch.
Check of indoor electronic control P.C. board and indoor fan motor
C
Yes
No
w1. The fan motor connector's 1lead wire is red, whereas 3is black.
w2. Connect "+" of the tester to fan motor connector's 1lead
wire, and "-" to 3lead wire, otherwise the resistance cannot be
measured properly.
Yes
No
Does the unit operate with the remote controller?
Does OPERATION INDICATOR lamp light up by
pressing EMERGENCY
OPERATION switch?
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.
Measure the resistance of the horizontal vane
motor coil.
Refer to 8-5.
Measure the resistance between CN211 3
and 4of the indoor fan motor connector. Short/open circuit:
Replace the indoor fan motor.
Short/open circuit:
Replace the horizontal vane motor and the indoor
electronic control P.C. board.
Turn OFF the power supply.
Check both “parts side”and “pattern
side”of the indoor electronic control P.C.
board visually.
Replace the indoor electronic control P.C. board.
Are the varistor(NR11) burnt
and the fuse(F11) blown?
Be sure to check both the fuse
and the varistor in any case.
No
Yes
No
Is the fuse(F11) blown only?
Yes
No
Is the resistance 1M"
or more?
Measure the resistance between
1(+) and 3(-) of the indoor fan
motor connector (to CN211 on the
indoor electronic control P.C. board) .
w1,w2
Replace indoor electronic control P.C. board.
Is the resistance
approx. 2"?
Measure the resistance of cement
resistor R111 on the indoor electronic
control P.C. board.
Replace the indoor electronic control P.C. board.
Replace the indoor electronic control P.C. board
and the indoor fan motor.
Replace indoor electronic control P.C. board
and the indoor fan motor.
Yes
CN211
Fuse(F11)
Varistor(NR11)
Indoor electronic
control P.C.Board
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19
Electromagnetic noise enters into TV sets or radios
D
Replace or repair the antenna.
Replace or repair the coaxial cable.
No
No
No
Yes
Yes
No
No
Yes
Yes
Yes
Is the distance between the
antennas and the indoor
unit within 9.91ft., or is the
distance between the
antennas and the outdoor
unit within 9.91ft.?
Is the distance between the
TV sets or radios and the
indoor unit within 3.28ft., or is
the distance between the TV
sets or radios and the
outdoor unit within 9.91ft.?
Are the antennas damaged?
Is the coaxial cable damaged?
Is there any poor contact in
the antenna wiring?
Is the indoor/outdoor
connecting wire of the air
conditioner and the wiring of
the antennas close?
Even if all of the above conditions are fulfilled, the electromagnetic noise may enter, depending on
the electric field strength or the installation condition (combination of specific conditions such as
antennas or wiring).
Check the followings before asking for service.
1.Devices affected by the electromagnetic noise
TV sets, radios (FM/AM broadcast, shortwave)
2.Channel, frequency, broadcast station affected by the electromagnetic noise
3.Channel, frequency, broadcast station unaffected by the electromagnetic noise
4.Layout of ;
indoor/outdoor unit of the air conditioner, indoor/outdoor wiring, grounding wire, antennas, wiring
from antennas, receiver
5.Electric field intensity of the broadcast station affected by the electromagnetic noise
6.Presence or absence of amplifier such as booster
7.Operation condition of air conditioner when the electromagnetic noise enters in
1)Turn OFF the power supply once, and then turn ON the power supply. In this situation, check for
the electromagnetic noise.
2)Within 3 minutes after turning ON the power supply, press OPERATE/STOP (ON/OFF) button
on the remote controller for power ON, and check for the electromagnetic noise.
3)After a short time (3 minutes later after turning ON), the outdoor unit starts running. During
operation, check for the electromagnetic noise.
4)Press OPERATE/STOP (ON/OFF) button on the remote controller for power OFF, when the
outdoor unit stops but the indoor/outdoor communication still runs on. In this situation, check for
the electromagnetic noise.
Is the unit grounded? Ground the unit.
Extend the distance between
the antennas and the indoor
unit, and/or the antennas and
the outdoor unit.
Extend the distance between
the TV sets and/or radios and
the indoor unit, or the TV sets
or radios and the outdoor unit.
Extend the distance between
the indoor/outdoor connecting
wire of the air conditioner and
the wiring of the antennas.
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20
Indoor coil thermistor [RT12]
Room temperature thermistor (RT11)
Temperature (-F)
32 50 68 86
104 122 140
Resistance (k")
MS-A09WA MS-A12WA
Indoor electronic control P.C. board
Release of Auto restart
function
Solder the Jumper wire
to JR07
(Refer to 7-3.)
115V AC Fuse(F11)
250V 3.15A
Indoor coil thermistor
RT12 23
(CN112)
Horizontal vane
motor(CN151)
8-7. Test point diagram and voltage
SW P.C. board
Power monitor
receiver P.C.
board 12V DC
5V DC
Power supply input
Indoor fan motor
(CN211)
}
Varistor (NR11)
Room temperature
thermistor(RT11)
}
Timer short mode
point JPG, JPS
(Refer to 7-1.)
5(+)3-6V DC
415 V DC
3(-) Fiducial terminal of
cathode side on measur-
ing high-voltage DC
1325V DC
6(+)0V DC or 15V DC
Emergency
operation switch
Cement
resistor
(R111)
OB448A-1.qxp 07.5.14 4:21 PM Page 20