Mitsubishi Electric MSZ-HA25VA-E1 User manual

CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················2
3. SPECIFICATION·················································4
4. NOISE CRITERIA CURVES·······························5
5. OUTLINES AND DIMENSIONS ·························6
6. WIRING DIAGRAM ············································7
7. REFRIGERANT SYSTEM DIAGRAM················7
8. SERVICE FUNCTIONS ······································8
9. TROUBLESHOOTING······································10
10. DISASSEMBLY INSTRUCTIONS·····················22
11. PARTS LIST······················································25
12. RoHS PARTS LIST···········································28
13. OPTIONAL PARTS···········································31
MSZ-HA25VA -
MSZ-HA35VA - E1
E1
SPLIT-TYPE, HEAT PUMPAIR CONDITIONERS
NOTE:
This service manual describes technical data of the indoor 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 service manual
MUZ-HA·VA Series (OB453)
SERVICE MANUAL
Wireless type
Models
No. OB452
INDOOR UNIT
OB452--qxp 06.4.6 10:00 AM Page 1

2
1TECHNICAL CHANGES
MSZ-GA25VA - ➔MSZ-HA25VA -
MSZ-GA35VA - ➔MSZ-HA35VA - E1E1
E1E1
1. Indoor model has been changed.
PART NAMES AND FUNCTIONS
2
MSZ-HA25VA
MSZ-HA35VA
Air outlet
Vertical vane
Air inlet
Operation Indicator
lamp
Front panel
Air filter (Anti-mold)
Horizontal vane
Remote controller
Remote control
receiving section
Emergency operation switch (E.O. SW)
OB452--qxp 06.4.6 10:00 AM Page 2

3
ACCESSORIES
REMOTE CONTROLLER
1
2
3
4
5
6
Installation plate
Installation plate fixing screw 4 o25 mm
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)
1
5
2
2
1
1
MSZ-HA25VA
MSZ-HA35VA
Time set buttons
RESET button
Vane control button
Signal transmitting section
Operation display section
Temperature buttons
ON/OFF (operate/stop) button
Fan speed control button
Operation select button
Timer mode select button
ECONO COOL button
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4
3SPECIFICATION
INDOOR UNIT
Fuse
Horizontal vane motor
Varistor
Terminal block
(F11)
(MV)
(NR11)
(TB)
T3.15AL 250V
12V DC
ERZV14D471
3P
Specifications and rating conditions of main electric parts
NOTE : Test conditions are based on ISO 5151
Cooling : Indoor Dry-bulb temperature 27:Wet-bulb temperature 19:
Outdoor Dry-bulb temperature 35:Wet-bulb temperature 24:
Heating : Indoor Dry-bulb temperature 20:Wet-bulb temperature 15:
Outdoor Dry-bulb temperature 7:Wet-bulb temperature 6:
Refrigerant piping length (one way): 5m
✽1 Measured under rated operating frequency.
MSZ-HA25VA MSZ-HA35VA
Indoor model
Function
Power supply Single phase
230V,50Hz
10
0.22
23
0.22
RCOJ 40-ED
788O295O225
9
4
43
38/32/26
4
MP06B
Single phase
230V,50Hz
10
0.22
23
0.22
RCOJ 40-ED
788O295O225
9
4
43
38/32/26
4
MP06B
Cooling
630
558/420/318
1110
1000/800/650
Heating
546
468/390/306
980
870/750/630
Cooling
630
558/420/318
1110
1000/800/650
Heating
660
546/426/306
1150
980/810/630
Air flow(Super High)
Air flow(High/Med./Low)
Power outlet
Running current ✽1
Power input ✽1
Fan motor current ✽1
Model
Dimensions WOHOD
Weight
Air direction
Sound level(Super High)
Sound level(High/Med./Low)
Fan speed(Super High)
Fan speed(High/Med./Low)
Fan speed regulator
Remote controller model
K/h
K/h
A
A
W
A
mm
kg
dB(A)
dB(A)
rpm
rpm
Electrical data
Fan motor
Special remarks
Capacity
OB452--qxp 06.4.6 10:00 AM Page 4

5
NOISE CRITERIA CURVES
4
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
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
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
FUNCTION
43
43
SPL(dB(A)) LINE
Super High
FAN SPEED
HEATING
MSZ-HA25VA
INDOORUNIT WALL
MICROPHONE
0.8m
1m
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
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
COOLING
FUNCTION
43
43
SPL(dB(A)) LINE
Super High
FAN SPEED
HEATING
Test conditions,
Cooling : Dry-bulb temperature 27: Wet-bulb temperature 19:
Heating : Dry-bulb temperature 20: Wet-bulb temperature 15:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
MSZ-HA35VA
OB452--qxp 06.4.6 10:00 AM Page 5

6
5OUTLINES AND DIMENSIONS
MSZ-HA25VA Unit : mm
50
42
58
42
60753 128
295
58
42
2255
42
57
7459
41.5
214
235
253.5 18.5
320335 155 155
21540.5 254.5
5959 225 225
2
119
137
8
100
57
140
18
Piping
Insulation [35 O.D
Liquid line [6.35 - 0.5m (Flared connection [6.35)
Gas line [9.52 - 0.43m (Flared connection [9.52)
Drain hose Inslation[28 Connected part [16 O.D
Air in
Air out
Installation plate
Piping
Drain hose
11X26 Oblong hole
Installation plate
Indoor unit Wall hole [65
788
11X20 Oblong hole
MSZ-HA35VA
OB452--qxp 06.4.6 10:00 AM Page 6

7
WIRING DIAGRAM
6
REFRIGERANT SYSTEM DIAGRAM
7
MSZ-HA25VA
MSZ-HA35VA
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant flow in cooling
Refrigerant flow in heating
Refrigerant pipe [9.52
(with heat insulator)
Refrigerant pipe [6.35
(with heat insulator)
Indoor coil
thermistor
RT12
Unit : mm
MSZ-HA25VA
MSZ-HA35VA
OB452--qxp 06.4.6 10:00 AM Page 7

8
8SERVICE FUNCTIONS
8-2. 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.
8-1. 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 9-7.)
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 remodelling, take out
the batteries and press the
OPERATE/STOP(ON/OFF)
button twice or 3 times at
first.
After finish remodelling,
put back the batteries then
press the RESET button.
MSZ-HA25VA
MSZ-HA35VA
J2
J1
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9
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
Indoor electronic
control P.C. board
CN10A CN111CN151 CN112
8-3. 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 to JR07 on the indoor electronic control P.C. board. (Refer to 9-7.)
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10
9TROUBLESHOOTING
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 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 9-2., 9-3. and 9-4.
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.
Insert the minus 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 back lid and insert batteries.
Then reattach the back lid.
9-1. 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 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 P.C. board.
3) When removing the 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
MSZ-HA25VA MSZ-HA35VA
OB452--qxp 06.4.6 10:00 AM Page 10

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 (9-4.) 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.
9-2. Failure mode recall function
1. Flow chart of failure mode recall function for the indoor/outdoor unit
Operational procedure
Yes
(Blinks)
No
(OFF)
Yes
No
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:
W3.Blinking pattern when the outdoor unit is abnormal:
ON
OFF Beeps
Repeated cycle Repeated cycle
ON
OFF No beep Beeps
Repeated cycle
2.5-second OFF Blinking at 0.5-
second interval
2.5-second OFF 3-second ON Blinking at 0.5-
second interval
Beeps Repeated cycle
2.5-second OFF Blinking at 0.5-
second interval
No beep Beeps
Repeated cycle
2.5-second OFF 3-second ON Blinking at 0.5-
second interval
Repeated cycle
Beeps
Does the upper 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 are emitted at the same timing
as the blinking of the upper 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
Before blinking, does the upper lamp of
OPERATION INDICATOR lamp stay ON for 3
seconds?
Stays ON for 3 seconds (without beep):
The outdoor unit is abnormal.
The indoor unit is abnormal.
Check the blinking pattern, and confirm the abnormal point with the indoor unit
failure mode table(9-2.2.).
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 in operation display section of the
remote controller is displayed after 3 seconds.
Deleting the abnormal memorized 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.
Judgment of indoor/outdoor abnormality
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.
Confirm if outdoor unit is abnormal according to the detailed outdoor
unit failure mode recall function.
The outdoor unit is abnormal.
Check the blinking pattern, and confirm the abnormal point with the
outdoor unit failure mode table (Refer to outdoor unit service manual.)
Make sure to check at least two consecutive blinking cycles. W3
W1. Regardless of normal or abnormal,
a short beep is emitted once as 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 (9-4.).
12-time flash
2.5-second OFF Replace the indoor electronic control
P.C. board.
Indoor control system When 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 9-6.A"Check of indoor fan
motor".
Indoor fan motor When 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 indoor
coil thermistor (9-7.).
Indoor coil thermistor When the indoor coil thermistor short or open
circuit is detected every 8 seconds during
operation.
3-time flash
2.5-second OFF Refer to 9-6.D"How to check mis-wiring
and serial signal error".
Serial signal When the serial signal from outdoor unit is
not received for a maximum of 6 minutes.
1-time flash
every 0.5-second Refer to the characteristics of the room
temperature thermistor (9-7.).
Room temperature
thermistor
When the room temperature thermistor short
or open circuit is detected every 8
seconds during operation.
Not lighted —Normal —
Upper lamp of OPERATION
INDICATOR lamp
Correspondence
Abnormal point
(Failure mode) Condition
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13
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 only
in Test Run
operation.
w
Outdoor unit
doesn't
operate
even in
Test Run
operation.
w
Indoor unit
operates, when
EMERGENCY
OPERATION
switch is pressed.
Indoor unit
doesn't operate,
when
EMERGENCY
OPERATION
switch is pressed.
Check room
temperature
thermistor.
Refer to 9-7.
"Test point
diagram and
voltage".
Refer to
"How to check
inverter/
compressor".
Refer to 9-6.B
"Check of
remote controller
and indoor
electronic control
P.C. board".
1. Check indoor / outdoor
connecting wire.
(Check if the power
is supplied to the
indoor unit.)
2. Refer to 9-6.C
"Check of indoor
P.C. board and indoor
fan motor".
Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.
Refer to
"Check of
R.V. coil".
Upper lamp
Flash on and off
at 0.5-second
intervals
Cause:
Indoor/
Outdoor unit
• Mis-wiring
or trouble
of serial signal
Upper
lamp
2-time flash
Cause:
Indoor unit
• Trouble of
room temp-
erature/
indoor coil
thermistor
Upper lamp
3-time flash
Cause:
Indoor unit
• Trouble of
indoor fan
motor
Upper lamp
5-time flash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality
Upper lamp
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
Upper lamp
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Refer to 9-6.
D "How to
check of
mis-wiring
and serial
signal error
".
Check room
temperature
thermistor
and indoor
coil thermis-
tor.
Refer to 9-7.
"Test point
diagram and
voltage".
Refer to 9-6.
A"Check of
indoor fan
motor".
Refer to
"How to check
inverter/
compressor".
Refer to
"Check of
outdoor
thermistors".
Replace the
inverter P.C.
board or
the outdoor
electronic
control P.C.
board.
Upper lamp
14-time flash
Cause:
Outdoor unit
• Other
abnormality
Check
"Flow chart of
the detailed
outdoor unit
failure mode
recall function."
Upper lamp
4-time flash
Cause:
Indoor unit
• Trouble of
indoor unit
control
system
Replace the
indoor
electronic
control
P.C. board.
Refer to outdoor unit service manual.
Indoor unit operates.
Outdoor unit doesn't
operate normally.
If blinking of OPERATION
INDICATOR lamp cannot be
checked, it can be checked with
failure mode recall function.
w
"Test Run operation" means the
operation within 30 minutes after
EMERGENCY OPERATION switch
is pressed.
9-3. Instruction of troubleshooting
OB452--qxp 06.4.6 10:00 AM Page 13

14
No.
1
2
5
6
SymptomOperation indicator lamp Condition Correspondence
Upper lamp flashes.
0.5-second ON
0.5-second OFF
Mis-Wiring
or serial
signal
Outdoor
power
system
Outdoor
thermistors
Outdoor
control
system
Indoor coil
thermistor
When the serial signal from the outdoor unit is
not received for a maximum of 6 minutes.
When it consecutively occurs 3 times that the
compressor stops for overcurrent protection or
start-up failure protection within 1 minute after
start-up.
When the outdoor thermistors short or open
circuit during the compressor operation.
When it cannot properly read data in the
nonvolatile memory of the inverter P.C. board
or the outdoor electronic control P.C. board.
• Refer to "Check of outdoor
thermistor".
Refer to outdoor unit service
manual.
• Refer to "How to check of
inverter/compressor".
Refer to outdoor unit service
manual.
• Check the stop valve.
• Replace the inverter P.C.
board or the outdoor
electronic control P.C. board.
Refer to outdoor unit service
manual.
• Refer to 9-6.D"How to check
mis-wiring and serial signal
error".
3Indoor fan
motor
7
Abnormal
point
Room
temperatur
e thermistor
Upper lamp flashes.
2-time flash
2.5-second OFF
When the indoor coil or the room temperature
thermistor is short or open circuit.
• Refer to 9-7.the
characteristics of indoor coil
thermistor, and the room
temperature thermistor.
Upper lamp flashes.
3-time flash
2.5-second OFF
When the rotational frequency feedback
signal is not emitted during the indoor fan
operation.
• Refer to 9-6.A"Check of
indoor fan motor".
Indoor unit
and outdoor
unit do not
operate.
Upper lamp flashes.
5-time flash
2.5-second OFF
Upper lamp flashes.
6-time flash
2.5-second OFF
Other
abnormality
An abnormality other than above mentioned is
detected.
• Confirm the abnormality in
detail using the failure mode
recall function for outdoor
unit.
8
4
Upper lamp flashes.
4-time flash
2.5-second OFF
Indoor
control
system
When it cannot properly read data in the
nonvolatile memory of the indoor electronic
control P.C. board. • Replace the indoor electronic
control P.C. board.
Outdoor
control
system
When it cannot properly read data in the
nonvolatile memory of the inverter P.C. board
or the outdoor electronic control P.C. board.
• Check the blinking pattern of
the LED on the inverter P.C.
board or the outdoor
electronic
control P.C. board.
9Outdoor unit
does not
operate.
Upper lamp lights up
Upper lamp flashes.
7-time flash
2.5-second OFF
Upper lamp flashes.
14-time flash
2.5-second OFF
9-4. Troubleshooting check table
Not lighted
Blinking
OPERATION INDICATOR
Lighted
· Flashing of OPERATION INDICATOR lamp (upper 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
9-5. Trouble criterion of main parts
MSZ-HA25VA MSZ-HA35VA
Part name FigureCheck method and criterion
Indoor fan motor(MF)
Measure the resistance with a tester.
Refer to 9-7."Test point diagram and voltage",
"2.Indoor electronic control P.C. board", the chart of thermistor.
Room temperature
thermistor(RT11)
Indoor coil thermistor
(RT12)
Vane motor(MV) Normal
RED-BLK
Measure the resistance between the terminals with a tester.
(Part temperature 10°C ~ 30°C)
235 "~ 255 "
Color of the lead wire
Check 9-6. A.
BLK
BLK
RED
BLK BLK
ROTOR
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16
Check of indoor fan motor
A
When OPERATION INDICATOR lamp flashes 3-time.
Indoor fan does not operate.
Replace the indoor
power / terminal P.C. board
Replace the indoor
electronic control
P.C. board
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 P.C. board is normal.
Pay careful attention to the high voltage on
the fan motor connector CN211.
Yes
Yes
Yes
Yes
No
No No
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.
Replace the indoor power / terminal
P.C. board.
Replace the
indoor fan motor.
No Replace the indoor
electronic control
P.C. board.
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 following voltage on the indoor
P.C. board. w
<Indoor power P.C. board>
1.Measure the voltage between CN211 1(+) and 3(–).
2.Measure the voltage between CN211 5(+) and 3(–).
<Indoor electronic control P.C. board>
1.Measure the voltage between CN10A 6(+) and JPG(GND)(–).
No
(Changed)
Yes
(Unchanged)
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?
Is it unchanged holding
0V DC or 15V DC?
Is there 325V DC between
CN211 1(+) and 3(–) ?
Does the voltage between CN211
5 (+) and 3 (–) on the power
P.C. board rise to the range of 2V
to 6V DC within 12 seconds after
EMERGENCY OPERATION
switch is pressed?
Does the voltage between CN10A
6 (+) and JPG (GND)(–) on the
indoor electronic control P.C.
board fall to 2V or less within 12
seconds after EMERGENCY
OPERATION switch is pressed?
Yes (Unchanged) No (Changed)
Replace the indoor fan motor.
Measure the voltage CN10A 2(+) and
JPG (GND)(–) on the indoor electronic
control P.C board when the fan motor
is rotaring.
The indoor fan motor error has occurred, and the indoor fan doesn't operate.
JPG (GND)
CN10A
CN211
Indoor power P.C.board
Indoor electronic
control P.C. board
Fuse (F11)
Indoor terminal
P.C.board
Varistor
(NR11)
9-6. Troubleshooting flow
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17
Check of remote controller and indoor electronic control 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 9-1.4.)
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 1m?
Replace the indoor electronic
control P.C. board.
(including the receiver)
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 the remote
controller visible?
Remove the batteries, then set them back
and press RESET button. (Refer to 9-1.4.)
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 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.
w3. Please replace the fuse after removing
the indoor terminal P.C. board from the electrical box.
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 from indoor
power P.C. board and vane motor connector CN151
from the indoor electronic control P.C. board and turn
ON the power supply.
Measure the resistance of the vane motor coil.
Refer to 9-5.
Measure the resistance between CN211 3
and 4of the indoor fan motor connector. Short circuit:
Replace the indoor fan motor.
Short circuit:
Replace the 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 terminal P.C.
board visually.
Replace the varistor(NR11) and fuse(F11). w3
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?
Is the approx. 5VDC between 5V (+)
and JPG(GND) (–) of the indoor
electronic control P.C.board? Is there
approx. 9V to 13VDC between 12V (+)
and JPG (GND) (–) of the indoor
electronic control P.C. board.
Measure the resistance
between CN211 1(+) and 3(–)
of the indoor fan motor connector.
w1,w2
Replace the fuse (F11). w3
Replace the fuse (F11) and the indoor fan motor. w3
Is the resistance
approx. 4'?
Measure the resistance of cement
resistance R111 on the indoor power
P.C. board.
Replace the indoor
electronic control P.C. board.
Yes
Connect the connector or repair
disconnection.
Yes
No
Are connector CN10A on
the indoor electronic control
P.C. board or lead wires
disconnected? No
Replace the indoor power / terminal P.C. board.
Replace the indoor power / terminal P.C. board
and the indoor fan motor.
Yes
JPG (GND)
12VDC
5VDC
CN10A
CN211
Indoor power P.C.board
Indoor electronic
control P.C.board
Fuse (F11)
Indoor terminal
P.C.board
Varistor
(NR11) R111
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19
How to check mis-wiring and serial signal error
D
Is there rated voltage in
the power supply?
Is there any mis-wiring,
poor contact, or wire
disconnection of the
indoor/outdoor
connecting wire?
W1. Mis-wiring may damage indoor P.C. board during the
operation.
Be sure to confirm the wiring is correct before the
operation starts.
W3. Be sure to check this within 3 minutes after turning ON.
After 3 minutes, LED blinks 6 times. Even when
the inverter P.C.board or the outdoor electronic control
P.C.board is normal, LED blinks 6 times after 3 minutes.
(Except for outdoor unit of multi system type)
(Lighted or
not lighted)
No
Yes
No
Yes
Yes
No
Yes
No Yes
W2 Be careful to the residual
voltage of smoothing capacitor.
No
No
Yes
No
Yes
Yes
Turn OFF the power supply.
Turn ON the power supply.
Is there rated voltage between
outdoor terminal block S1 and
S2?
Does the upper lamp of OPERATION
INDICATOR lamp light up?
<Confirmation of the power to the indoor unit>
Press EMERGENCY OPERATION switch once.
Check the power
supply.
A
Turn OFF the power supply.
Check once more if the indoor/outdoor
connecting wire is not mis-wiring.
Short-circuit outdoor terminal block S2 and
S3.
W1
B
Turn ON the power supply.
Check the wiring.
Make them correct.
Turn OFF the power supply.
Remove the short-circuit between
outdoor terminal block S2 and S3.
Turn ON the power supply.
Is there amplitude of 10 to 20V DC
between indoor terminal block S2
and S3? <Confirmation of serial
signal>
Is there rated voltage between
indoor terminal block S1 and S2?
<Confirmation of power voltage>
No
No No Yes
Yes
Yes
Replace the inverter P.C. board or
the outdoor electronic control P.C.board.
W2
Is there any error of the
indoor/outdoor connecting wire,
such as the damage of the wire,
intermediate connection, poor
contact to the terminal block?
No
Replace the
indoor/outdoor
connecting wire.
Is serial signal
error indicated
6 minutes later?
Yes
No
· Turn OFF inverter-controlled lighting
equipment.
· Turn OFF the power supply and then
turn ON again.
· Press EMERGENCY OPERATION
switch.
B
· Reinstall
either the
unit or the
light each
other away.
· Attach a filter
on remote
control
receiving
section of
the indoor
unit.
A
Is serial signal error indicated 6 minutes later?
Is there 2V DC or less between CN10A3(+)
and JPG(GND)(–) on the indoor electronic
control P.C. board?
Is there 2V DC or less between
CN10A4(+) and JPG(GND)(–)
on the indoor electronic control
P.C. board?
Be sure to release the failure-mode recall function after checking.
Is there 2V DC or less between
CN10A4(+) and JPG(GND)(–)
on the indoor electronic control
P.C. board?
Does the LED on the inverter P.C. board
or the outdoor electronic control P.C. board
repeat "3.6-second-OFF and 0.8-second-ON
quick blinking"? W3
Replace the indoor power /
terminal P.C. board. Replace the indoor
electronic control P.C. board.
• When unit cannot operate neither by the remote controller nor by EMERGENCY OPERATION switch.
Indoor unit does not operate.
• When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second.
Outdoor unit does not operate.
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20
Electromagnetic noise enters into TV sets or radios
E
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 3m, or is the
distance between the
antennas and the outdoor
unit within 3m?
Is the distance between the
TV sets or radios and the
indoor unit within 1m, or is
the distance between the TV
sets or radios and the
outdoor unit within 3m?
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 is 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.
After checking the above, consult the service representative.
Is the unit earthed? Earth 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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