Mitsubishi Electric MSZ-FA25VA User manual

CONTENTS
1. TECHNICAL CHANGES ····································2
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. SERVICE FUNCTIONS ······································9
9. TROUBLESHOOTING······································11
10. DISASSEMBLY INSTRUCTIONS·····················31
11. PARTS LIST······················································35
12. RoHS PARTS LIST···········································39
13. OPTIONAL PARTS···········································42
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.
SERVICE MANUAL
Wireless type
Models
MSZ-FA25VA -
MSZ-FA25VA -
MSZ-FA25VA -
MSZ-FA35VA -
MSZ-FA35VA -
MSZ-FA35VA - E3
E2
E1
E3
E2
E1
No. OB371
REVISED EDITION-B
INDOOR UNIT
Outdoor unit service manual
MUZ-FA·VA(H) Series (OB372)
MXZ-A·VA Series (OB377)
MXZ-8A140VA1(OC316)
Revision:B
●model has been added.
● 9-2. Failure mode recall function has been
changed.
●RoHS PARTS LIST has been added.
E3
Please void OB371 REVISED EDITION-A.
OB371B--1qxp 06.5.10 2:00 PM Page 1

• model has been added.
•9-2. Failure mode recall function has been changed.
•RoHS PARTS LIST has been added.
E3
2
1TECHNICAL CHANGES
MSZ-A09YV - ➔MSZ-FA25VA -
MSZ-A12YV - ➔MSZ-FA35VA - E1E1
E1E1
12. PLASMA DEODORIZING/AIR PURIFYING filter units have been added.
13. i-see Sensor has been added.
(i-see control operation and AREA setting have been added.)
14. Air cleaning filer has been removed.
15. Signal of remote controller has been changed. (It is not available for the conventional models.)
16. Symbol on terminal block has been changed (to S1/S2/S3).
NOTE: Do not remove the vane motor from the motor unit.
Do not disassemble the horizontal vane motor unit.
11. Front panel driving motor unit which opens and closes the front panel has been added.
Front panel opening/closing
output gear
NOTE: Do not disassemble the front panel driving motor unit.
Generalized stepping motor
10. The vertical vane motor unit has been added.
An external gear is added to the generalized stepping motor.
The unit is structured so that the driving torque and stopping torque would increase.
Generalized stepping motor
NOTE: Do not remove the vane motor from the motor unit.
Do not disassemble the vertical vane motor unit.
1. Indication of capacity has been changed.(BTU base ➔kW base)
2. Controller method between indoor and outdoor has been changed.
3. Power supply method has been changed (change to supply from outdoor unit).
4. Power supply cord has been removed.
5. Indoor electronic control P.C. board has been changed.
6. Position of terminal block has been changed.
7. Indoor fan motor has been changed. ( AC ➔DC)
8. Indoor heat exchanger has been changed.
9. The horizontal vane motor unit has been changed.
An external gear is added to the generalized stepping motor.
The unit is structured so that the driving torque and stopping torque would increase.
• model has been added.
Color of BOX and CORNER BOX has been changed to white.
E2
Revision:A
Revision:B
OB371B--1qxp 06.5.10 2:00 PM Page 2

3
PART NAMES AND FUNCTIONS
2
MSZ-FA25VA
MSZ-FA35VA
Line flow fan
Air outlet
Vertical vane
Air inlet
Display section
Front panel
PLASMA DEODORIZING filter
Panel
Heat exchanger
Horizontal vane
Operation section
(When the front panel is opened)
Remote controller
POWER lamp
Remote control
receiving section
PLASMA AIR PURIFYING filter
Anti-mold air filter Fan guard
i-see Sensor
PLASMA/WASH lamp
AREA lamp
Emergency operation
switch
WASH reset switch
Auto front panel
When the unit starts operating, the
front panel opens automatically to
draw in air. When the unit stops
operating, the front panel closes
automatically.
AREA lamp indicate AREA setting
In AREA setting, the horizontal air flow
direction changes automatically according
to the detection of i-see Sensor which detects
the floor/ wall temperature to air-condition
the room evenly.
i-see control operation
i-see sensor constantly measure
floor/wall temperature to automatically
adjust to the set temperature by
estimating the temperature
actually perceived by a
person inside the room
("sensible temperature").
<Open> <Closed>
Auto front panel
MSZ-FA25VA- ➔ MSZ-FA25VA-
MSZ-FA35VA- ➔ MSZ-FA35VA-
1. Color of BOX and CORNER BOX has been changed to white.
E2E1
E2E1
1. The operation of thermo-off-unit has been changed. (When 2 or more indoor units are connected with a multi type outdoor
unit, and operated in heat mode.)
< , > Indoor fan operates with very Low speed or stops.
< > Indoor fan operates intermittently with very Low speed or stops.
E3
E2E1
MSZ-FA25VA- ➔ MSZ-FA25VA-
MSZ-FA35VA- ➔ MSZ-FA35VA- E3E2
E3E2
OB371B--1qxp 06.5.10 2:01 PM Page 3

4
ACCESSORIES
1
2
3
4
5
6
7
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)
1
5
1
2
2
1
1
ON-TIMER button
CLOCK SET button
TIME SET buttons
FORWARD button
BACKWARD button
VANE CONTROL button
(Horizontal vane button)
OFF-TIMER button
i-see button
(This diagram shows an overall view.)
Open the front lid.
PLASMA button
AREA button
RESET button
WIDE VANE button
(Vertical vane button)
Signal transmitting section
Operation display section
Temperature buttons
OPERATE/STOP
(ON/OFF) button
FAN SPEED CONTROL button
OPERATION SELECT button
ECONO COOL button
Indication of
remote controller
model is on back
MSZ-FA25VA
MSZ-FA35VA
REMOTE CONTROLLER
OB371B--1qxp 06.5.10 2:01 PM Page 4

5
SPECIFICATION
3
T3.15AL250V
NSEJ001DA1 12V DC 100"(at 25˚C)
MP20Z 12V DC 300"(at 25˚C)
MSBPC20M16 12V DC 250"(at 25˚C)
MSBPC20M11 12V DC 300"(at 25˚C)
ERZV14D471
A2TPMI334F0V50HSOBA060P5L1J4S 5V DC
3P
Item
Fuse
Front panel driving motor
i-see Sensor motor
Horizontal vane motor
Vertical vane motor
Varistor
i-see Sensor
Terminal block
(F11)
(MP)
(MT)
(MV1)
(MV2)
(NR11)
(RR)
(TB)
Specifications and rating conditions of main electric parts
MSZ-FA25VA MSZ-FA35VA
Indoor model
Function
Power supply Single phase
230V,50Hz
10
0.25
33
57
0.25
RC0J40-EB or RC0J30-CC
780O298O198
10
4
42
36/29/21
4
KM05A
Cooling
594
474/354/252
1,220
1,010/800/610
Heating
612
498/384/264
1,250
1,050/850/640
Single phase
230V,50Hz
10
0.25
33
57
0.25
RC0J40-EB or RC0J30-CC
780O298O198
10
4
42
36/29/22
4
KM05A
Cooling
594
474/354/258
1,220
1,010/800/630
Heating
612
498/384/276
1,250
1,050/850/660
Air flow(Super High)
Air flow(High/Med./Low)
Power outlet
Running current ✽1
Power input ✽1
Power factor ✽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
MSZ-FA25VA MSZ-FA35VA
Indoor model
Function Cooling
546
450/348/252
1,130
960/790/610
Heating
540
420/372/264
1,120
910/830/640
Cooling
516/390/258
1,080/860/630
Heating
522/402/276
1,090/880/660
Air flow(Super High)
Air flow(High/Med./Low)
Sound level(Super High)
Sound level(High/Med./Low)
Fan speed(Super High)
Fan speed(High/Med./Low)
K/h
K/h
dB(A)
dB(A)
rpm
rpm
Special remarks
Capacity
42
36/29/21
642
42
36/29/22
1,300
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.
When outdoor unit is MXZ-8A140VA1 type.
OB371B--1qxp 06.5.10 2:01 PM Page 5

6
4NOISE CRITERIA CURVES
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
42
42
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:
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
Test conditions,
Cooling : Dry-bulb temperature 27: Wet-bulb temperature 19:
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
COOLING
FUNCTION
42
42
SPL(dB(A)) LINE
Super High
FAN SPEED
HEATING
Heating : Dry-bulb temperature 20: Wet-bulb temperature 15:
MSZ-FA25VA MSZ-FA35VA
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7
OUTLINES AND DIMENSIONS
5
MSZ-FA25VA Unit : mm
780
155 155
335 320
41.5 215
42.5 214
3 287.5
7055
5555 225 225
298
90
106
or more7
100
198 5
53.5 102624.5
19
159
58
234 14273.5
Air in
Air out
Wall hole [65
Indoor unit
Installation plate
Installation plate
11o20 Oblong hole
11o26 Oblong hole
10 or more
75 or more
55 or morew
75 or more
wIn case of left, left back, or left under piping (using spacer), 113 or more
Insulation [28
Drain hose [16
(Connected part O.D)
Liquid line [6.35 - 0.5m
Gas line [9.52 - 0.43m
Insulation [35 O.D
[19 I.D
{
Required space (Indoor unit)
Wireless remote controller
MSZ-FA35VA
OB371B--1qxp 06.5.10 2:01 PM Page 7

8
6WIRING DIAGRAM
REFRIGERANT SYSTEM DIAGRAM
7
MSZ-FA25VA
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT13(sub)
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(main)
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT13(sub)
Flared connection
Refrigerant pipe [9.52
(with heat insulator)
Refrigerant pipe [6.35
(with heat insulator)
Indoor coil
thermistor
RT12(main)
Unit : mm
SYMBOL
DB111
F11
MF
MP
MT
MV1
SYMBOL
MV2
NR11
PLASMA_A
PLASMA_D
RR
RT11
SYMBOL
RT12
RT13
T111
TB
NAME
DIODE STACK
FUSE (T3.15AL250V)
INDOOR FAN MOTOR
FRONT PANEL DRIVING MOTOR
i-see Sensor MOTOR
VANE MOTOR (HORIZONTAL)
NAME
VANE MOTOR (VERTICAL)
VARISTOR
PLASMAAIR PURIFYING FILTER UNIT
PLASMA DEODORIZING FILTER UNIT
i-see Sensor
ROOM TEMPERATURE THERMISTOR
NAME
INDOOR COIL THERMISTOR (MAIN)
INDOOR COIL THERMISTOR (SUB)
TRANSFORMER
TERMINAL BLOCK
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
MSZ-FA25VA
MSZ-FA35VA
MSZ-FA35VA
1
2
3
4
S2
8
230V~
BLU
INDOOR ELECTRONIC
CONTROL P.C. BOARD
33
PLASMA_DPLASMA_A
SAFETY DEVICE
(PLASMA UNIT)
MP
RR
54
MT
SW P.C.
BOARD
POWER MONITOR
RECEIVER P.C. BOARD
INTERLOCK
SWITCH(FAN)
55
MV2
MV1
TO OUTDOOR
UNIT
CONNECTING
BLK
RED
S3
TB TAB3
DB111
NR11
F11
5
6
4
2
5
CN
1U1
2
CN
1T2
CN
1T1
CN
110
3
LD
105(T)
LD
101(A)
12-24V
RT13
2
1R1
CN
GRN
LD104
CN201
2
1
151
CN
T111
RED
WHT
111
CN
CN
112
CN211 BLU
YLW
BLK
MF
RT11
RT12
1
3
5
S1
OB371B--1qxp 06.5.10 2:01 PM Page 8

9
SERVICE FUNCTIONS
8
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.)
MSZ-FA25VA
MSZ-FA35VA
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 only accepts 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.
J2
J1
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.)
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.
OB371B--1qxp 06.5.10 2:01 PM Page 9

10
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 works 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.
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.)
JR07
CN151 CN211CN112 CN1R1
CN212
CN1T1CN1T2
CN130
IC156
8-4. Remote controller
Be sure to set the slide switch inside the remote controller to an appropriate position in accordance with the
installed position of the indoor unit. If the switch is not set correctly, the air conditioner may not function properly.
Area Left Center Right
Position of
the slide
switch
Display on
the remote
controller
Where is the indoor unit installed in your room?
Installed at left , if the
distance is not more
than 50 cm.
NOTE:If the indoor unit is installed more than 50 cm away from the side walls, cabinets or other nearby objects, set the slide
switch to the “center” position.
Installed at right, if the
distance is not more
than 50 cm.
Is the indoor unit in-
stalledatright, left or
center?
(Left) (Center) (Right)
Side swich
OB371B--1qxp 06.5.10 2:01 PM Page 10

21 Stopper
Lock.
Left
Insert this end first.
11
TROUBLESHOOTING
9
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 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.
RESET button
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 main 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
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.
MSZ-FA25VA
MSZ-FA35VA
If horizontal vane is not installed correctly, All of the operation indicator lamps will blink.
In this case, install the horizontal vane correctly by following the procedures 1to 2.
NOTE: Before installation of the horizontal vane, turn OFF the power supply.
5. How to install the horizontal vane
In procedure 22lock the
stoppers until they click
into place.
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12
If PLASMA/WASH lamp on the indoor unit blinks, clean the filters as soon as possible. The lamp will start blinking when
accumulated operating time exceeds 330 hours.
<Remove>
(1) Switch the indoor unit OFF with the remote controller and
disconnect the power supply plug and/ or turn OFF the
breaker.
NOTE: Otherwise, you may get injured since PLASMA
DEODORIZING/AIR PURIFYING filter units are
charged with high voltage.
(2) Hold the knobs on both sides of the front panel and lift the
panel up until its level.
(3) Remove the anti-mold air filter.(See Figure 1.)
(4) Remove PLASMA DEODORIZING/AIR PURIFYING filter
units. (See Figure 2.)
Figure 1.
Figure 2.
(1) Insert the top of PLASMA DEODORIZING/AIR PURIFYING filter
units into the aperture in the plasma element holder.
(See Figure 3.)
(2) Push in PLASMA DEODORIZING/AIR PURIFYING filter units
until they click into place.
•The front panel does not close if PLASMA DEODORIZING/AIR
PURIFYING filter units are not installed properly.
(3) Install the anti-mold air filter.
(4) Connect the power supply plug and/ or turn ON the breaker.
(5) Press WASH reset switch. A short “beep” is heard and the blinks
of PLASMA/WASH lamp will be cancelled. Make sure PLASMA/
WASH lamp is not blinking at the start of operation next time.
(See Figure 4.)
(6) Hold both sides of the front panel and close the front panel.
(7) Press the 3 positions on the front panel as indicated by the
arrows.(See Figure 5.)
WASH
reset
E.O.
SW
<Install>
Install PLASMA DEODORIZING/AIR PURIFYING filter units by following the removal procedure in reverse.
Figure 3.
Figure 4.
Figure 5.
Plasma
element
holder
6. How to remove and install PLASMA DEODORIZING / AIR PURIFYING filter units
NOTE:
Install PLASMA DEODORIZING/AIR PURIFYING filter units only
when they are completely dry. If the filter unit remains wet,
PLASMA/WASH lamp may blink and the plasma function may be
disabled.(When PLASMA DEODORIZING/AIR PURIFYING filter
units are cleaned.)
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13
INFORMATION FOR MULTI SYSTEM AIR CONDITIONER
OUTDOOR UNIT : MXZ series
Multi system air conditioner can connect two or more indoor units with one outdoor unit.
•Unit won’t operate in case the total capacity of indoor units exceeds the capacity of outdoor units. Do not
connect indoor units beyond the outdoor unit capacity.
Operation indicator lamp flashes as shown in the figure below.
•When you try to operate two or more indoor units with one outdoor unit simultaneously, one for the cooling and
the other for heating, the operation mode of the indoor unit that operates earlier is selected. The other indoor
units which start the operation later cannot operate, indicating as shown in the figure below. In this case,
please set all the indoor units to the same operation mode.
•When indoor units start the operation while the defrosting of outdoor unit is being done, it takes a few minutes
(max. 10 minutes) to blow out the warm air.
•In the heating operation, though indoor unit that does not operate may get warm or the sound of refrigerant
flowing may be heard, they are not malfunction. The reason is that the refrigerant continuously flows into it.
Lighted
Blinking
Not lighted
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14
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 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
W1. Regardless of normal or abnormal, a short
beep is emitted once as the signal is received.
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 POWER 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 POWER 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 POWER
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 (9-2.4.).
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 COOL button 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 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
The plasma or outdoor unit might be abnormal because there are some
abnormalities that can't be recalled with this way.
Confirm if plasma unit or outdoor unit is abnormal according to the flow
chart of the plasma unit or 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
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15
2. Flow chart of PLASMA DEODORIZING/PLASMA AIR PURIFYING power failure mode recall function
Operational procedure
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 plasma unit is abnormal:
Yes
(Blinks)
No
(OFF)
W1. Regardless of normal or abnormal, a short
beep is emitted as the signal is received.
Does POWER lamp on the indoor
unit blink at the interval of 0.5 seconds?
Blinks: The plasma unit is abnormal.
Beep are emitted at the same timing as the
blinking of POWER lamp. W2
Deleting the abnormal memorized condition
Repair the defective parts.
With the remote controller headed towards the indoor unit, press TOO COOL or TOO
WARM button to adjust the set temperature to 23:. W1
The plasma unit is normal.
Releasing the failure mode recall function
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.
The plasma unit is abnormal.
Check the blinking pattern, and refer to confirm the
abnormal point with the PLASMA DEODORIZING/PLASMA AIR
PURIFYING power failure mode table (9-2.5.).
Make sure to check at least two consecutive blinking cycles. W2
Release the failure mode recall function according to the left
mentioned procedure.
Confirm that the remote controller is in the failure mode recall
function.
The plasma unit might be abnormal.
Confirm if plasma unit is abnormal according to the following procedures.
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
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.
3. PLASMA DEODORIZING/PLASMA AIR PURIFYING power operation check
NOTE: Perform the above mentioned check with the front panel closed (Refer to 9-1.6 Figure5). The SAFETY DEVICE
(PLASMA UNIT) works by opening front panel and the plasma power is cut.
ActionPLASMA/WASH lamp
Continuously blinking
2-time flash
Follow "Check of PLASMA DEODORIZING power" or "Check of PLASMA AIR PURIFYING power"
to identify the error.(Refer to 9-6.For G.)
PLASMA DEODORIZING power and/or PLASMA AIR PURIFYING power control circuit on the indoor
electronic control P.C. board is out of order.(Refer to 9-6.For G.)
PLASMA DEODORIZING/PLASMA AIR PURIFYING power goes ON when PLASMA button on the remote contoller is pressed
with any set temperature displayed during failure mode recall function.
PLASMA button is pressed, the power of plasma is changed in sequence:
PLASMA DEODORIZING power goes ON ➔PLASMA AIR PURIFYING power goes ON ➔Cancel
Check the operation display section of the remote controller to confirm that PLASMA DEODORIZING power or PLASMA AIR
PURIFYING power is activated.
While PLASMA/WASH lamp stays OFF, it means normal.
Flashing PLASMA/WASH lamp means abnormal, the plasma power is not conducted.
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16
4. Indoor unit failure mode table
5. PLASMA DEODORIZING/PLASMA AIR PURIFYING power failure mode table
5-time flash
When the voltage between CN1 3(+)
and 2(GND) on the PLASMA POWER P.C.
board (in the PLASMA DEODORIZING or
PLASMA AIR PURIFYING unit) rises above
the normal voltage value (3V).
4-time flash
PLASMA DEODORIZING/
PLASMA AIR PURIFYING
power
When the voltage between CN1 3(+)
and 2(GND) on the PLASMA POWER P.C.
board (in the PLASMA DEODORIZING or
PLASMA AIR PURIFYING unit) falls
significantly. (0.4V / 0.5ms)
3-time flash
Refer to 9-6.F"Check of PLASMA
DEODORIZING power" or 9-6.G"Check
of PLASMA AIR PURIFYING power".
Abnormal electric
discharge error 1
When the voltage between CN1 3(+)
and 2(GND) on the PLASMA POWER P.C.
board (in the PLASMA DEODORIZING or
PLASMA AIR PURIFYING unit) falls by 0.9V
below the normal voltage value (3V).
2-time flash Spark discharge
1-time flash PLASMA DEODORIZING/
PLASMA AIR PURIFYING
power control
When the voltage between CN1 3(+)
and 2(GND) on the PLASMA POWER P.C.
board (in the PLASMA DEODORIZING or
PLASMA AIR PURIFYING unit) falls below
1.6V(spark discharge judgment voltage).
When PLASMA DEODORIZING and/or
PLASMA AIR PURIFYING power cannot be
turned OFF even if the PLASMA operation is
turned OFF with the remote controller.
POWER lamp Correspondence
Abnormal point
(Failure mode) Condition
Abnormal electric
discharge error 2
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (9-4.).
NOTE1 :Blinking patterns of this mode differ from the ones of Troubleshooting check table (9-4.).
NOTE2 :As soon as an abnormality is detected, PLASMA DEODORIZING power and/or PLASMAAIR PURIFYING
power goes OFF, therefore measuring instrument which records the voltage wave is required in order to
perform the above mentioned voltage measurement.
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 emitted during the 12-seconds
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 (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 the 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 –
POWER lamp Correspondence
Abnormal point
(Failure mode) Condition
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17
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 receiver
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
electronic control
P.C. board and indoor
fan motor".
PLASMA/WASH lamp
2-time flash
cause:
Indoor unit
• Trouble of PLASMA
DEODORIZNG power
control and/or PLASMA
AIR PURIFYING power
control
Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.
Refer to
"Check of
R.V. coil".
POWER lamp
Flash on and off
at 0.5-second
intervals
Cause:
Indoor/
Outdoor unit
• Mis-wiring
or trouble
of serial signal
POWER lamp
2-time flash
Cause:
Indoor unit
• Trouble of
room temp-
erature/
indoor coil
thermistor
POWER lamp
3-time flash
Cause:
Indoor unit
• Trouble of
indoor fan
motor
POWER lamp
5-time flash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality
POWER lamp
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
POWER 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
.
All lamps
Flash on and off
at 0.5-second
intervals
Cause:
Indoor unit
• The horizontal
vane is not
installed
correctly.
Refer to 9-6.
E "Check of
installation of
the horizontal
vane".
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.
POWER lamp
14-time flash
Cause:
Outdoor unit
• Other
abnormality
Check
"Flow chart of
the detailed
outdoor unit
failure mode
recall function."
Left lamp
of AREA 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.
Refer to 9-6.F"Check of
PLASMA DEODORIZING
power" or 9-6.G"Check of
PLASMA AIR PURIFYING
power".
9-3. Instruction of troubleshooting
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18
No.
1
3
5
6
SymptomOperation indicator lamp Condition
Correspondence
POWER 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 form 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".
4Indoor fan
motor
7
Abnormal
point
Outdoor unit
does not
operate.
Room
tempera-
ture
thermistor
POWER 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.
POWER lamp flashes.
3-time flash
2.5-second OFF
When the rotational frequency feedback
signal is not emit during the indoor fan
operation. • Refer to 9-6.A"Check of
indoor fan motor".
Indoor unit
and outdoor
unit do not
operate.
POWER lamp flashes.
5-time flash
2.5-second OFF
POWER lamp flashes.
6-time flash
2.5-second OFF
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
Other
abnonmality
An abnormality other than above mentioned is
detected. • Confirm the abnormality in
detail using the failure mode
recall function for outdoor unit.
Indoor unit
and outdoor
unit do not
operate.
Indoor unit
and outdoor
unit do not
operate.
8
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.
2Outdoor unit
does not
operate.
POWER lamp flashes.
7-time flash
2.5-second OFF
POWER lamp flashes.
14-time flash
2.5-second OFF
POWER lamp lights up
9-4. Troubleshooting check table
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.
Lighted
Blinking
Not lighted
· Flashing of POWER lamp indicates abnormalities.
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19
Lighted
Blinking
Not lighted
Lighted
Blinking
Not lighted
Lighted
Blinking
Not lighted
· Flashing of AREA lamp(left-hand side lamp) indicates abnormality.
No.
1
SymptomOperation indicator lamp Condition
Correspondence
Abnormal
point
Left lamp of AREA 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.
Indoor unit
and outdoor
unit do not
operate.
• Replace the indoor electronic
control P.C. board.
No.
1
SymptomOperation indicator lamp Condition
Correspondence
Abnormal
point
0.5-second ON
0.5-second OFF
When the electricity is not conducted to the
interlock switch (Fan) of the horizontal vane. • Refer to 9-6.E"Check of
installation of the horizontal
vane".
Indoor unit
and outdoor
unit do not
operate.
Attachment
of the
horizontal
vane
All lamps flash at the same time.
No. SymptomOperation indicator lamp Condition
Correspondence
Abnormal
point
1
MXZ type
Operation
mode
setting
Outdoor unit
operates but
indoor unit
does not
operate.
When the operation mode of the each indoor
unit is differently set to COOL (includes DRY)
and HEAT at the same time, the operation
mode of the indoor unit that has operated at
first has the priority.
• Unify the operation mode.
Refer to outdoor unit service
manual.
2.5-second OFF
Both lamps flash
· Flashing of All lamps indicate abnormality.
· Flashing of AREA lamp(both lamps) indicates abnormality.
· POWER lamp is lighted.
Lighted
Blinking
Not lighted
· Flashing of PLASMA/WASH lamp indicates abnormality.
No.
1
SymptomOperation indicator lamp Condition
Correspondence
Abnormal
point
PLASMA/WASH lamp flashes.
2-time flash
2.5-second OFF
When PLASMA DEODORIZING power and/or
PLASMAAIR PURIFYING power can not be
turned OFF even if the PLASMA operation is
turned OFF with remote controller.
Indoor unit
and outdoor
unit do not
operate.
PLASMA
DEODORIZING/
PLASMA
AIR
PURIFYING
power control
•Refer to 9-6.F"Check of
PLASMA DEODORIZING
power" or 9-6.G"Check of
PLASMA AIR PURIFYING
power".
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20
9-5. Trouble criterion of main parts
MSZ-FA25VA MSZ-FA35VA
Part name FigureCheck method and criterion
Measure the resistance with a tester.
Refer to 9-7. "Test point diagram and voltage", "Indoor electronic control
P.C. board", the chart of thermistor.
Room temperature
thermistor(RT11)
Indoor coil thermistor
(RT12(MAIN), RT13(SUB))
Horizontal vane
motor(MV1) Normal
BRN-other one
Measure the resistance between the terminals with a tester.
(Part temperature 10°C ~ 30°C)
235 "~ 255 "
Color of the lead wire
Vertical vane
motor(MV2)
i-see Sensor
motor(MT) Normal
Measure the resistance between the terminals with a tester.
(Part temperature 10°C ~ 30°C)
Front panel
driving motor
(MP) Normal
Measure the resistance between the terminals with a tester.
(Part temperature 10°C ~ 30°C)
94 "~ 102 "
i-see Sensor(RR)
Turn the power ON(i-see Sensor is energized) with the aluminum block part
on the i-see Sensor P.C. board (upper part of i-see Sensor) covered with black
vinyl tape, then measure the voltage between connector terminals of i-see
Sensor using tester.
(Part temperature 10 ~ 40°C)
282 "~ 306 "
Normal range
2(-)
- 4(+)
1(+) - 2(-) 1.874 ~ 3.387V DC
1.010 ~ 1.420V DC
i-see Sensor
connector terminals
NOTE: Pay attention to static electricity.
Indoor fan motor(MF) Check 9-6. A.
PLASMA DEODORIZING/
PLASMAAIR PURIFYING
power
Check 9-6. For G.
Color of the lead wire
BRN-other one
Color of the lead wire
BRN-other one
RED
YLW
BRN
ORN GRN
ROTOR
RED
YLW
BRN
ORN GRN
ROTOR
RED
YLW
BRN
ORN GRN
ROTOR
i-see Sensor
Connector Black
vinyl tape
Aluminum block
i-see Sensor P.C. board
wThe aluminum block
part is covered with
black vinyl tape.
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