Logitech MSZ-A09NA, EDITION-B User Manual

Revision C:

• SPECIFICATION has been corrected.

Please void OB450 REVISED EDITION-B.

INDOOR UNIT

SERVICE MANUAL

Wireless type
Models

MSZ-A09NA MSZ-A24NA

No. OB450

REVISED EDITION-C

MSZ-A09NA -

1

MSZ-A24NA ­MSZ-A12NA MSY-A15NA
MSZ-A12NA -

1

MSY-A15NA ­MSZ-A15NA MSY-A17NA
MSZ-A15NA -

1

MSY-A17NA ­MSZ-A17NA MSY-A24NA
MSZ-A17NA -

MSZ-A09/12/15/17NA
MSY-A15/17NA

1

MSY-A24NA -

Outdoor unit service manual

MUZ-A·NA Series (OB451)
MXZ-A·NA Series (OB444)

CONTENTS

1. TECHNICAL CHANGES ··································· 2

2. PART NAMES AND FUNCTIONS ····················· 3

3. SPECIFICATION ················································ 4

4. OUTLINES AND DIMENSIONS ························ 6

5. WIRING DIAGRAM ············································ 8

6. REFRIGERANT SYSTEM DIAGRAM ··············· 9

7. SERVICE FUNCTIONS ··································· 10

8. TROUBLESHOOTING ······································11

9. DISASSEMBLY INSTRUCTIONS ···················· 25

10. PARTS LIST ····················································· 30
10-1. PARTS LIST ············································ 30
10-2. RoHS PARTS LIST ································· 36

11. MICROPROCESSOR CONTROL ···················· 42

1

1

1

1

NOTE:

RoHS compliant products have <G> mark on the spec name plate.
For servicing of RoHS compliant products, refer to the PARTS
LIST (RoHS compliant).

Revision A :

• PARTS LIST has been revised. (10-1.8, 10-2.8)

Revision B :

• MSZ-A•NA-1 and MSY-A•NA­ Remote controller has been changed.

1

Revision C :

• SPECIFICATION has been corrected.
Powerful has been added. (Airflow , Sound level)

1

MSZ09UN MSZ-A09NA
MSZ12UN MSZ-A12NA
MSH15TN MSZ-A15NA
MSH17TN MSZ-A17NA

1. Control method between indoor and outdoor has been changed.

2. Indoor fan motor has been changed.

3. Signal of remote controller has been changed. (It is not available for conventional models.)

MSZ-A09NA MSZ-A09NA-
MSZ-A12NA MSZ-A12NA-
MSZ-A15NA MSZ-A15NA-
MSZ-A17NA MSZ-A17NA-

1. Remote controller has been changed.

• Temperature indication function (°F/°C) has been added. (Refer to 11-10.)

Models Remote controller Temperature indication

MSZ-A09/12/15/17NA KM06A °F
MSZ-A09/12/15/17NA­MSZ-A24NA KM06B °F
MSZ-A24NA ­MSY-A15/17NA KM06C °F
MSY-A15/17NA ­MSY-A24NA KM06D °F
MSY-A24NA -

• Timer indication has been changed. (AM/PM indication)

2. Conduit plate has been removed. (MSZ-A09/12/15/17, MSY-A15/17)

3. Conduit cover, terminal block cover and terminal block holder have been changed. (MSZ-A09/12/15/17, MSY-A15/17)

TECHNICAL CHANGES

MSH24WN MSZ-A24NA
MS15TN MSY-A15NA
MS17TN MSY-A17NA
MS24WN MSY-A24NA

MSZ-A24NA MSZ-A24NA-

1

MSY-A15NA MSY-A15NA-

1

MSY-A17NA MSY-A17NA-

1

MSY-A24NA MSY-A24NA-

1

1

1

1

1

KM07J °F/°C

KM07K °F/°C

KM07L °F/°C

KM07M °F/°C

1

1

1

1

2

2

PART NAMES AND FUNCTIONS

MSZ-A09NA MSY-A15NA
MSZ-A12NA MSY-A17NA
MSZ-A15NA
MSZ-A17NA

Panel

Air cleaning filter
(Anti-Allergy Enzyme
Filter, Blue bellows
type)

Catechin air filter

Air outlet
Vertical vane

Horizontal vane

Line flow fan

MSZ-A09NA
MSZ-A12NA

Front panel

Air inlet

Heat exchanger

Operation section

(When the front panel is opened)

MSZ-A15NA
MSZ-A17NA
MSY-A15NA
MSY-A17NA

MSZ-A24NA
MSY-A24NA

Remote controller

Display section

Operation Indicator
lamp

Emergency operation switch

Remote control
receiving section

MSZ-A24NA
MSY-A24NA

Emergency operation switch

Operation indicator lamp

Remote control

receiving section

ACCESSORIES

MSZ-A09/12/15/17NA

MSY-A15/17NA

Installation plate 1 1 1
Installation plate fi xing screw 4 × 25 mm 8 5 7
Remote controller holder 1 1 1
Fixing screw for 3.5 × 1.6 mm (Black) 2 2 2
Battery (AAA) for remote controller 2 2 2
Wireless remote controller 1 1 1
Felt tape (Used for left or left-rear piping) 1 1 1
Conduit plate 1 – –

3

MSZ-A09/12/15/17NA-

MSY-A15/17NA- 1

1

MSZ-A24NA
MSY-A24NA

3

SPECIFICATION

Indoor unit model

External fi nish

Power supply V, phase, Hz

Max.-fuse size (time delay) / Disconnect switch A

Min. circuit ampacity A

Fan motor F.L.A

Airfl ow
Low–Med.–High–Powerful

Moisture removal pt./h

Sound level
Low–Med.–High–Powerful

Cond. drain connection O.D. in.

Dimensions

Weight Ib.

Remote controller

Control voltage (by built-in transformer)

Indoor unit model

External fi nish

Power supply V, phase, Hz

Max.-fuse size (time delay) / Disconnect switch A

Min. circuit ampacity A

Fan motor F.L.A

Airfl ow
Low–Med.–High–Powerful

Moisture removal pt./h

Sound level
Low–Med.–High–Powerful

Cond. drain connection O.D. in.

Dimensions

Weight Ib.

Remote controller

Control voltage (by built-in transformer)

COOL Dry (Wet)

HEAT

COOL

HEAT

W

D

H

COOL Dry (Wet)

HEAT

COOL

HEAT

W

D

H

CFM

dB(A)

in.

CFM

dB(A)

in.

MSZ-A09NA MSZ-A12NA

White

208/230, 1, 60

15

1.0

152-229-307-338

(134-205-275-303)

159-222-307-321 159-240-353-353

2.3 3.2

22-33-38-41 22-34-42-44

22-33-38-39 22-34-42-42

MSZ-A15NA MSY-A15NA MSZ-A17NA MSY-A17NA

268-328-381-419 (240-293-342-376)

254-314-381-381 — 254-314-381-381 —

4.7 5.1

34-40-45-47 34-40-46-48

34-38-44-44 — 34-38-44-44 —

0.76

5/8

30-11/16

8-/1/4

11-/3/4

23

Wireless type

12-24 VDC

White

208/230, 1, 60

15

1.0

0.76

5/8

30-/11/16

8-/1/4

11-/3/4

23

Wireless type

12-24 VDC

152-240-353-388

(134-215-318-349)

Indoor unit model

External fi nish

Power supply V, phase, Hz

Max.-fuse size (time delay) / Disconnect switch A

Min. circuit ampacity A

Fan motor F.L.A

Airfl ow
Low–Med.–High–Powerful

Moisture removal pt./h

Sound level
Low–Med.–High–Powerful

Cond. drain connection O.D. in.

Dimensions

Weight Ib.

Remote controller

Control voltage (by built-in transformer)

NOTE : Test conditions are based on ARI 210/240.

1 : Rating conditions (Cooling) — Indoor : 80˚FDB, 67˚FWB, Outdoor : 95˚FDB, (75˚FWB)
(Heating) — Indoor : 70˚FDB, 60˚FWB, Outdoor : 47˚FDB, 43˚FWB
2 : (Heating) — Indoor : 70˚FDB, 60˚FWB, Outdoor : 17˚FDB, 15˚FWB

COOL Dry (Wet)

HEAT

COOL

HEAT

W

D

H

CFM

dB(A)

in.

MSZ-A24NA MSY-A24NA

296-431-568-624 (265-385-508-558)

296-486-568-590 —

34-40-48-49 —

4

White

208/230, 1, 60

15

1.0

0.76

7.3

34-40-49-51

5/8

43-/5/16

10-/1/4

12-13/16

37

Wireless type

12-24 VDC

3-1. OPERATING RANGE

(1) POWER SUPPLY

Rated voltage Guaranteed Voltage (V)

Indoor unit

208/230 V

1 phase

60 Hz

Min.187

208 230 Max.253

(2) OPERATION

Intake air temperature (°F)

Mode Condition

Standard temperature 80 67 95 —

Cooling

Heating

Maximum temperature 90 73 115 —
Minimum temperature 67 57 14 —
Maximum humidity 78% —
Standard temperature 70 60 47 43
Maximum temperature 80 67 75 65
Minimum temperature 70 60 14 13

DB WB DB WB

Indoor Outdoor

3-2. OUTLET AIR SPEED AND COVERAGE RANGE

Model Mode Function Air fl ow (CFM)

HEAT Dry 307 16.8 23.4

MSZ-A09NA

MSZ-A12NA

MSZ-A15NA HEAT Dry 381 20.9 28.8
MSZ-A15NA

MSY-A15NA
MSZ-A17NA HEAT Dry 381 20.9 28.8
MSZ-A17NA

MSY-A17NA
MSZ-A24NA HEAT Dry 568 20.2 34.4
MSZ-A24NA

MSY-A24NA

COOL

HEAT Dry 353 19.3 26.7

COOL

COOL

COOL

COOL

Dry 307 16.8 23.4

Wet 275 15.1 21.0

Dry 353 19.3 26.7

Wet 318 17.4 24.1

Dry 381 20.9 28.8

Wet 342 18.8 26.0

Dry 381 20.9 28.8

Wet 342 18.8 26.0

Dry 568 20.2 34.4

Wet 508 18.1 30.9

Air speed

(ft./sec.)

Coverage
range (ft.)

● The air coverage range is the

fi gure up to the position where
the air speed is 1 ft./sec., when
air is blown out horizontally
from the unit properly at the
High speed position.
The coverage range should be
used only as a general guide­line since it varies according to
the size of the room and furni­ture arranged inside the room.

5

4

OUTLINES AND DIMENSIONS

MSZ-A09NA MSY-A15NA
MSZ-A12NA MSY-A17NA
MSZ-A15NA
MSZ-A17NA

30-11/16

11-3/4

Conduit plate(MSZ-A•NA- and MSY-A•NA- are excluded.)

7/16x1 Oblong hole

Installation plate

Indoor unit

7/16x13/16

2-3/16 2-3/16

10-1/8

1-5/8 8-7/16

2-3/16

13-3/16 12-5/8

Air in

8-1/4

Oblong hole

8-7/8 8-7/8

7/8

6-1/8 6-1/8

3/16

Installation plate

hole

1-3/4

{

Unit : inch

9/1610-3/4

7/8

8-7/16

9-3/16

11-5/16

2-3/4

Wall hole 2-9/16

Liquid line 1/4 19-11/16
Gas line 3/8 16-15/16
Insulation 1-3/8 O.D
3/4 I.D

1/8

1-11/16

2-1/8

2-5/16

6-1/4

3/4

Drain hose 5/8

424-9/16

Air out

(Connected part O.D)
Insulation 1-1/8

6

MSZ-A24NA
MSY-A24NA

Unit : inch

12-13/16

2-3/16

2-5/16

42-1/16

43-5/16

31-1/8

3/4

9-15/16

Installation plate

3-7/8

1-7/8

3-7/8 6-13/16

Air in

16-5/16 16-5/16

Wall hole 3

10-1/4

Air out

3/16

Indoor unit

Installation plate

Liquid line 1/4 19-11/16
Gas line 5/8 16-15/16

{

Insulation 1-15/16 O.D

Drain hose 5/8
(Connected part O.D)

Insulation 1-1/8

6-13/16

1-1/4 I.D

1/8

10-1/161-7/8

5/16

12-3/8

6-1/4

Wireless remote controller

7

5

MSZ-A09NA MSY-A15NA
MSZ-A12NA MSY-A17NA
MSZ-A15NA
MSZ-A17NA

WIRING DIAGRAM

MSZ-A24NA
MSY-A24NA

8

6

REFRIGERANT SYSTEM DIAGRAM

MSZ-A09NA
MSZ-A12NA

Indoor
heat
exchanger

Room temperature
thermistor
RT11

Indoor coil
thermistor
RT12(main)

Indoor coil
thermistor
RT13(sub)

Refrigerant pipe ø3/8
(with heat insulator)

Flared connection

Flared connection

MSZ-A15NA MSY-A15NA
MSZ-A17NA MSY-A17NA

Refrigerant pipe ø1/2
(with heat insulator)

Indoor
heat
exchanger

Room temperature
thermistor
RT11

Indoor coil
thermistor
RT12(main)

Distributor

Indoor coil
thermistor
RT13(sub)

Flared connection

Flared connection

Unit : inch

MSZ-A24NA
MSY-A24NA

Indoor
heat
exchanger

Indoor coil
thermistor
RT13(sub)

Room temperature
thermistor
RT11

Indoor coil
thermistor
RT12(main)

Distributor

Refrigerant pipe ø1/4
(with heat insulator)

Refrigerant pipe ø5/8
(with heat insulator)

Flared connection

Flared connection

Refrigerant pipe ø1/4
(with heat insulator)

Refrigerant pipe ø1/4
(with heat insulator)

Refrigerant flow in cooling

Refrigerant flow in heating

9

7

SERVICE FUNCTIONS

MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSZ-A24NA
MSY-A15NA MSY-A17NA MSY-A24NA

7-1. TIMER SHORT MODE

For service, set time can be shortened by short circuit of JPG and JPS the indoor 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.)

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.

How to modify the remote controller P.C. board

Remove batteries before modification.
The board has a print as shown below :

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

J1

J2

press the RESET button.

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.

Table 1

1 unit operation 2 units operation 3 units operation 4 units operation

No. 1 unit No modifi cation Same as at left Same as at left Same as at left
No. 2 unit — Solder J1 Same as at left Same as at left
No. 3 unit — — Solder J2 Same as at left
No. 4 unit — — — Solder both J1 and J2

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.

10

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

If the main power has been cut, the operation settings remain.
After 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”

Turn off the main power of the unit.
Solder the Jumper wire JR07 on the indoor electronic control P.C. board. (Refer to 8-7.)

MSZ-A09/12/15/17NA
MSY-A15/17NA

JR07

BZ

CN151 CN211CN112

MSZ-A24NA
MSY-A24NA

JR07

BZ

CN101

CN211CN112

CN152

CN151

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.

8

TROUBLESHOOTING

MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSZ-A24NA
MSY-A15NA MSY-A17NA MSY-A24NA

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 miswiring.

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.

Lead wiring

Housing point

11

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.

Remove the front lid and insert batteries.

Then reattach the front lid.

Insert the negative pole of the
batteries first. Check if the polarity
of the batteries is correct.

Press RESET button with tip end of ball point pen

or the like, and then use the remote controller.

RESET button

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.

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 cannot operate, indicating as shown in the figure below. In this case, please set all the indoor
units to the same operation mode.

OPERATION INDICATOR

Lighted
Blinking
Not lighted

• When indoor unit starts 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.

12

8-2. FAILURE MODE RECALL FUNCTION

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.

1. Flow chart of failure mode recall function for the indoor/outdoor unit

Operational procedure

The cause of abnormality cannot be found because the abnormality doesn't recur.

Setting up the failure mode recall function

Turn ON the power supply.
<Preparation of the remote controller>

While pressing both OPERATION SELECT button and TOO COOL button on the

remote controller at the same time, press RESET button.

First, 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.

Those figures show about MSZ-A09/12/15/17.

Press OPERATE/STOP (ON/OFF) button of the remote controller (the set temperature
is displayed) with the remote controller headed towards the indoor unit.

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 emit-

ted at the same timing as the blinking of the left lamp
of OPERATION INDICATOR lamp. 2

Yes

Judgment of indoor/outdoor abnormality

Releasing the failure mode recall function

Deleting the memorized abnormal condition

NOTE: 1. 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.

Before blinking, does the left 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 confi rm the abnormal point with the indoor unit
failure mode table. (8-2.2.)
Make sure to check at least two consecutive blinking cycles.

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.

Repair the defective parts.

After repairing the unit, recall the failure mode again according to "Setting up the failure mode recall

function" mentioned above.

Press OPERATE/STOP (ON/OFF) button of the remote controller (the set temperature is displayed)

with the remote controller headed towards the indoor unit.
Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted.
Release the failure mode recall function according to "Releasing the failure mode recall function"

mentioned above.

(Blinks)

No

1

1. Regardless of normal or abnormal condition, a short

Indoor unit is normal.
But the outdoor unit might be abnormal because there are some abnor-

No
(OFF)

Yes

2

malities that can't be recalled with this way.
Confi rm 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 confi rm 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.

beep is emitted once the signal is received.

3

2. Blinking pattern when the indoor unit is abnormal:
Blinking at 0.5-

2.5-second OFF

second interval

2.5-second OFF

ON

OFF

Beeps

Repeated cycle Repeated cycle

3.Blinking pattern when the outdoor unit is abnormal:

2.5-second OFF 3-second ON

ON

OFF

No beep Beeps

Repeated cycle

Blinking at 0.5­second interval

Blinking at 0.5­second interval

Beeps

2.5-second OFF 3-second ON

13

Beeps

Repeated cycle

Blinking at 0.5­second interval

No beep Beeps

Repeated cycle

Repeated cycle

2. Indoor unit failure mode table

Left lamp of OPERATION

INDICATOR lamp

Not lighted Normal — —

1-time fl ash every

0.5-second

2-time fl ash

2.5-second OFF
3-time fl ash

2.5-second OFF

11-time fl ash

2.5-second OFF

12-time fl ash

2.5-second OFF

Abnormal point

(Failure mode)

Room temperature
thermistor

Indoor coil
thermistor

Serial signal

Indoor fan motor

Indoor control
system

Condition Correspondence

The room temperature thermistor short or
open circuit is detected every 8 seconds dur­ing operation.

The indoor coil thermistor short or open circuit
is detected every 8 seconds during operation.

The serial signal from outdoor unit is not re­ceived for a maximum of 6 minutes.

The rotational frequency feedback signal is
not emit during the 12 seconds the indoor fan
operation.

It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.

Refer to the characteristics of the room temperature
thermistor (8-7.).

Refer to the characteristics of the main indoor coil ther­mistor, the sub indoor coil thermistor (8-7.).

Refer to 8-6.
signal error".

Refer to 8-6. "Check of indoor fan motor".

Replace the indoor electronic control P.C. board.

"How to check miswiring and serial

NOTE : Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (8-4.).

14

8-3. INSTRUCTION OF TROUBLESHOOTING

Start

Indoor unit oper­ates.
Outdoor unit
doesn't operate.

Outdoor unit
operates only
in Test Run
operation.

Check room
temperature
thermistor.
Refer to 8-7.
"Test point
diagram and
voltage".

Outdoor
unit doesn't
operate even
in Test Run
operation.

Refer to "How
to check
inverter/com­pressor".

Indoor unit operates.
Outdoor unit doesn't
operate normally.

Unit doesn't
operate nor­mal operation
in COOL or
HEAT mode.

Refer to
"Check of R.V.
coil".

Indoor unit
doesn't receive
the signal from
remote controller.

Indoor unit
operates, when
EMERGENCY
OPERATION
switch is pressed.

Refer to 8-6.
"Check of remote
controller and
receiver P.C.
board".

OPERATION INDICATOR
lamp on the indoor unit is
fl ashing on and off.

Indoor unit
doesn't operate,
when EMER­GENCY OPERA­TION switch is
pressed.

1. Check indoor/out­door connecting wire.
(Check if the power is
supplied to the indoor
unit.)

2. Refer to 8-6. "Check
of indoor electronic
control P.C. board and
indoor fan motor".

If blinking of OPERATION INDI­CATOR lamp cannot be checked,
it can be checked with failure
mode recall function.

"Test Run operation" means

the operation within 30 minutes
after EMERGENCY OPERA­TION switch is pressed.

Refer to outdoor unit service manual.

Left lamp
Flash on and
off at 0.5-sec­ond intervals
Cause:
Indoor/Outdoor
unit

• Miswiring or
trouble of
serial signal

Refer to 8-6.

"How to
check mis­wiring and
serial signal
error".

Left lamp
2-time fl ash
Cause:
Indoor unit

• Trouble
of room
temperature
/ indoor coil
thermistor

Check room
temperature
thermistor
and indoor
coil thermis­tor. Refer
to 8-7."Test
point diagram
and voltage".

Left lamp
3-time fl ash
Cause:
Indoor unit

• Trouble of
indoor fan
motor

Refer to 8-6.

"Check of
indoor fan
motor".

Left lamp
4-time fl ash
Cause:
Indoor unit

• Trouble
of indoor
unit control
system

Replace the
indoor elec­tronic control
P.C. board.

15

Left lamp
5-time fl ash
Cause:
Outdoor unit

• Outdoor
power
system
abnormality

Refer to
"How to
check
inverter/com­pressor".

Left lamp
6-time fl ash
Cause:
Outdoor unit

• Trouble of
thermistor in
outdoor unit

Refer to
"Check of
outdoor ther­mistors".

Left lamp
7-time fl ash
Cause:
Outdoor unit

• Trouble of
outdoor con­trol system

Replace the
inverter P.C.
board or
the outdoor
electronic
control P.C.
board.

Left lamp
14-time fl ash
Cause:
Outdoor unit

• Other ab­normality

Check "Flow
chart of the
detailed
outdoor unit
failure mode
recall func­tion."

8-4. TROUBLESHOOTING CHECK TABLE

Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
When the indoor unit has started operation and detected an abnormality of the following condition (the first detection after the
power ON), the indoor fan motor turns OFF and OPERATION INDICATOR lamp flashes.

OPERATION INDICATOR

Abnormal

No.

1

2

3

4

5

6

point

Miswiring
or serial
signal

Indoor coil
thermistor

Room tem­perature
thermistor

Indoor fan
motor

Indoor con­trol system

Outdoor
power sys­tem

Outdoor
thermistors

Left lamp fl ashes.

0.5-second ON

0.5-second OFF

Left lamp fl ashes.
2-time fl ash

2.5-second OFF

Left lamp fl ashes.
3-time fl ash

2.5-second OFF

Left lamp fl ashes.
4-time fl ash

2.5-second OFF

Left lamp fl ashes.
5-time fl ash

2.5-second OFF

Left lamp fl ashes.
6-time fl ash

2.5-second OFF

Operation indicator lamp Symptom Condition Correspondence

Lighted
Blinking
Not lighted

Refer to 8-6. "How to check

Indoor unit and
outdoor unit do
not operate.

The serial signal from the outdoor unit is not
received for 6 minutes.

The indoor coil or the room temperature ther­mistor is short or open circuit.

The rotational frequency feedback signal is
not emitted during the indoor fan operation.

It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.

It consecutively occurs 3 times that the com­pressor stops for overcurrent protection or
start-up failure protection within 1 minute after
start-up.

The outdoor thermistors short or open circuit
during the compressor operation.

•
miswiring and serial signal er­ror".

Refer to 8-7. the characteristics

•
of indoor coil thermistor, and
the room temperature thermis­tor.

Refer to 8-6. "Check of in-

•
door fan motor".

Replace the indoor electronic

•
control P.C. board.

Refer to "How to check of in-

•
verter/compressor".
Refer to outdoor unit service
manual
Check the stop valve.

•

Refer to "Check of outdoor

•
thermistor".
Refer to outdoor unit service
manual.

Outdoor

7

control sys­tem

Other ab-

8

normality

Outdoor
control
system

9

MSZ-A09/12
/15/17
MSY-A15/17

Left lamp fl ashes.
7-time fl ash

2.5-second OFF

Left lamp fl ashes.
14-time fl ash

2.5-second OFF

Left lamp lights up

Outdoor unit
does not oper­ate

It cannot properly read data in the nonvolatile
memory of the inverter P.C. board or the out­door electronic control P.C. board.

An abnormality other than above mentioned
is detected.

It cannot properly read data in the nonvolatile
memory of the inverter P.C. board or the out­door electronic control P.C. board.

16

Replace the inverter P.C. board

•
or the outdoor electronic con­trol P.C. board.
Refer to outdoor unit service
manual.

Check the stop valve.

•
Confi rm the abnormality in

•
detail using the failure mode
recall function for outdoor unit.

Check the blinking pattern of

•
the LED on the inverter P.C.
board or the outdoor electronic
control P.C. board.

OPERATION INDICATOR

Abnormal

No.

1

point

MXZ type

Operation
mode
setting

Left lamp lights and lower lamp fl ashes.
Lower lamp fl ashes.

2.5-second OFF

Operation indicator lamp Symptom Condition Correspondence

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 fi rst has
the priority.

Outdoor unit
operates but
indoor unit does
not operate.

8-5. TROUBLE CRITERION OF MAIN PARTS

MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSZ-A24NA
MSY-A15NA MSY-A17NA MSY-A24NA

Part name Check method and criterion Figure

Unify the operation mode.

•
Refer to outdoor unit service
manual.

Room temperature
thermistor(RT11)

Measure the resistance with a tester.

Refer to 8-7. "Test point diagram and voltage",

Indoor coil thermistor

"Indoor electronic control P.C. board", the chart of thermistor..

(RT12(MAIN),RT13(SUB))

Indoor fan motor(MF) Check 8-6. .

Measure the resistance between the terminals with a tester.

Horizontal vane
motor(MV)

MSZ-A09/12/15/17NA
MSY-A15/17NA

Horizontal vane
motor(MV1)
Vertical vane
motor(MV2)

MSZ-A24NA

(Part temperature 50 ~ 86°F)

Color of the lead wire Normal

BRN-other one 235 ~ 255 Ω

Measure the resistance between the terminals with a tester.
(Part temperature 50 ~ 86°F)

Color of the lead wire Normal

BRN-other one 282 ~ 306 Ω

MSY-A24NA

RED

YLW
BRN

RED

YLW

BRN

ROTOR

ORN

ROTOR

ORN

GRN

GRN

17

8-6. TROUBLESHOOTING FLOW

A Check of indoor fan motor

The indoor fan motor error has occurred, and the indoor fan doesn't operate.

Turn OFF the power supply.

Is there any foreign matter that interferes
the rotation of the line fl ow fan?

Yes

Remove the foreign matter and
adjust the line fl ow fan.

Is there 294/325 VDC between

(+) and (-), and does the

CN211
voltage between CN211
rise to the range of 3 to 6 VDC within
12 seconds after EMERGENCY
OPERATION switch is pressed?

No

Replace the indoor electronic control P.C. board.

No

(+) and (-)

Pay careful attention to the high voltage on the fan motor connector CN211.

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.

1. Measure the voltage between CN211 (+) and (-).

2. Measure the voltage between CN211

If more than 12 seconds passes after EMERGENCY OPERATION switch

is pressed, the voltage mentioned above 2 goes 0 VDC although the
indoor electronic control P.C. board is normal

Yes

Replace the indoor fan motor.

(+) and (-).

Indoor electronic
control P.C. board

CN211

The indoor fan motor error has occurred, and the indoor fan repeats "12-second ON and 30-second OFF" 3 times, and then stops.

Measure the voltage between CN211

(+) and (-) while the fan motor is

rotating.

Is it unchanged holding
0 or 15 VDC?

Yes
(Unchanged)

Replace the indoor fan motor.

No
(Changed)

Replace the indoor electronic control P.C. board.

18

B Check of remote controller and indoor electronic control P.C. board

Check if the remote controller is exclusive for this air conditioner.

Press OPERATE/STOP (ON/OFF)

button on the remote controller.

Is LCD display on the remote controller
visible?

Yes

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.

Does the unit operate with the remote
controller?

Yes

OK

MSZ-A24NA
MSY-A24NA

Measure the voltage between receiver
P.C. board connector CN301 No.2(+) and
No.3(-) when the remote controller button
is pressed.

No
(Not clear)

No

Replace the batteries. (Refer to 8-1.4.)

Turn ON a radio to AM and press OP­ERATE/STOP (ON/OFF) button on the
remote controller.

Is noise heard from radio?

Yes

Are there any fl uorescent lights of
inverter or rapid-start type within the
range of 3.28 ft.?

No

No

Yes

Replace the remote controller.

Reinstall the unit away from lights.

•

Attach a fi lter on receiving part.

•

MSZ-A09/12/15/17NA
MSY-A15/17NA

Is the voltage approx. 4 VDC?

No (5 or 0 VDC)

Replace the receiver P.C. board.

Yes

Replace the indoor electronic control
P.C. board.

19

C Check of indoor electronic control P.C. board and indoor fan motor

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.

Does the unit operate with the remote
controller? Does OPERATION INDICATOR
lamp light up by pressing EMERGENCY
OPERATION switch?

No

Turn OFF the power supply.
Check both “parts side” and “pattern
side” of the indoor electronic control
P.C. board visually.

Measure the resistance between
CN211 and of the indoor fan motor
connector.

Yes

Measure the resistance of the horizon­tal vane motor coil.
(Refer to 8-5.)

Replace the indoor
electronic control P.C. board.

Yes

Are the varistor (NR11)
burnt and the fuse (F11)
blown?

Be sure to check both the fuse
and the varistor in any case.

Is the fuse (F11) blown
only?

Yes

Measure the resistance between
(+) and (-) of the indoor fan motor
connector (to CN211 on the indoor
electronic control P.C. board).

No

No

1, 2

Short/open circuit:
Replace the indoor fan motor.

Short/open circuit:
Replace the horizontal vane motor and the
indoor electronic control P.C. board.

1. The fan motor connector's lead wire is red, whereas is
black.

2. Connect "+" of the tester to fan motor connector's lead
wire, and "-" to lead wire, otherwise the resistance can­not be measured properly.

Indoor electronic
control P.C.Board

Measure the resistance of cement
resistor (R111) on the indoor elec­tronic control P.C. board.

Varistor(NR11)
Fuse(F11)
CN211

Is the resistance 1 MΩ
or more?

Yes

Replace indoor electronic control
P.C. board.

Replace the indoor electronic control P.C. board.

Is the resistance approx.
4 Ω?

20

Replace indoor electronic control P.C. board

No

and the indoor fan motor.

Replace the indoor electronic control P.C.
board and the indoor fan motor.

No

Yes

D How to check miswiring and serial signal error

Turn OFF the power supply.

Is there rated voltage in the
power supply?

Yes

Turn ON the power supply.

Is there rated voltage between
outdoor terminal block S1 and
S2?

Press EMERGENCY OPERATION switch once.

Does the left lamp of OPERATION INDICA­TOR lamp light up? <Confi rmation of the
power to the indoor unit>

Is serial signal error indicated 6 minutes later?

Turn OFF the power supply.
Check once more if the indoor/outdoor

B

connecting wire is not miswiring.
Short-circuit outdoor terminal block S2
and S3.

Turn ON the power supply.

Yes

Yes

Yes

A

1

No

No

Check the power supply.

Check the wiring.

No

Is there any miswiring, poor
contact, or wire disconnec-

No

tion of the indoor/outdoor
connecting wire?

No

1. Miswiring may damage indoor electronic control P.C.
board during the operation.

Be sure to confi rm the wiring is correct before the opera-

tion starts.

3. 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)

Yes

Correct them.

A

Turn OFF inverter-controlled lighting

•
equipment.
Turn OFF the power supply and then

•
turn ON again.
Press EMERGENCY OPERATION

•
switch.

Reinstall

•
either the unit
or the light
each other

No

•

away.
Attach a fi lter
on remote
control
receiving
section of the
indoor unit.

Is serial signal
error indicated 6
minutes later?

Yes

B

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-second­ON quick blinking"? 3

Yes

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 20 VDC
between outdoor terminal block S2 and
S3? <Confi rmation of serial signal>

Yes

Is there rated voltage between
indoor terminal block S1 and S2?
<Confi rmation of power voltage>

Yes

Replace the indoor electronic control P.C. board.

Be sure to release the failure-mode recall function
after checking.

No
(Lighted
or not
lighted)

No

No

21

Replace the inverter P.C. board or
the outdoor electronic control P.C. board.

2

2. Be careful to the residual
voltage of smoothing capacitor.

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?

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

No

Replace the indoor/
outdoor connecting

Yes

wire.

Replace the indoor/
outdoor connecting

Yes

wire.

E Electromagnetic noise enters into TV sets or radios

Is the unit grounded?

Yes

Is the distance between the antennas
and the indoor unit within 9.91 ft., or is
the distance between the antennas and
the outdoor unit within 9.91 ft.?

No

Is the distance between the TV sets or
radios and the indoor unit within 3.28
ft., or is the distance between the TV
sets or radios and the outdoor unit
within 9.91 ft.?

No

Are the antennas damaged?
Is the coaxial cable damaged?
Is there any poor contact in the anten­na wiring?

No

Is the indoor/outdoor connecting wire of
the air conditioner and the wiring of the
antennas close?

No

Yes

Yes

Yes

Yes

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.

Replace or repair the antenna.
Replace or repair the coaxial cable.

Extend the distance between the indoor/outdoor
connecting wire of the air conditioner and the wir­ing of the antennas.

No

Even if all of the above conditions are fulfi lled, the electromagnetic noise may enter, depending on the electric fi eld strength
or the installation condition (combination of specifi c 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 fi eld intensity of the broadcast station affected by the electromagnetic noise

6. Presence or absence of amplifi er 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.

22

8-7. Test point diagram and voltage

MSZ-A09NA MSZ-A12NA MSZ-A15NA
MSZ-A17NA MSY-A15NA MSY-A17NA

Indoor electronic control P.C. board

Varistor (NR11)

Cement
resistor
(R111 )

Release of Auto restart
function
Solder the Jumper wire
to JR07
(Refer to 7-3.)

Power supply input

208/230 VAC Fuse (F11)

}

250 V 3.15 A

Indoor fan motor
(CN211)

294/325 VDC

(-) Fiducial terminal of
cathode side on measur­ing high-voltage DC

15

VDC

(+)3-6 VDC

(+)0 or 15 VDC

Power monitor
receiver P.C.
board

Emergency
operation switch

SW P.C. board

12 VDC

5 VDC

Indoor coil thermistor
RT12(MAIN)
RT13(SUB)
(CN112)

Horizontal vane
motor(CN151)

Room temperature
thermistor (RT11)

Timer short mode

}

point JPG, JPS
(Refer to 7-1.)

Indoor coil thermistor [RT12 (MAIN), RT13 (SUB)]
Room temperature thermistor (RT11)

23

Resistance (k )

Temperature (°F)

MSZ-A24NA MSY-24NA

Indoor electronic control P.C. board

Release of Auto restart
function
Solder the Jumper wire
to JR07
(Refer to 6-3.)

Display
P.C.
board

Cement
resistor
(R111 )

Varistor (NR11)

Power supply input

208/230 VAC Fuse (F11)

}

250 V 3.15 A

Indoor fan motor
(CN211)

294/325 VDC

(-) Fiducial terminal of
cathode side on measur­ing high-voltage DC

15

VDC

(+)3-6 VDC

(+)0 or 15 VDC

5 VDC

Receiver
P.C. board

SW P.C. board

12 VDC

Indoor coil thermis­tor RT12(MAIN)
RT13(SUB)

Horizontal vane
motor (CN151)

Room temperature
thermistor (RT11)

Timer short
mode point

}

JPG, JPS

Vertical vane motor (CN152)

Indoor coil thermistor [RT12 (MAIN), RT13 (SUB)]
Room temperature thermistor (RT11)

Resistance (k )

(Refer to 7-1.)

24

Temperature (°F)

9

DISASSEMBLY INSTRUCTIONS

<"Terminal with locking mechanism" Detaching points>

The terminal which has the locking mechanism can be detached as shown below.
There are two types ( Refer to (1) and (2)) of the terminal with locking mechanism.
The terminal without locking mechanism can be detached by pulling it out.
Check the shape of the terminal before detaching.

(1) Slide the sleeve and check if there is a locking lever or not.

Sleeve

Slide the sleeve.
Pull the terminal while

Locking lever

pushing the locking
lever.

(2) The terminal with this connector has the
locking mechanism.

Hold the sleeve, and
pull out the terminal
slowly.

Connector

9-1. MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSY-A15NA MSY-A17NA

OPERATING PROCEDURE PHOTOS

1. Removing the panel

(1) Remove the horizontal vane.
(2) Remove the screw caps of the panel. Remove the

screws. (Photo 1)

(3) Hold the lower part of both ends on the panel and pull

it slightly toward you, and then remove the panel by
pushing it upward.

Photo 3

Photo 1

Screws of the panel

MSZ-A09/12/15/17NA ­MSY-A15/17NA -

1

Screw of the
conduit cover

Terminal block
cover

Horizontal vane

Photo 2

Conduit cover

Terminal block
cover

Conduit cover

1

MSZ-A09/12/15/17NA
MSY-A15/17NA

25

Screw of the
conduit cover

Conduit plate

OPERATING PROCEDURE

PHOTOS

2. Removing the electronic control P.C. board, the
power monitor receiver P.C. board, SW P.C. board
and the terminal block

(1) Remove the horizontal vane, the panel (refer to 1.) and the

corner box.

(2)

Remove the screw of the conduit cover, and conduit cover.

(Photo 2 or Photo 3)
(3) Remove the indoor/outdoor connecting wire.
(4) Remove the switch holder from the electrical cover. (Photo

4)

(5) Remove the screw of the electrical cover, and then the

electrical cover. (Photo 4)
(6) Remove the ground wire connected to the indoor electronic

control P.C. board from the electrical box. (Photo 5)
(7) Unhook the power monitor receiver P.C. board holder from

the catch. (Photo 4)
(8) Open the rear cover of the power monitor receiver P.C.

board holder and pull out the power monitor receiver P.C.

board.
(9) Open the switch holder and pull out SW P.C. board.
(10)

Pull the electronic control P.C. board slightly toward you

from the electrical box, and disconnect TAB3 and all the

connectors on the electronic control P.C. board. (LD101

and LD105 are direct-mounted to the electronic control P.C.

board.)
(11)

Pull out the electronic control P.C. board from the electrical

box.
(12)

Remove the ground wire connected to the heat exchanger

from the electrical box. (Photo 5)
(13)

Unhook the catches of the electrical box, and pull out the

electrical box.
(14)

Remove the screw of the terminal block cover, and then

remove the terminal block cover and the terminal block

holder. (Photo 6)
(15)

Remove the terminal block by sliding it.

Photo 4

Photo 5

Switch holder

Screw of the
electrical cover.

Power monitor
receiver
P.C. board holder

Ground wire

Indoor fan motor
connector (CN211)

Indoor coil thermistor
connector (CN112)

Vane motor
connector (CN151)

3. Removing the electrical box

(1) Remove the horizontal vane, the panel (refer to 1.) and the

corner box.

(2) Remove the screw of Conduit cover, and then the indoor/

outdoor connecting wire. (Photo 2 or
(3) Remove the switch holder and the electrical cover. (Photo 4)
(4) Remove the ground wire connected to the heat exchang-

er from the electrical box. (Photo 5)
(5) Disconnect the following connectors on the electronic

control P.C. board; the fan motor connector <CN211>, the

indoor coil thermistor connector <CN112>, the vane motor

connector <CN151>. (Photo 5)
(6) Unhook the catches of the electrical box, and pull out the

electrical box.

Photo 3

)

Photo 6

Screw

26

OPERATING PROCEDURE

PHOTOS

4. Removing the horizontal vane motor unit

(1) Remove the horizontal vane, the panel (refer to 1.) and the

corner box.

(2) Remove the screws of the horizontal vane motor unit, and

pull out the horizontal vane motor unit. (Photo 7)

(3) Disconnect the connector from the horizontal vane motor

unit.

5. Removing the indoor fan motor and the line flow fan

(1) Remove the horizontal vane, the panel (refer to 1.) and the

corner box.

(2)

Remove the switch holder and the electrical box. (Refer to 3.)

(3)

Remove

remove the nozzle assembly.
(4) Remove the screws fixing the motor bed.
(5) Loosen the screw fixing the line flow fan.
(6) Remove the motor bed together with fan motor and motor

band.
(7) Release the hooks of the motor band, and remove the

motor band then pull out the indoor fan motor.
(8) Remove the screws fixing the left side of the heat exchang-

er.
(9) Lift the heat exchanger, and pull out the line flow fan to the

lower-left.

the drain hose from the nozzle assembly, and

(Photo 8)

(Photo 9)

(Photo 10)

Photo 7

Photo 8

Screws of
the motor
bed

Screws of the
horizontal vane
motor unit

Motor band

Photo 9

Screw of
the line flow
fan

Photo 10

Screws of the
left side of the
heat exchanger

27

9-2.MSZ-A24NA MSY-A24NA

OPERATING PROCEDURE

1. Removing the front panel

(1) Remove the screw caps of the front panel. Remove the

screws.

(2) Pull the panel down to your side slightly and unhook the

catches at the top.

2. Removing the electronic control P.C. board, the receiver
P.C. board and the display P.C. board

(1) Remove the front panel. (Refer to 1.)
(2) Remove the corner box
(3) Remove the screw of the electrical cover.

Remove the electrical cover and T.B. SW cover.
(4) Remove the screw of the ground wire, which is solder-

mounted to the electronic control P.C. board.
(5) Remove the R.L holder.
(6) Remove the screw of the conduit cover.
(7) Remove the conduit cover.
(8) While pulling the electronic control P.C. board forward little

by little, disconnect all the connectors from the board.
(9) Remove the electronic control P.C. board.
(10) Open the R.L holder, remove the receiver P.C. board and

the display P.C. board.

Photo 1

Photo 2

PHOTOS

Front panel

Screws

Screw of the ground wire

Corner box

Indoor
electronic
control
P.C. board

T.B. SW cover

Screw of
T.B. SW cover

Screw of the
electrical cover

3. Removing the electrical box

(1) Remove the front panel. (Refer to 1.)
(2) Remove the electrical cover. (Refer to 2.)
(3) Disconnect the connector of the indoor coil thermistors.
(4) Disconnect the indoor fan motor connector (CN211) and

the vane motor connector (CN151 and CN152) on the elec-

tronic control P.C. board.
(5) Remove the screw of ground wire to the heat exchanger.
(6) Remove the fan motor lead wire and indoor coil thermistor

from the electrical box.
(7) Remove the lead wire of vane motor from the bottom of

electrical box.
(8) Remove the screw fixing the electrical box and remove the

electrical box.

28

Photo 3

R.L
holder

Screw of
conduit cover

Screw of the
ground wire

Conduit cover

Receiver
P.C. board

Screw of the
electrical box

OPERATING PROCEDURE

PHOTOS

4. Removing the vane motor

(1) Remove the front panel. (Refer to 1.)
(2) Remove the electrical cover. (Refer to 2.)
(3) Remove the lead wire of vane motor. (Refer to 3.)
(4) Remove the R.L. holder.
(5) Pull out the drain hose from the nozzle assembly and remove

the nozzle assembly.

(6) Remove the screws of the vane motor and disconnect the

connector.

(7) Remove the vane motor.

Photo 5

Screws of the
vane motor

Vane motor

5. Removing the line flow fan and the indoor fan motor

(1) Remove the front panel. (Refer to 1.)
(2) Remove the electrical box. (Refer to 3.)
(3) Remove the drain hose from the nozzle assembly and

remove the nozzle assembly.
(4) Remove the water cut.
(5) Slide the hole cover and remove the hole cover.
(6) Remove the hexagon socket set screw from the line flow fan.
(7) Remove the screws fixing the motor bed and remove the fan

motor. (Be careful not to drop the fan motor because it is

heavy.)
(8) Remove the screws fixing the left side of the heat exchang-

er.
(9) Lift the left side of the heat exchanger.
(10) Remove the line flow fan.

Photo 4

Vane motors

Photo 6

Screws fixing
the left side
of the heat
exchanger

Photo 7

Screws
of the
vane
motor

Photo 8

Hole
cover

Water cut

Screws of the motor bed

29

10 PARTS LIST

10-1. PARTS LIST (non-RoHS compliant)
MSZ-A09NA MSY-A15NA
MSZ-A12NA MSY-A17NA
MSZ-A15NA
MSZ-A17NA

1. INDOOR UNIT STRUCTURAL PARTS

1

2. ACCESSORY AND REMOTE

9

CONTROLLER

10

11

12

8

2

7
(See 10-1.5.)

3

4

5

6

1. INDOOR UNIT STRUCTURAL PARTS

No. Part No. Part name

1 E02 A32 234 BOX 1 1 1 1 1 1
2 E02 A49 000 PANEL ASSEMBLY 1 1 1 1 1 1
3 E02 913 067 SCREW CAP 2 2 2 2 2 2 2 PC/SET
4 E02 915 010 FRONT PANEL 1 1 1 1 1 1
5 E02 915 100 CATECHIN AIR FILTER (LEFT) 1 1 1 1 1 1
6 E02 916 100 CATECHIN AIR FILTER (RIGHT) 1 1 1 1 1 1
7 — AIR CLEANING FILTER 1 1 1 1 1 1 MAC-415FT-E
8 E02 A32 975 CORNER BOX (RIGHT) 1 1 1 1 1 1
9 E02 913 970 INSTALLATION PLATE 1 1 1 1 1 1

10 E02 A49 978 CONDUIT PLATE 1 1 1 1 1 1

Symbol

in Wiring

Diagram

A09NA A12NA A15NA A17NA A15NA A17NA

Q'ty/unit

MSZ- MSY-

Remarks

Including No.3,4

2. ACCESSORY AND REMOTE CONTROLLER

E02 A54 426

11

E02 A49 426 1 1 KM06C

12 E02 527 083

REMOTE CONTROLLER

REMOTE CONTROLLER
HOLDER

1 1 1 1 KM06A

111111

30

MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSY-A15NA MSY-A17NA

3. INDOOR UNIT ELECTRICAL PARTS AND FUNCTIONAL PARTS

1

18

17

16

15

14

2

3

4

5

6

11

10

9

12

No. Part No. Part name

1 E02 751 509 BEARING MOUNT 1 1 1 1 1 1
2 E02 001 504 SLEEVE BEARING 1 1 1 1 1 1
3 E02 897 702 DRAIN HOSE 1 1 1 1 1 1

E02 A54 235

4

E02 A56 235 1 1 1 1

5 E02 897 303

6 E02 913 040 HORIZONTAL VANE 1 1 1 1 1 1

7 E02 915 095

8 E02 A49 979 CONDUIT COVER 1 1 1 1 1 1

9 E02 A49 780 TERMINAL BLOCK COVER 1 1 1 1 1 1
10 E02 A49 779 TERMINAL BLOCK HOLDER 1 1 1 1 1 1
11 E02 913 375 TERMINAL BLOCK TB 1 1 1 1 1 1

E02 A54 452
E02 A55 452 1
E02 A56 452 1

12

E02 A57 452 1
E02 A51 452 1
E02 A52 452 1

13 E02 897 308

E02 A54 307

14

E02 A56 307 1 1 1 1

15 E02 915 782 SWITCH HOLDER 1 1 1 1 1 1
16 E02 A54 300 INDOOR FAN MOTOR W2 MF 1 1 1 1 1 1 RC0J30­17 E02 897 333 MOTOR BAND 1 1 1 1 1 1
18 E02 897 302 LINE FLOW FAN 1 1 1 1 1 1

1 Including SW P.C. BOARD and POWER MONITOR RECEIVER P.C. BOARD

2 Including FAN MOTOR RUBBER MOUNT (2 PC/SET)

NOZZLE ASSEMBLY

VANE MOTOR UNIT
(HORIZONTAL)

POWER MONITOR RECEIVER
P.C. BOARD HOLDER

ELECTRONIC CONTROL P.C.
BOARD

ROOM TEMPERATURE
THERMISTOR

INDOOR COIL THERMISTOR

1

7

Symbol

in Wiring

Diagram

MV 1 1 1 1 1 1 UP & DOWN

RT11 111111

RT12,

RT13

8

Q'ty/unit

MSZ- MSY-

A09NA A12NA A15NA A17NA A15NA A17NA

11

111111

1

11

31

12

13

Remarks

□□

MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSY-A15NA MSY-A17NA

4. INDOOR UNIT HEAT EXCHANGER

1

2

3

No. Part No. Part name

E02 A54 620

1

E02 A56 620 1111
E02 815 666

2

E02 155 666 1111ø1/2

3 E02 151 667 UNION (LIQUID) 1 1 1111ø1/4

INDOOR HEAT EXCHANGER

UNION (GAS)

Symbol

in Wiring

Diagram

A09NA A12NA A15NA A17NA A15NA A17NA

11

11 ø3/8

Q'ty/unit

MSZ- MSY-

5. AIR CLEANING FILTER (ANTI-ALLERGY ENZYME FILTER)

● AIR CLEANING FILTER removes fine dust of 0.01 micron from air by means of static electricity.

● Normal life of AIR CLEANING FILTER is 1 year.

If AIR CLEANING FILTER is to be washed, soak AIR CLEANING FILTER in water (when showing dirt, in lukewarm

water) and rinse it delicately, without removing the filter from the frame about once every 3 months.

● Clogged AIR CLEANING FILTER may reduce the air conditioner capacity or cause frost on the air outlet.

● Do not remove or attach AIR CLEANING FILTER during unit operation.

Model Part No.

MSZ-A09/12/15/17NA

MSY-A15/17NA

Replacement of the air cleaning filter

(1) Remove the catechin air filter (left one).
The air cleaning filter is not attached to

the right side catechin air filter.

MAC-415FT-E

(2) Remove the air cleaning filter (Blue bel-

lows type) from the catechin air filter.

Remarks

32

Air cleaning filter
(Blue bellows type)

MSZ-A24NA
MSY-A24NA

6. INDOOR UNIT STRUCTURAL PARTS

1

2

3

7. INDOOR UNIT HEAT EXCHANGER

11

4

5

8

9
(See 10-1.10.)

12

13

6

7

6. INDOOR UNIT STRUCTURAL PARTS

Part number that is circled is not shown in the illustration.

No. Part No. Part Name

1 E02 527 970 INSTALLATION PLATE 1 1
2 E02 685 234 BOX 1 1
3 E02 888 000 FRONT PANEL ASSEMBLY 1 1 Including No.5,6
4 E02 408 142 CATCH 4 4 4 PC/SET
5 E02 685 067 SCREW CAP 3 3 3 PC/SET
6 E02 888 010 GRILLE 1 1
7 E02 534 100 CATECHIN AIR FILTER 2 2 1 PC/SET
8 E02 685 975 CORNER BOX (RIGHT) 1 1
9 -— AIR CLEANING FILTER 2 2 MAC-2300FT

10 E02 888 007 LAMP PANEL 1 1

Symbol

in Wiring

Diagram

MSZ-A24NA MSY-A24NA

Q'ty/unit

Remarks

7. INDOOR UNIT HEAT EXCHANGER

11 E02 A58 620 INDOOR HEAT EXCHANGER 1 1

12 E02 527 666 UNION (GAS) 1 1 ø5/8
13 E02 151 667 UNION (LIQUID) 1 1 ø1/4

33

MSZ-A24NA
MSY-A24NA

8. INDOOR UNIT FUNCTIONAL PARTS AND
ELECTRICAL PARTS

1

2

3

18

17

9. ACCESSORY AND
REMOTE CONTROLLER

21

22

4

10

9

16

5

6

12

11

15

8

7

15

14

13

8. INDOOR UNIT FUNCTIONAL PARTS AND ELECTRICAL PARTS

Part numbers that is circled is not shown in the illustration.

2

Symbol

in Wiring

Diagram

RT12,

RT13

MSZ-A24NA MSY-A24NA

No. Part No. Part Name

1 E02 527 302 LINE FLOW FAN 1 1
2 E02 408 509 BEARING MOUNT 1 1
3 E02 001 504 SLEEVE BEARING 1 1
4 E02 408 702 DRAIN HOSE 1 1
5 E02 A58 235 NOZZLE 1 1
6 E02 685 040 VANE UPPER 1 1
7 E02 685 041 VANE LOWER 1 1
8 E02 527 034 VANE CRANK SET 1 1

9 E02 A58 300 INDOOR FAN MOTOR ASSEMBLY
10 E02 448 303 VANE MOTOR (VERTICAL) MV2 2 2 RIGHT & LEFT
11 E02 408 303 VANE MOTOR (HORIZONTAL) MV1 1 1 UP & DOWN
12 E02 918 333 MOTOR BAND 1 1
13 E02 918 329 DISPLAY P.C. BOARD 1 1
14 E02 918 468 RECEIVER P.C. BOARD 1 1

E02 A58 452

15

E02 A53 452 1
16 E02 527 308 ROOM TEMPERATURE THERMISTOR RT11 1 1
17 E02 A58 375 TERMINAL BLOCK TB 1 1

18 E02 918 307 INDOOR COIL THERMISTOR

19 E02 528 034 VANE MOTOR SUPPORT SET(RIGHT) 1 1
20 E02 529 034 VANE MOTOR SUPPORT SET(LEFT) 1 1

1 Including FAN MOTOR RUBBER MOUNT
2 Including SW P.C. BOARD

ELECTRONIC CONTROL P.C. BOARD

1 MF 1 1 RC0J56-□□

Q'ty/unit

Remarks

1

11

9. ACCESSORY AND REMOTE CONTROLLER

E02 A58 426
21

E02 A53 426 1 KM06D
22 E02 527 083 REMOTE CONTROLLER HOLDER 1 1

REMOTE CONTROLLER

34

1 KM06B

10. AIR CLEANING FILTER (ANTI-ALLERGY ENZYME FILTER)

● AIR CLEANING FILTER removes fine dust of 0.01 micron from air by means of static electricity.

● Normal life of AIR CLEANING FILTER is 1 year.

If AIR CLEANING FILTER is to be washed, soak AIR CLEANING FILTER in water (when showing dirt, in lukewarm

water) and rinse it delicately, without removing the filter from the frame about once every 3 months.

● Clogged AIR CLEANING FILTER may reduce the air conditioner capacity or cause frost on the air outlet.

● Do not remove or attach AIR CLEANING FILTER during unit operation.

Model Part No.

MSZ-A24NA
MSY-A24NA

MAC-2300FT

Air cleaning filter
(Anti-allergy enzyme filter:blue bellows type)

35

10-2. RoHS PARTS LIST (RoHS compliant)
MSZ-A09NA MSY-A15NA
MSZ-A12NA MSY-A17NA
MSZ-A15NA
MSZ-A17NA

1. INDOOR UNIT STRUCTURAL PARTS

1

2. ACCESSORY AND REMOTE

9

CONTROLLER

10

11

12

8

2

7
(See 10-2.5.)

3

4

5

6

1. INDOOR UNIT STRUCTURAL PARTS

1

Q'ty/unit

1

-

Remarks

1

-

1

-

1

-

Including
No.3,4

Symbol

No.

1 G E12 A32 234 BOX 111111111111

2 G E12 A49 000 PANEL ASSEMBLY 111111111111

3 G E12 913 067 SCREW CAP 2222222222222 PC/SET
4 G E12 915 010 FRONT PANEL 111111111111

5 G E12 915 100

6 G E12 916 100

7G —

8 G E12 A32 975

9 G E12 913 970 INSTALLATION PLATE 111111111111

10 G E12 A49 978 CONDUIT PLATE 1 1 1 1 1 1

Part No. Part name

RoHS

CATECHIN AIR FILTER
(LEFT)
CATECHIN AIR FILTER
(RIGHT)
AIR CLEANING
FILTER
CORNER BOX
(RIGHT)

in Wiring

Diagram

09NA 12NA 15NA 17NA 15NA 17NA

-

111111111111

111111111111

111111111111MAC-415FT-E

111111111111

MSZ-A MSY-A

1

-

2. ACCESSORY AND REMOTE CONTROLLER

G E12 A54 426

G E12 A49 426 1 1 KM06C

11

G E12 C30 426 1 1 KM07L
G E12 C22 426 1 1 1 1 KM07J

12 G E12 527 083

REMOTE
CONTROLLER

REMOTE
CONTROLLER
HOLDER

1 1 1 1 KM06A

111111111111

36

MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSY-A15NA MSY-A17NA

3. INDOOR UNIT ELECTRICAL PARTS AND FUNCTIONAL PARTS

1

19

18

17

16

15

2

3

4

5

6

12

11

10

12

No.

1 G E12 751 509 BEARING MOUNT 1 1 1 1 11111111
2 G E12 001 504 SLEEVE BEARING 1 1 1 1 11111111
3 G E12 897 702 DRAIN HOSE 111111111111

4

5 G E12 897 303
6 G E12 913 040 HORIZONTAL VANE 1 1 1 111111111

7 G E12 915 095

8 G E12 A49 979 CONDUIT COVER 1 1 1 1 1 1
9 G E12 C30 979 CONDUIT COVER 1 1 1 1 1 1

10

11

12 G E12 913 375 TERMINAL BLOCK TB 1 1 1111111111

13

14 G E12 897 308

15

16 G E12 915 782 SWITCH HOLDER 1 11111111111
17 G E12 A54 300
18 G E12 897 333 MOTOR BAND 1 1 1 1 11111111
19 G E12 897 302 LINE FLOW FAN 111111111111

1 Including SW P.C. BOARD and POWER MONITOR RECEIVER P.C. BOARD
2 Including FAN MOTOR RUBBER MOUNT (2 PC/SET)

Part No. Part name

RoHS

G E12 A54 235
G E12 A56 235 1

G E12 A49 780
G E12 C30 780 1 1 1 1 1 1
G E12 A49 779
G E12 C30 779 1 1 1 1 1 1

G E12 A54 452
G E12 A55 452 1 1
G E12 A56 452 1 1
G E12 A57 452 1 1
G E12 A51 452 11
G E12 A52 452 11

G E12 A54 307
G E12 A56 307 1 1111111

NOZZLE ASSEMBLY

VANE MOTOR UNIT (HORIZONTAL)

POWER MONITOR RECEIVER
P.C. BOARD HOLDER

TERMINAL BLOCK
COVER

TERMINAL BLOCK
HOLDER

ELECTRONIC
CONTROL P.C.
BOARD

ROOM TEMPERATURE THERMISTOR
INDOOR COIL

THERMISTOR

INDOOR FAN MOTOR 2

1

8

7

Symbol

in Wiring

Diagram

MV 111111111111UP & DOWN

RT11 111111111111

RT12,

RT13

MF 111111111111RC0J30-□□

09NA 12NA 15NA 17NA 15NA 17NA

1

-

1111

111111111111

111111

111111

11

1111

13

9

MSZ-A MSY-A

1

-

14

Q'ty/unit

1

-

1111111

1

-

1

-

1

-

Remarks

37

MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSY-A15NA MSY-A17NA

4. INDOOR UNIT HEAT EXCHANGER

1

2

3

No.

1

2

Part No. Part name

RoHS

G E12 A54 620
G E12 A56 620 11111111
G E12 815 666
G E12 155 666 11111111ø1/2

INDOOR HEAT
EXCHANGER

UNION (GAS)

in Wiring

Diagram

09NA 12NA 15NA 17NA 15NA 17NA

1

-

1111

1111 ø3/8

Symbol

MSZ-A MSY-A

1

-

1

-

1

-

1

-

1

-

3 G E12 151 667 UNION (LIQUID) 111111111111ø1/4

5. AIR CLEANING FILTER (ANTI-ALLERGY ENZYME FILTER)

● AIR CLEANING FILTER removes fine dust of 0.01 micron from air by means of static electricity.

● Normal life of AIR CLEANING FILTER is 1 year.

If AIR CLEANING FILTER is to be washed, soak AIR CLEANING FILTER in water (when showing dirt, in lukewarm

water) and rinse it delicately, without removing the filter from the frame about once every 3 months.

● Clogged AIR CLEANING FILTER may reduce the air conditioner capacity or cause frost on the air outlet.

● Do not remove or attach AIR CLEANING FILTER during unit operation.

Model Part No.

Q'ty/unit

MSZ-A09/12/15/17NA

MSY-A15/17NA

Replacement of the air cleaning filter

(1) Remove the catechin air filter (left one).
The air cleaning filter is not attached to

the right side catechin air filter.

MAC-415FT-E

(2) Remove the air cleaning filter (Blue bel-

lows type) from the catechin air filter.

Remarks

38

Air cleaning filter
(Blue bellows type)

MSZ-A24NA
MSY-A24NA

6. INDOOR UNIT STRUCTURAL PARTS

1

2

3

7. INDOOR UNIT HEAT EXCHANGER

11

4

5

8

9
(See 10-2.10.)

12

13

6

7

6. INDOOR UNIT STRUCTURAL PARTS

Part number that is circled is not shown in the illustration.

No.

1 G E12 527 970 INSTALLATION PLATE 1 1 1 1
2 G E12 685 234 BOX 1 1 1 1
3 G E12 888 000 FRONT PANEL ASSEMBLY 1 1 1 1 Including No.5,6
4 G E12 408 142 CATCH 4 4 4 4 4 PC/ SET
5 G E12 685 067 SCREW CAP 3 3 3 3 3 PC/ SET
6 G E12 888 010 GRILLE 1 1 1 1
7 G E12 534 100 CATECHIN AIR FILTER 2 2 2 2 1 PC/ SET
8 G E12 685 975 CORNER BOX (RIGHT) 1 1 1 1
9 G — AIR CLEANING FILTER 2 2 2 2 MAC-2300FT

10 G E12 888 007 LAMP PANEL 1 1 1 1

Part No. Part Name

RoHS

Symbol

in Wiring

Diagram

MSZ-A24NA MSY-A24NA

Q'ty/unit

1

-

Remarks

1

-

7. INDOOR UNIT HEAT EXCHANGER

11 G E12 A58 620 INDOOR HEAT EXCHANGER 1 1 1 1
12 G E12 527 666 UNION (GAS) 1 1 1 1 ø5/8
13 G E12 151 667 UNION (LIQUID) 1 1 1 1 ø1/4

39

MSZ-A24NA
MSY-A24NA

8. INDOOR UNIT FUNCTIONAL PARTS AND
ELECTRICAL PARTS

1
2

3

18

17

9. ACCESSORY AND
REMOTE CONTROLLER

21

22

4

10

9

16

5

6

12

11

15

8

7

13 14

15

8. INDOOR UNIT FUNCTIONAL PARTS AND ELECTRICAL PARTS

Part numbers that are circled are not shown in the illustration.

No.

1 G E12 527 302 LINE FLOW FAN 1 1 1 1
2 G E12 408 509 BEARING MOUNT 1 1 1 1
3 G E12 001 504 SLEEVE BEARING 1 1 1 1
4 G E12 408 702 DRAIN HOSE 1 1 1 1
5 G E12 A58 235 NOZZLE 1 1 1 1
6 G E12 685 040 VANE UPPER 1 1 1 1
7 G E12 685 041 VANE LOWER 1 1 1 1
8 G E12 527 034 VANE CRANK SET 1 1 1 1

9 G E12 A58 300

10 G E12 448 303 VANE MOTOR (VERTICAL) MV2 2 2 2 2 RIGHT & LEFT

11 G E12 408 303 VANE MOTOR (HORIZONTAL) MV1 1 1 1 1 UP & DOWN
12 G E12 918 333 MOTOR BAND 1 1 1 1
13 G E12 918 329 DISPLAY P.C. BOARD 1 1 1 1
14 G E12 918 468 RECEIVER P.C. BOARD 1 1 1 1

15

16 G E12 527 308

17 G E12 A58 375 TERMINAL BLOCK TB 1 1 1 1
18 G E12 918 307 INDOOR COIL THERMISTOR RT12, RT13 1 1 1 1
19 G E12 528 034
20 G E12 529 034

1 Including FAN MOTOR RUBBER MOUNT
2 Including SW P.C. BOARD

Part No. Part Name

RoHS

INDOOR FAN MOTOR
ASSEMBLY

G E12 A58 452
G E12 A53 452 11

ELECTRONIC CONTROL P.C.
BOARD

ROOM TEMPERATURE
THERMISTOR

VANE MOTOR SUPPORT SET (RIGHT)
VANE MOTOR SUPPORT SET (LEFT)

1

2

Symbol

in Wiring

Diagram

MF 1 1 1 1 RC0J56-□□

RT11 1 1 1 1

MSZ-A24NA MSY-A24NA

11

1111
1111

Q'ty/unit

1

-

Remarks

1

-

9. ACCESSORY AND REMOTE CONTROLLER

G E12 A58 426
G E12 A53 426 1 KM06D

21

G E12 C26 426 1 KM07K
G E12 C29 426 1 KM07M

22 G E12 527 083

REMOTE CONTROLLER

REMOTE CONTROLLER HOLDER

40

1 KM06B

1111

10. AIR CLEANING FILTER (ANTI-ALLERGY ENZYME FILTER)

● AIR CLEANING FILTER removes fine dust of 0.01 micron from air by means of static electricity.

● Normal life of AIR CLEANING FILTER is 1 year.

If AIR CLEANING FILTER is to be washed, soak AIR CLEANING FILTER in water (when showing dirt, in lukewarm

water) and rinse it delicately, without removing the filter from the frame about once every 3 months.

● Clogged AIR CLEANING FILTER may reduce the air conditioner capacity or cause frost on the air outlet.

● Do not remove or attach AIR CLEANING FILTER during unit operation.

Model Part No.

MSZ-A24NA
MSY-A24NA

MAC-2300FT

Air cleaning filter
(Anti-allergy enzyme filter:blue bellows type)

41

11

MICROPROCESSOR CONTROL

MSZ-A09NA MSZ-A17NA MSY-A15NA
MSZ-A12NA MSZ-A24NA MSY-A17NA
MSZ-A15NA MSY-A24NA

WIRELESS REMOTE CONTROLLER

Signal transmitting section

Operation display section

ON/OFF (operate/

stop) button

Temperature buttons

Indication of
remote controller
model is on back

NOTE

Use the remote controller
provided with the unit only.
Do not use other remote
controller.

(This diagram shows an overall view.)

(This diagram shows an overall view.)

These pictures show MSZ-A24.

VANE button
(Horizontal vane button)

Operation select button

ECONO COOL button

WIDE VANE button
(V

ertical vane button)

(MSZ-A24, MSY-A24)

POWERFUL button

RESET button

(This diagram shows an overall view.)

Fan speed control button

Off-timer button

On-timer button
TIME set buttons

Forward button
Backward button

CLOCK set button

Once the operation mode is set, the same operation mode can be repeated by simply turning OPERATE/STOP
(ON/OFF) button ON.
Indoor unit receives the signal with a beep tone.
When the system turns off, 3-minute time delay will operate to protect system from overload and compressor will not

restart for 3 minutes.

INDOOR UNIT DISPLAY SECTION

Operation Indicator lamp

The operation indicator at the right side of the indoor unit indicates the operation state.

•The following indication applies regardless of shape of shape of the indication.

Indication Operation state

This shows that the air conditioner is
operating to reach the target temperature.
Please wait until the target temperature is
obtained.

This shows that the room temperature is
approaching the target temperature.

This shows a state of standby for operation.
(For multi system air conditioner)

Difference between
target temperature
and room temperature

Approx. 4°F or more

Approx. 4°F or less

—

42

Lighted

Blinking

Not lighted

11-1. COOL ( ) OPERATION

(1) Press OPERATE/STOP (ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.

(2) Select COOL mode with OPERATION SELECT button.
(3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button) to select the desired temperature.
The setting range is 61 ~ 88°F.

1. Coil frost prevention

When the temperature of indoor heat exchanger becomes too low, the coil frost prevention mode works.
The indoor fan operates at the set speed and the compressor stops. This mode continues until the temperature of indoor

heat exchanger rises.

2. Low outside temperature operation

When the outside temperature lowers during cool mode operation, low outside temperature operation starts, and the out-

door fan slows or stops.

11-2. DRY ( ) OPERATION

(1) Press OPERATE/STOP (ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select DRY mode with OPERATION SELECT button.
(3) The set temperature is determined from the initial room temperature.

1. Coil frost prevention

Coil frost prevention is as same as COOL mode. (11-1.1.)

2. Low outside temperature operation

Low outside temperature operation is as same as COOL mode. (11-1.2.)

11-3. HEAT ( ) OPERATION (MSZ)

(1) Press OPERATE/STOP (ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.

(2) Select HEAT mode with OPERATION SELECT button.
(3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button) to select the desired temperature.
The setting range is 61 ~ 88°F.

1. Cold air prevention control

When the compressor is not operating or is starting, and the temperature of indoor heat exchanger and/or the room tem­perature is low or when defrosting is being done, the indoor fan will stop or rotate in Very Low speed.

2. High pressure protection

In HEAT operation the compressor operational frequency is controlled by the temperature of the indoor heat exchanger to
prevent the condensing pressure from increasing excessively.

3. Defrosting

Defrosting starts when the temperature of outdoor heat exchanger becomes too low.
The indoor/outdoor fans stop, the 4-way valve reverses, and the compressor starts.
This mode continues until the temperature of outdoor heat exchanger rises or the fixed time passes.

11-4. FAN( )OPERATION (MSY)

(1) Press OPERATE/STOP (ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit turns ON with a beep tone.
(2) Select FAN mode with OPERATION SELECT button.
(3) Select the desired fan speed. When AUTO, it becomes Low.
Only indoor fan operates. Outdoor unit does not operate.

11-5. “I FEEL CONTROL” ( ) OPERATION (MSY)

(1) Press OPERATE/STOP (ON/OFF) button on the remote

controller. OPERATION INDICATOR lamp of the indoor
unit turns on with a beep tone.

(2) Select “I FEEL CONTROL” mode with OPERATION

SELECT button.

(3) The operation mode is determined by the room tempera-

ture at start-up of the operation.

• Once the mode is fixed, the mode does not change by room temperature afterwards.

• Under the ON-TIMER (
operation starts.

) operation, mode is determined according to the room temperature at the set time the

43

Initial room temperature Mode

75 °F or more

less than 75 °F

COOL mode of

"I FEEL CONTROL"

DRY mode of

"I FEEL CONTROL"

(4) The initial set temperature is decided by the initial room temperature.

Model Initial room temperature Initial set temperature

COOL mode of

79 °F or more 75°F

"I FEEL CONTROL"

77 °F to 79 °F Initial room temperature minus 4 °F

DRY mode of

"I FEEL CONTROL"

less than 77 °F Initial room temperature minus 4 °F

1 When the system is restarted with the remote controller, the system operates with the previous set temperature regard-

less of room temperature at restart.

The set temperature is calculated by the previous set temperature.

(5) TEMPERATURE buttons

In “I FEEL CONTROL” (

) mode, set temperature is decided by the microprocessor based on the room temperature.

In addition, set temperature can be controlled by TOO WARM or TOO COOL buttons when you feel too cool or too warm.
Each time the TOO WARM or TOO COOL button is pressed, the indoor unit receives the signal and emits a beep tone.

• Fuzzy control

When the TOO COOL or TOO WARM button is pressed, the microprocessor changes the set temperature, considering
the room temperature, the frequency of pressing TOO COOL or TOO WARM button and the user’s preference to heat or
cool. So this is called “Fuzzy control”, and works only in “I FEEL CONTROL” mode.
In DRY mode of “I FEEL CONTROL”, the set temperature doesn’t change.

TOO

COOL

…To raise the set temperature 2~4 °F

TOO

WARM

…To lower the set temperature 2~4 °F

1

11-6. AUTO CHANGE OVER ··· AUTO MODE OPERATION (MSZ)

Once desired temperature is set, unit operation is switched automatically between COOL and HEAT operation.

Mode selection

(1) Initial mode

When unit starts the operation with AUTO operation from off;

• If the room temperature is higher than the set temperature, operation starts in COOL mode.

• If the room temperature is equal to or lower than the set temperature, operation starts in HEAT mode.

(2) Mode change

COOL mode changes to HEAT mode when about 15 minutes have passed with the room temperature 4°F below the set
temperature.
HEAT mode changes to COOL mode when about 15 minutes have passed with the room temperature 4°F above the set
temperature.

NOTE:

If two or more indoor units are operating in multi system, there might be a case that the indoor unit, which is operating in
(AUTO), cannot change over to the other operating mode (COOL ↔ HEAT) and becomes a state of standby.
Refer to 8-1. ”INFORMATION FOR MULTI SYSTEM AIR CONDITIONER”.

44

11-7. AUTO VANE OPERATION

1. Horizontal vane

(1) Vane motor drive
These models are equipped with a stepping motor for the horizontal vane. The rotating direction, speed, and angle of

the motor are controlled by pulse signals (approx. 12 V) transmitted from indoor microprocessor.

(2) The horizontal vane angle and mode change as follows by pressing VANE CONTROL button.

MSZ-A09/12/15/17
MSY-A15/17

MSZ-A24
MSY-A24

(3) Positioning
The vane is once pressed to the vane stopper to confirm the standard position and then set to the desired angle.
Confirming of standard position is performed in the following cases.
(a) When the operation starts or finishes (including timer operation).
(b) When the test run starts.
(c) When multi-standby starts or finishes.

(4) VANE AUTO (

In VANE AUTO mode, the microprocessor automatically determines the vane angle and operation to make the optimum
room-temperature distribution.

) mode

(1) COOL and DRY operation
Vane angle is fixed to Horizontal position or Angle 1.

Upward

(5) STOP (operation OFF) and ON-TIMER standby

In the following cases, the horizontal vane returns to the closed position.
(a) When OPERATE/STOP (ON/OFF) button is pressed (POWER OFF).
(b) When the operation is stopped by the emergency operation.
(c) When ON-TIMER is ON standby.

(6) Dew prevention

During COOL or DRY operation with the vane angle at Angle 2 ~ 4 (A09 ~ 17) / Angle 3 ~ 5 (A24) when the compressor
cumulative operation time exceeds 1 hour, the vane angle automatically changes to Angle 1 for dew prevention.

(7) SWING MODE (

By selecting SWING mode with VANE CONTROL button, the horizontal vane swings vertically. The remote controller
displays “ ”.

(8) Cold air prevention in HEAT operation (MSZ)

The horizontal vane position is set to Upward.

NOTE : When 2 or more indoor units are operated with multi outdoor unit, even if any indoor unit turns thermostat off,

this control doesn’t work in the indoor unit.

)

(2) HEAT operation (MSZ)
Vane angle is fixed to Angle 4.

45

(9) To change the airfl ow direction not to blow directly onto your body. (MSZ-A09/12/15/17, MSY-A15/17)

To change the airfl ow direc-

tion

Pressing and holding VANE
CONTROL button for 2
seconds or more cause the
horizontal vane to reverse
and move to horizontal posi­tion.

Horizontal

position

When to use this function? COOL/DRY

Use this function if you don’
t want the air from the indoor
unit to blow directly onto your
body.

• Depending on the shape of
the room, the air may blow
directly onto your body.

The air conditioner starts
the cooling or drying opera­tion approx. 3 minutes after
the vane has moved to the
horizontal position.

• When VANE CONTROL
button is pressed again,
the vane returns to the

• Press VANE CONTROL
button again to return the
vane to the previously-set
position.

previously-set position and
the air conditioner starts
the cool or dry operation in
approx. 3 minutes.

The air conditioner starts heating
operation approx. 3 minutes after
the vane has moved to the horizon­tal position.

• Sometimes the area around your
feet may not warm. To warm the
area around the feet, set the hori­zontal vane to
downward-blowing position.

• When VANE CONTROL button is
pressed again, the vane returns

HEAT

(For MSZ)

(AUTO) or the

to the previously-set position and
the air conditioner starts the heat
operation in approx. 3 minutes.

NOTE :

• If you make the airfl ow not to blow directly onto your body by pressing VANE CONTROL button, the compressor stops for 3

minutes even during the operation of the air conditioner.

• The air conditioner operates with Very Low speed until the compressor turns on again.

(10) ECONO COOL ( ) operation (ECONOmical operation)

When ECONO COOL button is pressed in COOL mode, set temperature is automatically set 3.6°F higher than that in
COOL mode.
Also the horizontal vane swings in various cycle.
SWING operation makes you feel cooler than set temperature. So, even though the set temperature is higher than that
in COOL mode, the air conditioner can keep comfort. As a result, energy can be saved.
ECONO COOL operation is cancelled when ECONO COOL button is pressed once again or VANE CONTROL button is
pressed or change to other operation mode.

(11) POWERFUL ( ) operation

The air conditioner automatically adjusts the fan speed and the set temperature, and operates the POWERFUL mode.
The POWERFUL mode is automatically released 15 minutes after operation starts, and the operation mode returns to
the mode prior to POWERFUL operation.

2. Vertical vane (MSZ-A24, MSY-A24)

(1) Vane motor drive
These models are equipped with a stepping motor for the vertical vane. The rotating direction, speed, and angle of the

motor are controlled by pulse signals (approx. 12 V) transmitted from microprocessor.

(2) The vertical vane angle and mode change as follows by pressing WIDE VANE button.

23

45SWING

61

(3) Positioning
The vane is once pressed to the vane stopper to confirm the standard position and then set to the desired angle.
Confirming of standard position is performed in the following cases.
(a) When OPERATE/STOP (ON/OFF) button is pressed (POWER ON/OFF).
(b) When SWING is started or finished.
(c) When the power supply turns ON.
(4) SWING MODE (

)
By selecting SWING mode with WIDE VANE button, the vertical vane swings horizontally.
The remote controller displays “ ”.

46

(5) WIDE MODE ( )
By selecting WIDE mode with WIDE VANE button, indoor fan speed becomes faster than setting fan speed on the

remote controller (

NOTE : The position of vane angle 3, angle 4 and angle 5 are different in COOL operation and HEAT operation.

selected.

). The remote controller displays “ ”.

Indoor fan speed becomes faster than setting fan speed on the remote controller even when or is

11-8. TIMER OPERATION

1. How to set the time

(1) Press OPERATE/STOP (ON/OFF) button to start the air conditioner.
(2) Check that the current time is set correctly.
NOTE : Timer operation will not work without setting the current time. Initially “0:00” blinks at the current time display of

TIME MONITOR, so set the current time correctly with CLOCK SET button.

How to set the current time

(1) Press the CLOCK set button.
(2) Press the TIME SET buttons (

• Each time FORWARD button (
(

• Pressing those buttons longer increases / decreases the set time by 10 minutes.
Press the CLOCK set button.

ON timer setting

(1) Press ON-TIMER button(
(2) Set the time of the timer using TIME SET buttons ( and ) .

OFF timer setting

(1) Press OFF-TIMER button (
(2) Set the time of the timer using TIME SET buttons (

Each time FORWARD button ( ) is pressed, the set time increases by 10 minutes; each time BACKWARD button
( ) is pressed, the set time decreases by 10 minutes.

2. Cancel

) is press, the set time decreases by 1 minute.

To cancel ON timer, press ON-TIMER button (
To cancel OFF timer, press OFF-TIMER button( ).
TIMER is cancelled and the display of set time disappears.

and ) to set the current time.

) is press, the set time increases by 1 minute, and each time BACKWARD button

) during operation.

) during operation.

and ).

).

PROGRAM TIMER

• OFF timer and ON timer can be used in combination. The timer of the set time that is reached first will operate first.

• “ ” and “ ” display shows the order of OFF timer and ON timer operation.

(Example 1) The current time is 8:00 PM.

The unit turns off at 11:00 PM, and on at 6:00 AM.

NOTE : If the main power is turned off or a power failure occurs while AUTO START/STOP timer is active, the timer set-

ting is cancelled. As these models are equipped with an auto restart function, the air conditioner starts operating
with timer cancelled when power is restored.

(Example 2) The current time is 11:00 AM.

The unit turns on at 5:00 PM, and off at 9:00 PM.

47

11-9. EMERGENCY/TEST OPERATION

In case of test run operation or emergency operation, use EMERGENCY OPERATION switch on the front of the indoor
unit. Emergency operation is available when the remote controller is missing, has failed or the batteries of the remote
controller run down. The unit will start and OPERATION INDICATOR lamp will light.
The first 30 minutes of operation is the test run operation. This operation is for servicing. The Indoor fan speed runs at
High speed and the system is in continuous operation (with thermostat ON).
After 30 minutes of test run operation the system shifts to EMERGENCY COOL/HEAT MODE with a set temperature of 75°F.
The fan speed shifts to Med.
All protective operations such as the coil frost prevention works even in emergency operation.
In the test run or emergency operation, the horizontal vane operates in VANE AUTO (
Emergency operation continues until EMERGENCY OPERATION switch is pressed once or twice or the unit receives any
signal from the remote controller. In case of latter normal operation will start.

NOTE : Do not press EMERGENCY OPERATION switch during normal operation.

Operation mode COOL HEAT (MSZ)

Set temperature 75°F 75°F

Fan speed Med. Med.

E.O.

SW

EMERGENCY OPERATION switch

Horizontal vane Auto Auto

The operation mode is indicated by the Operation
Indicator lamp as following

MSZ type

EMERGENCY

COOL

EMERGENCY

HEAT

STOP

MSY type

EMERGENCY

COOL

STOP

↓

↓

↓

) mode.

Lighted

Not lighted

11-10. Changing temperature indication (°F/°C)

MSZ-A•NA-
MSY-A•NA-

The preset unit is °F.
Press RESET button while
the temperature buttons
are pressed.

Copyright 2006 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD
Distributed in Jun. 2008. No. OB450 REVISED EDITION-C 6
Distributed in May 2007. No. OB450 REVISED EDITION-B 7
Distributed in Dec. 2006. No. OB450 REVISED EDITION-A 7
Distributed in Apr. 2006. No. OB450 7
Made in Japan

1
1

Press RESET button gently
using a thin stick.

HEAD OFFICE: TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN

New publication, effective Jun. 2008
Specifications subject to change without notice.