Mitsubishi PLA-A36AA, PLA-A30AA, PLA-A24AA, PLA-A12AA User Manual

SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS

ON/OFF TEMP

ON/OFF

TEMP.

SPLIT-TYPE, AIR CONDITIONERS

SERVICE MANUAL

Indoor unit
[Model names] [Service Ref.]

PLA-A12AA

PLA-A12AA PLA-A12AA1

June 2007

No. OC370

REVISED EDITION-B

Revision:

• WIRING DIAGRAM has been
changed in REVISED EDI­TION-B.

• Some descriptions have been
modified.

PLA-A18AA

PLA-A24AA

PLA-A30AA

PLA-A36AA

PLA-A42AA

Model name
indication

PLA-A18AA PLA-A18AA1
PLA-A24AA PLA-A24AA1
PLA-A30AA PLA-A30AA1
PLA-A36AA PLA-A36AA1
PLA-A42AA PLA-A42AA1

CONTENTS

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

2. REFERENCE MANUAL······································2

3. SAFETY PRECAUTION···································3

4. PART NAMES AND FUNCTIONS ···················5

5. SPECIFICATIONS············································8

6. NOISE CRITERION CURVES························10

7. OUTLINES AND DIMENSIONS·····················11

8.

WIRING DIAGRAM

INDOOR UNIT

9.

REFRIGERANT SYSTEM DIAGRAM

10. TROUBLESHOOTING ···································14

11. DISASSEMBLY PROCEDURE ·······················30

12. PARTS LIST···················································33

13. RoHS PARTS LIST ········································38

• Please void OC370 REVISED
EDITION-A.

NOTE:

• This manual describes only
service data of the indoor
units.

• RoHS compliant products
have <G> mark on the spec
name plate.

• For servicing RoHS compliant
products, refer to the RoHS
PARTS LIST.

············································12

··················13

WIRELESS REMOTE

CONTROLLER

WIRED REMOTE

CONTROLLER

3 3 2 2 3

1

Series (Outdoor unit)

PUZ-A·NHA(-BS)
PUY-A·NHA(-BS)

Manual No.

OCS04

TECHNICAL CHANGES

PLA-A12AA ➔ PLA-A12AA1

PLA-A18AA ➔ PLA-A18AA1
PLA-A24AA ➔ PLA-A24AA1
PLA-A30AA ➔ PLA-A30AA1
PLA-A36AA ➔ PLA-A36AA1
PLA-A42AA ➔ PLA-A42AA1

• Indoor controller board has been changed.

2

REFERENCE MANUAL

2-1. OUTDOOR UNIT SERVICE MANUAL

Service Ref.

PUZ-A18/24/30/36/42NHA
PUZ-A18/24/30/36/42NHA-BS
PUY-A12/18/24/30/36/42NHA
PUY-A12/18/24/30/36/42NHA

(1)
(1)

-BS

2-2. TECHNICAL DATA BOOK

Service Manual No.

OC367

2

3

Use new refrigerant pipes.

Make sure that the inside and outside of refrige­rant piping is clean and it has no contamination
such as sulfur hazardous for use, oxides, dirt,
shaving particles, etc.
In addition, use pipes with specified thickness.

Store the piping to be used during installation
indoors and keep both ends of the piping sealed
until just before brazing. (Leave elbow joints, etc.
in their packaging.)

Use ester oil, ether oil or alkylbenzene oil (small
amount) as the refrigerant oil applied to flares
and flange connections.

Charge refrigerant from liquid phase of gas
cylinder.

If the refrigerant is charged from gas phase, composition
change may occur in refrigerant and the efficiency will be
lowered.

Do not use refrigerant other than R410A.

If other refrigerant (R22 etc.) is used, chlorine in refrige­rant can cause deterioration of refrigerant oil etc.

Use a vacuum pump with a reverse flow check
valve.

Vacuum pump oil may flow back into refrigerant cycle and
that can cause deterioration of refrigerant oil etc.

Use the following tools specifically designed for
use with R410A refrigerant.

The following tools are necessary to use R410A refrigerant.

Keep the tools with care.

If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com­pressor.

Do not use a charging cylinder.

If a charging cylinder is used, the composition of refrigera­nt will change and the efficiency will be lowered.

Flare tool

Electronic refrigerant
charging scale

Vacuum pump adaptor

Size adjustment gauge

Gauge manifold

Torque wrench

Gas leak detector

Charge hose

Tools for R410A

Contamination inside refrigerant piping can cause deterio­ration of refrigerant oil etc.

If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com­pressor.

If large amount of mineral oil enters, that can cause deterio

-

ration of refrigerant oil etc.

Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.

SAFETY PRECAUTION

3-1. ALWAYS OBSERVE FOR SAFETY

Before obtaining access to terminals, all supply
circuits must be disconnected.

3-2. CAUTIONS RELATED TO NEW REFRIGERANT

Cautions for units utilising refrigerant R410A

[1] Cautions for service

(1) Perform service after collecting the refrigerant left in the unit completely.
(2) Do not release refrigerant in the air.
(3) After completing service, charge the cycle with specified amount of refrigerant.
(4) When performing service, install a filter drier simultaneously.

Be sure to use a filter drier for new refrigerant.

3

Gravimeter

Unit

[2] Additional refrigerant charge

When charging directly from cylinder

· Check that cylinder for R410A on the market is syphon type.

· Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)

[3] Service tools

Use the below service tools as exclusive tools for R410A refrigerant.

No. Specifications

1 Gauge manifold ·Only for R410A

·Use the existing fitting

·Use high-tension side pressure of 5.3MPa·G or over.

2 Charge hose ·Only for R410A

·Use pressure performance of 5.09MPa·G or over.

3 Electronic scale
4 Gas leak detector ·Use the detector for R134a, R407C or R410A.
5 Adaptor for reverse flow check ·Attach on vacuum pump.
6 Refrigerant charge base
7 Refrigerant cylinder ·Only for R410A Top of cylinder (Pink)

8 Refrigerant recovery equipment

specifications

Cylinder with syphon

. (UNF1/2)

4

4

Auto Air Swing Vane
Disperses airflow up and
down and adjusts the angle
of airflow direction.

Grille

Filter
Removes dust and pollutants
from intake air.

Horizontal Air Outlet
Sets horizontal airflow automatically
during cooling or dehumidifying.

Air Intake
Intakes air from room.

Operation Section

Temperature setting buttons

Down
Up

Timer Menu button
(Monitor/Set button)

Mode button (Return button)

Set Time buttons

Back

Ahead

Timer On/Off button
(Set Day button)

Opening the
lid

ON/OFF button

Fan Speed button

Filter button
(<Enter> button)

Test Run button

Check button (Clear button)

Airflow Up/Down button

Louver button
( Operation button)

T o return operation
number

Ventilation button
( Operation button)

To go to next operation
number

Built-in temperature sensor

PART NAMES AND FUNCTIONS

● Indoor Unit

● Wired remote controller

TEMP.

MENU

MONITOR/SET

BACK DAY

PAR-21MAA

ON/OFF

ON/OFF

CLOCK

OPERATION

5

FILTER

CHECK

CLEAR

TEST

● Wired remote controller

●

●

˚F˚C

˚F˚C

ERROR CODE

AFTER

TIMER

TIME SUN MON TUE WED THU FRI SAT

ON
OFF

Hr
AFTER

FILTER

FUNCTION

ONLY1Hr.

WEEKLY

SIMPLE

AUTO OFF

Note:

“PLEASE WAIT” message
This message is displayed for approximately 3 minutes when power is supplied to the indoor unit or when the unit is recovering from a power failure.
“NOT A V AILABLE” message
This message is displayed if an invalid button is pressed (to operate a function that the indoor unit does not have).
If a single remote controller is used to operate multiple indoor units simultaneously that are different types, this message will not be displayed as
far as any of the indoor units is equipped with the function.

Display Section

For purposes of this explanation,
all parts of the display are shown
as lit. During actual operation, only
the relevant items will be lit.

Identifies the current operation

Shows the operating mode, etc.
*Multilanguage display is available.

“Centrally Controlled” indicator

Indicates that operation from the
remote controller has been prohib­ited by a master controller.

“Timer is Off” indicator

Indicates that the timer is off.

Temperature Setting

Shows the target temperature.

Day-of-Week

Shows the current day of the week.

Time/Timer Display

Shows the current time, unless the simple or Auto Off
timer is set.
If the simple or Auto Off timer is set, the time to be
switched off is shown.

“Sensor” indication

Displayed when the remote controller
sensor is used.

“Locked” indicator

Indicates that remote controller but­tons have been locked.

“Clean The Filter” indicator

To be displayed on when it is time to
clean the filter.

Timer indicators

The indicator comes on if the corre­sponding timer is set.

Up/Down Air Direction indica­tor

Shows the direction of the
outcoming airflow.

“One Hour Only” indicator

Room Temperature display

Shows the room temperature. The room
temperature display range is 46–102°F.
The display blinks if the temperature
is less than 46

°

F

or 102°F

or more.

Louver display

Indicates the action of the swing louver.
Does not appear if the louver is not
running.

(Power On indicator)

Indicates that the power is on.

Fan Speed indicator

Shows the selected fan speed.

Ventilation indicator

Appears when the unit is running in
Ventilation mode.

Displayed if the airflow is set to
Low or downward during COOL
or DRY mode. (Operation varies
according to model.)
The indicator goes off in one hour,
at which time the airflow direction
also changes.

6

ON/OFF TEMP

FAN

VANE

TEST RUN

AUTO STOP

AUTO START

h

min

LOUVER

MODE

CHECK

RESETSET CLOCK

MODEL

SELECT

NOT AVAILABLE

SWING

CHECK

FAN

TEST

RUN

˚F
˚C

AMPMSTOP

START

AMPM

COOL

DRY

AUTO

FAN

HEAT

VANE CONTROL button

Changes the air flow direction.

CLOCK button

RESET button

SET button

ON/OFF button

The unit is turned ON and OFF alternately
each time the button is pressed.

LOUVER button

Changes left / right airflow direction.
(Not available for this model.)

MODE SELECT button

Switches the operation mode between
COOLING/DRY/FAN/HEATING and AUTO
mode.

wIn case the outdoor unit is cooling only
type, the heating and auto mode are not

available.

CHECK-TEST RUN button

Performs an inspection check or test opera­tion.
Do not use it for normal operation.

FAN SPEED SELECT button

Changes the fan speed.

TIMER display

Displays when in timer operation or when
setting timer.

button

Sets any desired room temperature.

CLOCK display

Displays the current time.

“ ” “ ” display

Displays the order of timer operation.

“ ” “ ” display

Displays whether timer is on or off.

Buttons used to set the “hour and minute” of
the current time and timer settings.

"h" and "min" buttons

Temperature setting display

indicates the desired temperature setting
which is set.

display

Displays selected fan speed.

display

The vertical direction of air flow is indicated.

display

Blinks when model is selected.

display

Lights up while the signal is transmitted to
the indoor unit when the button is pressed.

display

Indicate that the unit is being checked or
test-run.

OPERATION MODE display

OPERATION MODE display
Indicates which operation mode is in effect.

TIMER CONTROL buttons

AUTO STOP (OFF timer): when this switch
is set, the air conditioner will be au­tomatically stopped at the preset time.
AUTO START (ON timer): when this switch
is set, the air conditioner will be automatical­ly started at the preset time.

MODEL SELECT

CHECK

TEST RUN

● Wireless remote controller

7

Single phase,60Hz, 208/230V

15

1

Munsell 0.70Y 8.59/0.97

Plate fin coil

Turbo fan (direct) o 1

0.070

0.79
Dry: 15-16-18-20(530-570-640-710)
Wet:14-15-17-19(490-530-600-670)

0(direct blow)

–

Remote controller & built-in

28-30-32-34

32 (1-1/4)

PLA-A18AA/ PLA-A18AA

1

UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT

: 840 (33-1/16)

PANEL : 950 (37-3/8)

UNIT

: 258 (10-3/16)

PANEL : 30 (1-3/16)

UNIT

: 24 (53)

PANEL: 5 (11)

A
A

kW

F.L.A.

K/min(CFM)

Pa(mmAq)

kW

dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)

kg(lbs)

Service Ref.

Power supply (phase, cycle, voltage)

Max. Fuse Size

Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) o No.

Fan motor output

Fan motor

Airflow (Low-Medium2-Medium1-High)

External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions

Weight

W

D
H

INDOOR UNIT

Single phase,60Hz, 208/230V

15

1

Munsell 0.70Y 8.59/0.97

Plate fin coil

Turbo fan (direct) o 1

0.070

0.79

Dry: 11-12-13-14(390-420-460-490)

Wet: 10-11-12-13(350-380-420-450)

0(direct blow)

–

Remote controller & built-in

27-28-29-31

32 (1-1/4)

A
A

kW

F.L.A.

K/min(CFM)

Pa(mmAq)

kW

dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)

kg(lbs)

Service Ref.

Power supply (phase, cycle, voltage)

Max. Fuse Size

Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) o No.

Fan motor output

Fan motor

Airflow (Low-Medium2-Medium1-High)

External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions

Weight

W
D
H

INDOOR UNIT

PLA-A12AA/ PLA-A12AA1

UNIT : 840 (33-1/16)

PANEL : 950 (37-3/8)

UNIT : 840 (33-1/16)

PANEL : 950 (37-3/8)

UNIT : 258 (10-3/16)

PANEL : 30 (1-3/16)

UNIT : 22 (49)

PANEL: 5 (11)

5

PLA-A24AA/ PLA-A24AA1

UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 258 (10-3/16) PANEL : 30 (1-3/16)

UNIT : 24 (53) PANEL: 5 (11)

Single phase,60Hz, 208/230V

15

1

Munsell 0.70Y 8.59/0.97

Plate fin coil

Turbo fan (direct) o 1

0.070

0.79

Dry: 15-16-18-20(530-570-640-710)

Wet: 14-15-17-19(490-530-600-670)

0(direct blow)

–

Remote controller & built-in

28-30-32-34

32(1-1/4)

A
A

kW

F.L.A.

K/min(CFM)

Pa(mmAq)

kW

dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)

kg(lbs)

Service Ref.

Power supply (phase, cycle, voltage)

Max. Fuse Size

Min. Circuit Ampacity
External finish (Panel)
Heat exchanger
Fan Fan (drive) o No.

Fan motor output

Fan motor

Airflow (Low-Medium2-Medium1-High)

External static pressure
Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions

Weight

W

D
H

INDOOR UNIT

SPECIFICATIONS

8

Service Ref.

Power supply (phase, cycle, voltage)

External finish (Panel)
Heat exchanger
Fan Fan (drive) o No.

INDOOR UNIT

Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions

Weight

Max. Fuse Size
Min. Circuit Ampacity

Fan motor output
Fan motor

Airflow (Low-Medium2-Medium1-High)
External static pressure

W

D
H

A
A

kW

F.L.A.

K/min(CFM)

Pa(mmAq)

kW

dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)

kg(lbs)

PLA-A30AA/ PLA-A30AA1

Single phase,60Hz, 208/230V

15

1

Munsell 0.70Y 8.59/0.97

Plate fin coil

Turbo fan (direct) o 1

0.070

0.79

Dry: 15-16-18-20(530-570-640-710)

Wet: 14-15-17-19(490-530-600-670)

0(direct blow)

–

Remote controller & built-in

28-30-32-34

32(1-1/4)

UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 258 (10-3/16) PANEL : 30 (1-3/16)

UNIT : 24 (53) PANEL: 5 (11)

Service Ref.

Power supply (phase, cycle, voltage)

External finish (Panel)
Heat exchanger
Fan Fan (drive) o No.

INDOOR UNIT

Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions

Weight

Service Ref.

Power supply (phase, cycle, voltage)

External finish (Panel)
Heat exchanger
Fan Fan (drive) o No.

INDOOR UNIT

Booster heater
Operation control & Thermostat
Noise level (Low-Medium2-Medium1-High)
Field drain pipe O.D.
Dimensions

Weight

Max. Fuse Size
Min. Circuit Ampacity

Fan motor output
Fan motor

Airflow (Low-Medium2-Medium1-High)
External static pressure

W

D
H

Max. Fuse Size
Min. Circuit Ampacity

Fan motor output
Fan motor

Airflow (Low-Medium2-Medium1-High)
External static pressure

W
D
H

A
A

kW

F.L.A.

K/min(CFM)

Pa(mmAq)

kW

dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)

kg(lbs)

A
A

kW

F.L.A.

K/min(CFM)

Pa(mmAq)

kW

dB
mm(in.)
mm(in.)
mm(in.)
mm(in.)

kg(lbs)

PLA-A36AA/ PLA-A36AA

Single phase,60Hz, 208/230V

Munsell 0.70Y 8.59/0.97

Turbo fan (direct) o 1

Dry: 20-23-26-28(710-810-920-990)

Wet: 19-22-25-27(670-770-880-950)

Remote controller & built-in

UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)

UNIT : 298 (11-3/4) PANEL : 30 (1-3/16)

UNIT : 30 (66) PANEL : 5 (11)

PLA-A42AA/ PLA-A42AA

Single phase,60Hz, 208/230V

Munsell 0.70Y 8.59/0.97

Turbo fan (direct) o 1

Dry: 20-23-26-28(710-810-920-990)
Wet: 19-22-25-27(670-770-880-950)

Remote controller & built-in

UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)
UNIT : 840 (33-1/16) PANEL : 950 (37-3/8)

UNIT : 298 (11-3/4) PANEL : 30 (1-3/16)

UNIT : 30 (66)

15

2

Plate fin coil

0.110

1.25

0(direct blow)

–

33-36-39-41

32(1-1/4)

15

2

Plate fin coil

0.110

1.25

0(direct blow)

–

33-36-39-41

32(1-1/4)

P

1

1

ANEL : 5 (11)

9

6

PLA-A12AA
PLA-A12AA

1

NOTCH SPL(dB) LINE

High
Medium1
Medium2

Low

31
29
28
27

90

80

70

60

50

40

30

20

10

63 125 250 500 1000 2000 4000 8000

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

NC-60

NC-50

NC-40

NC-30

NC-20

NC-70

OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)

BAND CENTER FREQUENCIES, Hz

PLA-A36AA
PLA-A42AA
PLA-A36AA

1

PLA-A42AA1

NOTCH SPL(dB) LINE

41
39
36
33

90

80

70

60

50

40

30

20

10

63 125 250 500 1000 2000 4000 8000

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

NC-60

NC-50

NC-40

NC-30

NC-20

NC-70

BAND CENTER FREQUENCIES, Hz

High
Medium1
Medium2

Low

OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)

PLA-A18AA PLA-A18AA

1

PLA-A24AA PLA-A24AA

1

PLA-A30AA PLA-A30AA

1

NOTCH SPL(dB) LINE

34
32
30
28

90

80

70

60

50

40

30

20

10

63 125 250 500 1000 2000 4000 8000

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

NC-60

NC-50

NC-40

NC-30

NC-20

NC-70

BAND CENTER FREQUENCIES, Hz

High
Medium1
Medium2

Low

OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)

UNIT

5 ft

MICROPHONE

CEILING

NOISE CRITERION CURVES

10

7

1-1/2(37)

14-23/32(374)

11/16 (17 )

2-3/8(60)

11-1/4(286)

1-31/32~2-3/4

4-1/8(105)

B

A

7-15/32(190)

D

3-5/16
(84)

3-5/32
(80)

5/8F

3/8F

24/30/36/4212/18

1 Liquid pipe

1/2F

1/4F

MODEL

2 Gas pipe

PLA-A42AA(1)

PLA-A36AA(1)

9-1/2
(241)

10-3/16

(258)

Models

PLA-A12/18/24/30AA(1)

3-1/2
(89)

(298)

(281)

A

B

11-1/16

11-3/4

C

(20~45)

(20~45)

(50~70)

2-[1-1/16(27)

3-[1/8([2.8)

Fresh air intake

Suspension bolt pitch

Ceiling hole

Feeding hole
(Drain pump)

Drain pipe
O.D.[1-1/4([32) connection
(VP-25)

25/32~1-25/32(20~45)

25/32~1-25/32(20~45)

33-27/32~35-13/16(860~910)

D

C

[5-29/32([150)

14-[1/8([2.8)

[6-7/8([175)

[4-29/32([125)

[3-15/16([100)

31-7/8(810)

33-27/32~35-13/16(860~910)

25/32~1-25/3225/32~1-25/32

6-1/4(159)

Grille

33-1/16(840)

7-3/4(197)

2(51)

3-1/32(77)

2

1

14-23/32(374)

2-3/8(60)

11-1/4(286)

4-1/8(105)

B

A

7-15/32(190)

Ceiling hole

Feeding hole
(Drain pump)

Drain pipe
(VP-25)

D

31-7/8(810)

6-1/4(159)

Grille

33-1/16(840)

7-3/4(197)

2

1

+5

0

0

14-23/32(374)

2-3/8(60)

11-1/4(286)

4-1/8(105)

B

A

7-15/32(190)

High efficiency filter
& Fresh air intake casement(option)

Feeding hole
(Drain pump)

Drain pipe
(VP-25)

D

31-7/8(810)

6-1/4(159)

Grille

33-1/16(840)

7-3/4(197)

2

1

14-23/32(374)

2-3/8(60)

11-1/4(286)

4-1/8(105)

B

A

7-15/32(190)

Feeding hole
(Drain pump)

Ceiling surface

Drain pipe
(VP-25)

D

31-7/8(810)

6-1/4(159)

Grille

33-1/16(840)

7-3/4(197)

2

1

+5

0

+3/16

0

11/16 (17 )

+3/16 0+3/16 0+3/16 0+3/16

0

+3/16

9-3/4(248)

1-3/4(45)

14-23/32(374)

5-5/16(135)

2-3/8(60)

11-1/4(286)

4-1/8(105)

1-3/16(30)

B

A

7-15/32(190)

Unit : inch(mm)

Wiring entrance holes

(Cut out hole)

Detail drawing of fresh air intake

(Cut out hole)

Burring hole

Ceiling surface

Branch duct hole

Branch duct hole

Branch duct hole

Suspension bolt pitch

Ceiling hole

Terminal block

Suspension bolt

lower edge

Feeding hole
(Drain pump)

Drain pipe
(VP-25)

Suspension bolt
W3/8(M10)

Drain hole

Vane motor

M

M

M

M

Air intake hole

Air outlet hole

Air outlet hole

6-1/4(159)

6-1/4(159)

1(26)

23-13/16(605)

33-1/16(840)

D

3-27/32(98)

7-9/16(192)

6-3/32(155)

6-9/16(167)

3-15/16(100)

5-1/8(130)

3-17/32(90)

3-15/16(100) 3-15/16(100)

3-17/32(90)

13-25/32(350)

Burring hole

6-7/32(158)

Auto vane

31-7/8(810)

6-1/4(159)

6-1/4(159)

Air intake hole

Grille

33-1/16(840)

7-3/4(197)

37-3/8(950)

37-3/8(950)

22-23/32(577)

16-3/16(411)

16-3/16(411)

6-11/16(170)

5-1/2(140)

Air intake grille

3-1/32(77)

2(51)

22-23/32(577)

2

1

INDOOR UNIT
PLA-A12AA PLA-A18AA PLA-A24AA
PLA-A30AA PLA-A36AA PLA-A42AA

OUTLINES AND DIMENSIONS

PLA-A12AA1 PLA-A18AA1 PLA-A24AA1
PLA-A30AA1 PLA-A36AA1 PLA-A42AA1

Unit : inch(mm)

11

8

I.B

SWE
ON
OFF

SW2 SW1

Refer to tables 1 and 2
for service PCB.

HEATER
CN24

(

YLW

)

D.SENSOR
CN31

(

WHT

)

1 2 3

INTAKE

CN20

(

RED

)

1 2

LIQUID

CN21

(

WHT

)

PIPE

CN29

(

BLK

)

1 2

1 2

REMOCON
CN22

(

BLU

)

1 2

TH5

TH1

DS

TH2

2

1

TB5

R.B

TB6

12

TRANSMISSION WIRES DC12V

LED3 LED2 LED1

CN41 CN2L

CN51

CN32

WIRELESS
CN90

(

WHT

)

VANE
CN6V

(

GRN

)

W.B

BZ

CNB

RU

LED2 LED1

SW2SW1

9

5

5

1 31 2

BLK

BLU

BLU

WHT

BRN

ORN

POWER
CN2D
(WHT)

A-CONTROL
CN3C
(BLU)

1 31 31 31 3

ZNR

FUSE

WHT

RED

YLW

YLW

YLW

YLW

YLW

ORN

POWER

CNDK
(RED)

POWER

CND

(ORN)

D.U.M

CNP

(BLU)

DP

D.HEATER

CNC

(RED)

X4 X1

MV

GRILLE

FAN

(

WHT

)

1 3 5

1 2 3

1 2 3 6 7 4 8 9 5

10

BLK

WHT

RED

C

MF

X4

X1

BCR

1 2 3

3
2
1

CNSK
(RED)

2
1

CN2S
(WHT)

DC

13.1V

P.B

TO
OUTDOOR
UNIT

TB4

S1
S2
S3

YLW
ORN

YLW
ORN

BRN

5

5

MV5MV5MV

H2

Please set the voltage using the
remote controller.
For the setting method, please refer to
the indoor unit Installation Manual.

SW1

SW2

Table 1

Table 2

Service board

Service board

MODELS
PLA-A,AA

1 2 3 4 5

ON
OFF

1 2 3 4 5

ON
OFF

MODELS

PLA-A12AA

Service board

1 2 3 4 5

ON
OFF

MODELS

PLA-A30AA

1 2 3 4 5

ON
OFF

PLA-A18AA

1 2 3 4 5

ON
OFF

PLA-A36AA

1 2 3 4 5

ON
OFF

PLA-A24AA

1 2 3 4 5

ON
OFF

PLA-A42AA

w1

NOTES:

1. Symbols used in wiring diagram above are, : Connector, : Terminal (block).

2. Indoor and outdoor connecting wires have polarities, make sure to match
terminal numbers (S1, S2, S3) for correct wirings.

3. Since the outdoor side electric wiring may change, be sure to check the outdoor
unit electric wiring diagram for servicing.

4. This diagram shows the wiring of Indoor and Outdoor connecting wires
(specification of 230V), adopting superimposed system of power and signal.

w1. Use copper supply wires.

Check code

Symptom

Check code

Symptom

P1 Abnormality of room temperature thermistor(TH1)

Fb

Abnormality of indoor controller board

U*, F*

Abnormality in outdoor unit. Refer to outdoor unit wiring diagram.

FFFF

No corresponding unit

————

No trouble generated in the past

P2 Abnormality of pipe temperature thermistor / Liquid(TH2)
P4 Abnormality of drain sensor(DS)
P5 Malfunction of drain-up machine
P6 Freezing / overheating protection is working.
P8 Abnormality of pipe temperature
P9 Abnormality of pipe temperature thermistor / Cond. / Eva.(TH5)

E0-E5

Abnormality of the signal transmission between remote
controller and indoor unit

E6-EF

Abnormality of the signal transmission between indoor unit and outdoor unit

[Self-diagnosis]

1. For details on how to operate self-diagnosis with the wireless remote control, refer to the technical manuals etc.

2. For the wired remote control : When you quickly press twice the CHECK switch on the remote control,
the unit begins self-diagnosis, and Check Codes generated in the past appear on the display.
For check Codes and Symptoms refer to the table below.

[LEGEND]

P.B

INDOOR POWER BOARD

SYMBOL NAME
I.B

INDOOR CONTROLLER BOARD

FUSE FUSE (6.3A/250V)

ZNR VARISTOR

CN2L CONNECTOR<LOSSNAY>

BCR FAN CONTROL ELEMENT
CN32 CONNECTOR<REMOTE SWITCH>

CN41 CONNECTOR<HA TERMINAL-A>
CN51

CONNECTOR<CENTRALLY CONTROL>

SW1

SWITCH <MODEL SELECTION>wSee Table 1.

SW2

SWITCH <CAPACITY CODE>wSee Table 2.
SWE SWITCH<EMERGENCY OPERATION>
X1 RELAY<DRAIN PUMP>
X4 RELAY<FAN MOTOR>

POWER SUPPLY<R.B>

LED1 POWER SUPPLY<I.B>
LED2

TRANSMISSION<INDOOR-OUTDOOR>LED3

C

CAPACITOR<FAN MOTOR>

SYMBOL NAME

W.B

WIRELESS REMOTE CONTROLLER BOARD

RECEIVING UNIT

BUZZER
LED<RUN INDICATOR >
LED<HOT ADJUST>

SWITCH<HEATING ON/OFF>
SWITCH<COOLING ON/OFF>

FAN MOTOR
VANE MOTOR

MF
MV

DEW PREVENTION HEATER

H2

DRAIN-UP MACHINE

DP

DRAIN SENSOR

DS

TB4

TERMINAL BLOCK<INDOOR/OUTDOOR
CONNECTING LINE>
TERMINAL BLOCK<REMOTE CONTROLLER
TRANSMISSION LINE >
ROOM TEMP.THERMISTOR
<32°F/15kΩ, 77°F/5.2kΩ DETECT>
PIPE TEMP.THERMISTOR/LIQUID
<32°F/15kΩ, 77°F/5.2kΩ DETECT>
COND./EVA.TEMP.THERMISTOR
<32°F/15kΩ, 77°F/5.2kΩ DETECT>

TB5,TB6

TH5

TH1
TH2

WIRED REMOTE CONTROLLER BOARD

R.B

RU

BZ
LED1
LED2

SW1
SW2

NAMESYMBOL

WIRING DIAGRAM

PLA-A12AA PLA-A18AA PLA-A24AA PLA-A30AA PLA-A36AA PLA-A42AA
PLA-A12AA1 PLA-A18AA1 PLA-A24AA1 PLA-A30AA1 PLA-A36AA1 PLA-A42AA1

12

Thermistor TH2
Pipe temperature (Liquid)

Distributor
with strainer (#50)

Thermistor TH5
(Cond./ Eva. temperature)

Thermistor TH1
(Room temperature)

Refrigerant flow in cooling
Refrigerant flow in heating

Strainer (#50)

Strainer (#50)

Heat exchanger

Refrigerant GAS pipe connection
(Flare)

Refrigerant LIQUID pipe connection
(Flare)

9

REFRIGERANT SYSTEM DIAGRAM

PLA-A12AA PLA-A18AA PLA-A24AA PLA-A30AA PLA-A36AA PLA-A42AA
PLA-A12AA1 PLA-A18AA1 PLA-A24AA1 PLA-A30AA1 PLA-A36AA1 PLA-A42AA1

13

10 TROUBLESHOOTING

Unit conditions at service

Error code

Actions to be taken for service (summary)

The inferior phenomenon is
reoccurring.

Displayed

Not displayed

Judge what is wrong and take a corrective action
according to “SELF-DIAGNOSIS ACTION TABLE” (10-3).

Identify the cause of the inferior phenomenon and take
a corrective action according to “TROUBLESHOOTING
BY INFERIOR PHENOMENA ” (10-4).

The inferior phenomenon is
not reoccurring.

Logged

Not logged

1Consider the temporary defects such as the work of
protection devices in the refrigerant circuit including
compressor, poor connection of wiring, noise and etc.
Re-check the symptom, and check the installation
environment, refrigerant amount, weather when the
inferior phenomenon occurred, and wiring related.
2Reset error code logs and restart the unit after finishing
service.
3There is no abnormality in electrical components,
controller boards, and remote controller.

1Recheck the abnormal symptom.
2Identify the cause of the inferior phenomenon and take

a corrective action according to “TROUBLESHOOTING
BY INFERIOR PHENOMENA ” (10-4).
3Continue to operate unit for the time being if the cause
is not ascertained.
4There is no abnormality in electrical components,
controller boards, remote controller etc.

10-1. TROUBLESHOOTING

<Error code display by self-diagnosis and actions to be taken for service (summary)>

Present and past error codes are logged and displayed on the wired remote controller or controller board of outdoor unit.
Actions to be taken for service and the inferior phenomenon reoccurrence at field are summarized in the table below. Check
the contents below before investigating details.

14

10-2. MALFUNCTION-DIAGNOSIS METHOD BY REMOTE CONTROLLER

ON/OFF

TEMP

FAN

VANE

MODE

CHECK

LOUVER

TEST RUN

AUTO STOP

AUTO START

h

min

RESET

SET

CLOCK

CHECK

CHECK
display

Temperature
button

CHECK
button

Refrigerant
address
display

HOUR
button

ON/OFF
button

<In case of trouble during operation>

When a malfunction occurs to the air conditioner, both indoor unit and outdoor unit will stop and operation lamp blinks to
inform unusual stop.

<Malfunction-diagnosis method at maintenance service>

[Procedure]

1. Press the CHECK button twice.

• "CHECK" lights, and refrigerant
address "00" blinks.

• Check that the remote controller's
display has stopped before continuing.

2. Press the temperature
buttons.

3. Point the remote controller at the

sensor on the indoor unit and
press the HOUR button.

4. Point the remote controller at the

sensor on the indoor unit and
press the ON/OFF button.

• Select the refrigerant address of the
indoor unit for the self-diagnosis.

Note: Set refrigerant address using the

outdoor unit’s DIP switch (SW1).
(For more information, see the
outdoor unit installation manual.)

• If an air conditioner error occurs, the
indoor unit's sensor emits an intermit­tent buzzer sound, the operation light
flashes, and the error code is
output.
(It takes 3 seconds at most for error
code to appear.)

• The check mode is cancelled.

To be continued to the next page.

15

[Output pattern A] Errors detected by indoor unit

[Output pattern B]

E9

*1If the beeper does not sound again after the initial

2 beeps to confirm the self-check start signal was received and

the OPERATION INDICATOR lamp does not come on,

there are no error records.

*2If the beeper sounds 3 times continuously “beep, beep, beep (0.4 + 0.4 + 0.4 sec.)” after the initial 2 beeps to confirm

the self-check start signal was received, the specified refrigerant address is incorrect.

OPERATION
INDICATOR
lamp blinking
pattern

Beep Beep Beep Beep Beep

Beep Beep

Off

Approx. 2.5 sec.OnApprox. 3 sec.On0.5 sec.On0.5 sec.On0.5 sec.

On

0.5 sec.

Off

Approx. 2.5 sec.OnApprox. 3 sec.On0.5 sec.On0.5 sec.

· · · Repeated

Number of blinks/beeps in pattern indicates the check
code in the following table (i.e., n=5 for “U2”)

Number of blinks/beeps in pattern indicates
the check code in the following table

n

th

1st2nd3

rd

1st2

nd

Self-check
starts
(Start signal
received)

Beeper sounds

[Output pattern B] Only A-CONTROL

OPERATION
INDICATOR
lamp blinking
pattern

Beep

Beep Beep Beep Beep Beep Beep

Off

Approx. 2.5 sec.On0.5 sec.On0.5 sec.On0.5 sec.

On

0.5 sec.

Off

Approx. 2.5 sec.On0.5 sec.On0.5 sec.

· · · Repeated

Number of blinks/beeps in pattern indicates the check
code in the following table (i.e., n=5 for “P5”)

Number of blinks/beeps in pattern indicates
the check code in the following table

n

th

1st2nd3

rd

1st2

nd

Self-check
starts
(Start signal
received)

Beeper sounds

• Refer to the following tables for details on the check codes.
[Output pattern A]

Beeper sounds/OPERATION

INDICATOR lamp blinks 1 Check code

Symptom Remark

(Number of times)

Wireless remote controller

Wired remote controller

Beeper sounds/OPERATION

INDICATOR lamp blinks 1 Check code

(Number of times)

Wireless remote controller

Wired remote controller

1P1

Intake sensor error

P9

Pipe (TH5) sensor error

2

P2

Pipe (TH2) sensor error

3 E6,E7

Indoor/outdoor unit communication error

4P4

Drain sensor error

5

P5
PA

Drain pump error
Forced compressor stop

6P6

Freezing/Overheating protection operation

7EE

Communication error between indoor and outdoor units

8P8

Pipe temperature error

9 E4, E5

Remote controller signal receiving error

10

–

11

–

–
–

Errors detected by unit other than indoor unit (outdoor unit, etc.)

Symptom Remark

1

Indoor/outdoor unit communication error

2

(Transmitting error) (Outdoor unit)

3

Open/short of outdoor unit thermistors

4

Compressor overcurrent interruption (When compressor locked)

5

Abnormal high discharging temperature/49C worked/
insufficient refrigerant

6

Abnormal high pressure (63H worked)/Overheating
protection

operation

7

Abnormal temperature of heatsink

8

Outdoor unit fan

protection

stop

9

Compressor overcurrent interruption/Abnormal of power module

10

Abnormality of superheat due to low discharge temperature

11

Abnormality such as overvoltage or voltage shortage and
abnormal synchronous signal to main circuit/Current sensor error

12
13

U2

U5

UP
U3,U4
UF

U1,Ud

U8
U6
U7

U9,UH

Others

–
–

–
–

14

Other errors (Refer to the technical manual for the outdoor unit.)

As for outdoor
unit, refer to
outdoor unit's
service manual.
For details, check
the LED display
of the outdoor
controller board.

12 Fb

Indoor unit control system error (memory error, etc.)

–

E0, E3

– E1, E2

Remote controller control board error

Remote controller transmission error

Compressor overcurrent interruption

16

•

If the unit cannot be operated properly after the test run has been performed, refer to the following table to find out the cause.

Symptom

Cause

Wired remote controller LED 1, 2 (PCB in outdoor unit)

On the wireless remote controller with condition above, following phenomena take place.

• No signals from the remote controller can be received.

• Operation lamp is blinking.

• The buzzer makes a short ping sound.

PLEASE WAIT

PLEASE WAIT → Error code

Display messages do not
appear even when operation
switch is turned ON (operation
lamp does not light up).

For about 2
minutes after
power-on

Subsequent to
about 2 minutes
after power-on

After LED 1, 2 are lighted, LED 2 is
turned off, then only LED 1 is

Only LED 1 is lighted. →

LED 1, 2 blink.

Only LED 1 is lighted.

→

LED 1 blinks twice,
LED 2 blinks once.

•

For about 2 minutes after power-on,operation
of the remote controller is not possible
due to system start-up. (Correct operation)

•Connector for the outdoor unit’s protection
device is not connected.

•Reverse or open phase wiring for the outdoor
unit’s power terminal block (L1, L2, GR)

•Incorrect wiring between indoor and outdoor
units (incorrect polarity of S1, S2, S3)

•Remote controller wire short

Note:
Operation is not possible for about 30 seconds after cancellation of function selection. (Correct operation)

For description of each LED (LED1, 2, 3) provided on the indoor controller, refer to the following table.

LED1 (power for microcomputer) Indicates whether control power is supplied. Make sure that this LED is

always lit.

LED2 (power for remote controller)

Indicates whether power is supplied to the remote controller.
This LED lights only in the case of the indoor unit which is connected to the
outdoor unit refrigerant address “0”.

LED3 (communication between indoor and
outdoor units)

Indicates state of communication between the indoor and outdoor units.
Make sure that this LED is always blinking.

lighted.

(Correct operation)

• On wireless remote controller
The continuous buzzer sounds from receiving section of indoor unit.

Blink of operation lamp

• On wired remote controller

1Check code displayed in the LCD.

17

10-3. SELF-DIAGNOSIS ACTION TABLE

Error Code

P1

P2

P4

P5

Abnormal

Room temperature thermistor (TH1)

1 The unit is in 3-minute resume preven-

tion mode if short/open of thermistor is
detected. Abnormal if the unit does not
reset normally after 3 minutes. (The
unit returns to normal operation, if it
has been reset normally.)

2 Constantly detected during cooling,

drying, and heating operation.
Short: 90:(194˚F) or more
Open: -40:(-40˚F) or less

Pipe temperature thermistor/Liquid
(TH2)

1 The unit is in 3-minute resume

prevention mode if short/open of
thermistor is detected. Abnormal if the
unit does not reset normally after 3 min­utes. (The unit returns to normal opera­tion, if it has been reset normally.)

2 Constantly detected during cooling,

drying, and heating (except defrosting)
operation.
Short: 90:(194˚F) or more
Open: -40:(-40˚F) or less

Drain sensor (DS)

1 Suspensive abnormality, if short/open of

thermistor is detected for 30 seconds
continuously.
Turn off compressor and indoor fan.
Short/open is detected for 30 seconds con-

2

tinuously during suspensive abnormality.
(The unit returns to normal operation, if
it has been reset normally.)

3 Detect the following condition.

• During cooling and drying operation

• In case that pipe <liquid> temperature

- room temperature <-10deg

(Except defrosting)

• When pipe <liquid> temperature or
room temperature is short/open tem­perature.

• During drain pump operation

Malfunction of drain pump (DP)

1 Suspensive abnormality, if thermistor

of drain sensor heats itself and
temperature rises slightly. Turn off
compressor and indoor fan.

2 Drain pump is abnormal if the condition

above is detected during suspensive
abnormality.

3 Constantly detected during drain pump

operation.

point and detection method

1 Defective thermistor
2 Contact failure of connector

3 Breaking of wire or contact
4 Defective indoor controller

1 Defective thermistor
2 Contact failure of connector

3 Breaking of wire or contact
4 Defective refrigerant circuit is

5 Defective indoor controller board

1 Defective thermistor
2 Contact failure of connector

3 Breaking of wire or contact
4 Defective indoor controller board

1 Malfunction of drain pump
2 Defective drain

3 Attached drop of water at the

4 Defective indoor controller board

Note: Refer to the manual of outdoor unit for the details of display

such as F, U, and other E.

Cause

characteristics
(CN20) on the indoor controller

board (Insert failure)
failure of thermistor wiring
board

characteristics
(CN21) on the indoor controller

board (Insert failure)
failure of thermistor wiring
causing thermistor temperature

of 90:(194˚F) or more or

-40:(-40˚F) or less.

characteristics
(CN31) on the indoor controller

board (Insert failure)
failure of drain sensor wiring

Clogged drain pump
Clogged drain pipe

drain sensor

• Drops of drain trickles from
lead wire.

• Clogged filter is causing
wave of drain.

Countermeasure

1–3 Check resistance value of thermistor.

• • • • • • • • • • •

0: (32˚F)
10:(50˚F)
20:(68˚F)
30:(86˚F)
40:(104˚F)

• • • • • • • • • • • • •

• • • • • • • • • • • • •

• • • • • • • • • • • • •

• • • • • • • • • • • •

15.0k"

9.6k"

6.3k"

4.3k"

3.0k"
If you put force on (draw or bend) the lead wire
with measuring resistance value of thermistor
breaking of wire or contact failure can be detected.
2 Check contact failure of connector (CN20) on

the indoor controller board. Refer to 10-7.
Turn the power on again and check restart
after inserting connector again.

4 Check room temperature display on remote

controller.
Replace indoor controller board if there is abnor­mal difference with actual room temperature.

Turn the power off, and on again to operate
after check.

1–3 Check resistance value of thermistor.
For characteristics, refer to (P1) above.
2 Check contact failure of connector (CN21) on

the indoor controller board. Refer to 10-7.
Turn the power on and check restart after
inserting connector again.

4 Check pipe <liquid> temperature with remote

controller in test run mode. If pipe <liquid>
temperature is extremely low (in cooling
mode) or high (in heating mode), refrigerant
circuit may have defect.

5 Check pipe <liquid> temperature with remote

controller in test run mode. If there is extreme
difference with actual pipe <liquid> temperature,
replace indoor controller board.

Turn the power off, and on again to operate
after check.

1–3 Check resistance value of thermistor.

0: (32˚F)
10:(50˚F)
20:(68˚F)
30:(86˚F)
40:(104˚F)

• • • • • • • • • • • •

• • • • • • • • • • • •

• • • • • • • • • • • •

• • • • • • • • • • • •

• • • • • • • • • •

6.0k"

3.9k"

2.6k"

1.8k"

1.3k"

2 Check contact failure of connector (CN31) on

the indoor controller board. Refer to 10-7.
Turn the power on again and check restart
after inserting connector again.

4 Replace indoor controller board if drain

pump operates with the line of drain sensor
connector CN31-1 and 2 is short-circuited,
and abnormality reappears.

Turn the power off, and on again to operate
after check.

1 Check if drain pump works.
2 Check drain function.
3 Check the setting of lead wire of drain sensor

and check clogs of the filter.

4 Replace indoor controller board if drain

pump operates with the line of drain sensor
connector CN31-1 and 2 is short-circuited
and abnormality reappears.
Refer to 10-7.

Turn the power off, and on again to operate
after check.

18

Error Code

Abnormal

Freezing/overheating protection is
working

1 Freezing protection (Cooling mode)

The unit is in 6-minute resume prevention
mode if pipe <liquid or condenser/evap­orator> temperature stays under

-15:(5˚F) for 3 minutes, 3 minutes after
the compressor started. Abnormal if it
stays under -15:(5˚F) for 3 minutes
again within 16 minutes after 6-minute
resume prevention mode.

point and detection method

Cause

(Cooling or drying mode)

1 Clogged filter (reduced airflow)
2 Short cycle of air path
3 Low-load (low temperature)

operation out of the tolerance
range

4 Defective indoor fan motor

• Fan motor is defective.

• Indoor controller board is
defective.

5 Defective outdoor fan control
6 Overcharge of refrigerant
7 Defective refrigerant circuit

(clogs)

Countermeasure

(Cooling or drying mode)

1 Check clogs of the filter.
2 Remove shields.

4 Measure the resistance of fan motor's winding.

Measure the output voltage of fan's connector
(FAN) on the indoor controller board.
WThe indoor controller board should be

normal when voltage of AC 208/230V is
detected while fan motor is connected.
Refer to 10-7.

5 Check outdoor fan motor.
67 Check operating condition of refrigerant

circuit.

P6

P8

2 Overheating protection (Heating mode)

The units is in 6-minute resume
prevention mode if pipe <condenser /
evaporator> temperature is detected as
over 70:(158˚F) after the compressor
started. Abnormal if the temperature of
over 70:(158˚F) is detected again with­in 10 minutes after 6-minute resume
prevention mode.

Pipe temperature

<Cooling mode>
Detected as abnormal when the pipe tem­perature is not in the cooling range 3 min­utes after compressor start and 6 minutes
after the liquid or condenser/evaporator pipe
is out of cooling range.
Note 1) It takes at least 9 minutes to

detect.

Note 2) Abnormality P8 is not detected in

drying mode.
Cooling range
TH: Lower temperature between liquid pipe

TH1: Intake temperature
<Heating mode>
When 10 seconds have passed after the
compressor starts operation and the hot
adjustment mode has finished, the unit is
detected as abnormal when
condenser/evaporator pipe temperature is
not in heating range within 20 minutes.

:-3 deg C[-5.4deg F]]

temperature (TH2) and
condenser/evaporator temperature
(TH5)

(TH-TH1)

(Heating mode)

1 Clogged filter (reduced airflow)
2 Short cycle of air path
3 Overload (high temperature)

operation beyond the tolerance
range

4 Defective indoor fan motor

• Fan motor is defective.

• Indoor controller board is
defective.

5 Defective outdoor fan control
6 Overcharge of refrigerant
7 Defective refrigerant circuit

(clogs)

8 Bypass circuit of outdoor unit

is defective.

1 Slight temperature difference

between indoor room
temperature and pipe <liquid
or condenser / evaporator>
temperature thermistor

• Shortage of refrigerant

• Disconnected holder of pipe
<liquid or condenser /

evaporator> thermistor

• Defective refrigerant circuit

2 Converse connection of

extension pipe (on plural units
connection)

3 Converse wiring of indoor/

outdoor unit connecting wire
(on plural units connection)

4 Defective detection of indoor

room temperature and pipe
<condenser / evaporator>
temperature thermistor

5 Stop valve is not opened

completely.

(Heating mode)

1 Check clogs of the filter.
2 Remove shields.

4

Measure the resistance of fan motor's winding.
Measure the output voltage of fan's connector
(FAN) on the indoor controller board.
WThe indoor controller board should be

normal when voltage of AC 208/230V is
detected while fan motor is connected.
Refer to 10-7.

5 Check outdoor fan motor.
6~8Check operating condition of refrigerant

circuit.

1~4 Check pipe <liquid or condenser /

evaporator> temperature with room
temperature display on remote controller
and outdoor controller circuit board.
Pipe <liquid or condenser / evaporator>
temperature display is indicated by setting
SW2 of outdoor controller circuit board as
follows.

Conduct temperature check with outdoor
controller circuit board after connecting

(

‘A-Control Service Tool(PAC-SK52ST)’.

23Check converse connection of extension

pipe or converse wiring of indoor/outdoor
unit connecting wire.

)

Note 3) It takes at least 27 minutes to

detect abnormality.

Note 4) It excludes the period of defrosting

(Detection restarts when defrosting
mode is over)

Heating range

:3 deg C[5.4deg F][

(TH5-TH1)

19

Error Code

P9

E0

or

E4

E3

or

E5

Abnormal point and detection method

Pipe temperature thermistor /
Condenser-Evaporator (TH5)

1 The unit is in 3-minute resume protec-

tion mode if short/open of thermistor is
detected. Abnormal if the unit does not
get back to normal within 3 minutes.
(The unit returns to normal operation, if
it has been reset normally.)

2 Constantly detected during cooling, dry-

ing, and heating operation (except
defrosting)
Short: 90:(194˚F) or more
Open: -40:(-40˚F) or less

Remote controller transmission
error(E0)/signal receiving error(E4)

1 Abnormal if main or sub remote con-

troller cannot receive any transmission
normally from indoor unit of refrigerant
address “0” for 3 minutes.
(Error code : E0)

2 Abnormal if sub-remote controller could

not receive for any signal for 2 minutes.
(Error code: E0)

1 Abnormal if indoor controller board can

not receive any data from remote con­troller board or normally from other
indoor controller board for 3 minutes.
(Error code: E4)

2 Indoor controller board cannot receive

any signal from remote controller for 2
minutes. (Error code: E4)

Remote controller transmission
error(E3)/signal receiving error(E5)

1 Abnormal if remote controller could not

find blank of transmission path for 6 sec­onds and could not transmit.

(Error code: E3)

2 Remote controller receives transmitted

data at the same time, compares the
data, and when detecting it, judges
different data to be abnormal 30
continuous times. (Error code: E3)

1 Abnormal if indoor controller board could

not find blank of transmission path.

(Error code: E5)

2 Indoor controller board receives trans-

mitted data at the same time, compares
the data,and when detecting it, judges
different data to be abnormal 30
continuous times. (Error code: E5)

Cause

1 Defective thermistor

characteristics

2 Contact failure of connector

(CN29) on the indoor controller
board (Insert failure)

3 Breaking of wire or contact

failure of thermistor wiring

4 Temperature of thermistor is

90:(194˚F) or more or -40:
(-40˚F) or less caused by
defective refrigerant circuit.

5 Defective indoor controller

board

1 Contact failure at transmission

wire of remote controller

2 All remote controllers are set

as “sub” remote controller. In
this case, E0 is displayed on
remote controller, and E4 is
displayed at LED (LED1, LED2)
on the outdoor controller circuit
board.

3 Miswiring of remote controller
4 Defective transmitting receiving

circuit of remote controller

5 Defective transmitting receiving

circuit of indoor controller board
of refrigerant address “0”

6 Noise has entered into the

transmission wire of remote
controller.

1 2 remote controller are set as

“main.” (In case of 2 remote
controllers)

2 Remote controller is connected

with 2 indoor units or more.

3 Repetition of refrigerant

address

4 Defective transmitting receiving

circuit of remote controller

5 Defective transmitting receiving

circuit of indoor controller board

6 Noise has entered into trans-

mission wire of remote controller.

Countermeasure

1–3 Check resistance value of thermistor.

For characteristics, refer to (P1) above.

2 Check contact failure of connector (CN29)

on the indoor controller board. Refer to 10-7.
Turn the power on and check restart after
inserting connector again.

4 Operate in test run mode and check pipe

<condenser / evaporator> temperature with
outdoor controller circuit board. If pipe
<condenser / evaporator> temperature is
extremely low (in cooling mode) or high (in
heating mode), refrigerant circuit may have
defect.

5 Operate in test run mode and check pipe

<condenser / evaporator> temperature with
outdoor control circuit board. If there is
exclusive difference with actual pipe
<condenser / evaporator> temperature
replace indoor controller board.
There is no abnormality if none of above
comes within the unit.
Turn the power off and on again to operate.

In case of checking pipe temperature
with outdoor controller circuit board,
be sure to connect A-control service

(

tool (PAC-SK52ST).

1 Check disconnection or looseness of indoor

unit or transmission wire of remote controller.

2 Set one of the remote controllers “main”

if there is no problem with the action above.

3 Check wiring of remote controller.

• Total wiring length: max. 500m
(Do not use cable o 3 or more)

• The number of connecting indoor units:
max. 16 units

• The number of connecting remote con­troller: max. 2 units

When the above-mentioned problem 1~3 are not seen.
4 Diagnose remote controllers.

a) When “RC OK” is displayed,

remote controllers have no problem.
Turn the power off, and on again to
check. If abnormality generates again,
replace indoor controller board.

b) When “RC NG” is displayed,

replace remote controller.
c) When “RC E3” is displayed,
d) When “ERC 00-06” is displayed,
[ c),d)→Noise may be causing abnormality. ]

∗ If the unit is not normal after replacing

indoor controller board in group control,
the indoor controller board of address
“0” may be abnormal.

1 Set a remote controller to main, and the

other to sub.

2 Remote controller is connected with only 1

indoor unit.

3 The address changes to a separate setting.
4~6 Diagnose remote controller.

a) When “RC OK” is displayed, remote con-

trollers have no problem.

Turn the power off, and on again to check.
When becoming abnormal again, replace

indoor controller board.
b)When “RC NG” is displayed, replace

remote controller.
c)When “RC E3” or “ERC 00-66” is displayed,

noise may be causing abnormality.

)

20

Error Code

E6

E7

Fb

E1

or

E2

Abnormal point and detection method

Indoor/outdoor unit communication
error (Signal receiving error)

1 Abnormal if indoor controller board

cannot receive any signal normally for 6
minutes after turning the power on.

2 Abnormal if indoor controller board

cannot receive any signal normally for 3
minutes.

3 Consider the unit as abnormal under the

following condition: When 2 or more
indoor units are connected to 1
outdoor unit, indoor controller board
cannot receive a signal for 3 minutes
from outdoor controller circuit board, a
signal which allows outdoor controller
circuit board to transmit signals.

Indoor/outdoor unit communication
error (Transmitting error)

Abnormal if “1” receiving is detected 30
times continuously though indoor controller
board has transmitted “0”.

Indoor controller board

Abnormal if data cannot be normally read
from the nonvolatile memory of the indoor
controller board.

Remote controller control board

1 Abnormal if data cannot be normally

read from the nonvolatile memory of the
remote controller control board.

(Error code: E1)

2 Abnormal if the clock function of remote

controller cannot be normally operated.

(Error code: E2)

Cause

1 Contact failure, short circuit or,

miswiring (converse wiring) of
indoor/outdoor unit connecting
wire

2 Defective transmitting receiving

circuit of indoor controller board

3 Defective transmitting receiving

circuit of indoor controller board

4 Noise has entered into indoor/

outdoor unit connecting wire.

1 Defective transmitting receiving

circuit of indoor controller board

2 Noise has entered into power

supply.

3 Noise has entered into outdoor

control wire.

1 Defective indoor controller

board

1 Defective remote controller 1 Replace remote controller.

∗ Check LED display on the outdoor control cir-

cuit board. (Connect A-control service tool,
PAC-SK52ST.)
Refer to EA-EC item if LED displays EA-EC.

1 Check disconnection or looseness of indoor/

outdoor unit connecting wire of indoor unit or
outdoor unit.
Check all the units in case of twin indoor

unit system.

2-4 Turn the power off, and on again to

check. If abnormality generates again,
replace indoor controller board or outdoor
controller circuit board.

∗ Other indoor controller board may have

defect in case of twin indoor unit system.

1-3 Turn the power off, and on again to

check. If abnormality generates again,
replace indoor controller board.

1 Replace indoor controller board.

Countermeasure

PA
(2502)
(2500)

Forced compressor stop
(due to water leakage abnormality)

When the intake temperature subtracted

1

with liquid pipe temperature is less than

-10:(14˚F), drain sensor detects
whether it is soaked in the water or not
at the interval of 90 seconds.

pump will start operating when the drain
sensor detects to be soaked in the
water.)

2 The unit has a water leakage abnormality

when the following conditions, a and b,
are satisfied while the above-mentioned
detection is performed.
a) The drain sensor detects to be

soaked in the water 10 times in a row.

b) The intake temperature subtracted

with liquid pipe temperature is detect­ed to be less than -10:(14˚F) for a
total of 30 minutes. (When the drain
sensor detects to be NOT soaked in
the water, the detection record of a
and b will be cleared.)

3 The drain sensor detection is performed

in operations other than cooling. (When
the unit stops operating, during heating
or fan operation, when the unit stops
because of some abnormality)

*Once the water leakage abnormality is

detected, abnormality state will not be
released until the main power is reset.

(Drain

1 Drain pump trouble
2 Drain defective

· Drain pump clogging

· Drain pipe clogging

3 Open circuit of drain sensor

side heater

4 Contact failure of drain sensor

connector

5 Dew condensation on drain

sensor

· Drain water trickles along
lead wire.

· Drain water waving due to filter
clogging

6 Extension piping connection

difference at twin system

7 Miswiring of indoor/ outdoor

connecting at twin system

8 Room temperature thermistor /

liquid pipe temperature thermis­tor detection is defective.

1 Check the drain pump.
2 Please confirm whether water can be

drained.

3 Confirm the resistance of the drain sensor.

4 Check the connector contact failure.

5 Check the drain sensor leadwire mounted.

Check the filter clogging.

6 Check the piping connection.

7 Check the indoor/ outdoor connecting wires.

8 Check the room temperature display of

remote controller.
Check the indoor liquid pipe temperature
display of outdoor controller board.

21

10-4. TROUBLESHOOTING BY INFERIOR PHENOMENA

Note: Refer to the manual of outdoor unit for the detail of remote controller.

Phenomena

(1)LED2 on indoor controller board

is off.

• When LED1 on indoor controller board is also off.

1 Power supply of rated voltage is not supplied to out-

door unit.

2 Defective outdoor controller circuit board

3 Power supply of 208/230V is not supplied to indoor

unit.

4 Defective indoor power board

5 Defective indoor controller board

(For the separate indoor/outdoor unit power sup-

ply system)

1 Power supply of 208/230V AC is not supplied to

indoor unit.

2 The connectors of the optional replacement kit are

not used.

3 Defective indoor controller board

4 Defective indoor power board

Cause

Countermeasure

1 Check the voltage of outdoor power

supply terminal block (L1,L2).

• When AC 208/230V is not detected,
check the power wiring to outdoor unit
and the breaker.

• When AC 208/230V is detected,

check 2 (below).

2 Check the voltage between outdoor

terminal block S1 and S2.

• When AC 208/230V is not detected.

—Check the fuse on outdoor controller
circuit board.

—Check the wiring connection.

• When AC 208/230V is detected,

check 3 (below).

3 Check the voltage between indoor terminal

block S1 and S2.

• When AC 208/230V is not detected,
check indoor/outdoor unit connecting
wire for miswiring.

• When AC 208/230V is detected,

check 4 (below).

4 Check voltage output from CN2S on indoor

power board (DC13.1V). Refer to 10-7-1.

• When no voltage is output, check the

wiring connection.

• When output voltage is between

DC12.5V and DC13.7V, check 5
(below).

5 Check the wiring connection between

indoor controller board and indoor power
board. Check the fuse on indoor controller
board. If no problems are found, indoor
controller board is defective.

1 Check the voltage of indoor power supply

terminal block (L1,L2).

• When AC208/230V is not detected,

check the power supply wiring.

• When AC208/230V is detected, check

2 (below).

2 Check that there is no problem in the

method of connecting the connectors.

• When there are problems in the method

of connecting the connectors, connect
the connector correctly referring to instal­lation manual of an optional kit.

• When there is no problem in the

method of connecting the connectors,
check 3 (below).

3 Check voltage output from CNDK on

indoor controller board.

• When AC208/230V is not detected.

—Check the fuse on indoor controller board.

—Check the wiring connection between

indoor power supply terminal block and
CND on indoor controller board.

• When AC208/230V is detected, check

4 (below).

4 Check voltage output from CN2S on

indoor power board.

• When no voltage output, check the

wiring connection between CNDK on
indoor controller board and CNSK on
indoor power board.

If no problem are found, indoor power

board is defective.

• When DC12.5~13.7V is detected,

check the wiring connection between
CN2S on indoor power board and
CN2D on indoor power board.

If no problem are found, indoor con-

troller board is defective.

22

Phenomena

(1)LED2 on indoor controller board

is off.

Note: Refer to the manual of outdoor unit for the detail of remote

controller.

Cause

• When LED1 on indoor controller board is lit.

1 Mis-setting of refrigerant address for outdoor unit

(There is no unit corresponding to refrigerant
address “0”.)

Countermeasure

1 Check the setting of refrigerant address

for outdoor unit.
Set the refrigerant address to “0”.
(For grouping control system under
which 2 or more outdoor units are
connected, set one of the units to “0”.)
Set refrigerant address using SW1 (3-6)
on outdoor controller circuit board.

(2)LED2 on indoor controller board

is blinking.

(3)Upward/downward vane

performance failure

• When LED1 on indoor controller board is also blinking.
Connection failure of indoor/outdoor unit connecting
wire

• When LED1 is lit.

1 Miswiring of remote controller wires

Under twin indoor unit system, 2 indoor

wired together.

2 Refrigerant address for outdoor unit is wrong or not

set.

Under grouping control system, there are some units
whose refrigerant address is 0.

3 Shortcut of remote controller wires
4 Defective remote controller

1 The vane is not downward during defrosting and

heat preparation and when the thermostat is OFF in
HEAT mode. (Working of COOL protection function)

2 Vane motor does not rotate.

• Defective vane motor

• Breaking of wire or connection failure of connector

3 Upward/downward vane does not work.

• The vane is set to fixed position.

units are

Check indoor/outdoor unit connecting wire
for connection failure.

1 Check the connection of remote con-

troller wires in case of twin indoor unit
system. When 2 indoor units are wired in
one refrigerant system, connect remote
controller wires to one of those units.

2 Check the setting of refrigerant address

in case of grouping control system.
If there are some units whose refrigerant
addresses are 0 in one group, set one of
the units to 0 using SW1 (3-6) on outdoor
controller circuit board.

34 Remove remote controller wires and

check LED2 on indoor controller board.

• When LED2 is blinking, check the
shortcut of remote controller wires.

• When LED2 is lit, connect remote con­troller wires again and:

if LED2 is blinking, remote controller is
defective; if LED2 is lit, connection fail­ure of remote controller terminal block
etc. has returned to normal.

1 Normal operation (The vane is set to hor-

izontal regardless of remote control.)

2 Check 2 (left).

• Check the vane motor. (Refer to “How
to check the parts”.)

• Check for breaking of wire or connec­tion failure of connector.

3 Normal operation (Each connector on

vane motor side is disconnected.)

(4)Receiver for wireless remote

controller

1 Weak batteries of wireless remote controller
2 Contact failure of connector (CNB) on wireless

remote controller board

(Insert failure)

3 Contact failure of connector (CN90) on indoor con-

troller board (Insert failure)

4 Contact failure of connector between wireless

remote controller board and indoor controller board

23

1 Replace batteries of wireless remote con-

troller.

2~4

Check contact failure of each connector.
If no problems are found of connector,
replace indoor controller board. When
the same trouble occurs even if indoor
controller board is replaced, replace
wireless remote controller board.

10-5. EMERGENCY OPERATION

Receiver

Operation lamp

Emergency operation switch (cooling)

Emergency operation switch (heating)

Mode

Cooling

Heating

Set temperature

Fan speed

Airflow direction

24:, 75-F

High

Downward (70deg)

24:, 75-F

High

Horizontal (30deg)

wEmergency operation will be performed as follows.

10-5-1. When wireless remote controller has troubles or its battery is exhausted

1. Emergency operation is available in such a case using emergency operation switch equipped on the grille.

2. To start operation

• Cooling Operation·······Press (Cooling) switch.

• Heating Operation·······Press (Heating) switch.

wWhen the unit starts operating, the operation lamp is lit.

3. To stop operation

• Press either emergency operation switch (cooling/heating).

10-5-2. When wired remote controller or indoor unit microcomputer has troubles

1. If other defects are not found when trouble occurs, emergency operation starts as the indoor controller board switch (SWE)
is set to ON.
During the emergency operation, the indoor unit is as follows;

(1) Indoor fan high speed operation (2) Drain pump operation

2. For emergency operation of cooling or heating
When emergency operation for COOL or HEAT, setting of the switch (SWE) in the indoor controller board and outdoor unit
emergency operation are necessary.

3. Check items and notices as the emergency operation

(1) Emergency operation cannot be used as follows;

• When the outdoor unit is something wrong.

• When the indoor fan is something wrong.

• When drain overflow protection operation is detected during self-diagnosis. (Error code : P5)

(2) Emergency operation will be serial operation by the power supply ON/OFF.

ON/OFF or temperature, etc. adjustment is not operated by the remote controller.

(3) Do not operate for a long time as cold air is blown when the outdoor unit starts defrosting operation during heat emer-

gency operation.
(4) Cool emergency operation must be within 10 hours. Otherwise, heat exchanger of indoor unit may get frosted.
(5) After completing the emergency operation, return the switch setting, etc. in former state.
(6) Since vane does not work at emergency operation, position the vane slowly by hand.

24

10-6. HOW TO CHECK THE PARTS
PLA-A12AA PLA-A18AA PLA-A24AA PLA-A30AA PLA-A36AA PLA-A42AA
PLA-A12AA1 PLA-A18AA1 PLA-A24AA1 PLA-A30AA1 PLA-A36AA1 PLA-A42AA1

Parts name Check points

Room temperature
thermistor (TH1)

Pipe temperature
thermistor/liquid(TH2)

Condenser/Evaporator
temperature thermistor
(TH5)

Disconnect the connector then measure the resistance using a tester.
(At the ambient temperature 10:(50˚F)~30:(86˚F))

Normal

4.3k"~9.6k"

Abnormal

Open or short

(Refer to the thermistor characteristic graph.)

Vane motor (MV)

Fan motor (MF)

Relay connector

1

Red

White

2

3

Black

Protector
OFF:130:
ON :80i20:

Drain pump (DP)

YLW

1
3

YLW

Drain sensor (DS)

1
2
3

Measure the resistance between the terminals using a tester.
(At the ambient temperature20:(68˚F))

Normal Abnormal

15k" Open or short

Measure the resistance between the terminals using a tester.
(Winding temperature 20:(68˚F))

Motor terminal

1
2
3

or

Relay connector

Red-Black

White-Black

PLA-A12/18/24/30AA
PLA-A12/18/24/30AA

87.2"

104.1"

Normal

1

PLA-A36/42AA
PLA-A36/42AA

32.6"

40.7"

1

Open or short

Measure the resistance between the terminals using a tester.
(Winding temperature 20:(68˚F))

Normal Abnormal

319" Open or short

Measure the resistance between the terminals using a tester.
Measure the resistance after 3 minutes have passed since the power supply was intercepted.
(At the ambient temperature 0:(32˚F)~60:(140˚F))

Normal

0.6k"~6.0k"

Abnormal

Open or short

(Refer to the thermistor characteristic graph.)

Abnormal

25

<Thermistor Characteristic graph>

< Thermistor for drain sensor >

0

1

2

3

4

5

6

7

8

9

10

Resistance (k")

60 80

140

176

-20 0 20 40

-4 32 68 104

:

°F

Temperature

Thermistor for
lower temperature

Room temperature thermistor(TH1)
Pipe temperature thermistor/liquid(TH2)
Condenser/evaporator temperature
thermistor(TH5)

Thermistor R0=15k' ±3%
Fixed number of B=3480 ± 2%

t(:):Rt=15exp { 3480( ) }

T(˚F):Rt=15exp { 3480( ) }

1

273+t

1

273+

T-32

1.8

1

273

1

273

0: (32˚F) 15k'
10: (50˚F) 9.6k'
20: (68˚F) 6.3k'
25: (77˚F) 5.4k'
30: (86˚F) 4.3k'
40:(104˚F) 3.0k'

Thermistor for
drain sensor

<Thermistor for lower temperature>

50

40

30

20

Resistance (k")

10

0

-20 -10 0 10 20 30 40 50

-4 -14 32 50 68 86 104 122:°F
Temperature

Thermistor R0=6.0k' ±5%
Fixed number of B=3390 ±2%

t(:)Rt= 6 exp { 3390( ) }

T(˚F):Rt=6exp { 3390( ) }

1

273+t

1

273+

0: (32˚F) 6.0k'
10: (50˚F) 3.9k'
20: (68˚F) 2.6k'
25: (77˚F) 2.2k'

1

273

T-32

1.8

30: (86˚F) 1.8k'
40:(104˚F) 1.3k'
60:(140˚F) 0.6k'

1

273

26

10-7.TEST POINT DIAGRAM

10-7-1. Power board
PLA-A12AA PLA-A18AA PLA-A24AA
PLA-A30AA PLA-A36AA PLA-A42AA
PLA-A12AA1 PLA-A18AA1 PLA-A24AA1
PLA-A30AA1 PLA-A36AA1 PLA-A42AA1

CN2S
Connect to the indoor controller board (CN2D)
between 1 to 3 12.6-13.7V DC (Pin1 (+))

CNSK
Connect to the indoor controller board
(CNDK)
between 1 to 3 208/230V AC

27

10-7-2. Indoor controller board
PLA-A12AA PLA-A18AA PLA-A24AA PLA-A30AA PLA-A36AA PLA-A42AA
PLA-A12AA1 PLA-A18AA1 PLA-A24AA1 PLA-A30AA1 PLA-A36AA1 PLA-A42AA1

CN2D
Connect to the indoor power board
(CN2S)
(12.5~13.7V DC)

CN3C
Transmission

(Indoor/outdoor)

(0~24V DC)

CNDK
Connect to the indoor

power board (CNSK)

(208/230V AC)

FUSE
(6.3 A 250 V)

CND
Power supply input
(208/230V AC)

LED1
Power supply (I.B)

LED2
Power supply (R.B)

LED3
Transmission (Indoor/outdoor)

CN22
Connect to the terminal
block(TB5)
(Remote controller connecting
wire)
(10.4~14.6V DC)

CN20
Room temperature
thermistor (TH1)

CN21
Pipe temperature
thermistor/Liquid (TH2)

CN29
Condenser/evaporator
temperature thermistor (TH5)

CN31
Drain sensor (DS)

CN90
Connect to the wireless
remote controller board
(CNB)

CNP
Drain-pump output

(DP)

(208/230V AC)
CNC

Dew prevention

heater (H2)

(208/230V AC)

SWE
Emergency operation

FAN
Fan motor output

CN6V
Vane motor output
(MV)

CN41
Connector (HA terminal-A)

CN51
Centrally control

CN24
Heater output
(12V DC)

CN32
Remote switch

CN2L
Connector
(LOSSNAY)

Jumper wire J41, J42
Pair number setting with
wireless remote controller

SW2
Capacity setting

SW1
Model setting

28

10-8. FUNCTIONS OF DIP SWITCH AND JUMPER WIRE

Each function is controlled by the dip switch and the jumper wire on control P.C. board.
SW1 and SW2 are equipped only for service parts.
Model setting and capacity setting are memorized in the nonvolatile memory of the control P.C. board of
the unit.

(Marks in the table below) Jumper wire ( : Short : Open)

Jumper wire

SW1

SW2

J41
J42

Functions

Model
settings

Capacity
settings

Pair number
setting with
wireless
remote
controller

Setting by the dip switch and jumper wire

1

0
1
2

3 ~ 9

Service board

1 2 3 4 5

ON
OFF

Service board

1 2 3 4 5

1 2 3 4 5

1 2 3 4 5

1 2 3 4 5

1 2 3 4 5

1 2 3 4 5

ON
OFF

ON
OFF

ON
OFF

ON
OFF

ON
OFF

ON
OFF

Control PCB setting

J41 J42

MODELS

PLA-A·AA
PLA-A·AA

MODELS

PLA-A12AA
PLA-A12AA1

PLA-A18AA
PLA-A18AA1

PLA-A24AA
PLA-A24AA1

PLA-A30AA
PLA-A30AA1

PLA-A36AA
PLA-A36AA1

PLA-A42AA
PLA-A42AA1

Wireless remote

controller setting

Remarks

<Initial setting>
Wireless remote controller: 0
Control PCB: (for both J41 and J42)
4 pair number settings are supported.
The pair number settings of the wireless remote
controller and indoor control PCB (J41/J42) are
given in the table on the left.
(' ' in the table indicates the jumper wire is disco­nnected.)

JP1

JP3

Unit type
setting

Indoor
controller
board type
setting

Model

Without TH5

With TH5

Indoor controller board type

For product

Service parts

JP1

There is no jumper (JP1) because these models
have the cond./eva. temperature thermistor (TH5).

JP3

29

11

DISASSEMBLY PROCEDURE

PLA-A12AA PLA-A18AA PLA-A24AA PLA-A30AA PLA-A36AA PLA-A42AA
PLA-A12AA1 PLA-A18AA1 PLA-A24AA1 PLA-A30AA1 PLA-A36AA1 PLA-A42AA1

Be careful on removing heavy parts.

OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS

1. Removing the air intake grille

(1) Slide the knob of air intake grille to the direction of the

arrow 1 to open the air intake grille.

(2) Remove the string hook from the panel to prevent the

grille from dropping.

(3) Slide the shaft in the hinge to the direction of the arrow2

and remove the air intake grille.

2. Removing the room temperature thermistor

(1) Remove the screw(✕1) in the room temperature thermistor

holder to remove the holder and the room temperature
thermistor.

(2) Remove the 1 screw from the bell mouth, and unscrew the

other 2 screws (fix to the oval hole which has a different
diameter) to remove the bell mouth.

(3) Hold the holder claw, and remove the room temperature

thermistor and holder.

(4) Disconnect the connector (CN20:red) on the indoor control

board.

Figure 1

Air intake grille

Grille

Air intake grille knob

Photo 1

Screws

Bell mouth

Room
temperature
thermistor

Air intake grille

3. Removing the electrical box

(1) Disconnect the lead wire of the vane motor from the clamp,

and disconnect the white connector (10P).
(2) Remove the room temperature thermistor with the holder.
(3) Remove the bell mouth.(See photo 1)
(4) Disconnect the relay connector in the electrical box.

Red (3P) for fan motor

Disconnect the connector on the indoor controller board.

White (2P) for pipe temperature detecting thermistor

Blue (3P) for drain pump

White (3P) for drain sensor
(5) Remove the 3 screws from the electrical box, loosen

another 2 screws to remove the box.

<Electrical parts in the electrical box>

Indoor controller board

Power board

Terminal block

Capacitor

30

Photo 2

Turbo fan

Electrical
box

Power
board

Nut

Indoor controller board

Capacitor

Terminal

block

Connector

OPERATING PROCEDURE

PHOTOS & ILLUSTRATIONS

4. Removing the fan motor

(1) Remove the bell mouth.(See photo 1)
(2) Remove the electrical box.(See photo 2)
(3) Remove the turbo fan nut.
(4) Pull out the turbo fan.
(5) Disconnect the connector of the fan motor lead wire.
(6) Remove the 4 nuts of the fan motor.

5. Removing the pipe temperature thermistor
and condenser evaporator temperature thermistor

(1) Remove the bell mouth.(See photo 1)
(2) Remove the electrical box.(See photo 2)
(3) Remove the turbo fan.
(4) Remove the screw of the service panel.
(5) Remove the service panel.
(6) Remove the pipe temperature thermistor which is inserted

into the holder installed to the thin copper pipe.

(7) Disconnect the 2-pin white connector.(CN21)

[Condenser/ evaporator temperature thermistor]

(8) Remove the drain pan. (See Photo 6)
(9) Remove the thermistor which is installed into the holder to

the indoor coil.

(10) Disconnect the 2-pin black connector. (CN29)

6. Removing the panel

(1) Remove the air intake grille.(See figure 1)

Corner panel (See figure 2)

(1) Remove the corner screw.
(2) Slide the corner panel to the direction of the arrow3, and

remove the corner panel.

Panel (See photo 5)

(1) Disconnect the connector that connects with the unit.
(2) Remove the 2 screws from the panel and loosen another

2 screws, which fix to the oval holes, have different diame­ters.

(3) Rotate the panel a little to remove the screws.

Photo 3

Photo 4

Figure 2

Corner
panel

Photo 5

Connector

Screw

Fan motor

Nut

Pipe temperature thermistor

Service access

Screw

Connector

Corner
panel

Nut

Panel

Screw

Panel

7. Removing the drain pan

(1) Remove the panel. (See photo 5)
(2) Remove the drain plug (Larger one), drain the remaining

water in the drain pan.
(3) Remove the corner cover. (2 screws)
(4) Remove the bell mouth (See photo 1)
(5) Remove the electrical box. (See photo 2)
(6) Remove the lead wire holder. (1 screw)
(7) Remove the 4 screws and pull out the drain pan.

w Pull out the left and right of the pan gradually.

Be careful not to crack or damage the pan.

31

Photo 6

Drain pan

Screw
Lead

wire
holder

Screw

Drain plug(Larger one) Corner cover

Screw

Screw

OPERATING PROCEDURE PHOTOS & ILLUSTRATIONS

8. Removing the drain pump and drain sensor

(1) Remove the panel. (See photo 5)
(2) Remove the bell mouth. (See photo 1)
(3) Remove the electrical box. (See photo 2)
(4) Remove the drain pan. (See photo 6)
(5) Remove the 3 screws of the drain pump.
(6) Cut the drain hose band, pull out the drain hose from the

drain pump.
(7) Pull out the drain pump.
(8) Remove the drain sensor and the holder.

9. Removing the heat exchanger

(1) Remove the panel. (See photo 5)
(2) Remove the bell mouth. (See photo 1)
(3) Remove the electrical box. (See photo 2)
(4) Remove the drain pan. (See photo 6)
(5) Remove the turbo fan. (See photo 3)
(6) Remove the 3 screws of the piping cover, and pull out

piping cover.
(7) Remove the 4 screws of the outer wall cover, and pull out

the outer wall cover.
(8) Remove the screw of the coil support.
(9) Remove the 2 screws of the coil.

(10) Pull out the heat exchanger.

Photo 7

Screw

Drain hose

Photo 8

Heat exchanger

Coil

support

Fixing band

Coil support

Drain sensor

Screw

Drain pump

Coil screws

Coil
support

32

Photo 9

Screw

Outer wall cover

Piping cover

Screws of
piping cover

12 PARTS LIST (non-RoHS compliant)

ON/OFF

CENTRALLY CONTROLLED

ERROR CODE

CLOCK

ON OFF

˚C

CHECK

CHECK MODE

FILTER

TEST RUN
FUNCTION

˚C

1Hr.

NOT AVAILABLE

STAND BY
DEFROST

TEMP.

No.

Parts No. Parts Name

Specification

Q'ty / set

Remarks

(Drawing No.)

Wiring

Diagram

Symbol

Recom-

mended

Q'ty

1
2
3
4
5
6
7
8

9
10
11

12

AIR OUTLET GRILLE
VANE
CORNER PANEL
L.L FILTER
GRILLE ASSY
VANE MOTOR
VANE BUSH
GEAR (VANE)
GEAR
REMOTE CONTROLLER
CABLE ASSY
SCREW ASSY

1
4
4
1
1
4
8
4
4
1
1
1

MV

R.B

T7W E13 003
T7W E05 002
R01 E03 638
R01 E00 500
R01 E00 691
R01 E00 223
R01 E00 063
R01 E00 040
R01 E01 040
T7W E10 713
T7W E01 305
R01 E00 673

PLA-A12/18/24

/30/36/42AA

Including H2

PANEL PARTS
PLA-A12AA PLA-A18AA PLA-A24AA
PLA-A30AA PLA-A36AA PLA-A42AA

2

3

1

GEAR

9

GEAR

(VANE)

8

VANE

BUSH

7

6

VANE

MOTOR

10

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

3

4

5

11

33

3

No.

Parts No.

Parts Name

Q'ty / set

PLA-A·AA

12 18

24, 30

Wiring

Diagram

Symbol

Recom­mended

Q'ty

1
2

3

4
5
6
7
8
9

TURBO FAN
SPL WASHER
HEAT EXCHANGER
HEAT EXCHANGER
HEAT EXCHANGER
PIPE TEMPERATURE THERMISTOR
CONDENSER / EVAPORATOR TEMPERATURE THERMISTOR
MOTOR CAP
LEAD ASSY(F/M)
FAN MOTOR
RUBBER MOUNT

R01 E28 114
R01 08K 097
T7W H20 480
T7W H34 480
T7W H21 480
T7W E06 202
R01 E32 202
R01 E00 122
T7W E01 304
T7W E12 762
R01 A41 105

1
1
1

1
1
1
1
1
4

1
1

1
1
1
1
1
1
4

TH2
TH5

MF

Remarks

(Drawing No.)

D17D6P70MS

Specification

1
1

1

1
1
1
1
1
4

FUNCTIONAL AND STRUCTURAL PARTS
PLA-A12AA
PLA-A18AA
PLA-A24AA
PLA-A30AA

1

9 8

7

MOTOR CAP

6

SPL WASHER

2

3

5

CONDENSER
EVAPORATOR
TEMPERATURE
THERMISTOR

4

PIPE TEMPERATURE
THERMISTOR

34

FUNCTIONAL AND STRUCTURAL PARTS
PLA-A36AA

9 8

PLA-A42AA

1

7

MOTOR CAP

6

SPL WASHER

No.

Parts No.

1

T7W E02 114

2

R01 08K 097

3

T7W H22 480

4

T7W E06 202

5

R01 E32 202

6

R01 E00 122

7

T7W E01 304

8

T7W E08 762

9

R01 A41 105

2

3

Q'ty / set

Parts Name

TURBO FAN
SPL WASHER
HEAT EXCHANGER
PIPE TEMPERATURE THERMISTOR

CONDENSER / EVAPORATOR TEMPERATURE THERMISTOR

MOTOR CAP
LEAD ASSY(F/M)
FAN MOTOR
RUBBER MOUNT

Specification

D17CP110MS

PLA-A·AA

36, 42

1
1
1
1
1
1
1
1
4

5

CONDENSER
EVAPORATOR
TEMPERATURE
THERMISTOR

4

PIPE TEMPERATURE
THERMISTOR

Remarks

(Drawing No.)

Wiring

Diagram

Symbol

TH2
TH5

MF

Recom­mended

Q'ty

35

No.

Parts No.

Parts Name

Wiring

Diagram

Symbol

Recom­mended

Q'ty

1
2
3
4
5
6
7
8

9
10
11
12
13
14

DRAIN PAN
DRAIN HOSE
DRAIN PUMP
DRAIN SENSOR
SENSOR HOLDER
INDOOR POWER BOARD
INDOOR CONTROLLER BOARD
ROOM TEMPERATURE THERMISTOR
TERMINAL BLOCK
TERMINAL BLOCK
TERMINAL BLOCK
CAPACITOR
DRAIN PLUG
DRAIN PLUG

1
1
1
1
1
1
1
1
1
1
1
1
1
1

DP
DS

P.B

I.B
TH1
TB5
TB4
TB2

C

2P (1, 2)
3P (S1, S2, S3)
3P (L1, L2, GR)

3.0+ 440V

T7W E09 529
T7W E00 527
T7W E12 355
R01 E00 266
R01 31K 241
T7W E24 313
T7W E46 310
R01 E00 202
R01 556 246
R01 E13 246
T7W E11 716
T7W E10 255
R01 A41 524
R01 A48 524

Q'ty / set

PLA-A·AA

12, 18, 24, 30

Specification

Remarks

(Drawing No.)

FUNCTIONAL AND STRUCTURAL PARTS
PLA-A12AA
PLA-A18AA
PLA-A24AA
PLA-A30AA

1
2

DRAIN PLUG

14

3

4

5

DRAIN PLUG

13

CAPACITOR

12

TERMINAL BLOCK

11

TERMINAL BLOCK

10

6

TERMINAL BLOCK

9

7

ROOM

8

TEMPERATURE
THERMISTOR

36

FUNCTIONAL AND STRUCTURAL PARTS
PLA-A36AA
PLA-A42AA

1
2

DRAIN PLUG

14

Parts No.

No.

T7W E07 529

1

T7W E00 527

2

T7W E12 355

3

R01 E00 266

4

R01 31K 241

5

T7W E24 313

6

T7W E46 310

7

R01 E00 202

8

R01 556 246

9

R01 E13 246

10
11

T7W E11 716

12

R01 E03 255

13

R01 A41 524

14

R01 A48 524

3

4

5

6

7

Parts Name

DRAIN PAN
DRAIN HOSE
DRAIN PUMP
DRAIN SENSOR
SENSOR HOLDER
INDOOR POWER BOARD
INDOOR CONTROLLER BOARD
ROOM TEMPERATURE THERMISTOR
TERMINAL BLOCK
TERMINAL BLOCK
TERMINAL BLOCK
CAPACITOR
DRAIN PLUG
DRAIN PLUG

Specification

2P (1, 2)
3P (S1,S2, S3)
3P (L1,L2, GR)

7.0+ 440V

Q'ty / set

PLA-A·AA

36, 42

1
1
1
1
1
1
1
1
1
1
1
1
1
1

DRAIN PLUG

13

CAPACITOR

12

TERMINAL BLOCK

11

TERMINAL BLOCK

10

TERMINAL BLOCK

9

ROOM

8

TEMPERATURE
THERMISTOR

Remarks

(Drawing No.)

Wiring

Diagram

Symbol

DP
DS

P.B

I.B
TH1
TB5
TB4
TB2

C

Recom-

mended

Q'ty

37

13

ON/OFF

CENTRALLY CONTROLLED

ERROR CODE

CLOCK

ON OFF

˚C

CHECK

CHECK MODE

FILTER

TEST RUN
FUNCTION

˚C

1Hr.

NOT AVAILABLE

STAND BY
DEFROST

TEMP.

No.

Parts No. Parts Name

Specification

Q'ty / set

Remarks

(Drawing No.)

Wiring

Diagram

Symbol

Recom­mended

Q'ty

1
2
3
4
5
6
7
8

9
10
11

12

RoHS

G
G
G
G
G
G
G
G
G
G
G
G

AIR OUTLET GRILLE
VANE
CORNER PANEL
L.L FILTER
GRILLE ASSY
VANE MOTOR
VANE BUSH
GEAR (VANE)
GEAR
REMOTE CONTROLLER
CABLE ASSY
SCREW ASSY

1
4
4
1
1
4
8
4
4
1
1
1

MV

R.B

T7W E19 003
T7W E09 002
R01 E14 638
R01 E13 500
R01 E44 691
R01 E17 223
R01 E02 063
R01 E03 040
R01 E04 040
T7W E14 713
T7W E04 305
R01 E02 673

PLA-A12/18/24

/30/36/42AA

1

Including H2

RoHS PARTS LIST

PANEL PARTS
PLA-A12AA1 PLA-A18AA1 PLA-A24AA1
PLA-A30AA1 PLA-A36AA1 PLA-A42AA1

1

GEAR

9

GEAR

(VANE)

8

VANE

2

BUSH

7

6

VANE

MOTOR

3

3

3

10

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

4

5

11

38

FUNCTIONAL AND STRUCTURAL PARTS
PLA-A12AA1
PLA-A18AA1
PLA-A24AA1
PLA-A30AA1

1

9 8

7

MOTOR CAP

6

No.

RoHS

R01 E28 114

1

G

R01 09K 097

2

G

T7W H20 480

G

T7W H34 480

3

G

T7W H21 480

G

R01 H05 202

4

G

R01 H15 202

5

G

R01 E03 122

6

G

T7W E05 304

7

G

T7W E27 762

8

G

R01 A51 105

9

G

SPL WASHER

Parts No.

2

3

Q'ty / set

Parts Name

TURBO FAN
SPL WASHER
HEAT EXCHANGER
HEAT EXCHANGER
HEAT EXCHANGER
PIPE TEMPERATURE THERMISTOR
CONDENSER / EVAPORATOR TEMPERATURE THERMISTOR
MOTOR CAP
LEAD ASSY (F/M)
FAN MOTOR
RUBBER MOUNT

Specification

D17D6P70MS

PLA-A·AA1

12 18

1

1

1

1
1

1

1

1

1

1

1

1

1

1

1

1

4

4

24, 30

1
1

1
1
1
1
1
1
4

5

CONDENSER
EVAPORATOR
TEMPERATURE
THERMISTOR

4

PIPE TEMPERATURE
THERMISTOR

Remarks

(Drawing No.)

Wiring

Diagram

Symbol

TH2
TH5

MF

Recom-

mended

Q'ty

39

Q'ty / set

36, 42

Specification

Remarks

(Drawing No.)

No.

Parts No.

Parts Name

Wiring

Diagram

Symbol

Recom-

mended

Q'ty

1

2

3

4

5

6

7

8

9

RoHS

G
G
G
G
G
G
G
G
G

TURBO FAN
SPL WASHER
HEAT EXCHANGER
PIPE TEMPERATURE THERMISTOR

CONDENSER / EVAPORATOR TEMPERATURE THERMISTOR

MOTOR CAP
LEAD ASSY(F/M)
FAN MOTOR
RUBBER MOUNT

1
1
1
1
1
1
1
1
4

TH2
TH5

MF

D17CP110MS

R01 E29 114
R01 09K 097
T7W H22 480
R01 H05 202
R01 H15 202
R01 E03 122
T7W E05 304
T7W E28 762
R01 A51 105

PLA-A·AA

1

FUNCTIONAL AND STRUCTURAL PARTS
PLA-A36AA1

9 8

PLA-A42AA1

1

7

MOTOR CAP

6

SPL WASHER

2

3

5

4

CONDENSER
EVAPORATOR
TEMPERATURE
THERMISTOR

PIPE TEMPERATURE
THERMISTOR

40

FUNCTIONAL AND STRUCTURAL PARTS
PLA-A12AA1
PLA-A18AA1
PLA-A24AA1
PLA-A30AA1

1
2

DRAIN PLUG

14

No.

RoHS

T7W E26 529

1

G

T7W E02 527

2

G

T7W E12 355

3

G

R01 E10 266

4

G

R01 32K 241

5

G

T7W E35 313

6

G

T7W E56 310

7

G

R01 H12 202

8

G

R01 E21 246

9

G

10

G

R01 E18 246

11

G

T7W E41 716

12

G

T7W E15 255

13

G

R01 A00 524

14

G

R01 A01 524

3

4

5

6

7

Parts No.

Parts Name

DRAIN PAN
DRAIN HOSE
DRAIN PUMP
DRAIN SENSOR
SENSOR HOLDER
INDOOR POWER BOARD
INDOOR CONTROLLER BOARD
ROOM TEMPERATURE THERMISTOR
TERMINAL BLOCK
TERMINAL BLOCK
TERMINAL BLOCK
CAPACITOR
DRAIN PLUG
DRAIN PLUG

Specification

2P (1, 2)
3P (S1, S2, S3)
3P (L1, L2, GR)

3.0+ 440V

Q'ty / set

PLA-A·AA

12, 18, 24, 30

1
1
1
1
1
1
1
1
1
1
1
1
1
1

13

12
11
10

9

8

1

(Drawing No.)

DRAIN PLUG

CAPACITOR

TERMINAL BLOCK

TERMINAL BLOCK

TERMINAL BLOCK

ROOM
TEMPERATURE
THERMISTOR

Remarks

Wiring

Diagram

Symbol

DP
DS

P.B

I.B
TH1
TB5
TB4
TB2

C

Recom-

mended

Q'ty

41

No.

Parts No.

Parts Name

Wiring

Diagram

Symbol

Recom-

mended

Q'ty

1
2
3
4
5
6
7
8

9
10
11
12
13
14

RoHS

G
G
G
G
G
G
G
G
G
G
G
G
G
G

DRAIN PAN
DRAIN HOSE
DRAIN PUMP
DRAIN SENSOR
SENSOR HOLDER
INDOOR POWER BOARD
INDOOR CONTROLLER BOARD
ROOM TEMPERATURE THERMISTOR
TERMINAL BLOCK
TERMINAL BLOCK
TERMINAL BLOCK
CAPACITOR
DRAIN PLUG
DRAIN PLUG

1
1
1
1
1
1
1
1
1
1
1
1
1
1

DP
DS

P.B

I.B
TH1
TB5
TB4
TB2

C

2P (1, 2)
3P (S1,S2, S3)
3P (L1,L2, GR)

7.0+ 440V

T7W E28 529
T7W E02 527
T7W E12 355
R01 E10 266
R01 32K 241
T7W E35 313
T7W E56 310
R01 H12 202
R01 E21 246
R01 E18 246
T7W E41 716
R01 E14 255
R01 A00 524
R01 A01 524

Q'ty / set

PLA-A·AA

1

36, 42

Specification

Remarks

(Drawing No.)

FUNCTIONAL AND STRUCTURAL PARTS
PLA-A36AA1
PLA-A42AA1

1
2

DRAIN PLUG

14

3

4

5

DRAIN PLUG

13

CAPACITOR

12

TERMINAL BLOCK

11

TERMINAL BLOCK

10

6

TERMINAL BLOCK

9

7

ROOM

8

TEMPERATURE
THERMISTOR

42

43

TM

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

CCopyright 2006 MITSUBISHI ELECTRIC ENGINEERING CO., LTD.
Distributed in Jun. 2007 No.OC370 REVISED EDITION-B PDF 9
Distributed in Aug. 2006 No.OC370 REVISED EDITION-APDF 9
Distributed in Feb. 2006 No.OC370 PDF 10
Made in Japan

New publication, effective Jun. 2007
Specifications subject to change without notice.