Toshiba RAS-18YAH-A, RAS-18YAH-E, RAS-18YKH-A, RAS-18YKH-E SERVICE MANUAL

SERVICE MANUAL

AIR-CONDITIONER

SPLIT WALL TYPE

FILE NO. A00-0001

SUPPLEMENT

RAS-18YKH-E

RAS-18YKH-A

/

RAS-18YAH-E

/

RAS-18YAH-A

PRINTED IN THAILAND, Apr.,2000

CONTENTS

1. SPECIFICATIONS....................................................................................... 3

2. CONSTRUCTION VIEWS............................................................................ 5

3. WIRING DIA GRAM ..................................................................................... 7

4. SPECIFICATIONS OF ELECTRICAL PARTS ............................................ 8

5. REFRIGERANT CYCLE DIAGRAM............................................................ 9

6. CONTROL BLOCK DIAGRAM ................................................................. 10

7. OPERATION DESCRIPTION .................................................................... 12

8. INSTALLATION PROCEDURE ................................................................. 16

9. TROUBLESHOO TING CHART ................................................................. 20

10. EXPLODED VIEWS AND PARTS LIST .................................................... 37

– 2 –

1. SPECIFICATIONS

Model

Item

Capacity *1 (kW)

Phase

Power source (V)

(Hz)
Power consumption (kW)
Power factor (%)

Running current
Starting current (A)

Moisture removal (lit/h)
Noise

Refrigerant
Refrigerant control

Interconnection pipe

Codensate drain pipe Outer diameter (mm)

INDOOR UNIT

Dimension Width (mm)

Net weight (kg)
Evaporator type
Indoor fan type

Air volume Medium fan (m³/h)

Fan motor output (W)
Air filter

OUTDOOR UNIT

Dimension Width (mm)

Net weight (kg)
Condenser type
Outdoor fan type

Airflow volume (m³/h)
Fan motor output (W)
Compressor
Safety device

Auto louver
Usable outdoor temperature range (°C)

Indoor (A)
Outdoor (A)

Indoor (H/M/L) (dB)
Outdoor (dB)
Name of refrigerant
Rated volume (kg)

Gas side size (mm)
Connection type
Liquid side size (mm)
Connection type
Maximum length (of one way) *2(m)
Maximum height difference
Indoor unit

Outdoor unit

Height (mm)

Depth (mm)

High fan (m³/h)

Low fan (m³/h)

Height (mm)

Depth (mm)

Model
Output (W)

↑
↓

(m)

Specifications are subject to change without notice.

RAS-18YKH-E, RAS-18YAH-E RAS-18YKH-A, RAS-18YAH-A

Cooling Heating Cooling Heating

220–240V 240V

5,0 6,35–6,50 5,0 6,50

Single

220–240V 240V

50

2,03–2,20 2,33–2,52 2,20 2,52

91–81 92–85 81 85

0,28–0,30 0,28–0,30 0,30 0,30

9,82–11,00 11,22–12,10 11,00 12,10

60

2,0

44/41/38

54–56 55–57 56 57

R-22

1,45

Capillary tube

12,7

Flare connection

6,35

Flare connection

15

6

16

RAS-18YKH-E / RAS-18YKH-A

298

1050

180

12

Finned tube

Cross flow fan

750
650
550

31

Polypropylene net filter (Washable)

RAS-18YAH-E RAS-18YAH-A

690
880
310

65

Finned tube

Propeller
220V 240V 240V
3380 3560 3560

65

PH280X3-4MS

2000

Fuse, overload relay

Yes

11 to 43 –10 to 21 11 to 43 –10 to 21

– 3 –

Note : *1

• Capacity is based on the following temperature conditions.

Condition

T emperature

(DB)

Indoor unit inlet air temperature

(WB)

(DB)

Outdoor unit inlet air temperature

(WB)

Notes : *2 CHARGELESS

• No additional refrigerant required.

• This air conditioner accepts a connection piping length of up to 15m and a head of up to 6m.

• There is no need to add the refrigerant as long as the total length of the connection piping is up to 15m.

Cooling Heating

27°C 20°C
19°C —
35°C 7°C
24°C 6°C

JIS C9612-1994

– 4 –

2-1. Indoor Unit

RAS-18YKH-E, RAS-18YKH-A

Deodorizing filter

Air inlet

298

2. CONSTRUCTION VIEWS

Indoor heat exchanger

Dust collecting filter

1050

Air filter

180

Air outlet

261 264 274 251

Drain hose

0,60m

Auxiliary pipe (0,39m)

Flare Ø12,7

Power cord (1,7m)

1040

Hanger

Auxiliary pipe (0,49m)

Detail of installing dimensions of the indoor unit

30

274 264

154020

Hanger

44

Hanger

Flare Ø6,35

990

450

Minimum distance
from ceiling

or more

Front panel

Rear plate

Wireless
remote control

Remote control holder

30

Anchor bolt hole
Anchor bolt hole

55 16

112.8 136

59.6 5

Ø8 ~ Ø10

Ø6

298

248

304010

Minimum distance
from wall

80 or more

Ø65

Piping hole

123

Center line

1050

– 5 –

Installation plate

Minimum distance
from wall

130 or more

123402402

47

Ø65

Piping hole

2-2. Outdoor Unit

RAS-18YAH-E, RAS-18YAH-A

A

340

63,8

4–Ø12 x 18 hole
(for Ø8–Ø10 anchor bolt)

690

120

600

880

Ø25 Drain outlet

140

Handle

74

88

68 52

12

23

310

340 (pitch)

364

Electric
Parts cover

Liquid side
(Flare Ø6,35)

Gas side
(Flare Ø15,88)

Service port

12

Handle

Mounting dimension of anchor bolt

600

100 or more

Air inlet

340

100 or more

Air outlet

Air inlet

600 or more

600 or more

4 x Ø12 x 18 for Ø8–Ø10 anchor bolt

– 6 –

Detail Drawing

A

340

600

50

27

Ø12 x 18 hole

3. WIRING DIAGRAM

CN16

COLOR

IDENTIFICATION

BRW : BROWN

RED : RED
WHI : WHITE

YEL : YELLOW

BLU : BLUE

BLK : BLACK

GRY : GRAY

PNK : PINK

ORN : ORANGE

GRN & YEL: GREEN &

ORANGE

Indoor terminal block
Outdoor terminal block

Power supply
18YAH-E : 220–240V ~, 50Hz
18YAH-A : 240V ~, 50Hz

L

N

Ferrite core

BLK

RED

GRN & YEL

BLK

RED

Switch parts

1 2 3

WHI

1
1 2 3

CN15

F01 Fuse

CN03

1
1

BLK WHI

1

BLU

2 3

T5A

250V

3 5

2

BLU

GRN

&

YEL

53

Grand

terminal

321

Chassis

CN25

TNR

R106

RED

3

GRN & YEL

Louver

Indication parts

4 5 6 7 8 9321
4 5 6 7 8 9321

WHI

BRW

BRW

BRW
4 5 6 7 8 9321

4 5 6 7 8 9321

BRW

C28

BRW

BRW

L01

Filter

BRW

BRW

C27

motor

CR01

TRIAC D04

MAIN P.C. BOARD (MCC-1293)

CN17

1 2 3
1 2 3

WHI

RED
1 2 3
1 2 3

Infrared rays
receive parts

Transformer

BLK

PJ18

Thermal fuse

BLU
YEL

RED

WHI
BLK
BLK

WHI
RED
GRY

1 1
3 3
1 1
3 3
1 1
3 3
5 5
7 7
9 9

CN26

ORN

77˚C

2

21
21

ORN

CN06

CN05

TNR R74

CN01

21
21

BLK

BLK

Thetmo.

sensor

MAIN P.C. BOARD (MCC-1275)

T5A, 250V AC

PNK

BLU

5 4 3 2 1

6
6 5 4 3 2 1

TNR R98

TH01

PTH

21
21

BLK

BLK

Heat exchanger

sensor

DSA

YEL

CN10CN24

RED

ORN

CN13

C26
Running
capacity

CN07

CN12

CN01

CN22CN05CN04

1 2
1 2

WHI

1 2

Buzzer

parts

TNR
R73

BRW

BLU

5
3
1

2

CN30

Thermal fuse

164˚C

YEL

11

GRY

22

BRW

33

WHI

5

BLK

3

RED

1

WHI

33

RED

1

CN32

GRY

33

BLU

11

CN11

CN11

T01

313

1

Fan motor

IC

MCC-629

1 1
2
3 3

1 1
2
3 3

Transformer
1

2
3131
CN33

Discharge
temperature
sensor (TD)

BLK
BLK

Heat

exchanger

sensor (TE)

BLK
BLK

Crank case
heater

1 1
2 2

RED
Fuse

BLK

3A

Fuse

3A

BLK

Capacitor Capacitor

RED

WHI

PNK

Compressor

Magnetic

relay

21

5L3

3L2

22

6T3

4T2

RED

RED

BLK BLK

WHI

A1

1L1

52C

A2

2T1

Fan motor

BLU

YEL
BLK
BLK

Coil for

4-way valve

BLU

1 1
3 3

5

1 1
3 3
1 1
3 3
1 1

– 7 –

3

CN04

CN11

CN02

CN03

CR11

CR12

RY07

RY05

TNR R96

IC07

4. SPECIFICATIONS OF ELECTRICAL PARTS

4-1. Indoor Unit

RAS-18YKH-E, RAS-18YKH-A

No. Parts name Type Specifications

Output (Rated) 31W, 2poles, DC35V, 19W

1 Fan motor (for indoor) AFP-220-31-4B

2 Thermo. sensor (TA-sensor) (microprocessor) 10kΩ at 25°C
3 Transformer (T01) TTZ MCC-629
4 Microcomputer TMP87CK40AN
5 Heat exchanger sensor (microprocessor) 10kΩ at 25°C

(TC-sensor)
6 Line filter (L01) 25mH, AC 0,7A
7 Diode (DB01) KBP06M
8 Capacitor (C01) ECAIEHG222E 220µF, 25V
9 Fuse (F01) MT3 T5A, 250V

10 Varistor (R98, R106) 15G431K 430V
11 PTH (TH01) 82Ω
12 Louver motor MP35EA7 Output (Rated) 2W, 10poles, 1phase DC12V

Winding resistance (Ω)
(at 20°C)

Red-Black White-Black

267,8 147,7

4-2. Outdoor Unit

RAS-18YAH-E, RAS-18YAH-A

No. Parts name Type Specifications

Output (Rated) 2000W, 2poles, 1phase, 220–240V, 50Hz

1 Compressor PH280X3-4MS

2 Fan motor (for outdoor) MMF-230-65C

3 Running capacitor (for fan motor) SK45FMP AC 450V, 3,5µF
4 Running capacitor SK42CMP45U1 AC 420V, 45µF

(for compressor)
5 Solenoid coil (for 4-way valve) LB60012 AC 200/240V
6 Thermo. sensor TE, TD 10kΩ at 25°C
7 Case heater 240V, 28W
8 Magnetic switch FC2S 3a1b
9 Transformer FT67 220–240V

10 Microcomputer TMP470840
11 Varistor (R73, 74, 86) 15G471K 470V
12 Fuse (F01) MT3 T5A, 250V

Winding resistance (Ω)
(at 20°C)

Output (Rated) 65W, 6poles, 1phase, 220–240V, 50Hz
Winding resistance (Ω)

(at 20°C)

Red-Black White-Black

1,35 2,68

Red-Black White-Black

71,2 139,0

– 8 –

5. REFRIGERANT CYCLE DIAGRAM

INDOOR UNIT A

T1

Cooling

0,39m
(Connecting pipe)
Ø12,7

O.D. : 12,7mm O.D. : 6,35mm

Cooling

Heating

Heating

P

Packed valve
(Ø12,7)
Gas container connection (Reinstall etc.)

Heating

4-way valve

Cooling

Accumulator

Compressor
PH280X3-4MS

Indoor heat

exchanger

Cross flow fan

Packed valve

(Ø6,35)

Liquid tank
550cc

Capillary tube
Ø1,7 x 600

(Note)
Maximum pipe length is 15m
Maximum pipe head is 6m

0,49m
(Connecting pipe)
Ø6,35

Capillary tube
Ø1,2 x 700

Outdoor heat exchanger

Propeller fan

Cooling
Heating

Standard pressure Surface temp. of heat

50Hz

Standard 21,0 53,0 High

Heating High temperature*1 20,5 to 25,5 52,0 to 61,0 Low

Low temperature 17,0 45,0 High
Standard 3,0 9,0 High

Cooling High temperature 3,5 11,0 High

Low temperature 2,5 1,5 Low

P exchanger interchanging Fan speed

(kg/cm²G) pipe T1 (°C) (indoor)

18YAH-E, A 18YKH-E, A

OUTDOOR UNIT

Mark ( ) means check points of Gas Leak

Note :

• Measure the heat exchanger temperature at the center of U-bend. (By means of TC sensor.)

*1 • During heating overload, the high temperature limit control operation is included.

Refrigerant
R-22 1,45kg

Ambient temp.

conditions DB/WB

(°C)

Indoor Outdoor

20/– 7/6
27/– 21/15

20/– –10/–10
27/19 35/24
32/23 43/26
21/15 21/15

– 9 –

6-1. Indoor Unit

– 10 –

Heat Exchanger Sensor

Temperature Sensor

Infrared Rays Signal Receiver

CLOCK FREQUENCY 36,864kHz

Remote Control

Operation (START/STOP)

Operation Mode Selection

AUTO, COOL, DRY, FAN ONLY

Thermo. Setting

Fan Speed Selection

Infrared

Rays

Indoor Unit Control Panel

Initializing Circuit

Clock Frequency

Oscillator Circuit

8MHz

Power Supply

Circuit

M.C.U

Functions

• Louver Control

• 3-minute Delay at Restart for Compressor

• Motor Revolution Control

• Processing
(Temperature Processing)

• Timer

• Serial Signal Communication

Operation

Display

Timer

Display

6. CONTROL BLOCK DIAGRAM

ECONO.

Sign Display

PRE DEF.

Sign Display

ON TIMER Setting

OFF TIMER Setting

Louver AUTO Swing

Louver Direction Setting

From Outdoor Unit

ECONO.

Photo Triac

Noise Filter

Indoor

Fan Motor

Louver ON/OFF Signal

Louver Driver

Serial Signal Transmitter/Receiver

Transformer Serial Signal Communication (outdoor unit)

Louver

Motor

6-2. Outdoor Unit

– 11 –

TD

Discharge

Temperature

Sensor

TE

Heat

Exchanger

Sensor

Serial Signal

Communication

(Indoor Unit)

Serial Signal

Transmitter/

Receiver

C.P.U

4-Way Valve

ON/OFF Signal

Compressor

ON/OFF Signal

Outdoor Fan

ON/OFF Signal

• Compressor Control

• 4-Way Valve Control

• Outdoor Fan Control

• Defrost Operation

• Serial Signal Communication

Relay
RY05

Relay

Driver

Relay
RY07

Photo

Coupler

Initializing Circuit

Clock frequency
Oscillator Circuit

Power Supply Circuit

Triac

6MHz

4-Way

Valve

Magnetic

Switch

Outdoor

Fan Motor

Power
Supply

(for Indoor Unit)

Transformer

Compressor

RAS-18YAH-E : AC220–240V, 50Hz
RAS-18YAH-A : AC240V, 50Hz

7. OPERATION DESCRIPTION

7-1. FAN ONLY Operation

(MODE of the remote control : FAN ONLY)

(1) Fan speed setting

1) When the FAN is set to A UTO, the indoor fan
motor operates as shown in Fig 7-1-1.

2) When the FAN is set to LOW, MED, or HIGH,
the indoor fan motor operates with a constant
in volume as listed in Table 7-1-1.

28
27

Room temp.

26
25
24

Fig. 7-1-1 A uto setting of air volume

T a ble 7-1-1 Manual setting of FAN SPEED

Indication of HIGH Air volume

F AN SPEED (m3/h)

LOW 550
MED 650

HIGH 750

(2) Once the setting is made, the operation mode is

memorized in the microcomputer so that the
same operation can be effected thereafter
simply by pushing the START/STOP button.

HIGH

MED
LOW(+)

LOW

LOW

7-2. COOL Operation

(MODE of the remote control : COOL)

(1) Compressor, 4-way v alve, outdoor fan and

operation display are controlled as shown in Fig.
7-2-1.

+1

Set temp.)

(Room temp. –

Set

0

temp.

Fig. 7-2-1

ON

OFF

Compressor

(2) A cool operation is carried out when the indoor

microcomputer sends the operation signal to the
outdoor microcomputer.

1) When the FAN is set to A UTO, the indoor fan
motor operates as shown in Fig 7-2-2.

2) When the FAN is set to LOW, MED, or HIGH,
the indoor fan motor operates with a constant
in volume as listed in Table 7-1-1.

AUTO

+1,5
+1,0
+0,5

+0

(Room temp. – Set temp.)

Set

–0,5

temp.

RY01 OFF

HIGH

MED (+)

MED

LOW (+)

LOW

Fig. 7-2-2

ON

OFFOFFON ON

4-way valve

FAN

Manual

According
to the set

position

Outdoor fan

Common relay

display

OPERATION

– 12 –

(3) Once the setting is made, the operation mode is

memorized in the microcomputer so that the
same operation can be effected thereafter
simply by pushing the START/STOP button.

7-2-1. Louver Control

(1) By pushing the SET button of the remote control

during the operation, the louver can be set to the
desired position.

And the louver position is stored in the micro­computer, the louv ers will be set to the position
automatically at the next operation.

(2) When the AUT O b utton is pushed, the louv er

vertically swings within range of 25deg.

7-3. HEAT Operation

(MODE of the remote control : HEAT)

(1) Compressor, 4-wa y valv e , outdoor fan and

operation display are controlled as shown in Fig.
7-3-1.

0

OFF

ON

ON ON

7-3-1. Louver Control

(1) By pushing the SET button of the remote control

during the operation, the louver can be set to the
desired position.

(2) When the AUT O b utton is pushed, the louv er

vertically swings within range of 25deg.
And the louver position is stored in the micro-

computer, and at the ne xt operation, the louvers
will be set to the stored position automatically at
the next operation.

OFF

7-3-2. Cool Airflow Control

–1

(Room temp. – Set temp.)

ON

Compressor

Common relay

ON

4-way valve

Outdoor fan

Fig. 7-3-1

(2) A heat operation is carried out when the indoor

microcomputer sends the operation signal to the
outdoor microcomputer. The indoor f an motor
operates as shown in Fig. 7-3-2, when the FAN
is set to AUTO.

The motor operates with a constant air volume
as listed in Table 7-1-1, when the FAN is set to
LOW, MED, or HIGH.

Set
temp.

RY01 OFF

10,5

0
–0,5
–1,0
–1,5

AUTO

LOW

LOW (+)

MED

MED (+)

HIGH

FAN

Manual

According
to the set
position

display

OPERATION

(1) If the indoor heat-exchanger temperature

detected by the indoor heat-exchanger sensor is
16°C or below , the indoor fan stops and if the
temperature rises to 26°C or above, the f an is
restarted.

Details are in 7-8.

(Room temp. – Set temp.)

Fig. 7-3-2

(3) Once the setting is made, the operation mode is

memorized in the microcomputer so that the
same operation can be effected thereafter
simply by pushing the START/STOP button.

– 13 –

7-4. A UTO Operation

(MODE of the remote control : AUTO)

(1) One of the 3 modes, Cooling, Fan only and

Heating is selected according to room tempera­ture at which operation is to start, as shown in
Fig. 7-4-1. The Fan mode will continue until
room temperature reaches a level at which
another mode is selected.

7-4-1. Temporary Auto

When the TEMPORARY button is pushed, the set
temperature is fixed at 24°C and controlled in
accordance with the chart shown in Fig. 7-4-1.

Cooling mode

+3

Heating mode

–3

(The same cooling mode as the room temperature control is set at set temp. –3˚C)

(The same heating mode as the room temperature control is set at set temp. +3˚C)

(Room temp. – Set temp.)

7-5. ECONO. Mode

When the ECONO. button is pushed, during COOL,
HEAT and AUTO operation, the OPERATION display
is turned off and the ECONO. display is lit and the
indoor unit operates quietly and mildly with control­ling airflow .

7-5-1. Cooling

(1) In the ECONO. mode, the set temp. by the

remote control is changed automatically as
shown in Fig. 7-5-1.

(2) Fan speed → LOW

(˚C)

Set temp.
is changed

+2

Set temp.
is changed

+1

Fig. 7-4-1

7-5-2. Heating

(1) In the ECONO. mode, the set temp. by the

remote control is changed automatically as
shown in Fig. 7-5-2.

(2) Fan speed → LOW

ECONO. button
is pushed

1H 2H TIME0H

Set temp.

-1
Set temp.

is changed

-2

Set temp.
is changed

(˚C)

Fig. 7-5-2

Set temp.

1H 2H TIME0H

ECONO. button
is pushed

Fig. 7-5-1

– 14 –

According to the

set position

Indoor fan speed

30
26
20
16

Heat exchanger
temperature

(˚C)

OFF

L (Low)

7-6. High-T emperature Limit Control

(Heating Operation)

7-8. Cool Airflow Prevention Control

(Heating Operation)

The microprocessor detects the indoor heat ex­changer temperature so as to prevent e xceeding the
condensate pressure.

Control is performed as shown in Fig. 7-6-1.

Heat exchanger
temperature

(˚C)

60

*

1

54

52

*

1 ····· Only outdoor fan is turned off.

Compressor,

Outdoor fan

OFF

ON

Fig. 7-6-1

7-7. Low-Temperature Limit Control

(Cooling Operation)

The microprocessor detects the indoor heat ex­changer temperature so as to prevent freezing up
the indoor heat exchanger .

Control is performed as shown in Fig. 7-7-1.

Heat exchanger
temperature

(˚C)

12

2

Compressor

Less than 2˚C continues

Outdoor fan

ON

for 6 minutes

OFF

(1) During the heating operation, the indoor fan

speed is controlled automatically in accordance
with the indoor heat exchanger temperature to
prevent b lo wing the cool air.

Control is performed as shown in Fig. 7-8-1.

Fig. 7-8-1

(2) As soon as the defrost operation starts, the

indoor fan stops.

7-9. Defrost Operation

During heat operation, if the temperature (Evaporat­ing temperature) detected by the outdoor heat
exchange sensor (TE :Defrost) low ers b y the set
degree less than the temperature detected at start
time, the operation enters the defrost operation. In
this time, the 4-wa y v alve relay and the outdoor fan
are turned off. The indoor fan is turned off by the
cool air blow-out pre v enting control of the indoor
microcomputer at the indoor side, and "PRE.-DEF."
on the remote control goes on.

The defrost operation is automatically reset to the
normal operation when the temperature detected by
the above-mentioned TE sensor rises up to the set
value, or when Max. 12 minutes of the operation
time has passed.

Fig. 7-7-1

– 15 –

8. INSTALLATION PROCEDURE

8-1. Safety Cautions

For general public use

Power supply cord of parts of appliance for outdoor use shall be more than polychloroprene
sheathed flexible cord (design H05 RN-F), or cord designation 245 IEC 57.

CAUTION

This appliance must be connected to the mains by means of a circuit breaker or a switch with a
contact separation of at least 3 mm.
If this is not possible, a power supply plug with earth must be used. This plug must be easily
accessible after installation. The plug must be disconnected from the power supply socket in order
to disconnect the appliance completely from the mains.

REQUIREMENT OF REPORT TO THE LOCAL POWER SUPPLIER

Please make sure certainly that the installation of this air conditioner will be reported to the local
power supplier before installation.
If you have any obscure problems (or if the power supplier does not accept the installation) of this
appliance, service agency will take adequate countermeasures.

To Disconnect the Appliance from the Mains Supply.

8-2. Installation Diagram of Indoor and Outdoor Units

Anchor bolt arrangement of
outdoor unit

340 mm

• Secure the outdoor unit with the
anchor bolts if the unit is likely to
be exposed to a strong wind.

• Use Ø8 or Ø10 anchor bolts.

• If it is necessary to drain the
defrost water from the outdoor
unit, base pan attach the
drain nipple to the outdoor unit
before installing it.
The drain outlet is located as
shown above.

64 mm

600 mm

120 mm

Air outlet

Air intlet

Drain outlet

9

Air filters
(for both sides)

Mounting
screw

80mm or more

Clip anchor
(local part)

6

44mm or more

4

Pan head
wood screws

Installation

1

plate

130mm

or more

During piping installation

Wall

Insert the remote control holder cushion
between the indoor unit and wall, and lift
the indoor unit to make work easier.

Do not allow the drain hose
to get slack.

Cut the piping hole
sloped slightly

Make sure to run the drain hose sloped
downward.

The auxiliary piping can be
connected to the left, rear or down.

– 16 –

DANGER

• FOR USE BY QUALIFIED PERSONS ONLY.

• TURN OFF MAIN POWER SUPPLY BEFORE ATTEMPTING ANY ELECTRICAL WORK. MAKE
SURE ALL POWER SWITCHES ARE OFF. FAILURE TO DO SO MAY CAUSE ELECTRIC
SHOCK.

• CONNECT THE CONNECTING CABLE CORRECTLY. IF THE CONNECTING CABLE IS
CONNECTED BY WRONG WAY, ELECTRIC PARTS MAY BE DAMAGED.

• CHECK THE EARTH WIRE IS NOT BROKEN OR DISCONNECTED BEFORE INSTALLATION.

• DO NOT INST ALL NEAR CONCENTRATIONS OF COMBUSTIBLE GAS OR GAS VAPORS.
FAILURE T O FOLLOW THIS INSTRUCTION CAN RESULT IN FIRE OR EXPLOSION.

• TO PREVENT OVERHEATING THE INDOOR UNIT AND CAUSING A FIRE HAZARD, PLACE
THE UNIT WELL AWAY (MORE THAN 2M.) FROM HEAT SOURCES SUCH AS RADIATORS,
HEA T REGISTORS, FURNACE, STO V ES , ETC .

WARNING

• Never modify this unit by removing any of the safety guards or by by-passing any of the safety
interlock switches.

• Do not install in a place which cannot bear the weight of the unit.
Personal injury and property damage can result if the unit falls.

• Before doing the electrical work, attach an approved plug to the power supply cord.
And make sure the equipment to be earthed.

• Appliance shall be installed in accordance with national wiring regulations.

CAUTION

• Exposure of unit to water or other moisture before installation will result in an electrical short.
Do not store in a wet basement or expose to rain or water.

• After unpacking the unit, examine it carefully for possible damage.
If you detect any damage, do not install the unit. Contact y our T oshiba dealer immediately.

• Do not install in a place that can increase the vibration of the unit. Do not install in a place that can
amplify the noise level of the unit or where noise and discharged air might disturb user’s neighbors.

• To av oid personal injury, be careful when handling parts with sharp edges.

• Please read the installation manual carefully before installing the unit. It contains further
important instructions for proper installation.

Deodorizing

7

filter

8

Before installing the wireless remote control

Wireless remote control

• With the remote control
cover opened, load the
supplied batteries correctly,
observing their polarity.

2

5

Batteries

Cover

100mm
or more

8-2-1. Optional Installation Parts

Part code Parts name Q’ty

Refrigerant piping

A Liquid : Ø6,35 Each one

Gas side : Ø12,7
Pipe insulating material

B

(Polyethylene foam, 6mm thick)

C Putty, PVC tapes Each one

Purifying
filter

600mm or more

1

Remote control

3

holder

2

Wireless remote
control

Vinyl tape
Apply after carrying
out a drainage test.

Saddle

100mm or more

Extention drain hose
(Option : RB-821SW)

600mm or more

Electric
parts
cover

600mm

or more

Loop the connective cable
(about 100 mm in diameter and 300 – 350 mm long).

Rear

Down

Rear left

Insulation of refrigerant pipes insulates
the pipes separately, not together.

6 mm thick heat resisting
polyethylene foam

Left

Drainage

Ø25

Drain

9

nipple

Bottom
plate

• Install the provided drain nipple in the
hole of the bottom plate of the outdoor
unit. (See figure at left.)

• Perform proper drainage processing
using a separately sold or market
available drain hose.
(16 mm inner diameter.)

• Do not use an ordinary hose available
at the market, since it tend to get flat,
resulting in a clog of drain water.

Separately sold or
market available
drain hose.

– 17 –

Concrete wall Concrete wall

Installation
plate

Hole in anchor

Bolt

Hole in anchor Installation plate

Nut with threaded
hole 8 mm dia.

Less than 15 mm

(6) Screws

(6)

(7)

(7)

(1) (2) (1) (2) (1) (2) Screw caps and screws

(5)

(3) (4)

(3) (4)

Front panel

Rear plate

Rear plate
bushing

Electrical component
box cover

Screws

Cord clamp

Wiring cover

Screw

8-3. Indoor Unit

8-3-1. Installation Place

• A place which provides the spaces around the
indoor unit as shown in the above diagram.

• A place where there is no obstacle near the air inlet
and outlet.

• A place which allows an easy installation of the
piping to the outdoor unit.

• A place which allows the front panel to be opened.

CAUTION

• Direct sunlight to the indoor unit wireless

receiver should be avoided.

• The microprocessor in the indoor unit should

not be too close to r-f noise sources.
(For details, see the owner's manual.)

Remote control

• A place where there are no obstacles such as a
curtain that may block the signal from the indoor
unit.

• Do not install the remote control in a place exposed
to direct sunlight or close to a heating source, such
as a stove.

• Keep the remote control at least 1 m apart from the
nearest TV set or stereo equipment.
(This is necessary to prevent image disturbances or
noise interference.)

• The location of the remote control should be
determined as shown below.

(Side view)

Indoor unit

75˚

Reception
range

8-3-2. Installation Parts

Part with an asterisk (*) is packaged with outdoor unit.

Part

Name of parts (Q'ty)

No.

1

Installation plate x 1

2

Wireless remote control x 1

3

Remote control holder x 1

4

Pan head wood screw
Ø3,1 x 16

5

Batteries x 2

x 2

7m

Remote

control

Fig. 8-3-1

(Top view)

Indoor unit

*

Part

Reception
range

: Axial distance

No.

6

7

8

9

Others

5m

5m

45˚

45˚

7m

*

Remote
control

Name of parts (Q'ty)

Mounting screw Ø4x 25

Deodorizing filter x 1

Purifying filter x 1

Drain nipple

x 1

*

Name

Owner’s manual

Installation manual

x 8

8-3-3. Cutting a Hole and Mounting

Installation Plate

Cutting a hole

Hooking
section

Center of pipe hole is located
on the line indicated by the
arrow and 100 mm apart from
the pipe hole center line.

100mm

Fig. 8-3-2

Refrigerant pipe hole
Ø65mm

47mm

Indoor unit outline

When installing the refrigerant pipes from the rear.
Determine the pipe hole position using the installation

plate, and drill the pipe hole Ø65 mm slightly downward.

NOTE

When using the drill to pierce the wall that contains a
metal lath, wire lath or metal plate, be sure to use a
pipe hole brim ring sold separately.

Mounting the installation plate

For installation of the indoor unit, use the paper
pattern on the back.

1 Installation plate

80mm
or more

40mm

100mm

Refrigerant pipe hole
Ø65mm

When the installation plate is directly
mounted on the wall

1. Securely fit the installation plate onto the wall by
screwing it in the upper and lower parts to hook up
the indoor unit.

2. To mount the installation
plate on a concrete wall with
anchor bolts, utilize the
anchor bolt holes as
illustrated in the above figure.

3. Install the installation plate
horizontally in the wall.

450mm

Anchor

Thread

Fig. 8-3-3

44mm
or more

bolt hole

100mm

Weight

Indoor unit
outline

40mm

21mm
4mm
130mm

or more

47mm

Refrigerant
pipe hole
Ø65mm

Installation plate
(Keep horizontal direction)

Fig. 8-3-4

CAUTION

Failure to firmly install the unit may result in
personal injury and property damage if the unit falls.

1. Adjust the lateral position of the installation plate
without changing the height, so that each screw hole
in the plate comes in the center of a pillar or stud.

2. Make pilot holes with a bit to prevent the studs
from cracking, and then drive the screws into the
holes and tighten.

CAUTION

When installing the installation plate with
mounting screw, do not use the anchor bolt hole.
Otherwise the unit may fall down and result in
personal injury and property damage.

• In the case of a reinforced concrete wall

(1) In the selected area on the reinforced concrete wall,

bore holes at intervals of 450 mm, and drive
clip anchors or hole in anchors into them.

(2) Attach the installation plate to the wall by

screwing bolts or nuts into the anchors.
However, in the case where hole in

anchors are used, the depth of the
holes should be adjusted so that the nut­heads extend no more than 15 mm. Fig. 8-3-5

• There may be a wire conduit embedded in the wall.
Confirm on the blue prints or ask the builder.

• Install the installation plate using 4 to 8 pieces of
mounting screw securing four corners with screws.

• Make sure of the proper installation of the
installation plate before mounting the indoor unit.

Anchor
bolt

Projection
15mm
or less

Fig. 8-3-6

• In the case of the pipe on the back

Using the pattern, position the pipe hole, and bore the
hole slightly downward.

8-3-4. Electrical Work

Important items of indoor unit wiring

1. For electrical works the wiring and cables must be
performed in compliance with national wiring
standard or regulation. If incorrect and incomplete
wiring is carried out, it will cause an electrical fire
or electrical shock.

2. Do not use the inter-connecting cable.
Never execute the connection of electrical wiring
with other method than the approved one.
(exp. use the terminal block etc.)

3. Prepare the interior power supply cord capacity
sufficient for starting and usage current of air
conditioner.

4. Connect the connecting cable to the terminal as
identified with their respective matched numbers
on the terminal block of outdoor unit.

5. Fix the cable securely with the cord clamps to the
specified position.

6. Do not damage or scratch the conductive core &
inner insulator of power supply and inter
connecting cables when peeling them.

7. Do not deform or smash the surface of the cables.
Do not press or fix the cord and cables firmly with
staples, etc.

How to connect the cable

1. Remove the side panel. (2 screws)

2. Remove the electric parts cover and cord clamp.

3. Insert the connecting cable fully into the terminal
block and secure it by screw tightly.

Tightening torque : 1,2 N•m (0,12 kgf•m)

4. Secure the con­necting cable with
the cord clamp.

5. Fix the electric
parts cover and
side panel.

How to open the screw cap

• Place your finger on the
lower part and push up to
open the screw cap.

Fig. 8-3-7

CAUTION

• Be sure to refer the wiring system diagram
labeled inside the side panel.

• Check local electrical codes and also any
specific wiring instruction or limitation.

How to remove the front panel

Fig. 8-3-8

(1) Open the screw caps and remove three front

panel fixing screws.
(2) Put the screw caps back as they were.
(3) Press the part saying “PUSH” on the air inlet grille

to open the air inlet grille.

Remove three black front panel fixing screws.
(4) Close the air inlet grille.
(5) Manually open the vertical air flow louver directly

below.
(6) Open the front panel lower portion until it comes in

contact with the vertical air flow louver. Lift up the

front panel upper portion in a forward diagonal

direction to unhook the clicks inside the front

panel upper portion.
(7) After unhooking the nails inside the main unit

upper portion, rotate the front panel upper portion

towards you to remove the front panel from the

unit body.

Fig. 8-3-9

Stripping length of connecting cable

220 mm

10 mm

3

2
1

50 mm

60 mm

Fig. 8-3-10

NOTE

• Use standard wire only

• Wire type : More than H05 RN-F (1,3 mm² or more)

• Inser t the connecting cable fully into the terminal

block and secure it by screw tightly.

• Tightening torque : 1,2 N•m (12 kgf•cm)

• Secure the connecting cable with the cord clamp.

• Fix the wiring cover, rear plate bushing and front

panel on the indoor unit.

– 18 –

TEMPORARY

REMOTE CONTROL

AUTO
TEST RUN
(COOL)

Cord clamp

Grounding
wire

21

Terminal block
Connecting

cable

Wiring cover

Screws

Screw

Fig. 8-3-11

8-3-5. Piping and Drain Hose Installation

Left-hand connection with piping

• After scribing slits of the rear
panel by a knife or a marking­off pin, cut them by a pair
of nippers or the like.

Slit (rear panel)

Fig. 8-3-12

Bend the connecting pipe so that it is laid within 52
mm above the wall surface. If the connecting pipe is
laid exceeding 52 mm above the wall surface, the
indoor unit may unstably be set on the wall.

When bending the connecting pipe, make sure to use
spring bender so as not to crush the pipe.

Bend the connecting pipe within a radius of 40 mm.

NOTE

If the pipe is bent incorrectly, the indoor unit would be
unstably set on the wall and the air conditioner might
be raised.

1. When the piping runs to the left, remove the left

side body bushing of the rear panel. You may need
the body bushing when you relocate the unit, so
be sure to make customer keep it in a safe place.

2. After passing the connecting pipe through the pipe

hole, connect the connecting pipe to the auxiliary
pipes and wrap facing tape around them.

Outward form of indoor unit

R 40mm (Use polisin (polyethylene core)
or the like for bending pipe.)

52 mm

80˚

Use the handle of screwdriver,etc.

Fig. 8-3-13

Underside connection with piping

1. Cut out the knock-out piece from the right below of
the rear plate with a knife, etc. Smooth the cut
edges.

Pipe holder Rear plate

Slit part

Pipe holder

Fig. 8-3-14

CAUTION

• Bind the auxiliary pipes (two) and connecting
cable with facing tape tightly. In case of leftward
piping and rear-leftward piping, bind the
auxiliary pipes (two) only with facing tape.

Fig. 8-3-15

1

2

Indoor unit

Space for pipes

Connecting
cable

Hook here

1

Hook here

Fig. 8-3-16

Fig. 8-3-17

Installation
plate

Wall

Drain
guide

Auxiliary
pipes

Installation
plate

• Carefully arrange pipes so that any pipe does
not stick out of the rear plate of the indoor unit.

• Carefully connect the auxiliary pipes and
connecting pipes to each other and cut off the
insulating tape wound on the connecting pipe to
avoid double-taping at the joint, moreover, seal
the joint with the vinyl tape, etc.

• Since dewing results in a machine trouble,
make sure to insulate both the connecting
pipes. (Use polyethylene foam as insulating
material.)

• When bending a pipe, carefully do it not to
crush it.

8-3-6. Indoor Unit Fixing

1. Pass the pipe through the hole in the wall, and
hook the indoor unit on the installation plate at the
upper hooks.

2. Swing the indoor unit to right and left to confirm
that it is firmly hooked up on the installation plate.

3. While pushing the indoor unit onto the wall by the
lower part, hook it up on the installation plate by
the lower part.
Pull the indoor unit
toward you by the
lower part to confirm
that it is firmly
hooked up on the
installation plate.

This air conditioner has the
structure designed to drain
water collected from dew,
which forms on the back of the
indoor unit, to the drain pan.

Therefore, do not store the
power cord and other parts
at a height above the drain
guide.

8-3-7. Drainage

1. Run the drain hose sloping downwards.

NOTE

• Hole should be made at a slight downward slant to
the outdoor side.

Do not rise the drain hose.

50 mm
or more

2. Put water in the drain pan and make sure that the water
is drained out of doors.

3. When connecting extension drain hose, insulate the
connecting part of extension drain hose with shield
pipe.

Drain hose

Do not form the drain hose
into the waved shape.

Do not put the
drain hose end
into water.

Fig. 8-3-18

Shield pipe

Inside the room

Do not put the drain
hose end in the
drainage ditch.

Extension drain hose

Fig. 8-3-19

CAUTION

Arrange the drain pipe for proper drainage from the
unit. Improper drainage can result in dew-dropping.

How to install the front panel on the indoor unit

Install the front panel through the opposite order of “How
to remove the front panel”.

When the panel is removed and mounted again, take the
following action : After fastening the 6 screws, be sure to
hook the inside clicks
shown in the diagram, right gap is between the front panel
and the rear plate.

• If cooling (dr y) operation is made without pushing the air

outlet, dew can be deposited on the front panel surface.
In addition, a gap between the front panel and the body

will become wider, spoiling the appearance.

8-3-8. Gas Leak Test

• Check the flare nut connections, valve stem cap

connections and service
cap connections for gas
leak with a leak detector
or soap water.

Fig. 8-3-21

, , and  of the front panel

Push Push Push

3

Fig. 8-3-20

Flare nut
connections
(Outdoor unit)

1

Electric parts
cover

2

Valve stem cap connection

D

B

C

Flare nut
connections
(indoor unit)

Valve stem
cap connection

A

Service cap
connection

8-3-9. Check and Test Operation

¨ 1. Check the unit is firmly hooked up on the

installation plate.

¨ 2. Check the connecting pipes tightened

securely.
Confirm that there is no gas leakage.

¨ 3. Confirm that all connecting cables are

secured and correct.

¨ 4. Check the pipe insulation.
¨ 5. Check the drainage.
¨ 6. Connection of the grounding wire.
¨ 7. To switch the TEST RUN (COOL) mode,

turn the switch on.

TEMPORARY

REMOTE CONTROL

AUTO

TEST RUN
(COOL)

Fig. 8-3-22

Make sure to return the TEMPORARY switch
to REMOTE CONTROL.

Three-minutes protection feature

A protection feature prevents the air
conditioner from being active for about 3
minuets when it is restarted immediately
after operation.

¨ 8. Operate the unit at cooling operation

mode for fifteen minutes or more.
Measure the temperature of the intake

and discharge air. Ensure the difference
between the intake temperature and the
discharge one is more than 8°C.

NOTE: Three-minutes protection feature

A protection feature prevents the air
conditioner from being activated for
about 3 minutes when it is restarted
immediately after operation.

¨ 9. Check the remote control operation when

it is at fixed position.

When finished the check and test operation,
make sure to return the TEMPORARY switch
to REMOTE CONTROL.

¨ 10. Explain to the customer on the correct

usage of air conditioner with simple
layman’s terms.

8-4. Outdoor Unit

8-4-1. Installation Place

• A place which provides the spaces around the outdoor
unit as required above in the diagram.

• A dr y sunny place. If the place is exposed to direct
sunlight use an awning for protection.

•

A place which can bear the weight of the outdoor unit and
does not allow an increase in noise level and vibration.

• A place where the operation noise and discharged air
do not disturb your neighbors.

• A place which is not exposed to a strong wind.

• A place free of a leakage of combustible gases.

• A place which does not block a passage.

• When the outdoor unit is to be installed in an elevated
position, be sure to secure its feet.

• A place where the drain water does not raise any problem.

• An allowable length of the refrigerant piping is up to 15 m.

• An allowable heat level is up to 6 m.

CAUTION

1. Install the outdoor unit without anything blocking

the air discharging.

2. When the outdoor unit is installed in a place

exposed always to a strong wind like a coast or
on a high story of a building, secure the normal
fan operation using a duct or a wind shield.

3. Specially in windy area, install the unit to

prevent the admission of wind.

– 19 –

4. Installation in the following places may result

trouble. Do not install the unit such places.

• A place full of machine oil.

• A saline-place such as coast.

• A place full of sulfide gas.

• A place where high-frequency

waves are likely to be
generated as from
audio equipment,
welders, and
medical
equipment.

8-4-2. Refrigerant Piping Connection

Flaring

2. Insert a flare nut into the pipe, and flare the pipe.

Outer dia.

(mm)

6,35 1,3 0,7 0,8
12,7 1, 8 1,0 to 1,1 1,0

Tightening Connection

Align the centers of the connecting pipes and tighten
the flare nut as far as possible with your fingers Then
tighten the nut with a spanner and torque wrench as
shown in the figure.

• Do not apply excess torque.
Otherwise, the nut may crack depending on the conditions.

1. Cut the pipe with a pipe cutter.

90˚

Fig. 8-4-2

A (mm)

Imperial Rigid

CAUTION

Strong
wind

Fig. 8-4-1

Obliquity Roughness Warp

Thickness

(mm)

Die Pipe

Fig. 8-4-3

Outer dia. Tightening Additional

(mm) torque tightening torque

6,35 16 (1,6 kgf•m) 18 (1,8 kgf•m)
12,7 49 (5,0 kgf•m) 54 (5,5 kgf•m)

Half union

Externally
threaded side

Use a wrench to secure.

Flare nut

Use a torque wrench to tighten.

Fig. 8-4-4

8-4-3. Evacuating

AIR PURGE

Evacuate the air in the connecting pipes and in the
indoor unit using vacuum pump. Do not use the
refrigerant in the outdoor unit.

For details, see the manual of vacuum pump.

Use of vacuum pump

1. Connect the charge hose (A) from the manifold valve
to the charge inlet of the gas side packed valve.

2. Connect the charge hose (B) to the port of vacuum
pump.

3. Open fully the low pressure side handle of the
manifold valve.

4. Operate the vacuum pump.

5. Close the low pressure side handle of manifold valve
after evacuating and stop the vacuum pump.

Continue evacuating more than 15 minutes and check
the pressure gage indicates –0,1 MPa (–76 cm Hg).

6. Open the stems of packed
valves A and B1 all the way.

7. Securely tighten the stem
cap to each of the packed
valve stems.

Indoor unit

C

A

Gas
(Ø12,7)

D

B

1

Liquid
(Ø6,35)

Low pressure
side handle

Outdoor unit

Service port

Packed
valve

Pressure
gage

Fig. 8-4-5

CAUTION

• KEEP IMPORTANT 4 POINTS FOR PIPING W ORK

(1)Take away dust and moisture

(Inside of the connecting pipes.)
(2)Tight connection (between pipes and unit)
(3)Evacuate the air in the connecting pipes using

VACUUM PUMP.
(4)Check gas leak (connected points)

A

Packed V alve Handling Precautions

• Open the valve stem all the way out; so not try to
open it beyond the stopper.

• Securely tighten the valve stem cap torque is as follows;
Gas pipes side (ø12,7 mm) : 49 N•m (5,0 kgf•m)
Liquid pipe side (ø6,35 mm) : 16 N•m (1,6 kgf•m)

Flare nut

Valve body

Valve stem

Hexagon wrench is required.

Stopper

5mm

Valve stem cap

(Unit : N•m)

Internally
threaded side

Manifold valve

Lo Hi

Charge
hose (B)

Charge
hose (A)

Fig. 8-4-6

High
pressure
side
handle

VP

8-4-4. Electrical Work

How to connect the power cord

For the air conditioner that has no power cord,
connect a power cord to it as mentioned below.

• Remove the electric parts cover from the outdoor
unit. (4 screws)

• After removing the electric parts cover, remove
the cord clamp.

• Connect and secure the power supply cord.

Earth line

Cord
clamp

Terminal block

N

L

Screw

2

1

Power
supply
cord

3

Terminal block

Earth line

Screw

Cord
clamp

Connecting
cable

Fig. 8-4-7

Stripping length of power cord

90mm

10mm

N
L

10mm

80mm

Fig. 8-4-8

Earth line

NOTE

• Use standard wire only.

• Wire type : 3,5 mm² or
more AWG-12.

WARNING

To plug the cable in the plug receptacle, take
the following precaution.

THIS APPLIANCE MUST BE EARTHED.

IMPORTANT

THE WIRES IN THIS MAINS LEAD ARE
COLORED IN ACCORDANCE WITH THE
FOLLOWING CODE :

L

: Brown

N

: Blue
: Green and Yellow

As the colors of the flexible cord of this
appliance may not correspond with the colored
markings, to identify terminals in your plug, as
follows :

Connect BROWN colored core to plug terminal
marked letter “L”.

Connect BLUE colored core to plug terminal
marked letter “N”.

Connect GREEN and YELLOW colored core to
plug terminal marked Earth symbol “

The installation of the cables has to be done in
such a way that the basic insulated wires for the
infrared sensor can not be touched.

Use the power supply cord/cables with
thickness, type, and protective devices
specified in the installation manual.

Prepare the interior power supply cord and
cables wiring with current capacity sufficient for
starting and usage of air conditioner.

-LIVE

-NEUTRAL

-EARTH

Fig. 8-4-9

L
N

”.

Model RAS-18YAH-E RAS-18YAH-A

Power source
Maximum running current 16,8 A
Plug socket & fuse rating 20 A
Wiring 3,5 mm² (AWG-12) or more

(RAS-18YKH-E) (RAS-18YKH-A)

50 Hz ~, 220 – 240V

50 Hz ~, 240V

CAUTION

If incorrect/incomplete wiring is carried out, it
will cause an electrical fire or smoke.

Prepare the power source for exclusive use with
the air conditioner.

This product can be connected to the mains.

Connection to fixed wiring :
A switch or circuit breaker which disconnects all

poles and has a contect separation of at least 3
mm must be incorporated in the fixed wiring.

An approved short circuit breaker or switches
must be used.

8-4-5. Wiring Connection

1. Remove the electric parts cover from the
outdoor unit. (4 screws)

2. Connect the connecting cable to the terminal as
identified with their respective matched numbers
on the terminal block of indoor and outdoor unit.
(1,3 mm² AWG-16 or more)

3. When connecting the connecting cable to the
outdoor unit terminal, make a loop as shown
installation diagram, to prevent water coming in
the outdoor unit.

4. Insulate the unused cords (conductors) with
strip the sheath of connecting cable to prevent
the shortage or electric leakage.

Process them so that they do not touch any
electrical or metal parts.

Stripping length of connecting cable

60mm

Earth line

10mm

3

2
1

10mm

50mm

Fig. 8-4-10

Connecting
cable

123

Screws

Cord clamp

Terminal
block

Terminal
screw

CAUTION

1. Wrong wiring connection may cause some
electrical parts burn out.

2. Be sure to use the cord clamps and the
electric parts cover to the specified positions
with attached to the product.

Mount the electrical parts cover for cables of
connecting section firmly with the screws.

3. Do not damage or scratch the conductive
core and inner insulator of power supply and
inter connecting cables when peeling them.

4. Be sure to comply with local cords on running
the wire from indoor unit to outdoor unit (size
of wire and wiring method etc.) Wire type :
More than H05 RN-F

5. Use the power supply cord and inter-connecting
cable with specified thickness, specified type,
and protective devices specified.

6. No wire should touch refrigerant piping,
compressor of any moving parts.

9. TROUBLESHOOTING CHART

Troubleshooting Procedures :

• Following details of “What to be pre-chec k ed
first”, make sure of the basic items.

• When there is no trouble corresponding to
above, chec k in detail the faulty parts follow­ing “How to judge f aulty parts by symptoms”
later.

9-1. What to be Prechecked First

9-1-1. Power Supply Voltage

The line voltage must be A C 220–240V (RAS­18YKH-E, RAS-18YAH-E), 240V (RAS-18YKH-A,
RAS-18YAH-A). If the line voltage is not within this
range, this air conditioner may not work normally.

No.

Operation of air-conditioner

9-1-2. Incorrect Cable Connection between

Indoor and Outdoor Units

The indoor unit is connected to the outdoor unit with
4 cables. Make certain that the indoor and outdoor
units have been connected properly, with terminals
assigned the same numbers wired to each other.
If the connectors are not connected as specified, the
outdoor unit will not operate normally, or OPERA­TION lamp and TIMER lamp will flash (5Hz).

9-1-3. Misleading but Good Operations

(Program Controlled Operation)

The microcomputer performs the operations listed in
Table 9-1-1 to control the air conditioner. If a claim
is made on the operation, check whether it corre­sponds to the contents in the Table 9-1-1.
If it does, it is an indispensable operation for the
control and maintenance of the air conditioner: it is
not a failure of the unit.

T able 9-1-1

Description

1

When the breaker is turned on, the
OPERATION lamp on the setting
indication part flashes.

2

Fan speed remains unchanged in the
dry mode.

3

Room temperature is in the range
under which the compressor is turned
off, but the compressor will not stop.

4

The compressor will not switch on or
off even when the thermo control is
operated in the dry operation.

5

The PRE-DEF. lamp comes on when
the heating operation is started.

6

The outdoor fan stops once in the
while during the heating operation.

7

Compressor does not work though
room temperature is in the range of
turning the compressor on.

8

During automatic operation, the
operation mode changes.

The OPERATION lamp flashes, indicating that power is
turned on. If this happens, push the START/STOP b utton
once to cause the lamp to stop flashing. A po wer outage
also causes the lamp to flash.

Fan speed is automatically controlled in the dry mode.

The compressor will not stop while the compressor on hold
timer (3-minutes timer) is actuated.

In the dry mode, the compressor goes on and off at regular
intervals, independent of the thermo control.

The PRE-DEF. lamp comes on during defrost operation and
when the indoor heat exchanger temperature is low when the
heating operation is started. At this time, the indoor fan is
stopped to prevent cold air from drifting into the room.

• When the indoor heat exchanger temperature is high, the
outdoor fan may be stopped b y the high-temper ature limit
control operation.

Compressor does not work while the compressor restart
delay (3-min.) timer is active. The same is true after power is
turned on, as the time is still active.

After selection of the cooling and heating operation, the
operation mode is selected again when the compressor off
mode continues for 15 min. according to the room tempera­ture.

9

During automatic operation mode, the
fan only operation continues.

When the room temperature is within setting temperature ±
1°C the fan only mode is selected.

– 20 –

9-2. Primary Judgment of Trouble

Sources

9-2-1. Role of Indoor Unit Control

The indoor unit controller receives the operation
commands from the remote control and assumes
the following functions.

• Measurement of the draft air temperature of the
indoor heat exchanger by using the thermo
sensor (TA).

• Louver motor control

• Control of the indoor fan motor operation

• Control of the LED display

• Sends the operation signal to the outdoor micro­computer.

9-2-2. Display of Abnormalities and

Judgement of the Abnormal Spots

The indoor unit of this machine observes the opera­tion condition of the air conditioner and displays the
contents of the self-diagnosis as block displa ys on
the display panel of the indoor unit.

T able 9-2-1

Block display

A

OPERATION display flashing (1 Hz)

B

OPERATION display flashing (5 Hz)

C

OPERATION display flashing (5 Hz)

D

OPERATION display flashing (5 Hz)

E

OPERATION display flashing (5 Hz)

F

OPERATION and TIMER display flashing (5 Hz)

G

OPERATION, TIMER and PRE-DEF. display
flashing (5 Hz)

H

OPERATION, TIMER and PRE-DEF. display
flashing (5 Hz)

(1) Judgement from defective operation or abnormal operation

T able 9-2-2

Po w er f ailure (when power is ON)
Thermo sensor (TA) short/break
Heat exchanger sensor (TC) short/break
Indoor fan lock, abnormality of indoor fan
Indoor P.C. board failure
Wrong wiring of connecting cable

• Gas shortage, other refrigerant cycle trouble

• Heat exchanger sensor open/break/short

• Overload relay or thermostat for compressor
trouble

Cycle abnormal

Block display

Symptom

No reaction on
remote control
operation

The outdoor fan
does not rotate

Check

Turn off the power once, turn it on
again and try to operate the remote
control again.

The compressor operates.

The compressor does not operate.

– 21 –

Remote control is
not possible.

Remote control is
possible.

Primary judgement

The indoor part (including the
remote control) is defective .

OK.

The outdoor part is defective.
(outdoor fan motor)

The inside part is defective.

(2) Self-diagnosis with remote control

With the indoor unit control, self-diagnosis of
protective circuit action can be done by turning
the remote control operation into service mode,
operating the remote control, observing the
remote control indicators and checking whether
TIMER lamp flashes (5 Hz).

Note :

• T o perf orm this self-diagnosis, the remote
control with the service code of 43069666
is required.

<How to select remote control operation mode>

1) Selecting service mode

Push the switch button pro vided on rear
bottom of the wireless remote control with a
tip of pencil for more than 3 seconds.

Make sure the setting temperature is
displayed on the display and other display is

turned off.

2) Selecting ordinary mode

Push the all clear button (ACL) on the rear
bottom of the wireless remote control with a
tip of pencil for more than 3 seconds. Make
sure the operation mode display, wind volume
display, clock display and setting temperature
display are turned on and “ : ” of the clock
display is flashing.

<Cautions when doing service>

1) After completion of servicing, always push
the all clear (ACL) button to return the
operation mode to the normal mode.

2) After completion of servicing by the check
code, turn off the power once and then turn
on the power to reset memorized contents of
the microcomputer to the initial status.

ACL CLOCK

(Rear bottom of remote control)

Fig. 9-2-1

All clear button

Switch for selecting
service mode

ACL

CLOCK

Rear bottom cover

– 22 –

<Self-diagnosis by check codes>

1) The self-diagnosis by the check codes is con­ducted under the block displays of item B-H in
Table 9-2-1.

2) Remote control key operation under the service
mode is conducted by ON/OFF or TEMP. The
remote control display by each key operation is
varied as shown below . Two digit number is
displayed in a he xadecimal n umber .

3) The self-diagnosis by the check codes is con­ducted with procedures shown below .

a) Enter the service mode and make sure the

off timer display of the remote control shows

.

b) Operate the “ON/OFF” key and mak e sure

the timer lamp on the display section is
flashing (5 Hz).

c) At the same time, also make sure the opera-

tion lamp is also flashing. This shows that
the protection circuit on the indoor P.C. board
is working.

d) Operate the TEMP. key and make sure

the remote control display shows and
flashing of the operation lamp. If the opera­tion lamp is flashing, it shows the protection
circuits for connecting cable is working or
thermal fuse is blown.

e) In the same way, operate the TEMP.

key so that the displa y is increased one by
one to continue checks by the self-diagnosis

as shown in the next table. From up to

check operations of protection circuits

for each block, and to check
operations of the typical protection circuits.

Operating key

ON/OFF

TEMP. (Up)

TEMP. (Down)

“AUTO” LOUVER

“SET” LOUVER

T able 9-2-3

Indication after operation

1 is added to data before operation.
(Example)

1 is subtracted from data before operation.
(Example)

10 is subtracted from data before operation.
(Example)

Data before operation is directly transferred.
(Example)

➞

➞

➞

➞

– 23 –

T able 9-2-4

Block level

Check

code

Block

Indoor P.C.
board

Cable
connection

Refrigerant
system

Check

code

Diagnosis function

Symptom

Indoor temp. (TA) sensor is
out of place.
Disconnection or short-circuit

Indoor temp. (TC) sensor is
out of place.
Disconnection or short-circuit

Trouble on indoor fan
Abnormal revolution speed of
fan

Indoor unit or other part is
defective.
EEPROM access error

Outdoor temp. sensor is out of
place.
Disconnection or short-circuit

Outdoor temp. sensor is out of
place.
Disconnection or short-circuit

Discharge temp. error
Detection of discharge temp.
over the set value

High-pressure switch
operation
IOL operation

Serial signal is not sent from
the outdoor unit to the indoor
unit.

• Miswiring of crossover wire

• Serial send circuit of the
outdoor P.C. board is
defective.

• Serial receive circuit of the
indoor P.C. board is
defective.

Trouble on the four-way valve
system

• After cooling operation has
started, the indoor heat
exchanger temp. rises.

• After heating operation has
started, the indoor heat
exchanger temp. lowers.

Trouble on other cycle line

• After cooling/heating
operation has started, the
indoor heat exchanger
temp. (TC) does not vary.

• When the compressor stop
command is sent by freeze­preventing control.

Compressor break down.

Air

Conditioner

status

Operation
continues.

Operation
continues.

All off

Operation
continues.

All off

All off

All off

All off

Operation
continues.

Operation
continues.

Operation
continues.

Operation
continues.
Compres­sor stops.
Indoor fan
LOW

All off

Condition

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Displayed when
error is detected.

Indicated when
detected
abnormal

Judgment and action

1. Check the indoor temp. sensor (TA).

2. Check the indoor P.C. board.

1. Check the indoor temp. sensor (TC).

2. Check the indoor P.C. board.

1. Check the connector circuit for
revolution speed input (CN13).

2. Check the indoor fan.

3. Check the indoor P.C. board.

1. Check the indoor P.C. board.
(EEPROM and peripheral circuits)

1. Check the outdoor temp. sensor (TE).

2. Check the P.C. board.

1. Check the outdoor temp. sensor (TD).

2. Check the P.C. board.

1. Check the refrigerating cycle
(Gas leak).

2. Check the pipe sensor (TD).

1. Check the high-pressure switch.

2. Check the circuits of high-pressure
switch line.

• Disconnection and contact failure of

CN04 connector

• Check the P.C. board.

3. Overload operation of the refrigerating
cycle

1. In case that the outdoor unit does not
operate at all,

• Check crossover wire./Correct

miswiring.

• Check the outdoor P.C. board.

2. In case that the outdoor unit operates
normally,

While the outdoor send Serial LED (Green)
on the indoor P.C. board flashes , If the
receive Serial LED (Orange)
Flashes : Check the indoor P.C. board.
Does not flash : Check the outdoor P.C. board.

1. Check the four-way valve.

2. Check the indoor heat exchanger
sensor (TC).

3. Check the indoor P.C. board.

1. Inner overload relay operation of
compressor case thermostat
(Electromagnetic contact OFF-STOP)

2. Indoor heat exchanger sensor sensing
part out of place

3. Check the indoor heat exchanger
sensor (TC).

4. Check the indoor P.C. board.

1. Check the charged amount of
refrigerant gas.

• Gas shortage →

Gas refilling, gas leak check

2. Check the indoor fan. (Lock)

1. Check compressor.

2. If it is OK, check P.C. board.

Contents detected by the check codes to are stored in memory of the microcomputer even if the power supply is turned off.
Therefore, contents of operations in the past are all displayed.

– 24 –

Details of Table 9-2-2

Judgment of Trouble by Every Symptom

[04 Serial signal error]

Does outdoor

unit operate?

YES

Does LED (Orange)

on indoor

P.C. board flash?

YES

NO

Are 1, 2, and 3 crossover

wires normal?

YES

Is connection of

connector normal?

YES

Does LED (Orange) on

outdoor P.C. board flash?

YES

NO

Does LED (Green) on

outdoor P.C. board flash?

YES

NO

NO

NO

NO

Check outdoor P.C. board.
Failure

Check indoor P.C. board.
Failure

Correct crossover wires.

Correct connection
of connector.

Replace
P.C. board.

Replace
P.C. board.

[08 Four-way valve error]

Is operation of

four-way valve normal?

YES

Is characteristic of

TC sensor resistance

value normal?

NO

NO

YES

• Refer to the Characteristic diagram.
10k

Has coil

terminal 220–240V

in heating?

Are circuit

wires normal?

Outdoor P.C. board

check?

at 25˚C

Unsatisfied

YES

YES

Satisfied

NO

NO

– 25 –

Four-way valve check
Failure

Outdoor P.C. board check
Failure

(CN11 220–240V)

Indoor P.C. board check
Failure

Replace

Circuit check/modification

Replace
P.C. board.

Replace
P.C. board.

Replace TC sensor.

[09 Other cycle error] (1)

NO

Replace
TC sensor.

YES

Correct
connection

Does compressor

operate?

YES

Does compressor

tune off halfway?

NO

Is characteristic of

TC sensor resistance

value normal?

YES

• Refer to the
Characteristic
diagram.

at 25˚C

10k

Isn't TC sensor

disconnected from

the sensing part?

NO

NO

YES YES

Doesn't
inner over-relay
(in compressor)

operate?

NO

Is circuit wiring

normal?

YES

Outdoor

P.C. board

check?

Normal

NO

Failure

Check charged amount of refrigerant.
Check abnormal overload.
Trouble on compressor

Replace
compressor

Wiring check/modification

Replacement failure
of outdoor P.C. board

Indoor P.C. board check
Failure

Replace
P.C. board.

Replace
P.C. board.

[09 Other cycle error] (2)

NO

Is connection of

connector normal?

Modify
connection
of connector

NO

Replace
condenser.

NO

Replace
fan motor.

Is condenser

normal?

Is indoor fan

motor normal?

YES

YES

YES

NO

Does indoor
fan operate?

Isn't filter clogged?

Is characteristic of

TC sensor resistance

value normal?

Is charged amount

of refrigerant normal?

YES

Is outside air

low load?

YES

YES

NO

NO

Refer to Characteristic diagram.

at 25˚C

YES

Amount (1,45kg) charged in factory.

NO

10k

NO

YES

Freeze-preventing
operation

Freeze-preventing
operation

Clean filter.

Replace
TC sensor.

Addition of
refrigerant

Indoor P.C. board check
Failure

– 26 –

Replace
P.C. board.

[0C Indoor TA sensor error]

Is connection of CN04

TA sensor connector normal?

YES

Is characteristic of TA sensor

resistance value normal?

YES

[0d Indoor TC sensor error]

Is connection of CN05

TC sensor connector normal?

YES

Is characteristic of TC sensor

resistance value normal?

YES

NO

NO

• Refer to Characteristic diagram.
10k

at 25˚C

Indoor P.C. board check
Failure

NO

NO

• Refer to Characteristic diagram.
10k

at 25˚C

Modify connection
of connector.

Replace
TA sensors.

Replace
P.C. board.

Modify connection
of connector.

Replace
TC sensors.

[18 Outdoor TE sensor error]

Is connection of TE sensor

connector normal?

YES

Is characteristic of TE sensor

resistance value normal?

YES

Indoor P.C. board check
Failure

NO

NO

• Refer to Characteristic diagram.
10k

at 25˚C

Outdoor P.C. board check
Failure

– 27 –

Replace
P.C. board.

Modify connection
of connector.

Replace
TE sensors.

Replace
P.C. board.

[19 Outdoor TD sensor error]

Is connection of TD sensor

connector normal?

YES

Is characteristic of TD sensor

resistance value normal?

YES

[1E Discharge temp. error]

NO

NO

• Refer to Characteristic diagram 4 and 5.
10k

at 25˚C

Outdoor P.C. board check
Failure

Modify connection
of connector.

Replace
TL/TD sensors.

Replace
P.C. board.

Is protective

control such as discharge

thermostat normal?

YES

Is charged amount

of refrigerant normal?

YES

Isn't it abnormal

overload?

NO

Is characteristic of

TD sensor resistance

value normal?

YES

NO

NO

YES

NO

• 10k

at 25˚C

Are wiring/connector

connection normal?

Outdoor P.C. board check
Failure

NO

Modify wiring/connector
connection.

Check and modify charged
amount of refrigerant.

1,45kg

Make better/delete the cause.

Replace TD sensor.

Replace P.C. board.

– 28 –

9-3. T r oubleshooting Flo wcharts

9-3-1. Power cannot be Turned on (No Operation at All)

< Preliminary checks >

(1) Is the supply voltage normal?
(2) Is the connection to the AC output OK?
(3) Are the connection of the primary side and the secondary

side of the power transformer inserted into the P.C. board?

(4) Is the FUSE (F01) blown?

Turn the power off for about 5
seconds and then turn it on again.

Does the OPERATION

lamp flash?

NO

YES

Does the transmission indicator of the

remote control flash normally, and is

Does operation start

when you push the ON/OFF button

of the remote control?

NO

the transmission really performed?

YES

Is the lead wire disconnected from

the infrared rays receive parts?

NO

Infrared rays receive parts

or P.C. board failure

YES

NO

YES

(Normal)

Remote

control

failure

Operations

Check items

Probable

main causes

Remedies

Item by

symptoms

Replace

Connect the

wire properly

Replace

Is 50Hz 220–240V AC
supplied to the primary side of
the power source transformer?

YES

Is 12V AC supplied

to the secondary side

of the power transformer?

YES

Is the voltage display on the rear

panel of the P.C. board normal?

(12V DC or 5V DC)

12V DC, 5V DC power supply circuit failure

(DB01, C01, Q03, D01, Q01, Q02, lC03)

Refer to the figure below.

Refer to the figure below.

NO

Transformer P.C. board (MCC-629) Main P.C. board (MCC-1293)

NO

NO

YES

CN32 CN33 CN01 CN12

Primary side

Secondary side

Refer to above “Preliminary checks”.
Or there is a defect before the power transformer.

Power

transformer

is failure

Microcomputer

is failure

Replace

transformer

Replace the

P.C. board

Replace the

P.C. board

Fig. 9-3-1 P o wer transf ormer connection diagram

– 29 –

9-3-2. Only the Indoor Fan does not Operate

< Preliminary checks >

Does it neither work in COOL or FAN ONLY operation?

< Checking procedure >

Turn OFF the power

(“REMOTE CONTROL” position)

Turn ON the power

(“REMOTE CONTROL” position)

Does the fan stop at the

operation stop condition?

YES

Start operation at HIGH cooling

Does the fan rotate?

YES

Change the setting

to LOW cooling

Does the rotating speed

of the fan lower?

YES

NO

NO NO

NO

Stop the

operation

Control P.C. board failure

Does 120V AC or higher

voltage apply to between red and

black lead of the motor?

YES

Turn OFF the power

Is it possible to rotate the

cross flow fan by hand?

YES

Turn ON the power

NO

Replace the

P.C. board

Motor control
circuit failure
(lC01, 05, D04) or
12V power circuit
(Q03, D01) or
thermal fuse failure.

Repair the

cross flow fan

Normal

When rotating the

cross flow fan by hand at

the operation stop condition,

is the rotation signal (+12VDC

detected between (2) (gray lead)

and (3) (brown lead) of the motor

connector (PJ13 or CN13)?

(1 pulse/1 revolution)

YES

Motor circuit (D03, Q06, IC01)

or 12V power circuit

(Q03, D01) failure

– 30 –

0V)

NO

Replace the

fan motor

Replace the

control P.C. board

9-3-3. Wiring Failure (Interconnecting and Serial Signal Wire)

(1) Outdoor unit does not operate

1) Is the voltage between  and  of the indoor terminal block varied?
Confirm that transmission from indoor to outdoor is correctly performed based upon the following dia-

gram.

NOTE:

• Measurement should be performed 2 minutes and 30 seconds after starting of the operation.

• Be sure to prepare a diode for judgment.

Terminal block at indoor side

Red

White

Normal time : Voltage swings between DC15 and 60V.
Abnormal time : Voltage does not vary.

3
2

Terminal block

1

S5277G

S5277G or equivalent (G or J type)
(Diode with rated voltage of 400V
or more is acceptable.)

Tester

Fig. 9-3-2

(2) Outdoor unit stops in a little while after operation started

<Check procedure> Select phenomena described below.

(1) The outdoor unit stops 10 to 20 minutes after operation started, and 10 minutes or more are required to

restart the unit.

Gas circulation amount is down.

Measure gas pressure.

Thermo. operation of compressor

Gas shortage
Gas leak
Pipe clogging

Fig. 9-3-3

(2) If the unit stops once, it does not operate until the power will be turned on again.

To item of Compressor does not operate.

Fig. 9-3-4

(3) The outdoor unit stops 10 minutes to 1 hour after operation started, and an alarm is displayed.

(Discharge temp. error check code 03, 1E Sensor temp. error check code 02, 1C)

Gas leak
Miswiring of connecting wires of indoor/outdoor units
Clogging of pipe and coming-off of TC sensor

Fig. 9-3-5

– 31 –

Refer to the chart
of outdoor unit.

9-3-4. How to Check the P.C. Board

(1) Operating precautions

1) When removing the front panel or the P.C.
board, be sure to disconnect the power plug
from the AC outlet.

2) When removing the P.C. board, hold the edge
of the P.C. board and do not apply force to the
parts.

3) When connecting or disconnecting the
connectors on the P.C. board, hold the whole
housing. Do not pull at the lead wire .

(2) lnspection procedures

1) When a P.C. board is judged to be failure,
check for disconnection, b urning, or discol­oration of the copper foil pattern or this P.C.
board.

2) The P.C. board consists of the following 4
parts:

a. Main P.C. board part:

Po wer relay, indoor fan motor drive circuit and
control circuit, C.P.U . and peripheral circuits,
buzzer drive circuit and buzzer.

b. Infrared rays receive parts:

Infrared rays receiving circuit

c. Display:

LED

d. Switch P .C. board:

Wireless-control, TEMPORARY switch

e. Buzzer P.C. board:

Buzzer

f. Transf ormer P.C. board:

Transformer

Check the defects of the P.C. board f ollowing the
list below . (Referring to Table 9-3-1)

(3) Checking procedure

No. Procedure

1 Disconnect the power plug from the

AC outlet and remove the P.C. board
assembly from the elec tronic parts
base.

Remove the flat cable from the
terminal plate.

2 Turn the power ON.

If the OPERATION lamp flash (0.5
sec. ON, 0.5 sec. OFF), steps 1–3 in
the right column are not necessary.

3 Push the START/STOP button once

to set in operation mode.
(Do not set to the fan only or on-

timer mode.)

T able 9-3-1

Check point (Symptom)

ls the fuse blown?

Check power supply voltage.

1. Between CN12 1 and 3
(220–240V AC)

2. Between CN01 1 and 3
(12V AC)

3. Between TP6 (+5V) and GND
(5V AC)

4. Between TP7 (+12V) and GND
(12V DC)

Check power supply voltage.

1. Between terminals 2 and 3

2. Between terminals 1 and 2

Trouble cause

1. Application of shock voltage

2. Shor t-circuit of the indoor fan
motor

1. Defective power cord, power
switch, fuse or line filter, or
wrong wiring

2. Defective power transformer

3. Defective power circuit or
short-circuited load

4. Same as 3

5. Ther mal fuse operation

1. Miswiring

2. PF terminal is failure.

4 Start operation by using the

antirestart timer.

1. All LEDs of the OPERATION lamp, the
TIMER lamp, PRE DEF. lamp,
ECONO. lamp and AUTO lamp light
up.

2. After 3 seconds, normal display does
not appear.

– 32 –

Display is failure or



defect in the 9P



housing assembly.



No. Procedure

Check point (Symptom)

Trouble cause

5 Push the START/STOP button once

to set in operation mode.

1. Setting the anti-restar t timer

2. Cooling operation

3. Fan speed : AUTO

4. Set the temperature sufficiently
lower than the room temperature.

5. Continuous operation

6 Connect the motor connector to

“MOTOR” and turn the power ON.
Start operation as follows:

1. Set the operation mode to “FAN
ONLY''.

2. Set the fan speed to “HIGH”.

3. Continuous operation

Table 9-3-2 Approximate value of the sensor (thermistor) resistance (TA, TC)

1. The compressor does not operate.

2. The OPERATION lamp flashes.

1. There is a voltage of 120V or more
between the red and black motor
connector leads.

2. The motor does not rotate.
(But the key operation of the remote
control is accepted.)

3. Motor rotates but vibrates hard.

1. The temperature of the indoor
heat exchange unit is ex­tremely low.

2. Defective control P.C. board.

1. Indoor fan motor is failure.

2. Contact of the motor
connector is defective.

3. Main P.C. board is failure.

(•=• kW)

Temperature

Sensor

0°C 10°C 20°C 25°C 30°C

Thermo. Sensor 35,8 20,7 12,6 10,0 7,92

9-3-5. How to Reduce the Operation Time of

the Anti-restart Timer

• Drill 2 holes on the rear of the wireless remote
control unit.

Attach the diode (1S1555 or equivalent) to the
rivet inside the unit.

• Push the START/STOP button to start operation
with the diode attached.

Wireless remote control

Timer short diode

– 33 –

Fig. 9-3-6

Indoor Printed Circuit Board (P.C.B.)

B

MMC-1293

5V-power source transistor (emitter pin)

Switch board

A

12V-power source transistor (emitter pin)

D

Reset input (Pin 7)

C

Watchdog timer output

(CPU Pin 28)

Power source (R.S.SER)

Transformer
primary side

Temp. fuse
Transformer

secondary side
Light-receiving unit
Buzzer board

Louver

MMC-1275

J

Serial input LED (Orange) from outdoor

K

Serial output LED (Green) to outdoor

E

TA sensor input

Fan revolution
pulse input

F

TC sensor input

– 34 –

9-3-6. Judgment by LED Display on Outdoor P.C. Board

When the check code is checked at the outdoor unit side, the following indications are available b y LED and Dip
switch (DSW01).

T a ble 9-3-3 LED displa y and c heck code

LED

3 Yello w

4 Y ellow

1E Pipe sensor (TD)

temp. up protection

21 High-pressure switch

line circuit

Protective operation frequency of
sensor circuit error

Table 1

Table 2

Dip switch

ON

12

ON

12

1 Red

Timer short

18 Heat exchanger

sensor (TE) circuit,

19 Heat exchanger

sensor (TL) and pipe
sensor (TD) circuit

2 Yello w

20 Power line

protective circuit

• When LED 1 to 4 is indicated with light in order, the phase detect protection circuit operates regardless of
setting of Dip switch.

ON

12

1

RB03

10X

R93 R92

D18

D20
D22

R91

LED

D23

D24
D25
D26

CN28

R90

CN18

D40

2

22

2

3

D10

D41
D42
D43

CN29

1

4

D08
D09

D07

R23

CN17
CN19

007

SW01

D44
D45
D46
D47

R22

Q60

CN16

008

Indication exchange
Dip switch (SW01)

8

+5V

R64

C

C64

R65

Schematic Diagram of

Outdoor Control Board

D04 Orange
Serial receive LED

D05 Green
Serial send LED

Fig. 9-3-7. Dip switch and LED position

< T able 1 > < Ta ble 2 >

Dip

switch

ON

12

LED LED

1234

Check contents

Dip

switch

Normal operation
Timer short operation
20 Power line protective circuit
1E Pipe sensor (TD) temp.

up protection

21 High-pressure switch

line circuit

All
off

ON

12

Check 18 and 19. <See Table 2>

LED status

: Goes on : Fast flashing : Slow flashing : Goes off

– 35 –

1234

As

follows.

Check contents

Normal operation
Protective operation : Once
Protective operation : Twice
Protective operation : Three times

Protective operation :

Four times (Emergency stop)

18 Heat exchanger (TE) circuit
19 Pipe sensor (TD) circuit

Check 1E and 21. <See Table 1>

All
off

9-4. How to Check the Remote Contr ol (Including the Indoor P.C. Board)

There is no beep from
the indoor unit.

Push the START/STOP button.

The operation lamp of
the air conditioner main
unit does not light.

Is there direct
sunlight on the
receptor of the

air conditioner?

YES

NO

Is there any

thyristor

fluorescent light

near by?

YES

NO

Does the transmission

YES

NO

Is operation

possible when setting

the temporary switch of the

air conditioner main unit to

"TEST RUN" or

"TEMPORARY AUTO"?

NO

possible when the

transmitter is moved
nearer to the infrared
signal receiver of the

indicator flash?

Is operation

air conditioner?

YES

Battery life

NO

Short-circuit the metal
terminal at the side of the
battery compartment
(all-clear terminal) with a pencil.
(wait about 10 seconds)

Push the START/
STOP button

Does the

transmission

indicator light?

YES

NO

Avoid direct
sunlight.

Keep the air

conditioner away

from thyristor

fluorescent light.

YES

Can any signal tone
be heard in a transistor
radio when transmitting

within 5cm distance

from the radio?

YES

P.C. board is failure.

Replace

P.C. board.

After battery replacement,

Note:

shortcircuit the metal terminal at
the side of the battery compartment
(all-clear terminal) with a pencil.

– 36 –

NO

Replace the
batteries

NO

Normal

Is there any

beep and

operation?

YES

Remote control

is failure.

Replace remote
control.

10-1. Indoor Unit (1)

10. EXPLODED VIEWS AND PARTS LIST

430

429

414

431

416

415

432

417

402

407

403

411

404

401

410

405

408

413

406

Location Part

No. No.

401 43061192 Base, E-Parts
402 43T69022 P.C. Board Assemb ly,

Transformer MCC-602
403 43T61003 Base, Display
404 43T60001 T erminal Block, 2P
405 43T60002 T erminal Block, 3P
406 43T08105 Plate, Switch
407 43T63020 Holder, P.C. Board
408 43T69021 Display Assembly, LED
410 43T69019 Receiver, Infrared Ra ys ,

DK12
411 43T60032 Lead Assembly , Displa y, 9P
412 73T63021 P.C. Board, Assembly,

Switch, MCC-577

Description

412

Location Part

No. No.

413 43T60060 Cable Assembly , 3P
414 43T37002 P.C. Board, Assembly,

Buzzer, MCC460
415 43T69004 Sensor, Heat Exchanger
416 43T69005 Sensor, Thermostat
417 43T69056 P.C. Board, Assembly,

MCC-1293
429 43T60041 Fuse Set, Thermal
430 43T60059 Housing Assembly,

Secondary
431 43T60058 Housing Assembly , Primary
432 43T62028 Sheet Switch

Description

– 37 –

Indoor Unit (2)

201

207

235

231

213

208

203

222

223

236

232

206

221

210

224

209

234

215

216

220

229

205

230

212

226

202

225

233

214
204

217

218

219

228

227

211

Location Part

No. No.

201 43T03009 Panel Assembly, Front
202 43T03003 Body, Bac k, Assembly
203 43007181 Latch, Plastic
204 43T19015 Bushing, Body (Right)
205 43T19016 Bushing, Body (Left)
206 43T07019 Arm
207 43T07013 Cap, Screw
208 43009535 Grille assembly
209 43T09030 Grille
210 43T09031 Grille, Sub
211 43T11002 Pipe, Shield
212 43T11001 Pipe, Seald
213 43T07010 Bushing
214 43T49033 Holder, Pipe
215 43T20013 Fan, Cross Flow , CJ952
216 43T07012 Arm, Grille, Assembly
217 43T21026 Motor, Fan, A C200V240V,

50Hz, AFP-220-31-4B

218 43T39001 Band, Motor (Right)

Description

Location Part

No. No.

219 43T39013 Band, Motor (Left)
220 43T39014 Base, Bearing
221 43T44019 Evaporator
222 43T47006 Pipe, Delivery
223 43T47016 Pipe, Suction
224 43T22008 Bearing
225 43T19003 Holder, Sensor
226 43T62025 Cover, Electorical P arts
227 43T63002 Holder, Remote Control
228 43T69058 Remote Control
229 43T70005 Hose, Drain, 3M
230 43070168 Hose, Drain
231 43T80008 Air, Filter
232 43T19017 Frame, Main
233 43T82006 Plate, Assembly , Installation
234 43T85060 Owner's Manual
235 43080401 Frame , A, Filter
236 43080402 Frame , B, Filter

Description

– 38 –

10-2. Outdoor Unit

31, 32 28

40

38

7

36

37

27

26

401

31,32 35 33 34

1

6

39

11,
13

5

17, 25

18

8

19

3

9

44

29,
30

42

41

10

43

12,
14

4

23

46

24

9

2

20
22
21

Location Part

No. No.

Description

01 43T00024 Panel, Air Outlet
02 43T00025 Panel, Front
03 43T00026 Panel, Side
04 43T42002 Base Assembly
05 43T19012 Guard, Fin
06 43T19011 Guard, Fan
07 43T91001 Plate, Roof
08 43T42005 Plate, Valve, Packed
09 43T15001 Handle
10 43T43023 Condenser Assembly
11 43T46027 Valve, Packed 12,7
12 43T46016 Valve, Packed 6,35
13 43T47020 Bonnet
14 43T47018 Bonnet
15 43T47007 Tube, Capillary, 1,2DIA
16 43T47014 Tube, Capillary, 1,7DIA
17 43146482 Valve, 4 Way
18 43T46005 Valve, Checked
19 43141301 Compressor, PH280X3-4MS
20 43T49011 Base, Spring, A
21 43T49012 Base, Spring, B
22 43T49019 Spring, Buffer
23 43T21013 Motor, Fan, AC220–240V,

50Hz

Location Part

No. No.

Description

24 43T20010 Fan, Propeller, 490
25 43T46018 Coil, V-4 Way AC220–240V,

LB6
26 43T69059 Sensor
27 43T69060 Sensor, TD
28 43T52004 Switch, Magnet, FC-2S
29 43157238 Heater, Crank case
30 43193065 Spring
31 43T60071 Fuse
32 43T60029 Fuse Set, 30A, 250V
33 43T55021 Capacitor, 45MFD, 420V
34 43T55014 Capacitor, 3,5MFD, 450V
35 43T58008 Transformer, FT-67
36 43T60035 Terminal Block, 4P
37 43T60036 Terminal Block, 3P, 30A
38 43T60037 Filter, Clamp
39 43T62014 Protector, Cord
40 43T62015 Protector, Cord
41 43T96003 Clip, Cable
42 43T96001 Bushing
43 43T96004 Bushing, Cord
44 43T62013 Cover, E-Parts
46 43T79004 Nipple, Drain
401 43T69057 P.C. Board Assembly,

MCC-1275

– 39 –

TOSHIBA CARRIER CORPORATION

336 TADEWARA FUJI-SHI, SHIZUOKA-KEN, 416-8521, JAPAN