Carrier 42NQ018N, 38NY018N Service Manual

SERVICE MANUAL

AIR CONDITIONER

SPLIT WALL TYPE

FILE NO. SVM-10035-1

42NQ018N / 38NY018N

Revised Apr, 2010

CONTENTS

1. SPECIFICATIONS

2. CONSTRUCTION VIEWS

2-1 Indoor Unit
2-2 Outdoor Unit

3. WIRING DIAGRAM

4. SPECIFICATION OF ELECTRICAL PARTS

4-1 Indoor Unit
4-2

Outdoor Unit

5. REFRIGERATION CYCLE DIAGRAM

6. CONTROL BLOCK DIAGRAM

7. OPERATION DESCRIPTION

FILE NO. SVM-10035

7-1 Remote control
7-2 Outline of Air Conditioner Control

7-3 Description of Operation Circuit
7-4 Description of Safety and Reliability Prevention Function
7-5 ECO Operation
7-6 FILTER check lamp
7-7 Auto Restart Function

8. INSTALLATION PROCEDURE

8-1 Safety Cautions
8-2 Installation Diagram of Indoor and Outdoor Units
8-3 Installation
8-4 Indoor Unit
8-5 Outdoor Unit
8-6 Others

– 1 –

9. TROUBLESHOOTING CHART

9-1 Troubleshooting Procedure
9-2 Basic Check Items
9-3 Primary Judgement
9-4 Self-Diagnosis by Remote Control (Check Code)

9-5 Troubleshooting Flowcharts

Troubleshooting for Wiring

9-6
9-7 Troubleshooting for P.C. Board
9-8 Troubleshooting for Remote Control

HOW TO REPLACE THE MAIN PARTS

10.

10-1 Indoor Unit

Outdoor Unit

10-2

11. EXPLODED VIEWS AND PARTS LIST

11-1 Indoor Unit (E - Parts Assy)
11-2 Indoor Unit
11-3 Outdoor Unit

FILE NO. SVM-10035

–2 –

1. SPECIFICATIONS

FILE NO. SVM-10035

MODEL

42NQ018N / 38NY018N

ITEM Cooling Heating

Capacity

kW

Phase

Power source

Hz
Power consumption kW
Power factor %
Running Indoor A
Current Outdoor A
Starting current A
Moisture removal lit/h
Noise Indoor (H/M+/M/L+/L) dB

Outdoor dB

Refrigerant Name of refrigerant

Rated amount kg
Refrigerant control
Interconnection Gas side size mm
pipe Connection type

Liquid side size mm

Connection type

Maximum length m

(One way)

Maximum height m

difference

INDOOR UNIT

Dimensions Height mm

Width mm

Depth mm
Net weight kg
Evaporator type
Indoor fan type
Airflow volume High fan

Medium fan

Low fan

3

m

3

m

3

m
Fan motor output W
Air filter

OUTDOOR UNIT

Dimensions Height mm

Width mm

Depth mm
Net weight kg
Condenser type
Outdoor fan type
Airflow volume

3

m
Fan motor output W
Compressor Model

Output W
Safety device
Louver type
Usable outdoor temperature range °C

220V

5.10

V

1.58
98

7.05

56

/h
/h
/h

/h

2400

1000

840
750

15 ~ 43 -10 ~ 24

240V 220V 240V

5.45 5.565.12

1∅

220 - 240

50

1.60
96

1.51 1.55
98 97

0.30

6.65 6.70 6.35
31

2.0

44/42/39/37/35

57 57 58

R410A

1.53

Capillary tube

∅12.7

Flare connection

∅6.35

Flare connection

1

15*

2

20*

8

42NQ018N

320

1050

228

13

Finned tube

Cross flow fan

1000

900
770

30

Honeycomb woven filter with PP frame

38NY018N

715
780
290

47

Finned tube

Propeller fan

2550 2400 2550

42

PA200X2CS-4KU1

1500

Td Sensor, Fuse, IOL

Automatic louver

Note *1 Chargeless pipe

*2 Maximum pipe

− 3 −

Note : 1

• Capacity is based on the following temperature conditions.

FILE NO. SVM-10035

Condition

Temperature

(DB) 27°C

Indoor unit inlet air temperature

(WB) 19°C

(DB) 35°C

Outdoor unit inlet air temperature

(WB) 24°C

Note : 2

• Charge refrigerant according to the table below.

Refrige rant

*1 No need to charge

extra refrigerant

*2 Need to charge

extra refrigerant

JIS C9612

Cooling

42NQ018N / 38NY018N

15 m or less

Over 15 m up to 20 m (20 g/m)

– 4 –

2-1 Indoor Unit

FILE NO. SVM-10035

2. CONSTRUCTION VIEWS

Grille Inlet

Front Panel

73.57

50

Knock out system

Heat exchanger

320

50

Air inlet

72

278 200 222 150

132

1050

Air outlet

200

Air filter

228

73.5

50

7

Knock out system

50

7278

78

157

Drain hose (0.5m)

320

40

525

Hanger

Connecting pipe (0.39m)
(Flare

12.70)

85 23

Hanger

6

5

Hanger Hanger

262.5

786

235

215

Center line

Installation plate outline

Connecting pipe (0.49m)
(Flare 6.35)

235

215

262.5

Hanger

For stud bold (
For stud bold (

6

5

10947 215.5 153.5

56

Wireless remote controller

63

Remote controller holder

6)
8~

10)

Outline of indoor unit

40

19

125

26

– 5 –

2.2 Outdoor Unit

600

50
36

R

15

FILE NO. SVM-10035

A

28

125108

6 hole

320

306

Ø

R

5.5

A Detail Drawing (Back leg)

HANDLE

290

320

Ø

Ø

715

86

25 Drain outlet

FAN-GUARD

436

275

90 600 90 69

2Ø11x14 Hole
(For

Ø8-Ø

10 anchor bolt)

B

306

320

Hole

6

Ø

11x14 Hole

Ø

36
50

B Detail Drawing (Front leg)

320
342

R

15

HANDLE

COVER-PV

Z

100 or more

320

100 or more

Z View

600

Air inlet

Air out

let

00 or more

6

Installation dimension

600 or more

4x

54

129

84

11 Long holes(For

Ø

Service port

10 anchor bolt)

Ø8-Ø

Electrical part cover

Liquid side
(Flare Ø6.35)

Gas-side
(Flare Ø 12.70)

– 6 –

3. WIRING DIAGRAM

FILE NO. SVM-10035

OUTDOOR
TERMINAL
BLOCK

POWER SUPPLY
220- 240 V ~ 50 Hz

L

BLK

RED

BLK

1/L1 5/L3

2/T1 6/T3

RED

WHI
PNK

COMPRESSOR

2

1

3

GRN&YEL

2

N

FERRITE CORE

RED

MAGNETIC

CONTACTOR

1

3

i

CHASSIS

A1

52C

A2

CAPACITOR CAPACITOR

S

C

BLK

R

RED

WHI
RED

FAN MOTOR

TRANSFORMER

OUTDOOR
UNIT

BLK BLK

BLK

BLK

RED

RED

BLK

BLK

WHI

RED

GRY

BLU

YEL

BLU

BLU
COIL FOR
4 WAY VALVE

MAIN P.C. BOARD (MCC-890)

1

1
2

CN06

3

3

1

1

CN05

3

3

SG01

1

1

F01

3

3

250VAC T6. 3A

5

5

CN01

7

7

9

9

1

CN11

313

11

33

CR11

CN02

CR12

CR13

TNR
R74

CN03

1
1

RY07

RY05

3

TNR
R73

RY06

CN07

CN08

DISCHARGE
PIPE
SENSOR (TD)

BLU

1

1
2
3

3

BLU

BLK

1

1
2
3

3

BLK

HEAT
EXCHANGER
SENSOR (TE)

– 7 –

FILE NO. SVM-10035

4. SPECIFICATION OF ELECTRICAL PARTS

4-1. Indoor Unit

No. Parts name Type Specifications

1 Fan motor (for indoor) ICF-340-30-2B DC 340V, 30W
2 Thermo sensor (TA-sensor) 10k at 25 C
3 Switching Transformer (T01)
4 Microcontroller unit (IC15) TMP87CM40ANG-6P68
5 Heat exchanger sensor

(TC-sensor)
6 Line filter (L01) LC*SS11V-R06270
7 Bridge rectifier (DB01)
8 Capacitor (C03)
9 Fuse (F01)

10 Varistor (R09, R10)
11 Resistor (R01 )
12 Louver motor

MP24Z3T

EKMH451VSN121MQ35S

SWT-77

D3SBA60

BET6.3A

SR561K14DO

RF-5TK1R8

DC 7V, 12V

12VDC

W

10k at 25 C

27mH, 600mA
4A, 600 V
120mF, 450 V

T6.3A, 250VAC

560 V

W

1.8 , 5 W

°

W

°

4-2. Outdoor Unit

No. Parts name Type Specifications

Output (Rated) 1500W, 2poles, 1 phase, 220 − 240V, 50Hz

1 Compressor PA200X2CS-4KU1 Winding resistance (Ω) Red-Black White-Black

(at 20°C) 1.85 2.62
Output (Rated) 42W, 4poles, 1 phase, 220 – 240V, 50Hz

2 Fan motor (for outdoor) FG-240-42A-1 Winding resistance (Ω) Red-Black White-Black

(at 20°C) 128 126

Running capacitor

3

(for fan motor)
Running capacitor

4

(for compressor)
Solenoid coil

5

(for 4-way valve)

6 Thermo sensor TE / TD 10kΩ at 25°C / 50kΩ at 25°C
7 Magnetic contactor A23T 220 − 240V, 50Hz
8 Transformer TT-05 220 − 240V

9 Microcomputer TMP47C840N
10 Varistor (R73, R74) 15G471K 470V
11 Fuse (F01) TSCR T6.3A, 250V

DS451305NPQB AC 450V, 3.0 µF

B32332I5606J063 AC 450V, 50µF

VHV (STF) AC 220 − 240V

− 8 −

FILE NO. SVM-10035

5. REFRIGERATION CYCLE DIAGRAM

Indoor unit

Cooling

0.39 m
(Connecting pipe)

Æ12.7

O.D.:12.7 mm O.D.:6.35 mm

Cooling

Heating

Heating

P

Packed valve

(Æ12.7)

Heating

4-way valve

Cooling

Discharge Muffler

∅

25x160L

Compressor

Accumulator

PA200X2CS-4KU1

Heat exchanger

Cross flow fan

T1

Capillary tube
Æ1.7 x 600

Packed valve

(Æ6.35)

Capillary tube

Æ2.0 x 1000

l

0.49 m

(Connecting pipe)

Æ6.35

l

Heat exchanger

Refrigerant
R410A : 1.53 kg.

Cooling
Heating

Propeller fan
Outdoor unit

Mark ( ) means check points of Gas Leak.

Ambient temp.

50Hz

Standard

pressure

(MPaG)

P

Surface temp. of heat

exchanger interchanging

pipe

T1

(°C)

Fan speed

(indoor)

conditions DB/WB

(°C)

Indoor Outdoor

Standard 2.53 42.0 High 20/15 7/6

Heating Overload*1 3.30 ~ 3.65 51.0 ~ 55.0 Low 27/- 24/18

Low temperature 1.75 32.0 High 20/

-

-10/-10

Standard 0.94 11.0 High 27/19 35/24

Cooling Overload 1.12 15.0 High 32/23 43/26

Low temperature 0.72 4.2 Low 21/15 21/15

Note

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

·

·

*1 During heating overload operation, a value for the high temperature limit control operation is included.

– 9 –

Heat Exchanger Sensor

6. CONTROL BLOCK DIAGRAM

Indoor Unit Control Panel

M.C.U.

Functions

• Louver Control

FILE NO. SVM-10035

Operation

Display

Temperature Sensor

Infrared Rays Signal Receiver

Initiallizing Circuit

Infrared

Rays

Remote

Control

From Outdoor Unit
AC 220-240V~ 50Hz

Clock Frequency

Oscillator Circuit

Power Supply

Circuit

Noise Filter

• 3-minute Delay at Restart for Compressor

• Motor Revolution Control

• Processing

(Temperature Processing)

• Timer

• Serial Signal Communication

Louver ON/OFF Signal

Louver Driver

Serial Signal Transmitter/Receiver

Serial Signal Communication

Timer

Display

Filter Sign

Display

PRE DEF.

Sign Display

Hi Power

Sign Display

Indoor

Fan Motor

Louver Motor

REMOTE CONTROLLER

Remote Controller

Infrared Rays, 36.7kHz

Operation [ ]

Operation Mode Selection

AUTO, COOL, DRY, HEAT,FAN ONLY

Thermo. Setting

Fan Speed Selection

ON TIMER Setting

OFF TIMER Setting

Louver AUTO Swing

Louver Direction Setting

ECO

Hi-POWER

− 10 −

7. OPERATION DESCRIPTION

7-1. Remote control

7-1-1. Remote control and its functions

Infrared signal emitter

1
2

Start/Stop button ( )
Mode select button ( )

3

Temperature button ( )

4

Fan speed button ( )

5

Swing louver button ( )

6

Set louver button ( )

7

On timer button ( )

8

ON

13

FILE NO. SVM-10035

1

5
4

3

Off timer button ( )

9

10

Sleep timer button ( )

11

Setup button ( )

12

Clear button ( )

13

Memory and Preset button ( )

14

High power button ( )

15

Economy button ( )

16

Filter reset button ( )

17

Clock reset button ( )

18

Check button ( )

OFF

7-1-2. Operation of remote control

1. AUTOMATIC OPERATION

To automatically select cooling, heating, or fan only operation.

1. Press MODE : Select A.

2. Press MODE : Set the desired temperature.

2. COOLING / HEATING / FAN ONLY OPERATION

10

18
16

2

14

6
7

8

15
12

9

11

17

1. Press MODE : Select Cool , Heat , or Fan only .

2. Press MODE : Set the desired temperature.
Cooling: Min. 17°C, Heating : Max, 30°C, Fan Only: No temperature indication

3. Press : Select AUTO, LOW , LOW+ , MED , MED+ , or

HIGH .

3. DRY OPERATION (COOLING ONLY)

For dehumidification, a moderate cooling performance is controlled automatically.

1. Press MODE : Select Dry .

2. Press MODE : Set the desired temperature.

4. Hi-POWER OPERATION

To automatically control room temperature and airflow for faster cooling or heating
operation (except in DRY and FAN ONLY mode)

Press HI-POWER : Start and stop the operation.

− 11 −

FILE NO. SVM-10035

5. ECO OPERATION

To automatically control room to save energy (except in DRY and FAN ONLY mode)

Press : Start and stop the operation.

Note: Cooling operation; the set temperature will increase automatically 1 degree/

hour for 2 hours (maximum 2 degrees increase). For heating operation the
set temperature will decrease.

6. TEMPORARY OPERATION

In case of the misplaced or discharged remote control

• Pressing the RESET button, the unit can start or stop
without using the remote control.

• Operation mode is set on AUTOMATIC
operation, preset temperature is 24°C
and fan operation is automatic speed.

7. TIMER OPERATION

Setting the ON Timer Setting the OFF Timer

RESET button

1

Press : Set the desired ON timer.

Press : Set the timer. Press : Set the timer.

2

3

3

Press : Cancel the timer. Press

ON

Press : Set the desired OFF timer.

OF F

: Cancel the timer

Daily timer allows the user to set both the ON & OFF timers and will be activated on a daily basis.

Setting Daily Timer

ON

1

Press

: Set the ON timer.

3

Press .

2

Press

OF F

: Set the OFF timer.

· During the daily timer is activation, both arrows are indicated.

( or )

Press button during the ( or )

4

mark flashing.

Note:

· Keep the remote control in accessible transmission to the indoor unit;
otherwise, the time lag of up to 15 minutes will occur.

· The setting will be saved for the next same operation.

8. PRESET OPERATION

Set your preferred operation for future use. The setting will be memorized by the
unit for future operation (except air flow direction).

1. Select your preferred operation.

2. Press and hold for 3 seconds to memorize the setting. The mark

displays.

3. Press : Operate the preset operation.

 − 12 − 

FILE NO. SVM-10035

9. AUTO RESTART OPERATION

To automatically restart the conditioner after the power failure (Power of the unit must be on.)

Setting

1. Press and hold the RESET button on the indoor unit for 3 seconds to set the
operation. (3 beep sound and OPERATION lamp blink 5 time/sec for 5 secpmds)

• Do not operate ON timer and OFF timer.

2. Press and hold the RESET button on the indoor unit for 3 seconds to cancel the
operation. (3 beep sound but OPERATION lamp does not blink)

10. SLEEP TIMER OPERATION

To start the sleep timer (OFF timer) operation

Press : Select 1, 3, 5 or 9 hrs for OFF timer operation.

 − 13 − 

7-1-3. Name and Functions of Indications on Remote Controller

[Display]

FILE NO. SVM-10035

All indications, except for the clock time indicator, are displayed by pressing the

1

Transmission mark

This transmission mark indicates when the
remote controller transmits signals to the indoor
unit.

2

Mode indicator

Indicates the current operation mode.
(A :

Auto, : Cool, : Heat, : Dry, : Fan only)

3

Temperature indicator

Indicates the temperature setting.

ºC ºC

(17 to 30 )

FAN speed indicator

4

Indicates the selected fan speed.
AUTO or five fan speed levels

(

LOW , LOW+ , MED , MED+ ,
HIGH ) can be shown.
Indicates AUTO when the operating mode is

either AUTO or : Dry.

TIMER and clock time indicator

5

The time setting for timer operation or the clock
time is indicated.

The current time is always indicated except
during TIMER operation.

6

Hi-POWER indicator

Indicates when the Hi-POWER operation starts.
Press the Hi-POWER button to start and press it

again to stop the operation.

7

(PRESET) indicator

Flashes for 3 seconds when the PRESET button is
pressed during operation.

The
button for more than 3 seconds while the mark is

blinks.

Press another button to turn off the mark.

ECO indicator

8

Indicates when the ECO is in activated.
Press the ECO button to start and press it again

to stop operation.

A, B change indicator remote controller

9

When the remote controller switching function is
set, "B" appears in the remote controller display.
(When the remote controller setting is "A", there is
no indication at this position.)

10

Swing

Indicates when louver is swing.
Press swing button to start the swing operation
and press it again to stop the swing operation.

mark is shown when holding down the

button.

1

6

9

3

8

7

2

10

5

4

– 14 –

FILE NO. SVM-10035

7-2. Outline of Air Conditioner Control

This is a fixed capacity type air conditioner, which uses
a DC motor for an indoor fan. The DC motor drive
circuit is mounted in the indoor unit. And electrical
parts which operate the compressor and the outdoor
fan motor, are mounted in the outdoor unit.
The air conditioner is mainly controlled by the indoor
unit controller. The controller operates the indoor fan
motor based upon commands transmitted by the
remote control and transfers the operation commands
to the outdoor unit.
The outdoor unit receives operation
commands from the indoor unit, and operates the
outdoor fan motor and the compressor.

(1) Role of indoor unit controller

The indoor unit controller receives the operation
commands from the remote control and executes
them.

• Temperature measurement at the air inlet of the

indoor heat exchanger by the indoor

temperature sensor

• Temperature measurement of the indoor heat

exchanger by the heat exchanger sensor

• Louver motor control

• Indoor fan motor operation control

• LED display control

• Transferring of operation commands to the

outdoor unit

• Receiving of information of the operation status

and judging of the information or indication of
error

(2) Role of outdoor unit controller

The outdoor unit controller receives the operation
commands from the indoor controller and
executes them.

• Compressor operation

control

• Operation control of

outdoor fan motor

Operations according
to the commands

from the indoor unit

• Turning off the compressor and outdoor fan

when the outdoor unit receives the shutdown
command

7-2-1. Louver control

(1) Vertical air flow louver

Position of veritcal air flow louver is automatically
controlled according to the operation mode.
Besides, position of vertical air flow louver can be
arbitrarily set by pressing [FIX] button.
The louver position which is set by [FIX] button is
stored in the microcomputer, and the louver is
automatically set at the stored position for the next
operation.

(2) Swing

If [SWING] button is pressed when the indoor unit
is in operation, the vertical air flow louver starts
swinging. When [SWING] button is pressed, it stops
swinging.

7-2-2. Indoor Fan Control

The operation controls the fan speed at indoor unit
side. The indoor fan (cross flow fan) is operated by

the phase control induction motor. The fan rotates in 3
stages in MANUAL mode, and in 3 stages in AUTO
mode, respectively. (Table 7-2-2)

1) When setting the fan speed to L, M or H
on the remote controller, the operation is performed
with the constant speed shown in Fig. 7-2-1

Table (7-2-1)

Indication

L
L+

M
M+

H

Fan speed

Low

(L + M) / 2

Med

(M + H) / 2

High

2) When setting the fan speed to AUTO on the remote
controller, revolution of the fan motor is controlled
to the fan speed level shown in Table 7-2-2 according
to the setup temperature, room temperature, and heat
exchanger temperature.

Table 7-2-1 Indoor fan and air flow rate

Cooling

OPERATION

MODE

42NQ018N

Model

Fan only

Dry M L L- UL SL

Heat

rpm

3

Air flow volume (m

/h)

3) When setting the fan speed to QUIET on the remote
controller, revolution of the fan motor is controlled
to the fan speed level is L-.

FAN TAP

UH H M L L- UL SL

HM LL-

UH H M L L- UL SL

1100

1000

1100 1000 940 870 850 850 750 640 550 550 550

1000 900 840 770 750 750 650 540 450 450 450

– 15 –

FILE NO. SVM-10035

7-3. Description of Operation Mode

(1) When turning on the breaker, the operation lamp

blinks. This means that the power is on (or the
power supply is cut off.)

(2) When pressing [START/STOP] button on the

remote control, receiving beep sounds from the
indoor unit, and the next operation is performed
together with opening the vertical air flow louver.

(3) Once the operation mode is set, it is memorized in

the microcomputer so that the previous operation
can be effected thereafter simply by pressing
[START/STOP] button.

7-3-1. Fan only operation

([MODE] button on the remote control is set
to the fan only operation.)

(1) When [FAN] button is set to AUTO, the indoor fan

motor operates as shown in Fig. 7-3-1. When
[FAN] button is set to LOW, MED, or HIGH, the
motor operates with a constant air flow.

°C

7-3-2. Cooling operation

([MODE] button on the remote control is set
to the cooling operation.)

(1) The compressor, 4-way valve, outdoor fan and

operation display lamp are controlled as shown in
Fig. 7-3-2.

° C



ON ON

OFF OFF OFF ON

4-way valve

Compressor

Outdoor fan

(Room temp.) (Preset temp.)

Preset
temp.

0.5

0

Fig. 7-3-2

display lamp

OPERATION

+3
+2.5
+2

+1.5
+1
+0.5

(Room temp.) − (Preset temp.)

Preset
temp.

0

(Preset temp.: 24 °C)

NOTE 1 : *1 : Fan speed = (M + − L) x 3/4 + L

*2 : Fan speed = (M + − L) x 2/4 + L
*3 : Fan speed = (M + − L) x 1/4 + L

2 : The ECO operation can not be set

(Linear approximation from M+ and L)

Fig. 7-3-1 Setting of air flow [FAN:AUTO]

M+

*1
*2
*3

(2) When [FAN] button is set to AUTO, the indoor fan

motor operates as shown in Fig. 7-3-3. When
[FAN] button is set to LOW, MED or HIGH, the
motor operates with a constant air flow.

°C

(Room temp.) − (Preset temp.)

Preset
temp.

+3
+2.5
+2
+1.5
+1
+0.5

0

-0.5

M+

*1
*2
*3

NOTE1 : *1 : Fan speed = (M + − L) x 3/4 + L

*2 : Fan speed = (M + − L) x 2/4 + L
*3 : Fan speed = (M + − L) x 1/4 + L

(Linear approximation from M+ and L)

-

16

Fig. 7-3-3 Setting of air flow [FAN:AUTO]

-

FILE NO. SVM-10035

7-3-3. Dry operation

([MODE] button on the remote control is set
to the dry operation.)

(1) The compressor, 4-way valve, outdoor fan and

operation display lamp are controlled as shown in
Fig. 7-3-4.

° C

ON:6min.

OFF:4min.

ON

ON:5min.

OFF:5min.

OFF

4-way valve

Outdoor fan

(Room temp.) (Preset temp.)

Preset
temp.

+3

+2

+1

ON:6min.

OFF:4min.

OFF

ON:5min.

OFF:5min.

OFF

0

Compressor

Fig. 7-3-4

7-3-4. Heating operation

(1) The compressor, 4-way valve, outdoor fan and

Preset
temp.

display lamp

OPERATION

([MODE] button on the remote control is set
to the heating operation.)

operation display lamp are controlled as shown in
Fig. 7-3-6.

° C

0

0.5

(Room temp.) (Preset temp.)

ON

OFF

ON

Compressor

ON

OFF

ON

4-way valve

Outdoor fan

OPERATION

display lamp

Fig. 7-3-6

(2) The microprocessor turns the compressor on and

off at the regular intervals (4 to 6 minutes). While
the compressor is turning off, the indoor fan motor
operates in the SUPER LOW position.
The pattern of operation depending on the relation
between room temperature and preset
temperatures is shown in Fig. 7-3-5.

Room temp.

Preset temp.+1

Preset temp.

Compressor

Outdoor fan

Indoor fan

ON ON ON ON

OFF OFF OFF

L. *S.L. S.L.L. L. S.L. L.

*Super Low

Fig. 7-3-5

(3) [FAN] button on the remote control is set to AUTO

only.

(4) The ECO operations can not be set.

(2) When [FAN] button is set to AUTO, the indoor fan

motor operates as shown in Fig. 7-3-7. When
[FAN] button is set to LOW, LOW+, MED, MED+ or
HIGH, the motor operates with a constant air flow.

Preset
temp.

°C

0

-0.5

-1

-1.5

-2

-5.0

-5.5

[FAN AUTO]

(Room temp.) − (Preset temp.)

L

*1
*2

*3

+

M

*1 : Fan speed = (M + − L) x 1/4 + L

*2 : Fan speed = (M + − L) x 2/4 + L
*3 : Fan speed = (M + − L) x 3/4 + L

(Calculated with Linear approximation from M+ and L)

Fig. 7-3-7

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17

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FILE NO. SVM-10035-1

y.

c

e

(3) The indoor heat exchanger restricts revolving

speed of the fan motor to prevent a cold draft. The
upper limit of the revolving speed is shown in
Fig. 7-3-8

Fan speed AUTO Fan speed MANUAL

46Tc34
45 33

33 21
32 20

*A+0 *A+0

*A-8 *A-8

Fan speed MANUAL or AUTO in starting
Fan speed AUTO in stability

* No limitation while fan speed MANUAL mode is in stabilit
* A: When Tsc 24, A is 24, and when Tsc < 24, A is Ts

Tsc: Set valu

Normal AUTO

Line-approximate
H and SL with Tc.

SL (W2)

Stop

L-H (Up to
setting speed)

Line-approximate
H and SL with Tc.

SL (W2)

Stop

[In starting and in stability]

In starting

FAN • Until 12 minutes

AUTO

passed after operation
start

• When 12 to 25 minutes
passed after operation

start and room temp.
is 3°C or lower than
set temp.

In stability

• When 12 to 25 minutes
passed after opeartion

start and room temp.
is than (set )

between preset

• When 25 minutes or
more passed after
operation start

3°C

7-3-5. Automatic operation

([MODE] button on the remote control is set
to the automatic operation.)

(1) One of 3 operations (Cooling, Fan only or Heating)

is selected according to difference between the
preset temperature and the room temperature at
which the automatic operation has started, as
shown in Fig. 7-3-9. The Fan only operation
continues until the room temperature reaches a
level at which another mode is selected.

(2) Temporary Auto

When the [RESET] button on the indoor unit

is pushed, the preset temperature is fixed at 24°C
and the indoor unit is controlled as shown in
Fig. 7-3-9.

°C

Cooling operation

0

Fan only operation

-1

Heating operation

(Room temp.) − (Preset temp.)

FAN • Room temp. < Set

Manual

temp.–4°C

• Room temp. Set
temp. –3.5°C

Fig. 7-3-8 Cold draft preventing control

(4) In order to prevent cold draft when compressor

during heating operation.Then louver will move
to upper position and fan speed will reduce or
OFF.

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18

Fig. 7-3-9

-

7-4. Drescription of Safety and Reliability Prevention Function

FILE NO. SVM-10035

7-4-1. Low-Temperature Limit Control

The microcontroller detects the indoor heat exchanger
temperature to prevent the indoor heat exchanger from
freezing.
The compressor and outdoor fan motor are controlled
as shown in Fig. 7-4-1.

Heat exchanger
temperature

(°C)

6

2

Compressor Outdoor fan

ON

Less than 2°C continues

for 5 minutes

OFF

Fig. 7-4-1

7-4-2 High-Temperature Limit Control

(Heat pump model only)

The microcontroller detects the indoor heat exchanger
temperature to prevent pressure of a refrigerating cycle
from increasing excessively.
The compressor and outdoor fan motor are controlled
as shown in Fig. 7-4-2.

7-4-3. Defrost Operation *Heat pump model only

When the indoor unit is in heating operation, if the
refrigerant evaporation temperature detected by the
outdoor heat exchanger sensor is under the specified
temperature, the outdoor unit starts the defrosting
operation. At this time, the 4-way valve relay and the
outdoor fan motor are turned off. The indoor fan motor
is also turned off by the cold draft preventing control of
the indoor microcomputer. Then, [PRE. DEF.] lamp on
the indoor unit comes on.
The defrosting operation stops and the 4-way valve
relay, outdoor fan motor and the indoor fan motor are
turned on automatically when the refrigerant
evaporation increases to the specified temperature, or
when the defrosting time is over 12 minutes.

7-4-3-1. Defrost starting condition

A-Zone : If -10°C > Teo ≥ − 18°C, defrost will

start when.
Teo - Te ≥ 2.5°C at teat 20 sec or

~ 30 min after operation.

B-Zone : If Te ≤ −18°C, defrost start instantaneously

(Suddenly) 00 ~ 25 min ofter operation

C-Zone : If -2ºC ≥ Teo ≥ −10°C defrost will start when

Teo - Te ≤ −3°C at least 20 sec or ~ 60 min
after operation.

Compressor

OFF

ON

ON

Outdoor fan

OFF

OFF

ON

Fig. 7-4-2

Heat exchanger
temp.

(°C)
62

55
54

7-4-3-2. Defrost finish condition.

1) If Te ≥ 3°C at least 60 sec -->4 way value on.

2) If Te ≥ 8°C --> 4 way value on.

Timing

Operation time (4 Loops = Tt)

Td1

Td2

Td3 Td4

Finish time recordStart time record

Defrost time rate : (Td/Tt) x 100
Heating time rate : (Tt - Td) x Tt

Fig. 7-4-3

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