Carrier 42NQ012N, 38NY012N Service Manual

SERVICE MANUAL

AIR-CONDITIONER

FILE NO. SVM-10031

SPLIT WALL TYPE

42NQ012N / 38NY012N

April, 2010

CONTENTS

1. SPECIFICATIONS

CONSTRUCTION VIEWS

2-1 Indoor Unit 2-2 Outdoor Unit

WIRING DIAGRAM

SPECIFICATION OF ELECTRICAL PARTS

5-1 Indoor Unit 5-2 Outdoor Unit

REFRIGERANT CYCLE DIAGRAM

CONTROL BLOCK DIAGRAM

OPERATION DESCRIPTION

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

7-3 Description of Operation Mode 7-4 Description of Safety and Reliability Prevention Function

7-5 Hi POWER operation 7-6 ECO operation 7-7 FILTER check lamp 7-8 Auto Restart Function

FILE NO. SVM-10031

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

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 9-6 Troubleshooting for Remote Control (Including The Indoor P.C. Board)

− 1 −

10. PARTS REPLACE THE MAIN PARTS

11-1 Indoor Unit 11-2 Microcomputer 11-3 Outdoor Unit

11. EXPLODED VIEWS AND PARTS LIST

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

11-3 Outdoor Unit 11-4 Outdoor Unit (E-Parts Assy)

FILE NO. SVM-10031

− 2 −

1. SPECIFICATIONS

FILE NO. SVM-10031

MODEL

ITEM

Capacity

Power source V 220 − 240

Power consumption kW Power factor % Running Indoor A 0.15 current Outdoor A 5.20 Starting current A 22 Moisture removal lit/h 2.0

Noise

Refrigerant

Refrigerant control

Interconnection pipe

Indoor (H/M/L) dB 42/39/36/34/32 Outdoor (220-240V) dB 50 51 50 Name of refrigerant Rated amount

Gas side size Connection type Flare connection Liquid side size mm ∅ 6.35 Connection type Flare connection

Maximum length (One way)

Maximum height difference

kW 3.70 3.74

Phase 1∅ 

Hz 50

220V

1.14 97

Cooling Heating

42NQ012N/38NY012N

240V 220V 240V

1.18 88

5.45

R410A

1.05

Capillary tube

∅ 12.7

15*

4.10 4.20

1.13 96

5.20

1.17 86

5.55

INDOOR UNIT

Height mm

Dimensions Width mm

Depth mm 205 Net weight kg 9 Evaporator type Finned tube Indoor fan type Cross flow fan

High fan m3/h 600

Airflow volume

Fan motor output W Air filter

OUTDOOR UNIT 38NY012N

Dimensions Width mm 780

Net weight Condenser type Finned tube Outdoor fan type Propeller fan Airflow volume m3/h 2120 2200 Fan motor output W

Compressor

Safety device Fuse, Overload relay Louver type Automatic louver Usable outdoor temperature range °C

Medium fan m3/h 430

Low fan m3/h 380

Active Carbon Cleaning filter

Height mm 550

Depth mm

Model PA145G1C-4FT1

Output W 1100

15 ~ 43 −10 ~ 24

42NQ012N

275 790

290

620 520

400

2120 2200

− 3 −

Note : 1

• Capacity is based on the following temperature conditions.

FILE NO. SVM-10031

Temperature

Indoor unit inlet air temperature

Outdoor unit inlet air temperature

Note : 2

*1 No need to charge extra refrigerant.

Condition

Cooling Heating

(DB) 27°C 20°C

(WB) 19°C 15°C

(DB) 35°C 7°C

(WB) 24°C 6°C

JIS C9612

− 4 −

2-1. Indoor Unit

FILE NO. SVM-10031

2.CONSTRUCTION VIEWS

Front panel

Knock out system

Air inlet

275

116

Installation plate hanger

Air filter

790

Heat exchanger

205

65 6

Knock out system

193480

Installation plate hanger

Connecting pipe (0.35m)

(Flare ∅12.70mm)

84.5

Minimum

distance

to wall

275

170 or more

Hanger

84.5 150 84.5

621

235

215

Hanger

Minimum

distance

to ceiling

235

215

160.5 160.5 150

Center line

Drain hose (0.50m)

Connecting pipe (0.40m)

6.35mm)(Flare

84.5

65 or more

Minimum

distance

to wall

170 or more

Hanger

Installation plate outline

Wireless remote controller

Remote controller holder

190

157

125

− 5 −

2.2. Outdoor Unit

600

320

306

A detail Drawing (Back leg)

R5.5

6 hole

320

25 Drain outlet

FAN-GUARD

436

FILE NO. SVM-10031

108 125

306

320

11 x 14

(For 8 -

Hole

10 anchor bolt)

6 hole

11x14 hole

B Detail Drawing (Front leg)

36 50

COVER-PV

290

550

275

320 342

Electrical part cover

Liquid side (Flare 6.35)

Gas side (Flare 12.7)

ervice port

Z View

9060090

129

100 or more

320

100 or more

Air outlel

600

Air intlel

600 or more

− 6 −

600 or more

4x 11 Long holes(For 8- 10 anchor bolt)

3. WIRING DIAGRAM

FILE NO. SVM-10031

OUTDOOR TERMINAL BLOCK

COMPRESSOR

BLK

PNK

PNK WHI

WHI

(L)2(N)

(L)

RED

(N)

BLU

SOLENOID COIL

CAPACITOR

RED

CAPACITOR

313

BLU

FAN

FAN MOTOR

MOTOR

− 7 −

WHI

CHASSIS

BLK

OUTDOOR

4-1. Indoor Unit

FILE NO. SVM-10031

4. SPECIFICATION OF ELECTRICAL PARTS

No.

1 Fan motor (for indoor) AFN-220-20-4D AC Motor with 145 C thermo fuse 2 Thermo sensor (TA-sensor) 10k at 25 C 3 Power Module (M01) 4 Microcontroller unit (IC30) TMP87CM40ANG-6P68 5 Heat exchanger sensor

(TC-sensor) 6 Line filter (L01) LC*SS11V-R06270 27mH, 600mA 7 Bridge diode (DB01) DB105G 1A, 600 V 8 Capacitor (C03) 9 Fuse (F01) BET 6.3A T6.3A, 250VAC

10 Varistor (R06, R07) SR561K14DO 560 V 11 Resistor (R01 ) RF-2TK5R6 5.6 , 2 W 12 Louver motor MP24Z3T 12VDC 13 Relay (Comp., RY01) G4A-1A-E-CA Rating 20A/AC250 V, 12VDC 14 Relay (Fan, RY03) 15 Relay (Solenoide, RY04) Rating 3A/A

Parts name Type Specifications

GPS-9W-AA

400MXC47MEFCSN20X20

202N-1AC-C E

Rating 3A/A V, 12VDC

DC370V, Secondary DC13V

10k at 25 C

47mF, 400 V

C240 C240

V, 12VDC

4-2. Outdoor Unit

No. Parts name

1 Compressor PA145G1C-4FT1 Winding resistance (Ω) C-R C-S

Fan motor

(for outdoor)

Running capacitor

(for fan motor) Running capacitor

(for compressor) Solenoid coil

(for 4-way valve)

(for Heat pump

model)

B32332I5306J063

Type

Output (Rated) 1100W, 2poles, 1 phase, 220 − 240V, 50Hz

(at 20°C) 2.67 4.48 Output (Rated) 42W, 6poles, 1 phase, 220 − 240V, 50Hz

WLF-240-42A

DS451155NPQB AC 450V, 1.5µF

STF-01AJ503H1

Winding resistance (Ω) Red-Black White-Black (at 20°C)

AC 450V, 30µF

AC 220 − 240V, 50Hz

Specifications

188

289

− 8 −

5. REFRIGERATION CYCLE DIAGRAM

FILE NO. SVM-10031

Indoor unit

Cooling

0.39m (Connecting pipe) ∅12.7

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

Cooling

Heating

Packed valve

(∅12.7)

Heating

4-way valve

Cooling

Compressor

PA145G1C-4FT1

Accumulator

Heat exchanger

Cross flow fan

Capillary tube

∅1.5x1500l

0.49m (Connecting pipe)

∅6.35

Packed valve

(∅6.35)

Capillary tube

∅1.2x500l

Heat exchanger

Refrigerant R410A : 1.05 kg.

Cooling Heating

Propeller fan Outdoor unit

Mark( )means check points of Gas Leak.

Ambient temp.

50Hz

Standard

pressure

(MPaG)

Surface temp. of heat

exchanger interchanging

pipe

(°C)

Fan speed

(indoor)

conditions DB/WB

(°C)

Indoor Outdoor

Standard 2.72 46.9 High 20/15 7/6

Heating Overload*1

3.70

59.9

Low

27/− 24/18

Low temperature 2.51 37.2 High 20/−−10/−10 Standard 0.91

9.5

High

27/19

35/24

Cooling Overload 1.26 14.6 High 32/23 43/26

Low temperature 0.77 1.5 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 −

6. CONTROL BLOCK DIAGRAM

FILE NO. SVM-10031

Heat Exchange sensor

Thermo. Sensor

Current Sensor

(Compressor Current)

Infrared Rays Signal Reciver

Main Unit Control Panel

Functions

• Louver Control

•3-minutes Delay at Restart

for Compressor

Initiallizing Circuit

Clock Frequency Oscillator Circuit

Power Supply

Circuit

Noise Filter Relay Driver, Louver Driver

•Motor Revolution Control

•Processing

(Temperature Processing)

•Timer

Compressor

ON/OFF

Signal

Outdoor Fan

Relay

RY01

M.C.U.

ON/OFF

Signal

Relay

4-Way Valve

ON/OFF

Signal

RY03

Operation

Display

Timer

Display

Filter Sign

Display

Hi Power

Sign Display

PRE DEF.

Sign Display

Indoor Fan

Motor

Louver

ON/OFF

Signal

Louver

Motor

Relay

RY04

220-240 V~, 50Hz

REMOTE CONTROL

Operation Mode Selection

AUTO, COOL, DRY, HEAT, FAN ONLY

Compressor 4-Way Valve

Remote Control

Operation ( )

Temperature Setting Fan Speed Selection

ON TIMER Setting

OFF TIMER Setting

Louver Auto Swing

Louver Direction Setting

ECO

Hi power

TIMER 1.3.5.9H

COMFORT SLEEP

QUIET

Outdoor Fan Motor

Infrared Rays

− 10 −

7. OPERATION DESCRIPTION

FILE NO. SVM-10031

7-1. Remote control

7-1-1. Remote control and its functions

Infrared signal emitter

1 2

Start/Stop button ( ) Mode select button ( )

Temperature button ( )

Fan speed button ( )

Swing louver button ( )

Set louver button ( )

On timer button ( )

Off timer button ( )

Sleep timer button ( )

Setup button ( )

Clear button ( )

Memory and Preset button ( )

High power button ( )

Economy button ( )

Filter reset button ( )

Clock reset button ( )

Check button ( )

OFF

18 16

PRESET

ON OFF

SLEEP

CHECK FILTER CLECK

HI-POWER

FAN

MODE

ECOFIXSWING

CLR

SET

5 4

14 15

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

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 −

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).

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

FILE NO. SVM-10031

Press : Set the desired ON timer.

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

Press : Cancel the timer. Press

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

Press

: Set the ON timer.

Press .

Press

OF F

: Set the OFF timer.

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

Press button during the ( or )

mark flashing.

( or )

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-10031

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-10031

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

Transmission mark

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

Mode indicator

Indicates the current operation mode. (A :

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

Temperature indicator

Indicates the temperature setting.

ºC ºC

(17 to 30 )

FAN speed indicator

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

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

The current time is always indicated except during TIMER operation.

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.

(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

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

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.)

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.

– 14 –

FILE NO. SVM-10031

7-2. Outline of Air Conditioner Control

This is a fixed capacity type air conditioner, which uses a AC motor for an indoor fan. The AC 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 controller. 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

• Defrost control in heating operation (Temperature measurement by the indoor heat exchanger and control for the four-way valve and the outdoor fan motor) *Heat pump Model only

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 5 stages in MANUAL model, and in 5 stages in AUTO mode, respectively. (Table 7-2-1)

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

Fig (7-2-1) Cooling Fig (7-2-2) Heating

Indication

L L+

M M+

Fan speed

Low

(L + M) / 2

Med

(M + H) / 2

High

Indication

L L+

M M+

Fan speed

(L + M) / 2

(M + H) / 2

Low

Med

High

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

Cooling Fan onlyOPERATION

MODE

Fan speed (rpm)

Air flow volume (m3/h)

Dry Heat

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 7-2-1 according to the setup temperature, room temperature, and heat exchanger temperature.

FAN TAP

L L- SL

UH H

M+

1300

620

M+ M+

H M L L-

M+

1250

1150 110

600

550 520

L+

1000

430

L+ L+

L+

850

400 240

400

L-

L L- UL

800 750 650

380 350 310

− 15 −

UL SL

600 280

260

500550

FILE NO. SVM-10031

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 [ ] 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 [ ] 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, LOW+, MED, 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

Fig. 7-3-2

display lamp

OPERATION

(Room temp.) − (Preset temp.)

Preset temp.

+3 +2.5 +2

+1.5 +1 +0.5 0

(Preset temp.: 24 °C)

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)

NOTE2 : The Hi Power, ECO and COMFORT SLEEP

operation can not be set

Fig. 7-3-1

(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, LOW+, MED, 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

-0.5

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)

Fig. 7-3-3

− 16 −

FILE NO. SVM-10031

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:5min.

OFF:5min.

OFF

4-way valve

Outdoor fan

(Room temp.) (Preset temp.)

Preset temp.

ON:6min.

OFF:4min.

OFF

ON:5min.

OFF:5min.

OFF

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

0.5

(Room temp.) (Preset temp.)

OFF

Compressor

OFF

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 and Hi Power 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

-0.5

-1

-1.5

-2

-5.0

-5.5

[FAN AUTO]

(Room temp.) − (Preset temp.)

*1 *2

*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 inear approximation from M+ and L+)

Fig. 7-3-7

− 17 −

FILE NO. SVM-10031

(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 and Table 7-3-9.

T 46 46 45 45 33

33 33 21 32 32 20

*A+4 *A+4 *A+4

*A-4 *A-4 *A-4

* 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

Fan speed MAN Fan speed AUTO in stabilit Fan speed AUTO in startin

Line-approximate H and S

SUL

L with Tc

Stop

AL in startin

Fig. 7-3-9 Cold draft preventing control

Table 7-3-8

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. 7-3-10. 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. 7-3-10

°C

Cooling operation

(Preset temp.)

−

-1

Fan only operation

Fan *5 *6 speed Starting period Stabilized period

AUTO • Up until 12 minutes

passed after starting the unit

• From 12 to 25 minutes passed after starting the unit and room temperature is 3°C lower than preset temperature

Manual • Room temperature (L – H) < Preset temperature

• From 12 to 25 minutes passed after starting the unit and room temperature is between preset temperature and 3°C lower than preset temperature

• 25 minutes or more passed after starting the unit

• Room temperature

Preset temperature

–4°C

–3.5°C

Heating operation

(Room temp.)

Fig. 7-3-9

− 18 −

7-4. Description of Safety and Reliability Prevention Function

FILE NO. SVM-10031

7-4-1. High-Temperature Limit Control

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. 7-4-1.

Compressor

OFF

Outdoor fan

OFF

Heat exchanger temp.

(°C) 60

53 52

Fig. 7-4-1

7-4-2. 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. 7-4-2

7-4-3. Defrost Operation

During the heating operation, the outdoor heat exchanger temperature goes down and sometimes it is frozen. In this case, the air conditioner stops the heating operation and starts the defrost operation to melt ice.

Condition to start the defrost operation

The defrost operation starts whichever below conditions are satisfied.

(1) When the cumulative compressor operating time is

longer than 40 or 90 minutes and difference between the indoor heat exchanger temperature and the room temperature is less than the specified value. (This value is decided by the microprocessor.) (Control example is shown in Fig. starts.)

(2) When the current limit control or the high

temperature limit control is performed for total of 90 minutes.

In case of B or C, the defrost operation

7-4-3.

Heat exchanger temperature

(°C)

Compressor Outdoor fan

Fig. 7-4-2

Less than 5°C continues

for 5 minutes

OFF

xchanger temp

Indoor heat e

- Room temp

Fig. 7-4-3 (Indoor fan speed : M)

Defrost operation time control <In case of B>

(1) The heating operation is performed for at least

40 minutes.

(2) The maximum defrost operating time is 6 minutes.

The defrost operating time for the 4th cycle is 10 minutes. (When the outdoor temperature is very low, however, the defrost operating time is 10 minutes.)

Cumulative compressor operating time

− 19 −

FILE NO. SVM-10031

minutes

Heating

minutes

Defrost

Heating

Max 6 minutes

minutes

Defrost

1 cycle

Heating

10 minutes

minutes

Defrost

Heating

Defrost

Fig. 7-4-4

(1) The heating operation is performed for at least 90

minutes.

(2) The defrost operating time is 10 minutes.

Ending condition at defrost operation

(1) When the compressor current becomes 5.10A or

more during defrost operation, the defrost operation stops and the heating operation restarts. (The current sensor detects the compressor current.)

(2) The defrost operation continues for at most

6 minutes or 10 minutes.

DEFROST LAMP :

During defrost operation, the PRE-DEF. lamp is on and the indoor and outdoor fans are off.

The compressor start protection timer is interlooked with the PRE-DEF. lamp. So the PRE-DEF. Lamp is off (the fans stop) for about 3 minutes after the [ ] button is turned on. When the compressor is turned on, the PRE-DEF. lamp comes on. After the heat ex-changer is preheated to about 24 goes off, and the indoor fan starts.

°C or higher

, the PRE-DEF. Lamp

− 20 −

+ 47 hidden pages

Carrier 42NQ012N, 38NY012N Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual