LG SVC Schematic

Air Conditioner

SVC MANUAL(General)

CAUTION

Before Servicing the unit, read the safety precautions in General SVC manual. Only for authorized service personnel.

Internal Use Only

http://biz.lgservice.com

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LGE Internal Use Only

Air Conditioner Service Manual

TABLE OF CONTENTS

Part 1 General Information ..........................................................................................................3

1. Safety Precautions........................................................................................................4

2. Model Line Up................................................................................................................7

3. Nomenclature ................................................................................................................8

Part 2 Functions & Controls......................................................................................................10

1. List of Functions & Accessory...................................................................................11

2. Air flow ........................................................................................................................14

3. Air purifying.................................................................................................................16

4. Installation Functions.................................................................................................17

5. Reliability .....................................................................................................................21

6. Convenience Functions & Controls .........................................................................22

7. Special Function & KIT...............................................................................................32

Part 3 Basic Control ..................................................................................................................35

1. Normal operation ........................................................................................................36

2 Compressor control ....................................................................................................36

3. EEV( Electronic Expansion Valve) control ...............................................................36

Part 4 Trouble Shooting ...........................................................................................................37

1. Self-diagnosis Function ............................................................................................38

2. Pump Down ................................................................................................................40

3. Evacuation (All amount of refrigerant leaked) ........................................................41

4. Gas Charging (After Evacuation)..............................................................................42

5. Cycle Part....................................................................................................................43

6. Electronic Parts..........................................................................................................44

Part 1 General Information

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LGE Internal Use Only

1. Safety Precautions ............................................................................................................4

2. Model Line Up .....................................................................................................................7

3. Nomenclature......................................................................................................................8

Part 1 General Information

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LGE Internal Use Only

1. Safety Precautions

1.1 Cautions in Repair

To prevent injury to the user or other people and property damage, the following instructions must be followed.

n Incorrect operation due to ignoring instruction will cause harm or damage. The seriousness is classified by the follow-

ing indications.

This symbol indicates the possibility of death or serious injury.

This symbol indicates the possibility of injury or damage to properties only.

n Meanings of symbols used in this manual are as shown below.

Be sure not to do.

Be sure to follow the instruction.

Dangerous Voltage

Be sure to disconnect the power cable plug from the plug socket before disassembling the equipment for a repair.Internal components and circuit boards are at main potential when the equipment is connected to the power cables. This voltage is extremely dangerous and may cause death or severe injury if come in contact with it.

Do not touch the discharging refrigerant gas during the repair work. The discharging refrigerant gas.The refrigerant gas can cause frostbite.

Release the refrigerant gas completely at a well-ventilated place first. Otherwise, when the pipe is disconnected, refrigerant gas or refrigerating machine oil discharges and it Can cause injury.

When the refrigerant gas leaks during work, execute ventilation. If the refrigerant gas touches to a fire, poisonous gas generates. A case of leakage of the refrigerant and the closed room full with gas is dangerous because a shortage of oxygen occurs. Be sure to execute ventilation.

When removing the front panel or cabinet, execute short-circuit and discharge between high voltage capacitor terminals. If discharge is not executed, an electric shock is caused by high voltage resulted in a death or injury.

Do not turn the air-conditioner ON or OFF by plugging or unplugging the power plug. There is risk of fire or electrical shock.

Part 1 General Information

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LGE Internal Use Only

Do not turn on the breaker under condition that front panel and cabinet are removed.

Be sure to earth the air conditioner with an earthing conductor connected to the earthing terminal.

Conduct repair works after checking that the refrigerating cycle section has cooled down sufficiently. Otherwise, working on the unit, the hot refrigerating cycle section can cause burns.

Do not tilt the unit when removing panels. Otherwise, the water inside the unit can spill and wet floor.

Do not use the welder in a well-ventilated place. Using the welder in an enclosed room can cause oxygen deficiency.

Be sure to turn off power switch before connect or disconnect connector, or parts damage may be occurred.

Do not use a defective or underrated circuit breaker. Use the correctly rated breaker and fuse. Otherwise there is a risk of fire or electric shock.

Install the panel and the cover of control box securely. Otherwise there is risk of fire or electric shock due to dust, water etc.

Indoor/outdoor wiring connections must be secured tightly and the cable should be routed properly so that there is no force pulling the cable from the connection terminals. Improper or loose connections can cause heat generation or fire.

Do not touch, operate, or repaire the product with wet hands. Hoding the plug by hand when taking out. Otherwise there is risk of electric shock or fire.

Use a vacuum pump or Inert (nitrogen) gas when doing leakage test or air purge. Do not compress air or Oxygen and Do not use Flammable gases. Otherwise, it may cause fire or explosion.

- There is the risk of death, injury, fire or explosion.

Part 1 General Information

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LGE Internal Use Only

1.2 Inspections after Repair

Check to see if the parts are mounted correctly and wires are connected. Improper installation and connections can cause an electric shock or an injury.

Check the installation platform or frame has corroded. Corroded installation platform or frame can cause the unit to fall, resulting in injury.

Be sure to check the earth wire is correctly connected.

After the work has finished, be sure to do an insulation tset to check the resistance is 2[Mohm] or more between the charge section and the non-charge metal section (Earth position). If the resistance value is low, a disaster such as a leak or electric shock is caused at userʼs side.

Check the drainage of the indoor unit after the repair. If drainage is faulty the water to enter the room and wet floor.

Check to see if the power cable plug is not dirty or loose. If the plug is dust or loose it can cause an electrical shock or fire.

Do not use a joined power cable or extension cable, or share the same power outlet with other electrical appliances. otherwise, it can cause an electrical shock, excessive heat generation or fire.

Do not insert hands or other objects through the air inlet or outlet while the product is operating. There are sharp and moving parts that could cause personal injury.

Do not block the inlet or outlet of air flow. It may cause product failure

Category

Chassis

Name

Capacity Index[kBtu/h]

18 24 36 42

Ceiling

Conceal

ed Duct

High

Static

Pressur

BG

BR

Ceiling

Cassette

4way

TP

TM

Part 1 General Information

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LGE Internal Use Only

2. Model Line Up

2.1 Indoor units

2.2 Outdoor units

DC Inverter

AUUW18GD2

[LUU187HV]

AUUW24GD2

[LUU247HV]

AUUW36GD2

[LUU367HV]

AUUW42GD2

[LUU427HV]

No. of connectable

indoor units

1

Total Capacity index of

conectable indoor

units(kBtu)

18 24 36 42

Power supply

1Ø, 203-230V, 60Hz

Chassis

ABNH24GGLA2

[LHN240HV]

ATNH18GPLE2

[LCN187HV]

ATNH24GPLE2

[LCN247HV]

ATNH36GMLE2

[LCN367HV]

ATNH42GMLE2

[LCN427HV]

ABNH36GRLA2

[LHN360HV]

Part 1 General Information

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LGE Internal Use Only

3. Nomenclature

3.1 Indoor Unit(Global)

Indoor Unit (Buyer)

Serial number

Function A : Basic, C/L : Plasma, E : Elevation grille

Panel Color for ART COOL V: Silver, G : Gold, H : White Silver, E : Red, 1 : Gallery

Panel Color for ARTCOO Mirror R : Mirror, V : Silver, W : White

Look L : Basic

Chassis name G : BG R : BR P : TP M : TM

Electrical rating G: 1Ø, 220-240V, 50Hz / 1Ø, 220V, 60Hz

Nominal Capacity Ex) 24,000 Btu/h Class → '24',

36,000 Btu/h Class → '36' Model type W/H : DC Inverter Heat pump

A*N / U*N : Indoor units using R410A * Indicates Product type

M : Only for Multi systems T : Ceiling Cassette

B : Ceiling Concealed Duct V : Ceiling Suspended & floor Q : Console

ABN H G24 LGA2

Nominal Capacity Ex) 24,000 Btu/h Class → '24',

36,000 Btu/h Class → '36'

L H N 024 H V

Inverter

Serial number

Indoor unit

Indoor unit type H : High static Duct C : Cassette

Heat Pump

Part 1 General Information

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LGE Internal Use Only

G

A U U W 2 4 D2

Model Type

D : Standard Inverter

Electric standard (Phase, Volts, Freq)

G: 1Ø, 220-240V, 50Hz / 1Ø, 220V, 60Hz 6:1Ø,220V-240V,50Hz 8:3Ø,380V-415V,50Hz

Serial number

Indicates that this is a

R410A outdoor unit

Model type

W : Inverter heat pump

Nominal cooling capacity in kBtu/h

18 : 24 : 30 : 36 : 42 : 48 : 60 :

18kBtu/h 24kBtu/h 30kBtu/h 36kBtu/h 42kBtu/h 48kBtu/h 60kBtu/h

Nominal Capacity Ex) 24,000 Btu/h Class → '24',

36,000 Btu/h Class → '36'

L U U 024 H V

Inverter

Serial number

Outdoor unit

Brand (LG)

Outdoor unit type Universal

Heat Pump

3.2 Outdoor Unit(Global)

Outdoor Unit (Buyer)

Part 2 Functions & Controls

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LGE Internal Use Only

Part 2 Functions & Controls

1. List of Functions & Accessory ......................................................................................11

1. Ceiling Concealed Duct Indoor......................................................................................11

2. 4-Way Ceiling Cassette Indoor .....................................................................................12

3. Outdoor .........................................................................................................................13

2. Air flow ...........................................................................................................................14

2.1 Auto swing (left & right)...............................................................................................14

2.2 Auto swing (up & down) ..............................................................................................14

2.3 Chaos swing (up/down)...............................................................................................14

2.4 Air flow step.................................................................................................................15

2.5 Chaos wind (auto wind)...............................................................................................15

2.6 Jet Cool Mode Operation ............................................................................................15

2.7 Swirl wind Swing .........................................................................................................15

3. Air purifying ....................................................................................................................16

3.1 PLASMA Air Purifying System ....................................................................................16

4. Installation Functions ....................................................................................................17

4.1 E.S.P. (External Static Pressure) Setting (DUCT).......................................................17

4.2 E.S.P. (External Static Pressure) Setting (Cassette)...................................................19

5. Reliability ........................................................................................................................21

5.1 Hot start.......................................................................................................................21

5.2 Self-diagnosis Function...............................................................................................21

5.3 Soft dry operation........................................................................................................21

6. Convenience Functions & Controls .............................................................................22

6.1 Cooling & heating Operations .....................................................................................22

6.2 Auto cleaning operation ..............................................................................................23

6.3 Auto changeover operation.........................................................................................23

6.4 Auto restart Opeartion.................................................................................................23

6.5 Child Lock Function.....................................................................................................24

6.6 Forced operation.........................................................................................................25

6.7 Group Control..............................................................................................................26

6.8 Sleep Timer Operation................................................................................................27

6.9 Timer(On/Off) ..............................................................................................................27

6.10 Weekly Program........................................................................................................28

6.11 Two Thermistor Control .............................................................................................30

7. Special Function.............................................................................................................32

7.1 Low Ambient control...................................................................................................32

7.2 Space control ..............................................................................................................32

7.3 Auto Elevation Grille....................................................................................................32

Part 2 Functions & Controls

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LGE Internal Use Only

1. List of Functions & Accessory

1. Ceiling Concealed Duct Indoor

Category Functions Remark

Air flow

Air supply outlet 1 Airflow direction control (left & right) X Airflow direction control (up & down) X Auto swing (left & right) X Auto swing (up & down) X Airflow steps (fan/cool/heat) 3 / 3 / 3 Chaos wind(auto wind) X Jet cool/heat X / X Swirl wind X

Air purifying

Triple filter (Deodorizing) X Plasma air purifier X Allergy Safe filter X Long-life prefilter (washable / anti-fungus) X

Installation

Drain pump O E.S.P. control O Electric heater X High ceiling operation X Auto Elevation Grille X

Reliability

Hot start O Self diagnosis O Soft dry operation O

Convenience

Auto changeover O Auto cleaning X Auto operation(artificial intelligence) X Auto Restart O Child lock O Forced operation X Group control O Sleep mode O Timer(on/off) O Timer(weekly) O Two thermistor control O

Individual

control

Standard Wired remote controller

PQRCVSL0/PQRCVSL0QW Deluxe wired remote controller X Simple wired remote controller O Simple Wired remote controller(for hotel use) X Wireless remote controller X

Network

function

General central controller (Non LGAP) X Network Solution(LGAP) O Dry contact

PQDSA(1) / PQDSB(1) / PQDSBC

PI 485(for Indoor Unit) X

Special

function kit

Zone controller ABZCA CTI(Communication transfer interface) X Electronic thermostat X

Others Remote temperature sensor PQRSTA0

Part 2 Functions & Controls

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LGE Internal Use Only

Air supply outlet 4 Airflow direction control(left & right) Airflow direction control(up & down) Auto Auto swing(left & right) X Auto swing(up & down) O Airflow steps(fan/cool/heat) 4 / 5 / 4 Chaos swing X Chaos wind(auto wind) Jet cool(Power wind) O Swirl wind O Deodorizing filter Plasma air purifier PTPKM0 Prefilter(washable / anti-fungus) O Drain pump O E.S.P. control O Electric heater(operation) High ceiling operation O Hot start O Self diagnosis O Soft dry operation O Auto changeover O Auto cleaning X Auto operation(artificial intelligence) X Auto restart operation O Child lock O Forced operation O Group control O Sleep mode O Timer(on/off) O Timer(weekly) O Two thermistor control O Standard wired remote controller PCRCUSZ0 Picto wired remote controller PQRCUSA1 Deluxe wired remote controller PQRCUDS0 Simple wired remote controller PQRCUCA0 Wired remote controller(for hotel use) PQRCFCS0 Wireless remote controller(simple) X Wireless LCD remote control PQWRHSF0(H/P) PQWRHDF0(H/P) General central controller (Non LGAP) X Dry contact PQDSB Network Soluation(LGAP) O PDI(power distribution indicator) X PI 485 PSNFP14A0 Zone control X CTIE X Electro thermostat X Thermistor Home net Support -

Category Function Remark

Air flow

Air purifying

Reliability

Individual

control

Convenience

Installation

CAC network

function

Special

function kit

Others

2. 4-Way Ceiling Cassette Indoor

Part 2 Functions & Controls

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LGE Internal Use Only

3. Outdoor

Category Functions

AUUW18GD2

[LUU187HV]

AUUW24GD2

[LUU247HV]

AUUW36GD2

[LUU367HV]

AUUW42GD2

[LUU427HV]

Reliability

Defrost / Deicing OOOO High pressure switch X X X X Low pressure switch X X X X Phase protection X X X X Restart delay (3-minutes) OOOO Release Control OOOO Self diagnosis OOOO Soft start OOOO

Test function OOOO Convenience Night Silent Operation OOOO CAC network function

Network soluation(LGAP) OOOO

`

Device

AUUW18GD2

[LUU187HV]

AUUW24GD2

[LUU247HV]

AUUW36GD2

[LUU367HV]

AUUW42GD2

[LUU427HV]

Central Controller

Simple Controller PQCSB101S0 PQCSB101S0 PQCSB101S0 PQCSB101S0

Function controller

PQCSB101S0 + PQCSC101S0 PQCSB101S0 + PQCSC101S0 PQCSB101S0 + PQCSC101S0 PQCSB101S0 + PQCSC101S0

Function Scheduler

PQCSB101S0 + PQCSD130A0 PQCSB101S0 + PQCSD130A0 PQCSB101S0 + PQCSD130A0 PQCSB101S0 + PQCSD130A0 AC Ez PQCSZ250S0 PQCSZ250S0 PQCSZ250S0 PQCSZ250S0 AC Smart ll PQCSW320A1E PQCSW320A1E PQCSW320A1E PQCSW320A1E Option Kit (SD card type)

PQCSE341A0 / PQCSE342A0 PQCSE341A0 / PQCSE342A0 PQCSE341A0 / PQCSE342A0 PQCSE341A0 / PQCSE342A0 ACP(Advanced Control Platform)

PQCPA11A0E /

PQCPB11A0E

PQCPA11A0E /

PQCPB11A0E

PQCPA11A0E /

PQCPB11A0E

PQCPA11A0E /

PQCPB11A0E

AC Manager PQCSS520A0E PQCSS520A0E PQCSS520A0E PQCSS520A0E PI485 PMNFP14A0/PMNFP14A1 PMNFP14A0/PMNFP14A1 PMNFP14A0/PMNFP14A1 PMNFP14A0/PMNFP14A1 DO(Digital Output) Kit PQNFP00T0 PQNFP00T0 PQNFP00T0 PQNFP00T0

BNU (Building Network Unit)

LONWORKS Gateway PQNFB16A1 PQNFB16A1 PQNFB16A1 PQNFB16A1 BACnet Gateway PQNFB17B0 PQNFB17B0 PQNFB17B0 PQNFB17B0

Installation

Y branch X X X X Header branch X X X X Air Guide X X X X

ODU Dry Contact X X X X Low Ambient Kit O (Logical operation) O (Logical operation) O (Logical operation) O (Logical operation)

Part 2 Functions & Controls

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LGE Internal Use Only

2. Air flow

2.1 Auto swing (left & right)

• By the horizontal airflow direction control key input, the left/right louver automatically operates with the auto swing or it is fixed to the desired direction.

2.2 Auto swing (up & down)

• By the auto swing key input, the upper/lower vane automatically operates with the auto swing or it is fixed to the desired direction.

2.3 Chaos swing (up/down)

• By the Chaos swing key input, the upper/lower vane automatically operates with the chaos swing or it is fixed to the desired direction.

RightLeft

110° ~ 120°

Close

110° ~ 120°

Open

CLOSED

Mode9

Mode8

Mode7

Mode6

Mode5

Mode4

Mode3

Mode2

110~120°

7~8°

OPEN

Part 2 Functions & Controls

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LGE Internal Use Only

NOTE: Some Models are different by swing width and swing pattern.

2.4 Air flow step

• Indoor fan motor control have 6 steps.

• Air volume is controlled "SH", "H", "Med", Low" by remote controller.

• "LL" step is selected automatically in Hot start operation.

2.5 Chaos wind (auto wind)

• When "Auto" step selected and then operated, the high, medium, or low speed of the airflow mode is operated for 2~15 sec. randomly by the Chaos Simulation

2.6 Jet Cool Mode Operation

• While in heating mode or Fuzzy operation, the Jet Cool key cannot be input. When it is input while in the other mode operation (cooling, dehumidification, ventilation), the Jet Cool mode is operated.

• In the Jet Cool mode, the indoor fan is operated at super-high speed for 30 min. at cooling mode operation.

• In the Jet Cool mode operation, the room temperature is controlled to the setting temperature, 18°C.

• When the sleep timer mode is input while in the Jet Cool mode operation, the Jet Cool mode has the priority.

• When the Jet Cool key is input, the upper/lower vanes are reset to those of the initial cooling mode and then operated in order that the air outflow could reach further.

2.7 Swirl wind Swing

• It is the function for comfort cooling/heating operation.

• The diagonal two louvers are opened the more larger than the other louvers. After one minute, it is opposite.

• Comparison of Air Flow Types

4-Open (conventional) Swirl Swing (New)

LL Very low, In heating mode

L Low

M Med

H High

SH Super high

Auto Chaos wind

Step Discription

Vane 4

Vane 2

Vane 1 Vane 3

Part 2 Functions & Controls

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LGE Internal Use Only

3.1 PLASMA Air Purifying System (Optional)

The PLASMA Air Purifying System not only removes microscopic contaminants and dust, but also removes house mites, pollen, and pet fur to help prevent allergic diseases like asthma. This filter that can be used over and over again by simply washing with water.

3. Air purifying

Ionizer

Photo-Catalyst Coated Mesh

Dust particles

Odour

Dust electrode discharge

Odour molecule

Generating plasma

+

Polluted Air

Purified fresh Air

+4.8KV discharge

+

Part 2 Functions & Controls

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LGE Internal Use Only

4.1 E.S.P. (External Static Pressure) Setting (DUCT)

4. Installation Functions

This is the function that decides the strength of the wind for each wind level and because this function is to make the installation easier.

• If you set ESP incorrectly, the air conditioner may malfunction.

• This setting must be carried out by a certificated-technician.

• Precaution shall be taken not to alter the E.S.P value corresponded to each air flow section.

• E.S.P value can be varied according to the products.

• In the case of going to the next air flow rate stage by pressing the fan-speed button during the setup of the E.S.P value, the E.S.P value of previous air flow rate will be maintained by remembering the E.S.P value prior to the shift.

TEMP

FAN

SPEED

OPER MODE

When pressing the button and

1

button simultaneously for more than 3 seconds, the system will be entered into the installer setting mode.

- After entering into the installer setting mode, select the E.S.P code value by pressing the button.

* E.S.P code value : 03

Select the desired air flow rate with

2

3

4

5

FAN

SPEED

the button. Whenever pressing

FAN

the button, [SLo→Lo→Med→Hi→Po] will

SPEED

be indicated.

Select the desired air flow rate value with the temperature up(s), down(t) button. * E.S.P value range : 0~255

-

E.S.P value will be indicated at the upper

right section of the display window.

When pressing the button, currently established E.S.P value will be set up.

When pressing the button and button simultaneously for more than 3 seconds after the setting has been completed, the setting mode will be released.

- If there isn’t any button input for more than

25 seconds, the installer setting mode will also be released.

OPER MODE

Part 2 Functions & Controls

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LGE Internal Use Only

E.S.P. setting value (reference)

[ Notes ]

1. To get the desired Airflow & E.S.P. combination from the table set the matching value from the table. Value other than that in table will not give the combinations of airflow & E.S.P. which are mentioned in the table.

2. Table data is based at 230V. According to the fluctuation of voltage, air flow rate varies.

Table 1

Capacity Step CFM

Static Pressure(Pa)

24.5 39.2 58.8 78.4 98

Setting Value

24K

HIGH 688 900 970 1080 1190 1260

MID 600 860 930 1050 1150 1230

LOW 565 820 900 1020 1120 1200

36K

HIGH 1130 - 960 1030 1090 1150

MID 950 - 850 960 1020 1090

LOW 706 - 760 850 950 1000

Part 2 Functions & Controls

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LGE Internal Use Only

4.2 E.S.P. (External Static Pressure) Setting (Cassette)

This function is applied to only duct type. Setting this in other cases will cause malfunction.

Pressure selection

Function

Zone state ESP standard value 01 V-H Variable High 02 F-H Fixed High 03 V-L Variable Low 04 F-L Fixed Low

Press button for 4 seconds to enter the installer

1

setting mode until timer segment displays “01:01”.

If pressing button repeatedly, it moves to static pressure

2

selection menu as picture below.

Select static pressure by pressing button.

3

(01:V-H, 02:F-H, 03:V-L, 04:F-L)

Function Code Pressure

Press button to save.

4

Pressing button will exit settings mode.

5

❈ After setup, it automatically gets out of setup mode if there is no button

input for 25 seconds.

❈ When exiting without pressing set button, the manipulated value is not

reflected.

Part 2 Functions & Controls

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LGE Internal Use Only

If entering into ESP setup mode by using button, it indicates as the picture below.

2

Select ESP fan step by pressing button. (01: very low, 02: low, 03: medium, 04: high, 05: very high)

3

Move to ESP value setting by pressing button. (It is 000 when delivering from the warehouse.)

4

Press button to setup ESP value.

(It is possible to setup ESP value from 1 to 255, and 1 is the smallest and 255 is the biggest.)

5

Function code, ESP code

ESP value

If pressing button long for 3 seconds, it enters into remote controller setter setup mode.

- If pressing once shortly, it enters into user setup mode. Please press more than 3 seconds for sure.

1

Function Code ESP value

ESP step

Function code, ESP code

ESP value

Press button to save.

7

Select ESP fan step again by using button and setup ESP value, as No. 4 and 5, that corresponds each wind flow

6

Press button to exit. ❈ After setup, it automatically gets out of setup mode if there is no button

input for 25 seconds.

❈ When exiting without pressing set button, the manipulated value is not

reflected.

8

• If you set ESP incorrectly, the air conditioner may malfunction.

• This setting must be carried out by a certificated-technician.

This is the function that decides the strength of the wind for each wind level and because this function is to make the installation easier.

•

When setting ESP value on the product without very weak wind or power wind function, it may not work.

• Please be careful not to change the ESP value for each fan step.

• It does not work to setup ESP value for very low/power step for some products.

• ESP value is available for specific range belongs to the product.

Part 2 Functions & Controls

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LGE Internal Use Only

5.1 Hot start

• When heating is started, the indoor fan is stopped or very slow to prevent the cold air carry out

• When the temp. of heat exchanger reach 30°C(model by model), indoor fan is started.

5.2 Self-diagnosis Function

• The air conditioner installed can self-diagnosed its error status and then transmits the result to the central control. Therefore, a rapid countermeasure against failure of the air conditioner allows easy management and increases the usage life of air conditioner.

• Refer to trouble shooting guide.

5.3 Soft dry operation

• When the dehumidification operation input by the remote control is received, the intake air temperature is detected and the setting temp is automatically set according to the intake air temperature.

• While compressor off, the indoor fan repeats low airflow speed and stop.

• While the intake air temp is between compressor on temp. and compressor off temp., 10-min dehumidification operation and 4-min compressor off repeat.

Compressor ON Temp. ‘ Setting Temp+0.5°C Compressor OFF Temp. ‘ Setting Temp-0.5°C

• In 10-min dehumidification operation, the indoor fan operates with the low airflow speed.

5. Reliability

Intake air Temp. Setting Temp.

26°C ≤ intake air temp. 25°C

24°C ≤ intake air temp.< 26°C intake air temp. -1°C 22°C ≤ intake air temp. < 24°C intake air temp. -0.5°C 18°C ≤ intake air temp. < 22°C intake air temp.

intake air temp. < 18°C 18°C

Part 2 Functions & Controls

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LGE Internal Use Only

6.1 Cooling & heating Operations

6.1.1 Cooling Mode

• Operating frequency of compressor depends on the load condition, like the difference between the room temp. and the set temp., frequency restrictions.

• If the compressor operates at some frequency, the operating frequency of compressor cannot be changed within 30 seconds. ( not emergency conditions)

• Compressor turned off when

- intake air temperature is in between ±0.5°C of the setting temp. limit for three minutes continuously.

- intake air temperature reaches below 1.0°C of the temperature of setting temp..

• Compressors three minutes time delay.

- After compressor off, the compressor can restart minimum 3 minutes later.

6. Convenience Functions & Controls

6.1.2 Heating Mode

• Operating frequency of compressor depend on the load condition, The difference between the room temp. and set temp., frequency restrictions.

• If compressor operates at some frequency, the operating frequency of compressor cannot be changed within 30 seconds.

• Condition of compressor turned off

- When intake air temperature reaches +4°C above the setting temperature.

• Condition of compressor turned on

- When intake air temperature reaches +2°C above the setting temperature.

* Condition of indoor fan turned off

- While in compressor on : indoor pipe temp. < 20°C

- While in compressor off : indoor pipe temp. < 30°C

• While in defrost control, between the indoor and outdoor fans are turned off.

• Compressor 2minutes delay

- After compressor off, the compressor can restart minimum 2 minutes later.

CST/Duct/CVT type indoor unit matched with

Universal Outdoor unit

CST/ Duct/CVT type indoor unit

matched with Single Outdoor unit/Multi

Outdoor unit/Multi V Outdoor unit

Thermo ON : +2 °C above setting temp. Thermo OFF : +4 °C above setting temp.

Thermo ON : Setting temp. Thermo OFF : +3 °C above setting temp.

NOTE: Some Models are different by temperature of thermo ON/OFF.

Part 2 Functions & Controls

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LGE Internal Use Only

6.4 Auto restart Operation

• Whenever there is electricity failure to the unit, and after resumption of the power, unit will start in the same mode prior to the power failure. Memorized condition are on / off condition, operating mode (cooling/ heating), set temperature and fan speed. The unit will memorize the above conditions and start with same memorized condition.

6.2 Auto cleaning operation

• Function used to perform Self Cleaning to prevent the Unit from Fungus and bad odor.

• Used after the Cooling Operation before turning the unit off, clean the Evaporator and keep it dry for the next operation.

• The function is easy to operate as it is accessed through the Remote controller.

Unit

Operation

ON

OFF

Comp.

Indoor

Fan

ON

OFF

ON

OFF

Setting step

OFFL Low

Setting step

(Cooling Only)

6.3 Auto changeover operation

• The air conditioner changes the operation mode automatically to keep indoor temperature.

• When room temperature vary over ±2°C with respect to setting temperature, air conditioner keeps the room temperature in ±2°C with respect to setting temperature by auto change mode.

+4°C +2°C

+0.5°C

SET Temp.

-0.5°C

-2°C

Cooling operation

Heating operation Cooling

operation

Switching point

Heating thermo off

Cooling thermo off

Switching point

Part 2 Functions & Controls

- 24 -

LGE Internal Use Only

6.5 Child Lock Function

It is the function to use preventing children or others from careless using.

During the operation, when pressing the

TEMP

FAN

SPEED

OPER MODE

1

button and button for approx. 3 seconds, the ‘Child Lock’ Function can be used.

-

At the time of initial setting of the ‘Child Lock’, the ‘CL’ Will be indicated approx. 3 seconds at the temperature Display section before resuming to the previous mode. After the setting of the ‘CL’, if another button is setup, the button can not be recognized as the ‘CL’ is indicated at the temperature display section for approx. 3 seconds.

If the ‘CL’ function is wanted to be used

2

under the operation standby state, press the button and Button for approx. 3 seconds under the standby mode state and the system will be the ‘CL’ state.

FAN

SPEED

FAN

SPEED

As for the releasing method, when pressing

3

the Button and button for approx. 3 seconds, the ‘CL’ function can be released.

Press button repeatedly until

1

the is flashing.

If moving to 'setup' icon area by using button,

2

'setup' icon blinks, and child lock function is setup if pressing button at that time.

When cancelling lock function, if moving to 'cancel' icon by pressing

3

button and then, pressing button, child lock function is cancelled.

Press button to exit.

4

❈ After setup, it automatically gets out of setup mode if there is no

button input for 25 seconds.

❈ When exiting without pressing set button, the manipulated value is

not reflected.

FAN

SPEED

Part 2 Functions & Controls

- 25 -

LGE Internal Use Only

6.6 Forced operation

• To operate the appliance by force in case when the remote control is lost, the forced operation selection switch is on the main unit of the appliance, and operate the appliance in the standard conditions.

• The operating condition is set according to the outdoor temp. and intake air temperature as follows.

• The unit select the last operation mode in 3 hours.

• Operating procedures when the remote control can't be used is as follows :

- The operation will be started if the ON/OFF button is pressed.

- If you want to stop operation, re-press the button.

Indoor temp.

over 24°C

21~24°C

below 21°C

Setting temp.

22°C

23°C

24°C

Setting speed of

indoor fan

High speed

Operating Mode

Cooling

Healthy Dehumidification

Heating

Part 2 Functions & Controls

- 26 -

LGE Internal Use Only

6.7 Group Control

1. When installing more than 2 units of air conditioner to one wired remote controller, please connect as the right figure.

• If it is not event communication indoor unit, set the unit as slave.

• Check for event communication through the product manual.

2. When installing more than 2 wired remote controllers to one air conditioner, please connect as the right picture.

• When installing more than 2 units of wired remote controller to one air

conditioner, set one wired remote controller as master and the others all as slaves, as shown in the right picture.

• You cannot control the group as shown in the right for some products.

•

Refer to the product manual for more detail.

When controlling multiple indoor units with event communication function with one remote controller, you must change the master/slave setting from the indoor unit.

- Indoor units, the master/slave configuration of the product after

completion of indoor unit power ʻOFFʼ and then ʻONʼ the power after 1 minutes elapsed sign up.

- For ceiling type cassette and duct product group, change the

switch setting of the indoor PCB.

- For wall-mount type and stand type product, change the master/slave setting with the wireless remote controller. (Refer to

wireless remote controller manual for detail)

h When installing 2 remote controllers to one indoor unit with event communication function, set the master/slave of the

remote controller. (Refer to remote controller master/slave selection) When controlling the group, some functions excluding basic operation setting, fan level Min/Mid/Max, remote controller lock setting and time setting may be limited.

<When simultaneously connecting

2 sets of wired remote controller>

• When controlling in groups, set the master/slaver of the remote controller. Refer to Installer setting section on how to set master/slave for more detail.

12345678 12345678

#3 switch OFF: Master

(Factory default setting)

#3 switch ON: Slave

GND

12V

Signal wire

TEMP

FAN

SPEED

OPER

MODE

GND

12V

Signal wire

GND

12V

B Y R B Y R

MASTER SLAVE

Signal wire

GND

12V

Signal wire

TEMP

FAN SPEED

OPER MODE

TEMP

FAN SPEED

OPER MODE

GND

12V

B Y R B Y R

MASTER SLAVE

Signal wire

GND

12V

Signal wire

Part 2 Functions & Controls

- 27 -

LGE Internal Use Only

6.8 Sleep Timer Operation

• When the sleep time is reached after <1,2,3,4,5,6,7,0(cancel) hr> is input by the remote control while in appliance operation, the operation of the appliance stops.

• While the appliance is on pause, the sleep timer mode cannot be input.

• While in cooling mode operation, 30 min later since the start of the sleep timer, the setting temperature increases by 1°C. After another 30 min elapse, it increases by 1°C again.

• When the sleep timer mode is input while in cooling cycle mode, the airflow speed of the indoor fan is set to the low.

• When the sleep timer mode is input while in heating cycle mode, the airflow speed of the indoor fan is set to the medium.

6.9 Timer(On/Off)

6.9.1 On-Timer Operation

• When the set time is reached after the time is input by the remote control, the appliance starts to operate.

• The timer LED is on when the on-timer is input. It is off when the time set by the timer is reached.

• If the appliance is operating at the time set by the timer, the operation continues. While in Fuzzy operation, the airflow speed of the indoor fan is automatically selected according to the temperature.

6.9.2 Off-Timer Operation

• When the set time is reached after the time is input by the remote control, the appliance stops operating.

• The timer LED is on when the off-timer is input. It is off when the time set by the timer is reached.

• If the appliance is on pause at the time set by the timer, the pause continues.

Part 2 Functions & Controls

- 28 -

LGE Internal Use Only

6.10 Weekly Program

You can set the daily reservation in weekly unit. Weekly reservation keeps operating until before you cancel it once you setup

Please move to reservation setup mode by pressing reservation button.

1

❈ You can setup two weekly reservations for one day, and up to fourteen

reservations for a week. For example, to setup (Tuesday morning 11:30 turned on ~ afternoon 12:30 turned off), you setup in order below.

Please move to 'weekly' by

2

repeatedly pressing reservation button. 'Weekly' blinks at this time.

Please select weekly reservation or

3

weekly reservation ¡ by using button. ❈ You can setup two reservations,

weekly reservation 1 and weekly reservation 2, for a day.

Please move to 'date' setup part by

4

using button. If 'date' indication blinks, please setup date. You can setup date from Monday to Sunday.

Please move to 'AM/PM' setup part

5

of turning on by using button.

Please move to 'hour' setup part of

6

turning on by using button.

- It is the part to setup the time at which air-conditioner is turned on.

Please change time by using button.

7

- You can setup hour 0~12.

Please move to 'minute' setup part of turning on by using button.

8

If 'minute' indication blinks, please setup 'minute' by using button

9

Part 2 Functions & Controls

- 29 -

LGE Internal Use Only

h Indoor unit is turned on to desired temperature if it is configured using up/down button during preset of weekly operation time.

(Temperature selection range : 18℃~30℃)

- When desired temperature is not set, it is turned on automatically with desired temperature of previous operation.

Please move to 'AM/PM' setup part

10

11

of turning off by using button.

- AM/PM setup is identical with turning on time setup.

Please move to 'hour' setup part of turning off by using Right button.

- It is the part to reserve the time

at which air-conditioner is turned off.

- If 'hour' indication blinks, please

setup 'hour'.

Please setup 'hour' and 'minute'

❈

identically with the method to setup turning on time.

If finishing weekly reservation setup, please press setup/cancellation button.

12

13

Weekly reservation explanation

Reservation number

Weekly reservation setup for the day that you set is finished.

If you setup with the method identical with above by selecting the day that you'd like to setup, it operates weekly reservation. If you setup both turning on reservation time and turning off reservation time identically, it doesn't operate reservation drive.

Turning on time

Turning off time

Under bar: the indication that there is weekly reservation for corresponding day

Part 2 Functions & Controls

- 30 -

LGE Internal Use Only

6.11 Two Thermistor Control

h The function of 2TH has different operation characteristics according to the product.

This is the function to select the temperature sensor to judge the room temperature.

Temperature sensor selection Function

01 Remote controller Operation in remote controller temperature sensor

02 Indoor unit Operation in indoor unit temperature sensor

03 2TH

Cooling

Operation of higher temperature by comparing indoor unit's and wired remote controllerʼs temperature. (There are products that operate at a lower temperature.)

Heating

Operation of lower temperature by comparing indoor unit's and wired remote controller's temperature.

When pressing the button and

1

button simultaneously for more than 3 seconds, the system will be entered into the installer setting mode.

- After entering into the installer setting mode, select the thermistor sensor setting code value by pressing the button.

* Thermistor sensor selection code

value : 04

Select the desired setting value with the

2

FAN

SPEED

TEMP

OPER MODE

temperature up(▲), down(▼) button.

*Setting value 01: Remote

controller

Code value

02: Indoor unit 03: 2TH

OPER MODE

Val ue

When pressing the button, currently

3

established thermistor sensor location will be set up.

OPER

When pressing the button and

4

button simultaneously for more than 3 seconds after the setting has been completed, the setting mode will be released.

- If there isn’t any button input for more

than 25 seconds, the installer setting mode will also be released.

MODE

Part 2 Functions & Controls

- 31 -

LGE Internal Use Only

h The function of 2TH has different operation characteristics according to the product.

This is the function to select the temperature sensor to judge the room temperature.

Temperature sensor selection Function

01 Remote controller Operation in remote controller temperature sensor

02 Indoor unit Operation in indoor unit temperature sensor

03 2TH

Cooling

Operation of higher temperature by comparing indoor unit's and wired remote controllerʼs temperature. (There are products that operate at a lower temperature.)

Heating

Operation of lower temperature by comparing indoor unit's and wired remote controller's temperature.

If pressing button long for 3 seconds, it enters into

1

remote controller setter setup mode.

- If pressing once shortly, it enters into user setup mode. Please press more than 3 seconds for sure.

If moving to room temperature perception sensor selection menu by

2

pressing button, it indicates as picture below.

Set Thermistor value by pressing button. (01: Remote Controller,

3

02: Indoor, 03: 2TH)

Function Code Thermistor setting

Press button to save.

4

Pressing button will exit settings mode.

5

❈ After setup, it automatically gets out of setup mode if there is no button input

for 25 seconds.

❈ When exiting without pressing set button, the manipulated value is not

reflected.

Part 2 Functions & Controls

- 32 -

LGE Internal Use Only

7.1 Low Ambient control

• This Function is for cooling operating in outdoor low temperature .

• If outdoor temperature drops below certain temperature, liquid back is prevented by reducing outdoor fan speed.

• It can prevent frosting of evaporator and keep cooling operation

7. Special Function

7.2 Space control

Vanes angle can be controlled by pair, considering its installation environment.

• For example direct drafts can be annoying, leading to discomfort and reduced productivity vane control helps to eliminate this problem.

• Easily controlled by wired remote control.

• Air Flow can be controlled easily regarding any space environment.

7.3 Auto Elevation Grille

• Auto Elevation Grille is automatically down to height of max. 3.1 m. So it enables to install the Indoor unit at high ceiling space. And Auto Elevation Grille makes you cleaning the filter easily.

Outdoor pipe

T2°C

T1°C

Outdoor

Fan Speed

Setting Speed Off Off

Setting

Speed

Setting

Speed

Part 2 Functions & Controls

- 33 -

LGE Internal Use Only

n ELEVATION GRILL (REMOTE CONTROLLER_Accessory)

• How to Use Remote Controller

• Main Components of Lift Grill

As for operation of Remote Controller, use it by directing the transmitter part of Remote Controller to the receiver part of front panel directly under front panel.

• Do not drop it down or into water. Or else there is worry about trouble failure.

• Do not press hard the Remote Controller button with nail (ballpoint pen or other sharp substance). Or else there is worry about trouble failure.

• In case when obstacle such as curtain hides the signal reception part of receiver in between the space interval, Remote Controller operation is infeasible.

¿ Lift grill front panel assembly

¡ Bolts for installation (4 EA, P/No. 3A00255K)

¬ Instruction manual

√ Remote Controller for lift grill

Ascend

Signal transmitter" "

Descend

Stop

Part 2 Functions & Controls

- 34 -

LGE Internal Use Only

Autom

atic stop distance

S

If you want to change automatic distance setting,

consult with your sale agency.

Automatic Stop Distance of Grill

Ceiling height Low

Medium

High

(

Height: 3~4 m)

Automatic stop distance

1.5±0.5 m 2.5±0.5 m 3.5±0.5 m

- Depress the down button( ). Then suction grill descends and stops automatically at a certain distance.

- You may stop it at wanted distance point by depressing the stop button ( ) when descending.

- Depress the up button( ). Then suction grill goes up and enters into the front panel.

1. Stop the Air Conditioner Operation

2. Descend the Suction Grill

3. Raise the Suction Grill

- Depress the stop button( ). Make use of this when you want to stop it at your wished position.

4. Stop the Suction Grill during Rising

• Always stop the air conditioner operation for safety before operating lift grill.

• Take heed _ there is worry about dust fall etc. when suction grill descends.

• In case when the set automatic stop distance goes wrong, check the set value of operation panel and confirm if there is neither obstacle nor mankind.

• When you are not to remove obstacle, stop the operation before touching the obstacle.

• How to Operate the Lift Grill

Part 3 Basic Control

- 35 -

LGE Internal Use Only

Part 3 Basic Control

1. Normal operation..............................................................................................................36

2 Compressor control .........................................................................................................36

3. EEV( Electronic Expansion Valve) control ....................................................................36

Part 3 Basic Control

- 36 -

LGE Internal Use Only

Basic principle is to control the rpm of the motor by changing the working frequency of the compressor. Three phase voltage is supplied to the motor and the time for which the voltage will supplied is controlled by IPM (intelligent power module). Switching speed of IPM defines the variable frequency input to the motor.

1. Normal operation

Fuzzy control : Maintain evaporating temperature (Te) to be constant on cooling mode and constant condensing temper-

ature (Tc) on heating mode by fuzzy control to ensure the stable system performance.

2. Compressor control

Actuator Cooling operation Heating operation Stop state

Compressor Fuzzy control Fuzzy control Stop

Fan Fuzzy control Fuzzy control Stop

EEV

Super heating

fuzzy control

Discharge Temp. Control Min. Pulse

EEV operates with fuzzy control rules to keep The degree of superheat (2~3℃) or the target temperature of discharge pipe. ＊Cooling mode

The degree of superheat = Tsuction – Tevaporator Tsuction : temperature at suction pipe sensor(℃) Tevaporator : evaporation temperature (℃)

3. EEV( Electronic Expansion Valve) control

＊Heating mode the target temperature of discharge pipe = T condenser + α T condenser : condenser temperature (℃)

Linear control

System capacity

Cooling and heating load

Inverter linear control as cooling and heating load increasing

Part 4 Trouble Shooting

- 37 -

LGE Internal Use Only

Part 4 Trouble Shooting

1. Self-diagnosis Function.................................................................................................38

1.1 Error Indicator (Indoor)................................................................................................38

1.2 Error Indicator (Outdoor) .............................................................................................39

2. Pump Down.....................................................................................................................40

3. Evacuation ......................................................................................................................41

4. Gas Charging..................................................................................................................42

5. Cycle Part........................................................................................................................43

6. Electronic Parts ..............................................................................................................44

6.1 The Product doesn t operate at all..............................................................................44

6.2 The Product doesn't operate with the remote controller .............................................45

6.3 The Compressor/Outdoor Fan are don't operate ........................................................46

6.4 When indoor Fan does not operate.............................................................................47

6.5 When the louver does not operate..............................................................................48

6.6 Troubleshooting Indoor Error .....................................................................................49

6.7 Troubleshooting Outdoor Error ..................................................................................55

Part 4 Trouble Shooting

- 38 -

LGE Internal Use Only

1. Self-diagnosis Function

Ex) Error 03 (Remote controller error)

1.1 Error Indicator (Indoor)

* Because remote controller turn off when occur ERROR in simultaneous operation system, it should check LED blinks

of outdoor in order to confirm error code.

* Repeatedly after LED1 is turned on and off as the Error code number of tens digit, LED2 is turned on and off as the

Error code number of single-digit.

Error Code Description LED 1 (Green) LED 2 (Red) Indoor status

01 Indoor Room sensor error 0 1time ◑ OFF

02 Indoor in-pipe sensor error 0 2times ◑ OFF

03 Remote controller error 0 3times ◑ OFF

04 Drain pump error 0 4times ◑ OFF

05 Communication error indoor and outdoor 0 5times ◑ OFF

06 Indoor out-pipe sensor error 0 6times ◑ OFF

09 EEPROM error (indoor) 0 9times ◑ OFF

10 BLDC motor fan lock (indoor) 1time ◑ 0 OFF

Ceiling Cassette Type Display

10 degrees 1 degrees

The number of times to blink = Error code

3 Times 3 Times 3 Times

LED02G

(GREEN)

2 Sec.

LED1

LED2

Part 4 Trouble Shooting

- 39 -

LGE Internal Use Only

1.2 Error Indicator (Outdoor)

◑ :

A light on the display panel is blink.

If abnormal voltage is supplied, the protection circuits will turn off the product in order to prevent the component damage. The product will automatically restart after 3 minutes.

Outdoor Error Ex) Error 21 (DC Peack)

AUUW18GD2[LUU187HV] AUUW24GD2[LUU247HV]

AUUW36GD2[LUU367HV] AUUW42GD2[LUU427HV]

2times ◑ 1time ◑ OFF 2times ◑ 2times ◑ OFF 2times ◑ 3times ◑ OFF 2times ◑ 4times ◑ OFF 2times ◑ 6times ◑ OFF 2times ◑ 7times ◑ OFF 2times ◑ 9times ◑ OFF 3times ◑ 2times ◑ OFF 4times ◑ 0 OFF 4times ◑ 1time ◑ OFF 4times ◑ 3times ◑ OFF 4times ◑ 4times ◑ OFF 4times ◑ 5times ◑ OFF 4times ◑ 6times ◑ OFF 4times ◑ 8time ◑ OFF 5times ◑ 1times ◑ OFF 5times ◑ 3times ◑ OFF 6times ◑ 0 OFF 6times ◑ 1times ◑ OFF 6times ◑ 2times ◑ OFF 6times ◑ 5times ◑ OFF 6times ◑ 7times ◑ OFF

21 DC Peak(IPM Fault) 22 Max. CT(CT2) 23 DC Link Low Volt. 24 Pressure switch/Heater Sink. 26 DC Comp Position Error 27 PFC Fault Error 29 Comp Over Current 32 D-Pipe High(Inv.) 40 CT Sensor(Open/Short) 41 Inv. D-Pipe Th Error(Open/Short) 43 High Pressure Sensor(Open/Short) 44 Outdoor air Th Error(Open/Short) 45 Cond. Middle Pipe Th Error(Open/Short) 46 Suction Pipe Th Error(Open/Short) 48 Cond. Out-Pipe Th Error(Open/Short) 51 Capacity over 53 Communication Error(Indoor ÷ Outdoor) 60 EEPROM Error(Outdoor) 61 Cond. Middle Pipe High 62 Heatsink Error(High) 65 Heatsink Th Error(Open/Short) 67 BLDC motor fan lock(Outdoor)

Error Code

Description

LED 1

(Red)

LED 2

(Green)

Indoor

status

1 Time 1 Time 1 Time

2 Times2 Times2 Times

1 Sec.

2 Sec. 2 Sec.

1 Sec. 1 Sec.

LED01G

(RED)

LED02G

(GREEN)

Part 4 Trouble Shooting

- 40 -

LGE Internal Use Only

2. Pump Down

Setting Procedure

1) Set the Dip Switch as follow after shutting the power source down.

2) Reset the power.

3) Red LED and Green LED of PCB lights during work. (The indoor unit is operated by force.)

4) If operation is done, Red LED will be turned off. If operation is not done normally, Red LED will blink.

5) Close the Liquid valve only after green LED turned off (7 minutes from the start of the machine). Then close the gas valve after Green LED on.

WARNING:

• When the green LED of PCB is on, compressor is going to be off because of low pressure.

• You should return the Dip Switch to operate normally after finishing the operation.

• Improper Pump down will lead to product turn off along with LED (green &red) off with in 20 minutes from the initial start.

6

AUUW18GD2

[LUU187HV]

AUUW24GD2

[LUU247HV]

AUUW36GD2

[LUU367HV]

AUUW42GD2

[LUU427HV]

Pump Down Dip S/W Setting

Power on

(Red LED On, Green LED Off)

Comp on

(Red LED On, Green LED On)

Pump Down Start

(Red LED On, Green LED Off)

Pump Down Complete

(Red LED Off, Green LED On)

Power off

(Red LED Off, Green LED On)

Liquid Valve Closed

Gas Valve Closed

Part 4 Trouble Shooting

- 41 -

LGE Internal Use Only

• Procedure

(1) Connect the vacuum pump to the center hose

of charge set center hose

(2) Evacuation for approximately one hour.

– Confirm that the gauge needle has moved

toward 0.8Torr.

(3) Close the valve (Lo side) on the charge set,

turn off the vacuum pump, and confirm that the gauge needle does not move (approximately 5 minutes after turning off the vacuum pump).

(4) Disconnect the charge hose from the vacuum

pump.

– Vacuum pump oil.

If the vacuum pump oil becomes dirty or depleted, replenish as needed.

WARNING

Use a vacuum pump or lnert (nitrogen) gas when doing leakage test or air purge. Do not compress air or Oxygen and do not use Flammable gases. Otherwise, it may cause fire or explosion.

- Otherwise, it may cause personal injury.

3. Evacuation (All amount of refrigerant leaked)

Indoor unit

Vacuum pump

OPEN

Lo

Liquid side

OPEN

Gas side

Vacuum Gage

3-Way valve

Outdoor unit

Open

Part 4 Trouble Shooting

- 42 -

LGE Internal Use Only

• Procedure

(1) Connect the charge hose to the charging

cylinder.

– Connect the charge hose which you dis-con-

nected from the vacuum pump to the valve at the bottom of the cylinder.

– If you are using a gas cylinder, also use a

scale and reverse the cylinder so that the system can be charged with liquid.

(2) Purge the air from the charge hose.

– Open the valve at the bottom of the cylinder

and press the check valve on the charge set to purge the air. (Be careful of the liquid refrigerant). The procedure is the same if using a gas cylinder.

(3) Open the valve (Lo side on the charge set and

charge the system with liquid refrigerant.

– If the system can not be charged with the spec-

ified amount of refrigerant, it can be charged with a little at a time (approximately 150g each time) while operating the air conditioner in the cooling cycle; however, one time is not sufficient, wait approximately 1 minute and then repeat the procedure (pumping down-pin).

(4) Immediately disconnect the charge hose from

the 3-way valveʼs service port.

–

Stopping partway will allow the gas to be discharged.

–

If the system has been charged with liquid refrigerant while operating the air conditioner turn off the air conditioner before disconnecting the hose.

(5)

Mount the valve stem nuts and the service port nut.

– Use torque wrench to tighten the service port

nut to a torque of 1.8 kg.m.

– Be sure to check for gas leakage.

WARNING

When installing or relocation the unit, make sure that no substance other than the specified refrigerant(R410A) enter the refrigerant circult.

- Any presence of foreign substance such as air can cause an abnormal pressure rise and may result in explosion or injury.

This is different from previous procedures. Because you are charging with liquid refrigerant from the gas side, absolutely do not attempt to charge with larger amounts of liquid refrigerant while operating the air conditioner.

4. Gas Charging (After Evacuation)

Charging cylinder

Indoor unit

Check valve

(1)

OPEN

Lo

Liquid side

Gas side

3-Way valve

Vacuum Gage

Open

Outdoor unit

Part 4 Trouble Shooting

- 43 -

LGE Internal Use Only

Trouble analysis

1. Check temperature difference between intake and discharge air, and check for the operating current too.

Case Symptom Supposed Caused

Temp. difference : approx. 0°C Current : less than 80% of rated current

Temp. difference : approx. 8°C Current : less than 80% of rated current

Temp. difference : less than 8°C Current : over the rated current

Temp. difference : over 8°C

All amount of refrigerant leaked out. Check refrigeration cycle.

Refrigerant leakage Clog of refrigeration cycle Defective Compressor.

Excessive amount of refrigerant

Normal

Case 1

Case 2

Case 3

Case 4

Temperature difference between intake and discharge air depends on room air humidity. When the room air humidity is relativery higher, temperature difference is smaller. When the room air humidity is relatively lower temperature difference is larger.

2. Check temperature and pressure of refrigeration cycle in cooling mode.

1. The suction pressure is usually 8.5~9.5kg/cm2G(Cooling) at normal condition.(R410A)

2. The temperature can be measured by attaching the thermometer to the low pressure tubing and wrap it with putty.

NOTICE

Suction pressure

(Compared with Cause of Trouble Description

the normal value)

Defective compressor Current is low. Defective 4-way reverse valve

Excessive amount of High pressure does not quickly

Normal refrigerant rise at the beginning of

operation.

Insufficient amount of Current is low.

Lower Higher refrigerant (Leakage)

Clogging

High

Higher

Temperature of

Discharge Air (Compared

with the normal valve)

5. Cycle Part

Part 4 Trouble Shooting

- 44 -

LGE Internal Use Only

6.1 The Product doesn’t operate at all

The operation check of the Indoor PCB Assembly

Procedure

1) The input voltage of power module.

2) The output voltage of power module.

4) IC04D(7805)

5) IC01A(KIA7036)

Specification

1) AC230V ± 30V : Check the rated voltage

2) 12V ± 3V

4) DC5V

5) The voltage of micom pin 19 : DC4.5V↑

Remedy

1) Check the power outlet.

2) Replace PCB Assembly

4) Replace PCB Assembly

5) Replace PCB Assembly

6. Electronic Parts

Turn off the main power and

wait for 10 seconds.

Turn on the main power again.

A "Beeping" sound is made

from the indoor unit

No

Check the voltage of power supply (AC220V/AC240V, 50Hz) and check for the following :

Yes

Primarily, the operating condition of Micom is O.K.

* Check, Remote controller & Receiver. * Check CN-DISP1, CN-DISP2 of indoor PCB

* The voltage of main power supply. * The voltage applied to the unit. * The connecting method of Indoor/Outdoor connecting cable (each color) * The PCB Assembly (Fuse, Noise Filter, Power Module, Bridge Diode, etc.)

Part 4 Trouble Shooting

- 45 -

LGE Internal Use Only

6.2 The Product doesn't operate with the remote controller

Turn on the main power

A "Beeping" sound is made

from the indoor unit

Yes

Is it possible to turn on the unit

by ON/OFF button on display?

Yes

Is the remote controller

working properly?

Yes

* Check the contact point of CN-DISP 1, 2 connector & Re connector. * Check display PCB Assembly

- Voltage between CN-DISP1 - should be DC +5V,

- If problem still persists, Replace display PCB

3 6

No

* Refer to 10.1

* Check the voltage of power (AC220V/AC240V, 50Hz).

* When the mark ( ) is displayed in LCD screen, replace battery.

Part 4 Trouble Shooting

- 46 -

LGE Internal Use Only

Turn on the main power.

When in air circulation mode, compressor/outdoor fan is stopped.

Turn off main power.

Check the electrical wiring diagram of Outdoor side. Check the open or short of connecting wires between Indoor and Outdoor.

Check the sensor for Indoor temperature is attatched as close as to be effected by the themperature of Heat Exchange (EVA.)

When the sensor circuit for Indoor temperature and connector are in bad connection or are not engaged, Compressor/Outdoor fan is stopped.

• Check the related circuit of R02H(12.1K), R01H(1K), R04H(6.2K), R03H(1K), C01H(102),

C02H(102), Micom(pin No. ⑪, ⑫).

• Check the Indoor temperature sensor is disconnected or not (about 10K at 25°C).

Check the Relay(RY-PWR, RY-START) for driving Compressor.

• Check the voltage between brown and blue cable of terminal to connect the Outdoor (About AC220V / 240V).

• Check the related circuit of relay in Outdoor PCB Ass'y.

Operate Cooling Mode by setting the disired temperature of the remote controller is less than one of the Indoor temperature by 1°C at least.

6.3 The Compressor/Outdoor Fan are don't operate

Check Point

Between Micom(No. 19) and GND

DC 5V DC 0V

DC 12VDC 1V↓

Between IC01M(No. 10) and GND

Comp. ON Comp. OFF

Part 4 Trouble Shooting

- 47 -

LGE Internal Use Only

6.4 When indoor Fan does not operate.

Check the SSR high speed operation by remote control.

(the Indoor Fan Motor is connected)

Turn off main power.

Check the connection of CN-FAN.

Check the Fan Motor.

Check the Fuse(AC250V, T2A).

Turn on the main power

Check the related circuit of indoor Fan Motor.

• The pin No. 38of micom and the part for driving SSR.(Q01M)

• Check the related pattern.

• Check the SSR.

- SSR Open: Indoor Fan Motor never operate.

- SSR short: Indoor Fan Motor always operates in case of ON or OFF.

The voltage of Pin No 1(orange) and 3(black) of CN-FAN.

About AC 160V over About AC 50V over

SSR is not damaged Check SSR

Part 4 Trouble Shooting

- 48 -

LGE Internal Use Only

• Confirm that the vertical louver is normally geared with the shaft of Stepping Motor.

• If the regular torque is detected when rotating the vertical louver with hands ⇒ Normal

• Check the connecting condition of CN-U/D or CN0L/R Connector

• Check the soldering condition(on PCB) of CN-U/D or CN0L/R Connector

Check the operating circuit of the vertical louver

• Confirm that there is DC +12V between pin ¿ of CN-U/D, CN0L/R and GND.

• Confirm that there is a soldering short at following terminals.

- Between 1 , 2 , 3 and 4 of MICOM - Between 17, 18, 19and 20of MICOM

- Between 4 , 5 , 6 and 7 of IC01M - Between 5 , 6 , 7 and 8 of IC01M

6.5 When the louver does not operate.

If there are no problems after above checks.

• Confirm the assembly condition that are catching and interfering parts in the link of the vertical louver

Part 4 Trouble Shooting

- 49 -

LGE Internal Use Only

6.6 Troubleshooting Indoor Error

Check Point

1. Unplug the sensor on Indoor unit PCB.

2. Estimate the resistance of each sensor.

3. If the resistance of the sensor is 10KΩ/ 5KΩ at 25°C, then sensor is normal.

4. If the resistance of the sensor is 0 KΩ or ∞, then sensor is abnormal. ’ Change the sensor.

5. Plug the sensor on Indoor unit PCB and Power ON.

6. Estimate the voltage of each sensor.

7. If the voltage of the sensor is 2.5Vdc at 25°C, then sensor is normal.

8. If the resistance of the sensor is 0 or 5Vdc, then sensor is abnormal. ’ Repair or Change the PCB.

01

02

06

Indoor air sensor

Indoor inlet pipe sensor

Indoor outlet pipe sensor

•

Connector connection error

• Faulty PCB

•

Faulty sensor (Open / Short)

•

Connector connection error

• Faulty PCB

•

Faulty sensor (Open / Short)

•

Connector connection error

• Faulty PCB

•

Faulty sensor (Open / Short)

Normal resistor : 10KΩ/ at 25˚C (Unplugged) Normal voltage : 2.5Vdc / at 25˚C(Plugged) Refer to sensor resistance table.

Normal resistor : 5KΩ/ at 25˚C(Unplugged) Normal voltage : 2.5Vdc / at 25˚C(Plugged) Refer to sensor resistance table.

Normal resistor : 5KΩ/ at 25˚C(Unplugged)

Normal voltage : 2.5Vdc / at 25˚C(Plugged) Refer to sensor resistance table.

Display

code

Title Cause of error Check point & Normal condition

Check Flow Chart

Unplug the sensor

on Indoor unit PCB

Estimate the Voltage

of each sensor.

Check the

Connector connection

Is it normal ?

Yes

Estimate the resistance

of each sensor.

Is the resistance of

the sensor 10 /

5k at 25˚C?

Yes

Plug the sensor

on Indoor unit PCB

No Correct connection

Is the voltage of

the sensor 2.5Vdc

at 25˚C

Yes

Repair or Change the PCB.

No Correct connection

Unplugged Plugged

10k

Check the resistance

Check the voltage

2.5Vdc

V

Part 4 Trouble Shooting

- 50 -

LGE Internal Use Only

03

Communication Error

(Wired remote controller)

• Connector connection error

• Faulty PCB / Remote

controller

• Connection wire break

• Connection of wire

• Main PCB Volt. DC12V

• Noise interference

Display

code

Title Cause of error Check point & Normal condition

Check Point

1. Check the wire connection. (Open / Short) ’ Repair the connection

2. Check the soldering state of connector. (Soldered poorly) ’ Repair or Change the PCB.

3. Check the volt. Of main PCB power source. (DC 12V) ’ Repair or Change the main PCB.

4. Check the installation of wired remote controller. (Noise interference) ’ Adjust the state of installation

Check Flow Chart

Check the wire

connection(Open /

Short / Miswirring)

Is it normal ?

Is the soldering state

of connector is normal?

Check the volt. of main

PCB power source.

(DC 12V,DC 5V)

Yes

No Correct connection Or change connection wire

No Re-soldering component Or change the PCB

CN-REMO

Wired R/C

S

12V

(RD)

(YL)

GND

(BK)

Indoor Unit

12V

(RD)S(YL)

GND

(BK)

Is it normal ?

Yes

Check the installation of

wired remote controller.

(Noise interference)

Is it normal ?

No Correct connection Or change the PCB

No Adjust the state of installation

12Vdc

Check the Volt.

12Vdc

V

Check the Volt.

V

Part 4 Trouble Shooting

- 51 -

LGE Internal Use Only

Check the wire

connection (Open,

Soldered poorly)

❊ Drain pump check

Check drain tube

installation

Is it normal ?

Check the level of

water (Float moves top

position)

Is it normal ?

Check the wire

connection (Open,

Soldered poorly)

Is the float

switch clean ?

Yes

No Check Drain Pump

Yes

No Correct connection Or re-soldering PCB

Is the resistance of

Drain Pump? Normal

( about 400 ) ?

Yes

No Change the Drain Pump

Is the drain

pump clean ?

Yes

No Clean drain pump

No Clean float switch

Is the resistance of f

loat switch normal

(short) ?

Yes

No Change the float switch

Is it normal ?

No Correct connection Or re-soldering PCB

Check Flow Chart

CN-D/Pump

CN-Float

04

Drain pump

/ Float switch

• Float switch open.

(Normal : short)

• Water over flow

• The connection of wire (Drain pump/ Float switch)

• Drain pump power input. (220V)

• Drain tube installation.

• Indoor unit installation. (Inclination)

Display

code

Title Cause of error Check point & Normal condition

Check Point

1. Check the wire connection. (Open / Short) ’ Repair the connection

2. Check the soldering state of connector. (Soldered poorly) ’ Repair or Change the PCB.

3. Check the volt. Of main PCB power source. (DC 12V) ’ Repair or Change the main PCB.

4. Check the installation of wired remote controller. (Noise interference) ’ Adjust the state of installation ※ To change drain pump assmbly for service, first separate c/box and disassemble drain pump assembly for

LHN240HV.

Part 4 Trouble Shooting

- 52 -

LGE Internal Use Only

09

EEPROM

Check sum (Indoor)

• Check sum error

• Check the poor soldering.

• Check the PCB Connection.

Display

code

Title Cause of error Check point & Normal condition

Check Flow Chart (CH09)

Check the the

connection port.

Is it normal ?

Yes

Change Option PCB

No Correct connection

Part 4 Trouble Shooting

- 53 -

LGE Internal Use Only

10

Indoor BLDC Fan Motor

Lock

The Fan is not operated properly

Check the Indoor fan locking

Display

code

Title Cause of error Check point & Normal condition

Check Point

Check the PCB during the Power on

1. Check the Voltage Red line to Black line

’ The Voltage is about [input voltage x 1.414] ’ if the Voltage does not come with the above Voltage, ’ Check the power input ’ Replace the PCB & Motor

2. Check the Voltage Black line to White

’ the Voltage is DC 15V ’ Check the Power input ’ Replace the motor

Check the Motor

1. Check the shaft

’ if the shaft is not turn smoothly, the Motor Power IC is defected ’ replace the motor

2. Check the motor resistance(if the shaft is turn smoothly, check the resistance)

’ Check Red line to Black line, Blue line to Black line ’ The resistance should infinite ’ replace the motor

Yellow

White

Blue

Black

Red

Fan motor connector

Tester

Part 4 Trouble Shooting

- 54 -

LGE Internal Use Only

05

/

53

Communication

(Indoor÷Outdoor)

• The connector for trans-

mission is disconnected.

• The connecting wires

are misconnected.

• The communication line

is break

• Outdoor PCB is

abnormal.

• Indoor PCB is abnormal.

• Synchro # of IDU is

abnormal.

• Check power input AC 230V. (Outdoor, Indoor)

• Check connector for transmission

• Check wires are misconnecting.

• Check transmission circuit of outdoor PCB

• Check transmission circuit of indoor PCB

• Check # of IDU setting DIP SW

Display

code

Title Cause of error Check point & Normal condition

Check Flow Chart

Check the input power

AC230V (Outdoor,

Indoor unit)

Is it normal ? (230V±10%)

Check the communication

wires are correctly

connected.

Is the connection of

Yes

No Needs electric work

GND,GND1,GND2,

correctly connected?

Yes

Change PCB

No Correct connection

Is it normal ?

Yes

Check the resistance

between communication

line and GND.

(Normal : Over 2M)

Is it normal ?

Yes

Is connector for communication

correctly connected?

No Adjust the connection of wire Confirm the wire of "Live", "Neutral", "Signal"

No Correct connection

1(L1)

2(L2)

❊ CH05 is displayed at indoor unit,

CH53 is displayed at outdoor unit.

1(L1)

2(L2)

Part 4 Trouble Shooting

- 55 -

LGE Internal Use Only

6.7 Troubleshooting Outdoor Error

21

DC PEAK

(IPM Fault)

• Instant over current

• Over Rated current

• Poor insulation of IPM

• An instant over current in the U,V,W phase

- Comp lock

- The abnormal connection of U,V,W

• Over load condition

- Overcharging of refrigerant Pipe length. Outdoor Fan is stop

• Poor insulation of compressor

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

n Comp checking method

Comp

Copper pipe

V

U

W

Comp

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

Model Resistance(Ω)

AUUW24GD2

[LUU247HV]

U-V 0.628(at 25˚C)

V-W 0.628(at 25˚C)

W-U 0.628(at 25˚C)

AUUW36GD2

[LUU367HV]

AUUW42GD2

[LUU427HV]

U-V 0.367(at 25˚C)

V-W 0.367(at 25˚C)

W-U 0.367(at 25˚C)

Model

Resistance(Ω) at 20°C

Terminal Inverter comp.

AUUW24GD2

[LUU247HV]

U-GND 2MΩ

V-GND 2MΩ

W-GND 2MΩ

AUUW36GD2

[LUU367HV]

AUUW42GD2

[LUU427HV]

U-GND 2MΩ

V-GND 2MΩ

W-GND 2MΩ

1. Check Pipe clogging/distortion

2. Check Covering (Indoor/Outdoor Unit)

Is installation

condition normal?

Yes

Are the resistance

Between each phase and

insulation resistance of Inverter

compressor normal?

No

3. Check EEV connector assemble condition/normal operation

4. Check refrigerant pressure → Reassemble or manage if abnormality found

1. Check resistance between each terminal of compressor

2. Check insulation resistance between compressor terminal and pipe

→ Replace compressor if abnormality found

Yes

1. Check inverter PCB assembly U,V,W connector

Is compressor

Wire connection

condition normal?

Yes

Is inverter PCB assembly normal?

Yes

Recheck power and installation condition

No

connection condition

2. Check wire disconnection and wiring

3. Check compressor terminal connection condition (bad contact)

→ Reassemble if abnormality found

Check inverter PCB assembly IPM normality

→ Replace inverter PCB assembly

Part 4 Trouble Shooting

- 56 -

LGE Internal Use Only

n AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

Y^ Y] Y\ Y[ YZ YY YX

w ~ } | u u u

zwtZ

LED02M

LED01M

U

V

W

1. Wait until inverter PCB DC voltage is discharged after main power off.

2. Pull out V, V, W COMP connector.

3. Set multi tester to resistance mode.

4.

If the value between P and N terminal of IPM is short(0Ω) or open(hundreds MΩ), PCB needs to be replaced.(IPM damaged)

5. Set the multi tester to diode mode.

6. In case measured value is different from the table, PCB needs to be replaced.(PCB damaged).

P W V U Nw Nv Nu P W V U Nw Nv Nu

27 26 25 24 23 22 21

0.4 ~ 0.6 V

27 26 25 24 23 22 21

0.4 ~ 0.6 V

PFC_IPM check U, V, W ‘ R S T

Part 4 Trouble Shooting

- 57 -

LGE Internal Use Only

n AUUW36GD2[LUU367HV] / AUUW42GD2[LUU427HV]

1. Wait until inverter PCB DC voltage is discharged after main power off.

2. Pull out AC(L), AC(N) connectors and U,V,W COMP Connector.

3. Set multi tester to resistance mode.

4.

If the value between P and N terminal of IPM is short(0Ω) or open(hundreds MΩ), PCB needs to be replaced.(IPM damaged)

5. Set the multi tester to diode mode.

6. In case measured value is different from the table, PCB needs to be replaced.(PCB damaged).

AC(N)-BLUE

AC(L)-BROWN

UVW

U,V,W CONNECTOR

P W V U Nw Nv Nu P W V U Nw Nv Nu

27 26 25 24 23 22 21

0.4 ~ 0.6 V

27 26 25 24 23 22 21

0.4 ~ 0.6 V

PFC_IPM check U, V, W ‘ R S T

Part 4 Trouble Shooting

- 58 -

LGE Internal Use Only

22

Max. C/T

• Input Over Current

• Malfunction of compressor

• Blocking of pipe

• Low voltage input

• Refrigerant, pipe length, blocked, …

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

1. Check Pipe clogging/distortion

Is installation

condition normal?

Yes

Are the resistance

Between each phase and

insulation resistance of Inverter

compressor normal?

No

2. Check Covering (Indoor/Outdoor Unit)

3. Check EEV connector assemble condition/normal operation

4. Check refrigerant pressure → Reassemble or manage if abnormality found

1. Check resistance between each terminal of compressor

2. Check insulation resistance between compressor terminal and pipe → Replace compressor if abnormality found

Yes

Is compressor

Wire connection

condition normal?

Yes

Is inverter PCB assembly power connection normal?

Yes

Is input voltage normal?

Yes

Is inverter PCB assembly

normal?

Yes

No

1. Check inverter PCB assembly U,V,W connector connection condition

2. Check wire disconnection and wiring

3. Check compressor terminal connection condition (bad contact) → Reassemble if abnormality found

Check connection between inverter PCB assembly and bridge diode(misconnection, disconnection) → wiring again if abnormality found

Check L~N phase is 230V 15% → Check connection condition and wiring if power is abnormal

Check inverter PCB assembly IPM normality → Replace inverter PCB assembly

Recheck power and installation condition

Part 4 Trouble Shooting

- 59 -

LGE Internal Use Only

Check Point

1. Check the power source.(230V ±15%)

2. Check the fan operation is right.

3. Check the current.

4. Check the install condition.

5. Check the CT Sensor Output signal (LUU247HV - Check output the CT Sensor : DC 2.5±0.2V) LUU367HV / LUU427HV - Check output pin 2.3 of the CT Sensor : DC 2.5±0.2V

1

2

3

Vdc

* AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

* AUUW36GD2[LUU367HV] / AUUW42GD2[LUU427HV]

IN/I

GND

Red

Black

Vdc

Part 4 Trouble Shooting

- 60 -

LGE Internal Use Only

23

DC Link High / Low Volt

• DC Link Voltage is above 420Vdc

• DC Link Voltage is below 140Vdc

• Check CN_(L), CN_(N) Connection

• Check Input Voltage

• Check PCB DC Link voltage sensor parts

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

No

Is input voltage normal ?

Yes

No Is Inverter PCB assembly Power connection normal?

Check L~N Voltage is 230V±15%

Check connection from terminal block to Inverter PCB assembly CN(L), CN(N)

Yes

Is Inverter PCB Normal?

Yes

Recheck power and installation

condition

No

Replace inverter PCB assembly

Part 4 Trouble Shooting

- 61 -

LGE Internal Use Only

Check Point

1. Check the WCN_P(L),P(N) Connection condition at the Main PCB.(Refer to outdoor wiring diagram)

2. Check the DC Link voltage at not operating(280V

↑

)

3. Check the DC Link voltage at Comp operating(340V

↑

)

4. Check DC Link Sensing Signal :2.4~2.8V (Refer the Picture)

IN/I

GND

Black

Red

Vdc

* AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

Part 4 Trouble Shooting

- 62 -

LGE Internal Use Only

AUUW36GD2[LUU367HV] / AUUW42GD2[LUU427HV]

Vdc

GND

P

Part 4 Trouble Shooting

- 63 -

LGE Internal Use Only

Check Point

1. Check the Input Voltage (L1- L2 ‘ 230V±10%)

2. Check Input Voltage Sensor output voltage (2.5Vdc±10%)

25

Input voltage

• Abnormal Input voltage (140Vac , 300Vac)

• Check the power source.

• Check the components.

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

Is input voltage normal ?

Yes

Is Inverter PCB Normal?

Yes

Recheck power and installation condition

No

Check L~N Voltage is 230V±15%

No

Replace inverter PCB assembly

< Input Power Source Check Point >

Part 4 Trouble Shooting

- 64 -

LGE Internal Use Only

AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

IN/I

GND

Red

AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

Black

Vdc

GND

Vdc

INPUT(V)

< Inverter PCB>

< Input Voltage Sensing Check Point >

Part 4 Trouble Shooting

- 65 -

LGE Internal Use Only

26

DC Compressor

Position

• Compressor Starting fail error

• Check the connection of comp wire “U,V,W”

• Malfunction of compressor

• Check the component of “IPM”, detection parts.

Display

code

Title Cause of error Check point & Normal condition

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

n Error Diagnosis and Countermeasure Flow Chart

1. Check Pipe clogging/distortion

2. Check Covering (Indoor/Outdoor Unit)

Is installation

condition normal?

Yes

Are the resistance

Between each phase and

insulation resistance of Inverter

compressor normal?

No

3. Check EEV connector assemble condition/normal operation

4. Check refrigerant pressure → Reassemble or manage if abnormality found

1. Check resistance between each terminal of compressor

2. Check insulation resistance between compressor terminal and pipe → Replace compressor if abnormality found

Yes

Is compressor

Wire connection

condition normal?

Yes

Is inverter PCB assembly normal?

Yes

Recheck power and installation condition

No

1. Check inverter PCB assembly U,V,W connector connection condition

2. Check wire disconnection and wiring

3. Check compressor terminal connection condition (bad contact) → Reassemble if abnormality found

Check inverter PCB assembly IPM normality → Replace inverter PCB assembly

* AUUW18GD2[LUU180HV] / AUUW24GD2[LUU247HV]

U, V, W

GND

Vdc

Part 4 Trouble Shooting

- 66 -

LGE Internal Use Only

AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

GND

V

U W

Part 4 Trouble Shooting

- 67 -

LGE Internal Use Only

27

AC Input Instant over

Current Error

Inverter PCB input current is over100A(peak) for 2us

1. Overload operation (Pipe clogging/Covering/EEV defect/Ref. overcharge)

2. Compressor damage (Insulation damage/Motor damage)

3. Input voltage abnormal (L,N)

4. Power line assemble condition abnormal

5. Inverter PCB assembly Damage (input current sensing part)

Display

code

Title Cause of error Check point & Normal condition

h PFCM Moudle checking method

① Set the multi tester to diode mode. ② Check short between input signal pin which are

placed below PFC Module

③ Replace PCB assembly if it is short between pins

except No.4,5 pins.

CAUTION

PFCM module No.4,5 pins are internal short state.

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

n Error Diagnosis and Countermeasure Flow Chart

1.Check Pipe clogging/distortion

Is installation

condition normal?

Yes

No

2.Check Covering (Indoor/Outdoor Unit)

3.Check EEV connector assemble condition/normal operation

4.Check refrigerant pressure → Reassemble or manage if abnormality found

Is input voltage normal?

Yes

Is AC input Wire connection

condition normal?

Yes

Is compressor

Wire connection

condition normal?

Yes

Is inverter PCB assembly

normal?

Yes

Recheck power and

installation condition

No

Check L~N phase voltage is 230V ± 15% → Check connection condition and wiring if power is abnormal

1.Check L,N connection condition

2.Check wire disconnection and wiring → Reassemble if abnormality found

1.Check inverter PCB assembly U,V,W connector connection condition

2.Check wire disconnection and wiring

3.Check compressor terminal connection condition(bad contact) → Reassemble if abnormality found

Check inverter PCB assembly PFCM normality → Replace inverter PCB assembly

Part 4 Trouble Shooting

- 68 -

LGE Internal Use Only

* AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

* AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

Part 4 Trouble Shooting

- 69 -

LGE Internal Use Only

29

Inverter compressor over

current

Inverter compressor input current is over 30A

1. Overload operation (Pipe clogging/Covering/EEV defect/Ref. overcharge)

2. Compressor damage(Insulation damage/Motor damage)

3. Input voltage low

4. ODU inverter PCB assembly damage

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

1. Check Pipe clogging/distortion

Is installation

condition normal?

Yes

Are the resistance

Between each phase and

insulation resistance of Inverter

compressor normal?

No

2. Check Covering (Indoor/Outdoor Unit)

3. Check EEV connector assemble condition/normal operation

4. Check refrigerant pressure

→ Reassemble or manage if abnormality found

1. Check resistance between each terminal of compressor (0.438~0.628±7%)

2. Check insulation resistance between compressor terminal and pipe (over 2M

→ Replace compressor if abnormality found

Ω)

Yes

Is compressor

Wire connection

condition normal?

Yes

Is input voltage normal?

Yes

Is inverter PCB assembly

normal?

Yes

Recheck power and installation condition

No

1. Check inverter PCB assembly U,V,W connector connection condition

2. Check wire disconnection and wiring

3. Check compressor terminal connection condition (bad contact)

→ Reassemble if abnormality found

Check L~N phase is 230V±15%

→ Check connection condition and wiring if power is

abnormal

Check inverter PCB assembly IPM normality

→ Replace inverter PCB assembly

Part 4 Trouble Shooting

- 70 -

LGE Internal Use Only

Display

code

Title Cause of error Check point & Normal condition

32

High temperature in Discharge pipe of the inverter compressor

• Overload operation (Outdoor fan constraint, screened, blocked)

• Refrigerant leakage (insufficient)

• Poor INV Comp Discharge sensor

• LEV connector displaced / poor LEV assembly

• Check outdoor fan constraint/ screened/ flow structure

• Check refrigerant leakage

• Check if the sensor is normal

• Check the status of EEV assembly

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

CN_TH3 (RED 4Pin Connector)

Part 4 Trouble Shooting

- 71 -

LGE Internal Use Only

Display

code

Title Cause of error Check point & Normal condition

35 Low Presser Error

Excessive decrease of low pressure

• Defective low pressure sensor

• Defective outdoor/indoor unit fan

• Refrigerant shortage/leakage

•

Deformation because of damage of refrigerant pipe

• Defective indoor / outdoor unit EEV

• Covering / clogging (outdoor unit covering during

the cooling mode / indoor unit filter clogging during heating mode)

• SVC valve clogging

• Defective outdoor unit PCB

• Defective indoor unit pipe sensor

n Error diagnosis and countermeasure flow chart

Is service valve

opened?

Yes

Are communication cable/

piping normal?

No

Open service valve

check communication/ piping correction.

Yes

Is amount of refrigerant

normal?

[refer refrigerant part]

Yes

Is strainer Ok?*

Yes

Are the value of manifold

gauge and pressure

sensor same?

(Is the low pressure value

actually low?)

Yes

Check indoor / outdoor unit LEV Check Indoor unit PCB Check indoor / outdoor unit installation conditions

No

Is there pipe crack or trace

of refrigerant leakage?

Yes

Weld / reconnect the cracked portion and recharge refrigerant

Replace the strainer

Replace the pressure sensor

No

Adjust the amount of refrigerant (Additive charge)

* If the temperature difference between inlet and outlet of strainer is so large that frost or ice formation can be seen or confirmed then clogging of strainer should be checked (Notice: it is not full ice forming of strainer, in case that there is not at inlet portion but at outlet portion)

Part 4 Trouble Shooting

- 72 -

LGE Internal Use Only

39

Transmission Error

Between (PFC Micom ’

INV Micom)

Communication Error Between PFC Micom and INV Micom.

1. Micom defect/Circuit defect

2. Different Micom S/W Version

3. ODU inverter PCB assembly damage

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

Is PFC Micom & INV Micom S/W Program normal?

Yes

Is Inverter PCB assembly normal?

Yes

No

Upgrade Micom Program

Replace inverter PCB assembly

Recheck power and installation condition

Part 4 Trouble Shooting

- 73 -

LGE Internal Use Only

Check Point

1. Check the Input Voltage (L1- L2 ‘ 230V±10%)

2. Check Input Voltage Sensor output voltage (2.5Vdc±10%)

n Error Diagnosis and Countermeasure Flow Chart

40

C/T

Sensor Error

• Initial current error

•

Malfunction of current detection circuit. (Open / Short)

•

Check CT Sensor output voltage :

2.5Vdc ±5%

Display

code

Title Cause of error Check point & Normal condition

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

n Error Diagnosis and Countermeasure Flow Chart

Is input voltage normal ?

Yes

Is Inverter PCB Normal?

No

Check L~N Voltage is 230V±15%

No

Replace inverter PCB assembly

Yes

Recheck power and

installation condition

< Input Power Source Check Point >

Part 4 Trouble Shooting

- 74 -

LGE Internal Use Only

AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

IN/I

GND

Black

Red

AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

Black

Vdc

1

2

3

Part 4 Trouble Shooting

- 75 -

LGE Internal Use Only

Display

code

Title Cause of error Check point & Normal condition

41 D-pipe sensor (Inverter)

• Open / Short

• Soldered poorly

• Internal circuit error

1. Bad connection of thermistor connector

2. Defect of thermistor connector (Open/Short)

3. Defect of outdoor PCB

44 Air sensor

• Open / Short

• Soldered poorly

• Internal circuit error

1. Bad connection of thermistor connector

2. Defect of thermistor connector (Open/Short)

3. Defect of outdoor PCB

45

Condenser Mid-pipesensor

• Open / Short

• Soldered poorly

• Internal circuit error

1. Bad connection of thermistor connector

2. Defect of thermistor connector (Open/Short)

3. Defect of outdoor PCB

46 Suction Pipe sensor

• Open / Short

• Soldered poorly

• Internal circuit error

1. Bad connection of thermistor connector

2. Defect of thermistor connector (Open/Short)

3. Defect of outdoor PCB

48

Condenser Out-pipe sensor

• Open / Short

• Soldered poorly

• Internal circuit error

1. Bad connection of thermistor connector

2. Defect of thermistor connector (Open/Short)

3. Defect of outdoor PCB

Ω"

Check Point

1. Estimate the resistance of each sensor.(Unplugged)

2. Check the value of the resistor of thermistor. D-pipe sensor (Inverter) : Normal Value of the resistor is 200kΩ at 25℃ Air sensor : Normal Value of the resistor is 10kΩ at 25℃ Cond. Mid-pipe sensor : Normal Value of the resistor is 5kΩ at 25℃ Suction pipe sensor : Normal Value of the resistor is 5kΩ at 25℃ Condenser Out-pipe sensor : Normal Value of the resistor is 5kΩ at 25℃

n Error Diagnosis and Countermeasure Flow Chart

Is sensor connected

to PCB correctly??

Yes

Is sensor value correct?*

Yes

Replace corresponding outdoor unit PCB

No

Connect sensor to PCB correctly

Replace sensor

Part 4 Trouble Shooting

- 76 -

LGE Internal Use Only

Display

code

Title Cause of error Check point & Normal condition

43

Sensor error of high pressure

Abnormal value of sensor (Open/Short)

• Bad connection of connector PCB

• Bad connection high pressure connector

• Defect of high pressure connector (Open/Short)

• Defect of connector PCB (Open/Short)

• Defect of outdoor main PCB.

Is sensor connected

to PCB correctly?

Connect sensor to PCB correctly

Replace corresponding pressure sensor

Yes

No

Replace the pressure sensor

Yes

No

Yes

END

After replacement of outdoor unit main PCB is the system

also abnormal?

Is pressure sensor OK?

(Check the value of

pressure sensor.

Cf. Output voltage is about

1.4V at 1500kPa)

Display

code

Title Cause of error Check point & Normal condition

51 Over capacity

• Over capacity Combination

• Check the indoor unit capacity.

• Check the combination table.

Part 4 Trouble Shooting

- 77 -

LGE Internal Use Only

53

Title

Communication

(Indoor ’ Outdoor)

• Communication poorly

• Power input AC 230V. (Outdoor, Indoor)

• The connector for transmission is disconnected.

• The connecting wires are misconnected.

• The communication line is shorted at GND.

• Transmission circuit of outdoor PCB is abnormal.

• Transmission circuit of indoor PCB is abnormal.

Display

code

Title Cause of error Check point & Normal condition

Check Point

1. Check the input power AC230V. (Outdoor, Indoor unit)

2. Check the communication wires are correctly connected. Adjust the connection of wire Confirm the wire of "Live", "Neutral"

3. Check the resistance between communication line and GND. (Normal : Over 2MΩ)

4. Check the connector for communication is correctly connected.

5. If one indoor unit is operated normally, outdoor PCB is no problem. Check the another indoor unit.

* CH05 is displayed at indoor unit, CH53 is displayed at

outdoor unit.

6. If all indoor unit is displayed CH05 but outdoor PCB not display

CH53 : Check the CN_COM and CN_POWER is correctly connected.

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

Part 4 Trouble Shooting

- 78 -

LGE Internal Use Only

60

Inverter PCB & Main

EEPROM check sum error

EEPROM Access error and Check SUM error

1. EEPROM contact defect/wrong insertion

2. Different EEPROM Version

3. ODU Inverter & Main PCB assembly damage

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

Check Point

- Check the EEPROM Check sum & Direction

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

1.Check EEPROM insert direction/connection condition

2.Check EEPROM Check SUM → Replace if abnormality found

Replace inverter PCB assembly

Is EEPROM insertion normal?

Yes

Is inverter PCB assembly normal?

No

Yes

MAIN PCB assembly normal?

Yes

Recheck power and installation condition

No

Replace MAIN PCB assembly

* AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

Part 4 Trouble Shooting

- 79 -

LGE Internal Use Only

* AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

EEPROM

Part 4 Trouble Shooting

- 80 -

LGE Internal Use Only

Display

code

Title Cause of error Check point & Normal condition

61

High temperature in outdoor Cond. Pipe

• Overload operation (Outdoor fan constraint, screened, blocked)

• Outdoor unit heat exchanger contaminated

• EEV connector displaced / poor EEV assembly

• Poor Cond. Pipe sensor assembly / burned

• Check outdoor fan constraint / screened / flow structure

• Check if refrigerant overcharged

• Check the status of EEV assembly

• Check the status of sensor assembly / burn

CN- C/PIPE (Violet 3Pin Connector)

Recheck power and installation condition

WARNING

Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.

Part 4 Trouble Shooting

- 81 -

LGE Internal Use Only

62

Heatsink High error

Inverter PCB heatsink temperature is over 85°C

1. ODU fan locking

2. Heatsink assembly of INV PCB assemble condition abnormal

3. Defect of temperature sensing circuit part defect of INV PCB

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

Is installation

condition normal ?

No

Yes

1. Check fan locking

2. Check covering of heat exchanger

3. Check distance between ODU and obstacles

4. Check pipe distortion and abnormality

5. Check service valve is opened → Eliminate causes for abnormal condition

Check resistance between NO.19 pin and NO.20 pin of PFC module → Replace PCB if abnormality found

Is assemble condition

of INV PCB heatsink normal ?

Is PCB temperature

sensing part normal ?

No

Yes

Check assemble condition between INV PCB heatsink and PFC & IPM module → Reassemble if abnormality found

Recheck installation condition

and connection of Heat sink

Yes

Check Point

1. Check resistance between No.19 pin and NO.20 pin of PCB PFC module

2. Resistance value should be in 7kΩ ±10%.(at 25°C).

Part 4 Trouble Shooting

- 82 -

LGE Internal Use Only

* AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

PFCM: Measuring resistance between No.19,20 pin

* AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

Ω

Part 4 Trouble Shooting

- 83 -

LGE Internal Use Only

65

Heatsink Sensor error

Inverter PCB heatsink sensor is open or short

1. ODU fan locking

2. Heatsink assembly of INV PCB assemble condition abnormal

3. Defect of temperature sensing circuit part defect of INV PCB

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

Check Point

1. Check resistance between No.19 pin and NO.20 pin of PCB PFC module

2. Resistance value should be in 7kΩ ±10%.(at 25°C).

3. Check the PFC Module No.19, 20 pin soldering condition.

1. Check fan locking

2. Check covering of heat exchanger

Is installation

condition normal ?

Yes

Is assemble condition

of INV PCB heatsink normal ?

Yes

No

3. Check distance between ODU and obstacles

4. Check pipe distortion and abnormality

5. Check service valve is opened → Eliminate causes for abnormal condition

Check assemble condition between INV PCB heatsink and PFC & IPM module → Reassemble if abnormality found

Is PCB temperature

sensing part normal ?

Yes

Recheck installation condition

and connection of Heat sink

No

Check resistance between NO.19 pin and NO.20 pin of PFC module → Replace PCB if abnormality found

Part 4 Trouble Shooting

- 84 -

LGE Internal Use Only

* AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

PFCM: Measuring resistance between No.19,20 pin

* AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

Ω

Part 4 Trouble Shooting

- 85 -

LGE Internal Use Only

67

Fan Lock Error

Fan RPM is 10RPM or less for 5 sec. when ODU fan starts or 40 RPM or less after fan starting.

1. ODU fan locking

2. Heatsink assembly of INV PCB assemble condition abnormal

3. Defect of temperature sensing circuit part defect of INV PCB

Display

code

Title Cause of error Check point & Normal condition

Is ODU Fan Motor Assemble

condition normal?

No

Yes

Recheck power and installation condition

Check ODU Fan Motor assemble condition and fan locking → Reassemble or replace if abnormality found

Is ODU Fan Motor normal?

No

Yes

1. Set the multi tester to diode mode.

2. Check voltage between 1pin and 4pin of Fan Motor (1Ţ0.2V)

3. Replace Inverter PCB if abnormality found.

Is wire connection of

ODU Fan Motor wire normal?

No

Yes

Check wiring between OUD fan motor and Inverter PCB ( Check if Hall Senor and Motor output terminal color is matched) →Reassemble if abnormality found

Is Inverter PCB assembly normal?

No

Yes

Replace Inverter PCB assembly

n Error Diagnosis and Countermeasure Flow Chart

Check Point

1. Check voltage between 1pin and 4pin of Fan Mortor connector (Tester diode mode)

2. Voltage value should be in 1V ±0.2V.

3. Do not replacing all of fan motor and PCB at once. Check error code again, after replacing the abnormal part (Fan Motor or PCB) first.

Part 4 Trouble Shooting

- 86 -

LGE Internal Use Only

AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

Check voltage betwen 1pin and 4pin of fan motor

Fan motor connector

Tester

Part 4 Trouble Shooting

- 87 -

LGE Internal Use Only

73

AC input instant over cur-

rent error

(Matter of software)

Inverter PCB input power current is over 48A(peak) for 2ms

1. Overload operation (Pipe clogging/Covering/EEV defect/Ref.overcharge)

2. Compressor damage (Insulation damage/Motor damage)

3. Input voltage abnormal (L, N)

4. Power line assemble condition abnormal

5. Inverter PCB assembly damage (input current sensing part)

Display

code

Title Cause of error Check point & Normal condition

n Error Diagnosis and Countermeasure Flow Chart

1.Check Pipe clogging/distortion

Is installation

condition normal?

Yes

Is input voltage normal?

Yes

No

2.Check Covering (Indoor/Outdoor Unit)

3.Check EEV connector assemble condition/normal operation

4.Check refrigerant pressure → Reassemble or manage if abnormality found

Check L~N phase voltage is 230V ± 15% → Check connection condition and wiring if power is abnormal

Is AC input Wire connection

condition normal?

Yes

Is compressor

Wire connection

condition normal?

Yes

Is inverter PCB assembly

normal?

Yes

Recheck power and

installation condition

No

1.Check L,N connection condition

2.Check wire disconnection and wiring → Reassemble if abnormality found

1.Check inverter PCB assembly U,V,W connector connection condition

2.Check wire disconnection and wiring

3.Check compressor terminal connection condition(bad contact) → Reassemble if abnormality found

Check inverter PCB assembly IPM normality → Replace inverter PCB assembly

Part 4 Trouble Shooting

- 88 -

LGE Internal Use Only

N

L

* AUUW18GD2[LUU187HV] / AUUW24GD2[LUU247HV]

L

N

< Noise Filter wiring Check Point >

< Input Power Source Check Point >

N

L

< Main PCB wiring Check Point >

Part 4 Trouble Shooting

- 89 -

LGE Internal Use Only

AUUW36GD2[LUU367HV]/ AUUW42GD2[LUU427HV]

N

L

N

LN

N

L

LN

< Input Power Source Check Point >

P/NO : MFL62542020

January, 2013

LG SVC Schematic

Specifications and Main Features

Frequently Asked Questions

User Manual