Service Manual

LG Heat Pump Mini Split Systems Cooling - L3L24D09090900

LG Heat Pump Mini Split Systems Cooling - L3L30D09121800

LG Heat Pump Mini Split Systems Cooling - L4L30W07090912

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lg-l4l30w07090912-service-manual

SERVICE MANUAL
AIR CONDITIONER
Please read this manual carefully before operating your set and retain it for future reference. General Multi-Inverter Type
P/NO : MFL68280204

Air Conditioner Service Manual
TABLE OF CONTENTS
Part 1 General Information ..........................................................................................................3 1. Safety Precautions........................................................................................................4 2. Model Line Up................................................................................................................7 3. Nomenclature ..............................................................................................................10
Part 2 Functions & Controls......................................................................................................14 1. List of Functions & Accessory ..................................................................................15 2. Air Flow .......................................................................................................................17 3. Air Purifying.................................................................................................................19 4. Installation Functions .................................................................................................20 5. Reliability .....................................................................................................................21 6. Convenience Functions & Controls .........................................................................22 7. Special Function & KIT ...............................................................................................29
Part 3 Basic Control ..................................................................................................................32 1. Normal operation ........................................................................................................33 2 Compressor control ....................................................................................................33 3. EEV( Electronic Expansion Valve) control ..............................................................33 4. Oil return control ........................................................................................................34 5. Defrost control ...........................................................................................................34 6. Protection control ......................................................................................................35
Part 4 Test Run ..........................................................................................................................36 1. Check before Test Run .............................................................................................37 2. Test Run Flow chart ..................................................................................................38 3. Test Runing.................................................................................................................39
Part 5 Trouble Shooting Guide ...............................................................................................41 1. Self-diagnosis Function .....................................................................................42 2. Pump Down .........................................................................................................44 3. Evacuation...........................................................................................................45 4. Gas Charging ......................................................................................................46 5. Cycle Part ............................................................................................................47 6. Electronic Parts...................................................................................................48

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LGE Internal Use Only

Part 1 General Information
Part 1 General Information
1. Safety Precautions ............................................................................................................4 2. Model Line Up .....................................................................................................................7 3. Nomenclature....................................................................................................................10

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LGE Internal Use Only

Part 1 General Information
1. Safety Precautions
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 provide grounding.
1.1 Cautions in Repair

Be sure to disconnect all remote electric power supplies before servicing. 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 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.
Be sure to provide the grounding when repairing the equipment in a humid or wet place, to avoid electrical shocks.

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LGE Internal Use Only

Part 1 General Information
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.
Do not turn on the breaker or power under condition that front panel, cabinet, top cover, control box cover are removed or opened. - Otherwise, it may cause fire, electric shock, explosion or death.
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.

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LGE Internal Use Only

1.2 Inspections after Repair

Part 1 General Information

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

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

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LGE Internal Use Only

Part 1 General Information
2. Model Line Up
2.1 Indoor units

Category

Functions

Reliability
Convenience Network function

Defrost/Deicing High pressure switch Low pressure switch Phase protection Restart delay (3-minutes) Self diagnosis Soft start Test function Night Silent Operation Wiring Error Check Peak Control Mode Lock Forced Cooling Operation (Outdoor Unit) Network soluation(LGAP)

[Note] : Applied, × : Not applied

Part 2 Functions & Controls
A2UW18GFH0[LMU180HHV] A3UW24GFH0[LMU240HHV] A4UW30GFH0[LMU300HHV] A5UW36GFH0[LMU360HHV] A6UW42GFH0[LMU420HHV]
O X X X O O O X O O O O O O

1.2 List of Accessory

Device

A2UW18GFH0[LMU180HHV] A3UW24GFH0[LMU240HHV] A4UW30GFH0[LMU300HHV]

A5UW36GFH0[LMU360HHV] A6UW42GFH0[LMU420HHV]

AC Ez (Simple Controller)

AC Ez Touch

Central Controller

AC Smart IV ACP IV

AC Manager IV

PI485

BNU (Building Network Unit)

LONWORKS Gateway BACnet Gateway

Y branch

Installation

Header branch

Air Guide

PDI (power distribution indicator)

ODU Dry Contact

Low Ambient Kit

PQCSZ250S0 PACEZA000 PACS4B000 PACP4B000 PACM4B000 PMNFP14A0/PMNFP14A1 PLNWKB000 PQNFB17C0
X X X PQNUD1S00 X O (Logical operation)

PQCSZ250S0 PACEZA000 PACS4B000 PACP4B000 PACM4B000 PMNFP14A0/PMNFP14A1 PLNWKB000 PQNFB17C0 PMBL5620
X X PQNUD1S00 X O (Logical operation)

[Note] O : Applied, × : Not applied Accessory model name : Installed at field, ordered and purchased separately by the corresponding model name, supplied with separate package.

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LGE Internal Use Only

Part 2 Functions & Controls
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.

Left

Right

110° ~ 120°

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.
Close

110° ~ 120°

Open

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.

CLOSED
Mode9 Mode8 Mode7 Mode6 Mode5
Mode4 Mode3 Mode2
OPEN

110~120° 7~8°

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

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LGE Internal Use Only

Part 2 Functions & Controls

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.

Step
LL L M H SH Auto

Discription
Very low, In heating mode Low Med High
Super high Chaos wind

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.

Vane 2

Vane 1

Vane 3

· Comparison of Air Flow Types 4-Open (conventional)

Swirl Swing (New)

Vane 4

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LGE Internal Use Only

Part 2 Functions & Controls

3. Air purifying

3.1 PLASMA Air Purifying System
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.

Dust particles

Dust electrode discharge

Ionizer

Photo-Catalyst Coated Mesh

+4.8KV discharge +

Polluted Air

+ +
+
+

Purified fresh Air

Odour

Odour molecule

Generating plasma

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LGE Internal Use Only

Part 2 Functions & Controls
4. Installation Functions
4.1 E.S.P. (External Static Pressure) Setting
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.

1 When pressing the

button and

OPER MODE

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 OPER button. MODE
* E.S.P code value : 03

TEMP

FAN SPEED

OPER MODE

2 Select the desired air flow rate with

the

FAN SPEED

button. Whenever pressing

the

FAN SPEED

button,

[SLoLoMedHiPo]

will

indicated.

3 Select the desired air flow rate value with the temperature up(), down() button. * E.S.P value range : 0~255 - E.S.P value will be indicated at the upper right section of the display window.

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

5 When pressing the

button and

OPER MODE

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.

· 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.

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LGE Internal Use Only

Part 2 Functions & Controls
5. Reliability
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.

Intake air Temp. 26°C intake air temp. 24°C intake air temp.< 26°C 22°C intake air temp. < 24°C 18°C intake air temp. < 22°C
intake air temp. < 18°C

Setting Temp. 25°C
intake air temp. -1°C intake air temp. -0.5°C
intake air temp. 18°C

· 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.

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LGE Internal Use Only

6. Convenience Functions & Controls

Part 2 Functions & Controls

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.

6.1.2 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.
NOTE: Some Models are different by temperature of thermo ON/OFF.

CST/Duct type indoor unit matched with Universal Outdoor unit
Thermo ON : +2 °C above setting temp. Thermo OFF : +4 °C above setting temp.

CST/ Duct/CVT type indoor unit matched with Single Outdoor unit/Multi
Outdoor unit/Multi V Outdoor unit
Thermo ON : Setting temp. Thermo OFF : +3 °C above setting temp.

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LGE Internal Use Only

Part 2 Functions & Controls
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 opera-
tion. · The function is easy to operate as it is accessed through the Remote controller.

Unit

Operation OFF

Indoor Fan
Comp.

ON
OFF Setting step
ON
OFF Setting step

(Cooling Only)

L Low

OFF

6.3 Auto Operation (Artificial Intelligence)

· When any of operation mode is not selected like the moment of the power on or when 3 hrs has passed since the operation off, the operation mode is selected.

· When determining the operation mode, the compressor, the outdoor fan, and the 4 way valve are off and only the in-

door fan is operated for 15 seconds. Then an operation mode is selected according to the intake air temp at that mo-

ment as follows.

24°C Inatake Air Temp

` Fuzzy Operation for Cooling

21°C Inatake Air Temp < 24°C ` Fuzzy Operation for Dehumidification

Inatake Air Temp < 21°C

` Fuzzy Operation for Heating

· If any of the operation modes among cooling / dehumidification / heating mode operations is carried out for 10 sec or longer before Fuzzy operation, the mode before Fuzzy operation is operated.

6.3.1 Fuzzy Operation for Cooling

· According to the setting temperature selected by Fuzzy rule, when the intake air temp is 0.5°C or more below the setting temp, the compressor is turned off. When 0.5°C or more above the setting temp, the compressor is turned on. Compressor ON Temp ` Setting Temp + 0.5°C Compressor OFF Temp ` Setting Temp + 0.5°C

· At the beginning of Fuzzy mode operation, the setting temperature is automatically selected according to the intake air

temp at that time.

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

· When the Fuzzy key (Temperature Control key) is input after the initial setting temperature is selected, the Fuzzy key value and the intake air temperature at that time are compared to select the setting temperature automatically according to the Fuzzy rule.

· While in Fuzzy operation, the airflow speed of the indoor fan is automatically selected according to the temperature.

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LGE Internal Use Only

Part 2 Functions & Controls

6.3.2 Fuzzy Operation for Dehumidification

· At the beginning of Fuzzy mode operation, the setting temperature is automatically selected according to the intake air

temp at that time.

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

· While in Fuzzy operation, the airflow speed of the indoor fan repeats the low airflow speed or pause as in dehumidification operation.

6.3.3 Fuzzy Operation for Heating
· According to the setting temperature selected by Fuzzy rule, when the intake air temp is 3°C or more above the setting temp, the compressor is turned off. When below the setting temp, the compressor is turned on. Compressor ON Temp ` Setting Temp Compressor OFF Temp ` Setting Temp + 3°C
· At the beginning of Fuzzy mode operation, the setting temperature is automatically selected according to the intake air temp at that time. 20°CIntake Air Temp ` Intake Air Temp + 0.5°C Intake Air Temp<20°C ` 20°C
· When the Fuzzy key (Temperature Control key) is input after the initial setting temperature is selected, the Fuzzy key value and the intake air temperature at that time are compared to select the setting temperature automatically according to the Fuzzy rule.
· While in Fuzzy operation, the airflow speed of the indoor fan is set to the high or the medium according to the intake air temperature and the setting temperature.
Notes: The Temp. of Comp. Turn ON and OFF is different in heating mode and fuzzy operation for heating. Please, refer 6.1

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.

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LGE Internal Use Only

Part 2 Functions & Controls
6.5 Child Lock Function
It is the function to use preventing children or others from careless using.

TEMP

FAN SPEED

OPER MODE

1 During the operation, when pressing the

button and

FAN SPEED

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.

2 If the `CL' function is wanted to be used under the operation standby state, press the

button and

FAN SPEED

Button for approx.

3 seconds under the standby mode state and the system will

be the `CL' state.

3 As for the releasing method, when pressing the Button and

FAN SPEED

button for approx. 3 seconds, the `CL' function can be

released.

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.

Indoor temp.

Operating Mode

Setting temp.

Setting speed of indoor fan

over 24°C

Cooling

22°C

21~24°C

Healthy Dehumidification

23°C

High speed

below 21°C

Heating

24°C

· 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.

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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.

Part 2 Functions & Controls

GND Signal wire
12V

GND Signal wire

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 `OFF' and then `ON' the
power after 1 minutes elapsed sign up. - For ceiling type cassette and duct product group, change the switch setting of the indoor PCB.

12345678
#3 switch OFF: Master (Factory default setting)

12345678 #3 switch ON: Slave

- 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.

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.

GND Signal wire
12V

B Y R

GND Signal wire
12V

MASTER

SLAVE

· 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.

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LGE Internal Use Only

Part 2 Functions & Controls
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.

6.10 Weekly Program
· If necessary, an operator can make an On/Off reservation of the product for a period of one week. - On/Off schedule of operation for a period of ONE week. · No need to turn the unit On/OFF manually during working days.
On/Off time is scheduled in micom of the wired remote control.

Operation Time Table (Example) Setting Mon Tue Wed Thu Fri

Sat Sun

Temp. 25°C 25°C 25°C 25°C 25°C

On 09:00 08:00 09:00 08:00 09:00

OFF

Off 12:00 17:00 12:00 12:00 12:00

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LGE Internal Use Only

6.11 Two Thermistor Control
This is the function to select the temperature sensor to judge the room temperature.

Part 2 Functions & Controls

1 When pressing the

button and

OPER MODE

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

OPER MODE

thermistor sensor setting code value by pressing the

button.

* Thermistor sensor selection code value : 04

TEMP

FAN SPEED
OPER MODE

2 Select the desired setting value with the temperature up(), down() button.

Code value

*Setting value 01: Remote
controller 02: Indoor unit 03: 2TH

Value

3 When pressing the button, currently established thermistor sensor location will be set up.

4 When pressing the

button and

OPER MODE

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.

Temperature sensor selection

Remote controller

Indoor unit

2TH

Cooling Heating

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

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

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LGE Internal Use Only

Part 2 Functions & Controls
7. Special Function & KIT
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

T2°C

Outdoor pipe

T1°C

Outdoor Fan Speed

Setting Speed

Off

Setting Speed

Off

Setting Speed

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.

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LGE Internal Use Only

Part 2 Functions & Controls
n ELEVATION GRILL (REMOTE CONTROLLER_Accessory)

Signal transmitter
Ascend Descend Stop

· Main Components of Lift Grill
¿ Lift grill front panel assembly ¡ Bolts for installation (4 EA, P/No. 3A00255K) ¬ Instruction manual Remote Controller for lift grill
· How to Use Remote Controller
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.

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LGE Internal Use Only

Part 2 Functions & Controls · How to Operate the Lift Grill

· 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 con-
firm if there is neither obstacle nor mankind. · When you are not to remove obstacle, stop the operation before touching the obstacle.

1. Stop the Air Conditioner Operation

Automatic Stop Distance of Grill

Automatic stop distance

2. Descend the Suction Grill
- 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.

3. Raise the Suction Grill
- Depress the up button( ). Then suction grill goes up and enters into the front panel.
4. Stop the Suction Grill during Rising
- Depress the stop button( ). Make use of this when you want to stop it at your wished position.

Ceiling height

Low

Medium (Height: 3~4 m)

High

Automatic stop distance 1.5±0.5m 2.5±0.5m 3.5±0.5m

S If you want to change automatic distance setting, consult with your sale agency.

7.4 Defrost Control (Heating)
· Defrost operation is controlled by timer and sensing temperature of outdoor pipe.
· The first defrost starts only when the outdoor pipe temperature falls below -11°C after starting of heating operation and more than 10 minutes operation of compressor.
· Defrost ends after 15 minutes passed from starting of defrost operation when the outdoor rises over 40°C even before 12 minutes.
· The second defrost starts only when the outdoor pipe temperature falls below 6°C after from ending of the first defrost and more than 10 minutes operation of compressor.

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LGE Internal Use Only

Part 3. Basic Control

1. Normal operation..............................................................................................................33 2 Compressor control .........................................................................................................33 3. EEV( Electronic Expansion Valve) control ....................................................................33 4. Oil return control .............................................................................................................34 5. Defrost control .................................................................................................................34 6. Protection control ............................................................................................................35
6.1 High pressure protection control ..........................................................................35 6.2 Low pressure protection control ..........................................................................35 6.3 Discharge temperature control ...........................................................................35 6.4 Input Current control ...........................................................................................35

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LGE Internal Use Only

Part 3. Basic Control

1. Normal operation

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.

Actuator Compressor
Fan
EEV

Cooling operation Fuzzy control Fuzzy control Super heating fuzzy control

Heating operation Fuzzy control Fuzzy control
Super heating & Sub cooling fuzzy control

Stop state Stop Stop
Min. Pulse

2. Compressor control
Fuzzy control : Maintain evaporating temperature (Te) to be constant on cooling mode and constant condensing temperature (Tc) on heating mode by fuzzy control to ensure the stable system performance.

Linear control

System capacity

Cooling and heating load Inverter linear control as cooling and heating load increasing
3. EEV( Electronic Expansion Valve) control
EEV operates with fuzzy control rules to keep the degree of superheat (about 2~3) at the evaporator outlet status. The degree of superheat = Tsuction Tevaporation Tsuction : temperature at suction pipe sensor() Tevaporation : evaporation temperature ()

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LGE Internal Use Only

4. Oil return control

Part 3. Basic Control

Oil return operation recovers oil amount in compressor by collecting oil accumulated in pipe. Each cycle component operates as shown on the below table during oil return operation.

Outdoor unit
Component Compressor
Fan EEV (Thermo on) EEV (Thermo off)
4 way valve

Starting Normal control Normal control Normal control
Min. Pulse On

Running Setting value
Off Setting value Setting value
Off

Ending Normal control Normal control Normal control
Min. Pulse On

Indoor unit
Component Fan
Defrost signal

Starting Normal control
Off

Running Off On

Ending Normal control
Off

5. Defrost control
Defrost operation eliminates ice accumulated on heat exchanger, recovering performance of heat exchanger. Each cycle component operates as shown on the below table during defrost operation.

Outdoor unit
Component Compressor
Fan EEV (Thermo on) EEV (Thermo off)
4 way valve

Starting Normal control Normal control Normal control
Min. Pulse On

Running Setting value
Off Setting value Setting value
Off

Ending Normal control Normal control Normal control
Min. Pulse On

Indoor unit
Component Fan
Oil return signal

Starting Normal control
Off

Running Off On

Ending Normal control
Off

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LGE Internal Use Only

Part 3. Basic Control
6. Protection control
6.1 High pressure protection control
Pressure range Pd 4069 kPa 3938 kPa Pd < 4069 kPa 3840 kPa Pd < 3938 kPa 3709 kPa Pd < 3840 kPa 3611 kPa Pd < 3709 kPa Pd < 3611 kPa
6.2 Low pressure protection control
n Cooling Mode Pressure range Pe > 310 kPa
278 kPa < Pe 310 kPa 245 kPa < Pe 278 kPa 212 kPa < Pe 245 kPa
Pe 212 kPa
n Heating mode Pressure range Pe > 294 kPa
255 kPa < Pe 294 kPa 229 kPa < Pe 255 kPa 203 kPa < Pe 229 kPa
Pe 203 kPa

Compressor Off
3Hz down 3Hz down Frequency holding 3 Hz up Normal control
Compressor Normal control
3Hz down 3Hz down 3Hz down
Off
Compressor Normal control
3Hz down 3Hz down 3Hz down
Off

6.3 Discharge temperature control
Temperature range Td 105
100 Td < 105 95 Td < 100 93 Td < 95 90 Td < 93
Td < 90

Compressor Off
5Hz down 5Hz down Frequency holding 3 Hz up Normal control

6.4 Input Current control

Input current

Normal control Less than 10A

Frequency down 14A or less

h Remarks: The data of pressure and frequency are different model by model.

Comp off Over than 14A

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LGE Internal Use Only

Part 4. Test Run

1. Check before Test Run.....................................................................................................37 2. Test Run Flow chart .........................................................................................................38 3. Test Running.....................................................................................................................39

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LGE Internal Use Only

Part 4. Test Run
1. Check before Test Run

Check to see whether there is any refrigerant leakage, and check whether the power or transmission cable is connected properly.

Check liquid pipe and gas pipe valves are fully opened.
2
NOTE: Be sure to tighten caps.

Confirm that 500 V megger shows 2.0 M or more between power supply terminal block and ground. Do not operate in the case of 2.0 M or less.

NOTE: Never carry out mega ohm check over terminal control board.

Otherwise the control board may break.

Immediately after mounting the unit or after leaving it turned off for an extended length of time, the resistance of the insulation between the power supply terminal board and the ground maydecrease to approx. 2.0 M as a result of refrigerant accumulation in the internal compressor.

If the insulation resistance is less than 2.0 M, turn on the main power supply.

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LGE Internal Use Only

2. Test Run Flow chart
START

Part 4. Test Run

Test operation for indoor unit

Operate the unit in cooling mode. No Does Test operation start?
Yes

Is cold air discharged for

more than 3 minutes ?

Yes

Is there any temperature

difference between intake and

discharged air?

Yes

Is the operating current

normal ?

Yes

Operation mode change to Heating mode

*Refer to Part 5.Trouble Shooting - 4. Gas Charging, 6.Electric Parts
*Refer to Part 5.Trouble Shooting - 4. Gas Charging, 5.Cycle Parts
* Check the load (In/Out Temp.) * Check pipe length and amount of
refrigerant * Check for abnormal sound in
outdoor unit (comp.,Fan, others )

Is hot air discharged ? After Hot Start Yes
Normal

No *Refer to Part 5.Troulbe Shooting

· Each indoor unit should be tested. · If the unit has accessory, it should be tested.
Copyright ©2017 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

Part 4. Test Run

3. Test Running

3.1 SPLIT, ART cool, ART cool deluxe Type

· Check that all tubing and wiring have been properly con-

Bolt

nected.

· Check that the gas and liquid side service valves are fully

open.

3.1.1 Prepare remote controller

Remove the battery cover by pulling it according to the arrow direction.
Insert new batteries making sure that the (+) and () of battery are installed correctly.
Reattach the cover by pushing it back into position.

Tubing connection
3.1.4 Evaluation of the performance

Operate unit for 15~20 minutes, then check the system refrigerant charge: 1. Measure the pressure of the gas side service valve. 2. Measure the temperature of the intake and discharge of air. 3. Ensure the difference between the intake temperature and the
discharge is more than 8°C (Cooling) or reversely (Heating).

NOTE: · Use 2 AAA(1.5volt) batteries. Do not use rechargeable
batteries. · Remove the batteries from the remote controller if the sys-
tem is not going to be used for a long time.
3.1.2 Precautions in test run
n The initial power supply must provide at least 90% of the rated voltage. Otherwise, the air conditioner should not be operated.
n For test run, carry out the cooling operation firstly even during heating season. If heating operation is carried out firstly, it leads to the trouble of compressor. Then attention must be paid.
n Carry out the test run more than 5 minutes without fail. (Test run will be cancelled 18 minutes later automatically)
n The forced operation is started by pressing button for 2 seconds. The test run is started by pressing button for 3~6 seconds.
n To cancel the test run, press any button.
3.1.3 Settlement of outdoor unit
n Anchor the outdoor unit with a bolt and nut(ø10mm) tightly and horizontally on a concrete or rigid mount.
n When installing on the wall, roof or rooftop, anchor the mounting base securely with a nail or wire assuming the influence of wind and earthquake.
n In the case when the vibration of the unit is conveyed to the hose, secure the unit with an anti-vibration rubber.

Discharge air
Discharge temperature

Chassis cover

Discharge air

Intake temperature

Discharge air

Discharge temperature
Intake temperature
Discharge temperature

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LGE Internal Use Only

3.2 Ceiling Cassette Type

Part 4. Test Run

3.2.1 PRECAUTIONS IN TEST RUN · The initial power supply must provide at least 90% of the rated voltage.
Otherwise, the air conditioner should not be operated.
CAUTION: For test run, carry out the cooling operation first even during winter season. If heating operation is carried out first, it leads to the trouble of compressor. Carry out the test run more than 5 minutes without stopping. (Test run will be cancelled 18 minutes later automatically)
· The test run is started by pressing the room temperature checking button and down timer button for 3 seconds at the same time.
· To cancel the test run, press any button.

3.2.2 CHECK THE FOLLOWING ITEMS WHEN INSTALLATION IS COMPLETE
· After completing work, be sure to measure and record trial run properties, and store measured data, etc. · Measuring data are room temperature, outside temperature, suction temperature, blow out temperature,
air velocity, air volume, voltage, current, presence of abnormal vibration and noise, operating pressure, piping temperature.
· As to the structure and appearance, check following items.

o Is the circulation of air adequate? o Is the drainage OK? o Is the heat insulation complete
(refrigerant and drain piping)? o Is there any leakage of refrigerant?

o Does the romote controller works properly? o Is there any error on wiring? o Aren't terminal screws loosened?
M4......118N.cm{12kgf.cm} M5......196N.cm{20kgf.cm} M6......245N.cm{25kgf.cm} M8......588N.cm{60kgf.cm}

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LGE Internal Use Only

Part 5. Trouble Shooting
Part 5. Trouble Shooting
1. Self-diagnosis Function.................................................................................................42 1.1 Error Indicator (Indoor)................................................................................................42 1.2 Error Indicator (Outdoor) .............................................................................................43
2. Pump Down.....................................................................................................................44
3. Evacuation ......................................................................................................................45
4. Gas Charging ..................................................................................................................46
5. Cycle Part........................................................................................................................47
6. Electronic Parts ..............................................................................................................48 6.1 The Product doesn t operate at all ..............................................................................48 6.2 The Product doesn't operate with the remote controller .............................................49 6.3 The Compressor/Outdoor Fan are don't operate ........................................................49 6.4 When indoor Fan does not operate.............................................................................51 6.5 When the louver does not operate. .............................................................................52 6.6 Troubleshooting Indoor Error ......................................................................................53 6.7 Troubleshooting Outdoor Error....................................................................................59

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LGE Internal Use Only

1. Self-diagnosis Function
1.1 Error Indicator (Indoor)
Ceiling Cassette Type Display

Part 5. Trouble Shooting

10 degrees 1 degrees The number of times to blink = Error code

Standard Libero Type Display

Libero-R

Libero-E

Cooling Heating Plasma

1 degrees 10 degrees

Cooling Heating Preheating

Artcool Mirror

1 degrees 10 degrees

Power Plasma Preheating

1 degrees 10 degrees

The number of times to blink = Error code

Error Indicator · The function is to self-diagnoisis airconditioner and express the troubles identifically if there is any trouble. · Error mark is ON/OFF for the operation LED of evaporator body in the same manner as the following table. · If more than two troubles occur simultaneously, primarily the highest trouble fo error code is expressed. · After error occurrence, if error is released, error LED is also released simultaneously. · To operate again on the occurrence of error code, be sure to turn off the power and then turn on. · Having or not of error code is different from Model.
Indoor Error

Error code

Description

No Error

Indoor Room themistor error

Indoor in-piping sensor error

Remote controller error

Drain Pump error

Communcation error between in and out

Indoor Out-Piping sensor error

Differnt mode operation

EEPROM Check Sum Error

Indoor BLDC Fan Lock

Indoor Status
ON OFF OFF OFF OFF OFF OFF OFF OFF OFF

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LGE Internal Use Only

Part 5. Trouble Shooting
1.2 Error Indicator (Outdoor)
Outdoor Error Ex) Error 21 (DC Peack)

LED01G (RED)
LED02G (GREEN)

2 Times
1 Sec. 1 Time
2 Sec.

2 Times

1 Sec. 1 Time

2 Sec.

Error Code
21 22
23
25 26 27 29 32 35
39
40 41 43 44 45 46 48 51 53
54
60 61 62 65 67 73

Contents
DC Link Peak (IPM Fault) CT 2 (Max CT) DC Link Low Volt. DC Link High Volt. Low Voltage/Over Voltage DC Compressor Position Error PSC/PFC Fault Error COMP Over Current D-Pipe High Low Pressure Error
Communication Error
CT Sensor (Open/Short) INV. D-Pipe Th Error High Pressure Sensor Error Outdoor Air Th Error Cond. Mid-Pipe Th Error Suction Pipe Th Error Cond. Out-Pipe Th Error Capacity Over Signal Error (Indoor <-> Outdoor)
3-Phase Wrong wiring
EEPROM Check Sum Error Cond. Pipe Th High Heaksink Th High Heaksink Th Error Outdoor BLDC Fan Lock PFC Fault Error(S/W)

LED01G/M LED02G/M (Red) (Green)

case of Error

2times 1times Over Rated Current

2times 2times Input Over Current

2times 3times DC Link Volt is below 140Vdc DC Link Volt is above 420Vdc

2times 5times Abnormal AC Volt Input

2times 6times Compressor Starting Fall Error

2times 7times Over Inverter PCB input current

2times 9times Over Inverter Compressor Current

3times 2times D-Pipe Temp. High

3times 5times Excessive decrease of Low Pressure

Outdoor Status
Off Off
Off
Off Off Off Off Off Off

3times

9times

Communication Error Between PFC Micom and INV Micom

Off

4times

CT Circuit Malfunction

Off

4times 1times Open/Short

Off

4times 3times Open/Short

Off

4times 4times Open/Short

Off

4times 5times Open/Short

Off

4times 6times Open/Short

Off

4times 8times Open/Short

Off

5times 1times Over combination

Off

5times 3times Communication Poorly

Off

5times

4times

3-Phase Wrong Wring of Outdoor Unit (Reverse Phase/Omission of Phase)

Off

6times

Check Sum Mismatching

Off

6times 1times Cond. Temp. High

Off

6times 2times Heatsink Temp. High

Off

6times 5times Open/Short

Off

6times 7times Outdoor Fan is not operation

Off

7times 3times Over Current of Outdoor Unit PFC

Off

: A light on the display panel is blink.

- 43 -

LGE Internal Use Only

2. Pump Down

Part 5. Trouble Shooting

This function gathers the refrigerant present in the system to ODU Use this function to store refrigerant of system in ODU for leakage or IDU replacement.

· Procedure

n This function start Dip switch setting status of ODU PCB. (1) Set the Dip switch as follow after shutting the power source down.

18,24,30kBtu/h class

36,42kBtu/h class

6
(2) Reset the power. (3) Check that the Red LED of PCB is on during work.(The indoor unit is operated by force.) (4) Pump down during forced cooling operation.
CAUTION
1. Use pump down function within guaranteed temperature range IDU : 20~32C ODU : 0~40C
2. Make certain that IDU doesn't run with thermo off mode during operation 3. After the compressor is starting operation, please complete Pump Down within 4 minutes. 4. Pump Down can be stopped (The compressor is turned off), because of compressor protection.
In this case, reset the power.

- 44 -

LGE Internal Use Only

Part 5. Trouble Shooting
3. Evacuation (All amount of refrigerant leaked)

Indoor unit

Liquid side

3-Way valve

Open

Outdoor unit

Gas side

3-Way valve

Open

Vacuum pump
OPEN

Vacuum

Gage

OPEN

· 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.

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LGE Internal Use Only

4. Gas Charging (After Evacuation)

Indoor unit

Liquid side
Open 3-Way valve

Part 5. Trouble Shooting
Outdoor unit

Charging cylinder

Check valve

Gas side
Open 3-Way valve

Lo (1) OPEN

Vacuum Gage

· Procedure
(1) Connect the charge hose to the charging cylinder. Connect the charge hose which you dis-connected 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 specified 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).

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) Immediately disconnect the charge hose from the 3-way valve's 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.

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LGE Internal Use Only

Part 5. Trouble Shooting

5. Cycle Part

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

Case Case 1

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

Supposed Caused
All amount of refrigerant leaked out. Check refrigeration cycle.

Case 2

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

Refrigerant leakage Clog of refrigeration cycle Defective Compressor.

Case 3 Case 4

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

Excessive amount of refrigerant Normal

NOTICE
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.

Suction pressure Temperature of Discharge

(Compared with Air (Compared with the

the normal value)

normal valve)

Cause of Trouble

Higher

High Normal

Defective compressor Defective 4-way reverse valve
Excessive amount of refrigerant

Lower

Higher

Insufficient amount of refrigerant (Leakage) Clogging

Description
Current is low.
High pressure does not quickly rise at the beginning of operation. Current is low.

NOTICE
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.

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LGE Internal Use Only

6. Electronic Parts
6.1 The Product doesn't operate at all
Turn off the main power and wait for 10 seconds.

Part 5. Trouble Shooting

Turn on the main power again.
A "Beeping" sound is made from the indoor unit No

Primarily, the operating condition of Micom is O.K. Yes
* Check, Remote controller & Receiver. * Check CN-DISP1, CN-DISP2 of
indoor PCB

Check the voltage of power supply (AC208/230V,60Hz) and check for the following :
* 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.)

The operation check of the Indoor PCB Assembly

Procedure
1) The input voltage of power module.

Specification
1) AC230V ± 30V : Check the rated voltage

2) The output voltage of power mod- 2) 12V ± 3V ule.

4) IC04D(7805) 5) IC01A(KIA7036)

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

- 48 -

LGE Internal Use Only

Part 5. Trouble Shooting
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

No * Refer to 6.1

* Check the voltage of power

(AC208/230V,60Hz).

Is the remote controller working properly?
Yes

* When the mark ( ) is displayed

in LCD screen, replace battery.

* Check the contact point of CN-DISP 1, 2 connector & Re connector. * Check display PCB Assembly - Voltage between CN-DISP1 3 - 6 should be DC +5V, - If problem still persists, Replace display PCB

6.3 The Compressor/Outdoor Fan are don't operate
Turn on the main power.

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.

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

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

- 49 -

LGE Internal Use Only

Part 5. Trouble Shooting

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

18,24,36kBtu/h class

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 AC208/230).
· Check the related circuit of relay in Outdoor PCB Ass'y.

Check Point
Between Micom(No. 19) and GND
Between IC01M(No. 10) and GND

Comp. ON DC 5V DC 1V

Comp. OFF DC 0V DC 12V

36,42kBtu/h class

Check the Relay(RY-PWR, RY-CHARGE) for driving Compressor.
· Check the voltage between brown and blue cable of terminal to connect the Outdoor (About AC208/230).
· Check the related circuit of relay in Outdoor PCB Ass'y.

Check Point

Comp. ON

Comp. OFF

Between Micom(No. 11) and GND
Between IC01M(No. 16) and GND

DC 5V DC 1V

DC 0V DC 12V

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

- 50 -

LGE Internal Use Only

Part 5. Trouble Shooting
6.4 When indoor Fan does not operate.
Turn off main power.
Check the connection of CN-FAN.
Check the Fan Motor.
Check the Fuse(AC250V, T2A).
Check the related circuit of indoor Fan Motor. · The pin No. 38 of 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.
Turn on the main power

Check the SSR high speed operation by remote control. (the Indoor Fan Motor is connected)
The voltage of Pin No 1(orange) and 3(black) of CN-FAN.

About AC 160V over SSR is not damaged

About AC 50V over Check SSR

- 51 -

LGE Internal Use Only

6.5 When the louver does not operate.

Part 5. Trouble Shooting

· 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 , 19 and 20 of MICOM - Between 4 , 5 , 6 and 7 of IC01M - Between 5 , 6 , 7 and 8 of IC01M

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

- 52 -

LGE Internal Use Only

Part 5. Trouble Shooting
6.6 Troubleshooting Indoor Error

Display code
01

Title Indoor air sensor

Cause of error
· Open / Short · Soldered poorly · Internal circuit error

· Open / Short 02 Indoor inlet pipe sensor · Soldered poorly
· Internal circuit error

· Open / Short
06 Indoor outlet pipe sensor · Soldered poorly · Internal circuit error

Check point & Normal condition
Normal resistor : 10K/ at 25°C (Unplugged) Normal voltage : DC 2.5V / at 25°C (plugged)
Normal resistor : 5K/ at 25°C (Unplugged) Normal voltage : DC 2.5V / at 25°C (plugged)
Normal resistor : 5K/ at 25°C (Unplugged) Normal voltage : DC 2.5V / at 25°C (plugged)

10k

2.5Vdc V

Check the resistance

Check the voltage

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 10K/ 5K at 25°C, then sensor is normal. 4. If the resistance of the sensor is 0 K 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.

- 53 -

LGE Internal Use Only

Display code
03

Title
Communication Wired R/C

Cause of error
· Open / Short · Wrong connection

Part 5. Trouble Shooting
Check point & Normal condition
· Connection of wire · Main PCB Volt. DC12V · Noise interference

Wired R/C 12V S GND

Indoor Unit 12V S GND

CN-REMO

12Vdc V

Check the Volt.

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

- 54 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Drain pump

/ Float switch

CN Float

Cause of error
· Float switch Open. (Normal : short)

Check point & Normal condition
· The connection of wire(Drain pump/ Float switch) · Drain pump power input. (230V) · Drain tube installation. · Indoor unit installation. (Inclination)

CN-Float
0

CN-D/PUMP

Check the resistance
Check Point
1. Check the wire connection. (Open, Soldered poorly) ' Repair the connection or change the PCB. 2. Check the resistance of float switch (Abnormal : Open, Normal : short) ' Check the float switch. 3. Check the level of water 4. Check the volt. Of Drain pump power supply. (AC 230V) ' Repair or Change the main PCB.

- 55 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Cause of error

Check point & Normal condition

· One of Indoor Unit oper-

07 Different Operation Mode ate cooling Another Unit · At the same time, this model cannot use cool and

operate heating

heating mode

Check Point
1. Check another indoor model operation mode
2. Operating the same mode with the first operated indoor unit
3. Clearing the "CH07" Press the on/off button or mode change button and matching the indoor unit mode same as the first operated indoor unit

- 56 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Cause of error

Indoor EEPROM Check Sum Error

· Check sum error

Check point & Normal condition
1. Check the poor soldering 2. Check the insertion condition of the EEPROM 3. Check the PCB Connection

<EEPROM Direction Check Point>
Check Point
1. Check the EEPROM Direction 2. If the EEPROM value & the Program value are not matched, the Code is Displayed 3. After Checking the connection and Insertion, replace the PCB or Option PCB

- 57 -

LGE Internal Use Only

Display code

Title

Cause of error

Part 5. Trouble Shooting
Check point & Normal condition

Indoor BLDC Fan Motor The Fan is not operated

Lock

properly

Check the Indoor fan locking

Yellow White Blue Black Red

Fan motor connector

Tester

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

- 58 -

LGE Internal Use Only

Part 5. Trouble Shooting

6.7 Troubleshooting Outdoor Error

Display code

Title

Cause of error

· Instant over current

DC PEAK

· Over Rated current

(IPM Fault)

· Poor insulation of IPM

Check point & Normal condition
· 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

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 installation

condition normal?

Yes

Are the resistance

Between each phase and

insulation resistance of Inverter

compressor normal?

Yes

Is compressor Wire connection

condition normal?

Yes

1. Check Pipe clogging/distortion 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
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

Is inverter PCB assembly normal?

Yes Recheck power and installation condition

n Comp checking method

Check inverter PCB assembly IPM normality Replace inverter PCB assembly

Comp U

Resistance() Model
Terminal Inverter Comp.

18,24,30 kBtu/h class

U-V V-W W-U

0.628(at 25°C) 0.628(at 25°C) 0.628(at 25°C)

36,42k Btu/h class

U-V V-W W-U

0.438(at 25°C) 0.438(at 25°C) 0.438(at 25°C)

Comp

Copper pipe

Resistance() at 20°C

Terminal

Inverter comp.

Constant comp.

U-GND V-GND W-GND

2M 2M 2M

- 59 -

LGE Internal Use Only

18,24,30kBtu/h class

IPM Check Point

Part 5. Trouble Shooting

27 25

33 32 30 29 27 26 25

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(0) or open(hundreds M), 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).

U V W Nu Nv Nw

27 26 25 24 23 22 21
0.4 ~ 0.6 V

U V W Nu Nv Nw

27 26 25 24 23 22 21

0.4 ~ 0.6 V

PFC_IPM check U, V, W ` R S T

- 60 -

LGE Internal Use Only

CN(N)_BLUE
Part 5. UT,rVo,WubClOeNSNhEoCToOtiRng 36,42kBtu/h class

CN(L)_BRWON

U V W

CN_INPUT_VOLT_N (BL) CN_INPUT_VOLT_L (BR)

1. Wait until inverter PCB DC voltage is discharged after main power off. 2. Pull out CN(L), CN(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(0) or open(hundreds M), 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).

IGBTM check U, V, W

0.3 ~ 0.5 V

Red

11-12 8-9

U 13-15

Black

25-26 P

- 61 -

Sequence of Measurement
1 2 3

Measurement
P-U P-V P-W

Normal Standards 0.3V~0.5V 0.3V~0.5V 0.3V~0.5V

LGE Internal Use Only

Display code
22

Title Max. C/T

Part 5. Trouble Shooting

Cause of error

Check point & Normal condition

Input over current (18,24,30kBtu/h class 19A 36,42kBtu/h class 37A )

1. Malfunction of Compressor 2. Blocking of Pipe 3. Low Voltage Input 4. Refrigerant, Pipe length, Blocked...

n Error Diagnosis and Countermeasure Flow Chart

Is installation

condition normal?

Yes

Are the resistance

Between each phase and

insulation resistance of Inverter

compressor normal?

Yes

Is compressor

Wire connection

condition normal?

Yes

Is inverter PCB assembly power connection normal?
Yes

Check connection between inverter PCB assembly and

bridge diode(misconnection, disconnection)

wiring again if abnormality found

Is input voltage normal? Yes

Check

L1~L2 phase is 230V 15%

Check connection condition and wiring if power is

abnormal

Is inverter PCB assembly

normal?

Yes Recheck power and installation condition

Check inverter PCB assembly IPM normality Replace inverter PCB assembly

- 62 -

LGE Internal Use Only

Part 5. Trouble Shooting
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
(18/24/30 kBtu/h class - Check output the CT Sensor : DC 2.5±0.2V) (36/42 kBtu/h class - Check output pin 1.2 of the CT Sensor : 5V )
18,24,30kBtu/h class

GND

36,42kBtu/h class

Black Red

I_IN

2.5V Vdc

< Inverter PCB>

- 63 -

LGE Internal Use Only

Display code

Title

Cause of error

· DC Link Voltage is

DC Link High / Low Volt

above 420Vdc · DC Link Voltage is

below 140Vdc

Part 5. Trouble Shooting
Check point & Normal condition
· Check CN_(L), CN_(N) Connection · Check Input Voltage · Check PCB DC Link voltage sensor parts

n Error Diagnosis and Countermeasure Flow Chart

Is input voltage normal ?
Yes
Is Inverter PCB assembly Power connection normal?

No Check L1~L2 Voltage is 230V±15%
No Check connection from terminal block to Inverter PCB assembly CN(L), CN(N)

Yes Is Inverter PCB Normal?

No Replace inverter PCB assembly

Yes
Recheck power and installation condition

- 64 -

LGE Internal Use Only

Part 5. Trouble Shooting
Check Point
1. Check the REACTOR_IN and REACTOR_OUT1,2 Connection condition at the Main PCB.(Refer to outdoor wiring diagram)
2. Measure the voltage as shown in figures. 3. If the measurements are significantly different from the levels shown in the figures, the PFCM is deemed to be
damaged.
18,24,30kBtu/h class
OUT
IN

IGBT

FRD

0.3 ~ 0.5 V Vdc

< IGBT >

Sequence of Measurement

Measurement

Normal Standards

C E 0.3V~0.5V

C : Collector / E : Emitter

Red Black

< FRD >

Sequence of Measurement

Measurement

Normal Standards

A C 0.3V~0.5V

A : Anode / C : Cathode

- 65 -

LGE Internal Use Only

36,42kBtu/h class

Part 5. Trouble Shooting
* Measuring input voltage

N L
(+) (-) <Inverter PCB>

- 66 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Input voltage

Cause of error

Check point & Normal condition

· Abnormal Input voltage · Check the power source.

(140Vac , 300Vac)

· Check the components.

n Error Diagnosis and Countermeasure Flow Chart

Is input voltage normal ?

No Check L1~L2 Voltage is 230V±15%

Yes Is Inverter PCB Normal?

No Replace inverter PCB assembly

Yes
Recheck power and installation condition

Check Point
1. Check the Input Voltage (L1~L2 ` 230V±10%) 2. Check Input Voltage Sensor output voltage (2.5Vdc±10%)

< Input Power Source Check Point >

- 67 -

LGE Internal Use Only

18,24,30kBtu/h class

INPUT(V) GND

Part 5. Trouble Shooting
GND

Black

INV_Current
2.5V Vdc
Red

<CT Sensing Check Point>
36,42kBtu/h class

Vdc INPUT(V)

GND

< Inverter PCB>

INPUT(V)

GND

< Input Voltage Sensing Check Point >

- 68 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

DC Compressor Position

Cause of error
· Compressor Starting fail error

Check point & Normal condition
· Check the connection of comp wire "U,V,W" · Malfunction of compressor · Check the component of "IPM", detection parts.

n Error Diagnosis and Countermeasure Flow Chart

Is installation condition normal?
Yes

1. Check Pipe clogging/distortion

2. Check Covering (Indoor/Outdoor Unit)

3. Check EEV connector assemble condition/normal

operation

4. Check refrigerant pressure

Reassemble or manage if abnormality found

Are the resistance

Between each phase and

insulation resistance of Inverter

compressor normal?

Yes

Is compressor Wire connection

condition normal?

Yes

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
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

Is inverter PCB assembly normal?

Check inverter PCB assembly IPM normality Replace inverter PCB assembly

Yes Recheck power and installation condition
18,24,30kBtu/h class

GND

Black

INV_Current
2.5V Vdc
Red

- 69 -

LGE Internal Use Only

Part 5. Trouble Shooting 36,42kBtu/h class
* Measuring resistance between each terminal of compressor * Compressor wire connection
U V W

- 70 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

AC Input Instant over

Current Error

Cause of error

Check point & Normal condition

1. Overload operation (Pipe clogging/Covering/EEV

defect/Ref. overcharge)

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

2. Compressor damage (Insulation damage/Motor damage)
3. Input voltage abnormal (L1,L2) 4. Power line assemble condition abnormal

5. Inverter PCB assembly Damage (input current

sensing part)

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 installation condition normal?
Yes

1.Check Pipe clogging/distortion

2.Check Covering (Indoor/Outdoor Unit)

3.Check EEV connector assemble condition/normal operation

4.Check refrigerant pressure

Reassemble or manage if abnormality found

No Is input voltage normal?
Yes

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

No Is AC input Wire connection
condition normal?
Yes

Is compressor

Wire connection

condition normal?

Yes

No Is inverter PCB assembly
normal?

Yes

1.Check L1,L2 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

Recheck power and installation condition
h PFCM Moudle checking method Set the multi tester to diode mode. Check short between input signal pin which are
placed below PFC Module. 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.

- 71 -

<Short Check Point>
LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Inverter compressor over current

Cause of error

Check point & Normal condition

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

n Error Diagnosis and Countermeasure Flow Chart

Is installation

condition normal?

Yes

Are the resistance

Between each phase and

insulation resistance of Inverter

compressor normal?

Yes

Is compressor

Wire connection

condition normal?

Yes

Is input voltage normal? Yes

Check

L1~L2 phase is 230V±15%

Check connection condition and wiring if power is

abnormal

Is inverter PCB assembly

normal?

Yes Recheck power and installation condition

Check inverter PCB assembly IPM normality Replace inverter PCB assembly

- 72 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Cause of error

Check point & Normal condition

· Overload operation (Out-

door fan constraint,

screened, blocked)

· Check outdoor fan constraint/ screened/ flow

High temperature in Dis- · Refrigerant leakage (in- structure

32 charge pipe of the inverter sufficient)

· Check refrigerant leakage

compressor

· Poor INV Comp Dis-

· Check if the sensor is normal

charge sensor

· Check the status of EEV assembly

· LEV connector displaced

/ poor LEV assembly

CN- DISCHARGE (BLACK 3Pin Connector)

Yes Replace the Thermistor

- 73 -

CN_TH3 (RED 4Pin Connector)
LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

35 Low Presser Error

Cause of error

Check point & Normal condition

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

Open service valve

Are communication cable/ No piping normal?
Yes

check communication/ piping correction.

Is amount of refrigerant

normal?

[refer refrigerant part]

Yes

Is there pipe crack or trace

of refrigerant leakage?

Yes

Weld / reconnect the cracked portion and recharge refrigerant

Adjust the amount of refrigerant (Additive charge)

Is strainer Ok?* Yes

No Replace the strainer

Are the value of manifold

gauge and pressure

sensor same?

(Is the low pressure value

actually low?)

Replace the pressure sensor

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

* 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)

- 74 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Cause of error

Transmission Error

Communication Error

39 Between (PFC Micom ' Between PFC Micom

INV Micom)

and INV Micom.

Check point & Normal condition
1. Micom defect/Circuit defect 2. Different Micom S/W Version 3. ODU inverter PCB assembly damage

n Error Diagnosis and Countermeasure Flow Chart

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

Upgrade Micom Program

Is Inverter PCB assembly normal?

No Replace inverter PCB assembly

Yes

Recheck power and installation condition

- 75 -

LGE Internal Use Only

Display code
40

Title
C/T Sensor Error

Cause of error · Initial current error

Part 5. Trouble Shooting
Check point & Normal condition
· Malfunction of current detection circuit. (Open / Short)
· Check CT Sensor output voltage : 2.5Vdc ±5%

n Error Diagnosis and Countermeasure Flow Chart

Is input voltage normal ?
Yes
Is Inverter PCB Normal?
Yes Recheck power and installation condition

No Check L1~L2 Voltage is 230V±15%
No Replace inverter PCB assembly

Check Point
1. Check the Input Voltage (L1~L2 ` 230V±10%) 2. Check Input Voltage Sensor output voltage (2.5Vdc±10%)

< Input Power Source Check Point >

- 76 -

LGE Internal Use Only

Part 5. Trouble Shooting 18,24,30kBtu/h class
GND

Black

INV_Current
2.5V Vdc
Red

36,42kBtu/h class Vdc

< Inverter PCB>

< CT Sensing Check Point >

- 77 -

LGE Internal Use Only

Display code

Title

Cause of error

· Open / Short 41 D-pipe sensor (Inverter) · Soldered poorly
· Internal circuit error

44 Air sensor

· Open / Short · Soldered poorly · Internal circuit error

Condenser Mid-pipesensor

· Open / Short · Soldered poorly · Internal circuit error

46 Suction Pipe sensor

· Open / Short · Soldered poorly · Internal circuit error

Condenser Out-pipe sensor

· Open / Short · Soldered poorly · Internal circuit error

Part 5. Trouble Shooting
Check point & Normal condition
1. Bad connection of thermistor connector 2. Defect of thermistor connector (Open/Short) 3. Defect of outdoor PCB
1. Bad connection of thermistor connector 2. Defect of thermistor connector (Open/Short) 3. Defect of outdoor PCB
1. Bad connection of thermistor connector 2. Defect of thermistor connector (Open/Short) 3. Defect of outdoor PCB
1. Bad connection of thermistor connector 2. Defect of thermistor connector (Open/Short) 3. Defect of outdoor PCB
1. Bad connection of thermistor connector 2. Defect of thermistor connector (Open/Short) 3. Defect of outdoor PCB

n Error Diagnosis and Countermeasure Flow Chart

Is sensor connected

to PCB correctly??

Yes

No Is sensor value correct?*

Yes

Replace corresponding outdoor unit PCB

Connect sensor to PCB correctly Replace sensor

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 200k at 25

Air sensor

: Normal Value of the resistor is 10k at 25

Cond. Mid-pipe sensor

: Normal Value of the resistor is 5k at 25

Suction pipe sensor

: Normal Value of the resistor is 5k at 25

Condenser Out-pipe sensor : Normal Value of the resistor is 5k at 25

- 78 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Sensor error of high pressure

Cause of error

Check point & Normal condition

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 pressure sensor OK?

(Check the value of

pressure sensor.

Cf. Output voltage is about

1.4V at 1500kPa)

Yes

Is sensor connected

to PCB correctly?

Yes

After replacement of outdoor

unit main PCB is the system

also abnormal?

Yes

Replace corresponding pressure sensor

Replace the pressure sensor Connect sensor to PCB correctly
END

- 79 -

LGE Internal Use Only

Display code

Title

51 Over capacity

Part 5. Trouble Shooting

Cause of error

Check point & Normal condition

· Over capacity Combination

· Check the indoor unit capacity. · Check the combination table.

Model A2UW18GFH0 A3UW24GFH0 A4UW30GFH0 A5UW36GFH0 A6UW42GFH0
Check Point
1. Check the indoor unit capacity. 2. Check the combination table.

Gross max.capacity 24k 33k 40k 48k 56k

Max.single indoor unit capacity 15k 24k 24k 24k 36k

- 80 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Communication

(Indoor ' Outdoor)

Cause of error · Communication poorly

Check point & Normal condition
· 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.

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 2M) 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.

· 36,42kBtu/h class 1. In Case of CH05, Check the Connection ' CN_POWER,
CN_COMM at the Main PCB 2. In Case of CH53, Check the Connection ' CN_COMM at the
Main PCB ' L1, L2 at the terminal block
N

· 18,24,30kBtu/h class 1. In Case of CH53, Check the Connection
' L1,L2 at the terminal block

CN-Power CN-COMM

< MAIN PCB >

L1 L2

< TERMINAL BLOCK >

L1 L2

- 81 -

LGE Internal Use Only

Display code

Title

Cause of error

Inverter PCB & Main EEPROM Access error EEPROM check sum error and Check SUM error

Part 5. Trouble Shooting
Check point & Normal condition
1. EEPROM contact defect/wrong insertion 2. Different EEPROM Version 3. ODU Inverter & Main PCB assembly damage

No Is EEPROM insertion normal?
Yes No
Is inverter PCB assembly normal?

1.Check EEPROM insert direction/connection condition 2.Check EEPROM Check SUM Replace if abnormality found
Replace inverter PCB assembly

Yes No
MAIN PCB assembly normal?

Replace MAIN PCB assembly

Yes Recheck power and installation condition

Check Point
- Check the EEPROM Check sum & Direction
18,24,30kBtu/h class

EEPROM

- 82 -

LGE Internal Use Only

Part 5. Trouble Shooting 36,42kBtu/h class

- 83 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

High temperature in outdoor Cond. Pipe

Cause of error

Check point & Normal condition

· Overload operation (Out-

door fan constraint,

screened, blocked)

· Check outdoor fan constraint / screened / flow

· Outdoor unit heat ex-

structure

changer contaminated · Check if refrigerant overcharged

· EEV connector displaced · Check the status of EEV assembly

/ poor EEV assembly

· Check the status of sensor assembly / burn

· Poor Cond. Pipe sensor

assembly / burned

CN- C/PIPE (Violet 3Pin Connector)

Yes Replace the Thermistor

- 84 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Heatsink High error

Cause of error

Check point & Normal condition

Inverter PCB heatsink temperature is over 85°C

1. ODU fan locking 2. Heatsink assembly of INV PCB assemble condi-
tion abnormal 3. Defect of temperature sensing circuit part defect
of INV PCB

n Error Diagnosis and Countermeasure Flow Chart

Is Installation

Condition Normal?

Yes
No Inv. PCB IGBTM Connection
Condition Normal?

1. Check Pipe Clogging/ Distortion 2. Check Covering (Outdoor/Indoor Unit) 3. Check EEV Connector Assemble Condition/Normal Operation 4. Check Refrigerant Pressure 5. Check Power Wire/ Connection Condition
Reassemble or Manage if abnormality Found
1. Check Inv. PCB Screw Connection Condition Reassemble or Manage if abnormality Found

Yes
No Is ODU Fan Motor Normal?

1. Check Outdoor Unit Fan Motor Operation or Lock Reassemble or Manage if abnormality Found

Yes
No Is Inv. PCB assembly
Normal?
Yes Recheck Power and Installation Condition

1. Reset Replace Inv. PCB Assembly

Check Point
1. Check resistance between No.19 pin and NO.20 pin of PCB PFC module 2. Resistance value should be in 7k ±10%.(at 25°C). 3. Check Inv. PCB Screw Connection Condition only 36,42kBtu/h class

- 85 -

LGE Internal Use Only

18,24,30kBtu/h class

Part 5. Trouble Shooting

Black Red

9~11K

PFCM :

Measuring resistance

between No.19,20 pin

36,42kBtu/h class

Check Screw Connection Condition

- 86 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Heatsink Sensor error

Cause of error
Inverter PCB heatsink sensor is open or short

Check point & Normal condition
1. ODU fan locking 2. Heatsink assembly of INV PCB assemble
condition abnormal 3. Defect of temperature sensing circuit part defect
of INV PCB

n Error Diagnosis and Countermeasure Flow Chart

Is installation condition normal ?
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

Is assemble condition

of INV PCB heatsink normal ?

Check assemble condition between INV PCB heatsink and IGBTM Module Reassemble if abnormality found

Yes
Is PCB temperature sensing part normal ?
Yes

Check resistance between NO.19 pin and NO.20 pin

of PFC module

Check resistance between NO.24 pin and NO.25 pin

of PFC module

7K 10%(at 25°C)

Replace PCB if abnormality found

Recheck installation condition and connection of Heat sink

Check Point
1. Check resistance between No.19 pin and NO.20 pin of PCB PFC module 2. Resistance value should be in 7k ±10%.(at 25°C). 3. Check the PFC Module No.19, 20.

- 87 -

LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Fan Lock Error

Cause of error

Check point & Normal condition

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 condi-
tion abnormal 3. Defect of temperature sensing circuit part defect
of INV PCB

n Error Diagnosis and Countermeasure Flow Chart

Is ODU Fan Motor Assemble

condition normal?

Yes

No Is ODU Fan Motor normal?

Yes

Is wire connection of

ODU Fan Motor wire normal?

Yes

No Is Inverter PCB assembly normal?

Check ODU Fan Motor assemble condition and fan locking Reassemble or replace if abnormality found
1. Set the multi tester to diode mode. 2. Check voltage between 1pin and 4pin of Fan Motor
(10.2V) 3. Replace Inverter PCB if abnormality found.
Check wiring between OUD fan motor and Inverter PCB ( Check if Hall Senor and Motor output terminal color is matched) Reassemble if abnormality found
Replace Inverter PCB assembly

Yes Recheck power and installation condition

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.

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LGE Internal Use Only

Part 5. Trouble Shooting 18,24,30kBtu/h class

-. Checking wire Check voltage betwen terminals for 1pin and 4pin of fan motor possible short

Fan motor connector

Tester

HQPEI@

d@ @

d@ d@ @ @

36,42kBtu/h class

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LGE Internal Use Only

Part 5. Trouble Shooting

Display code

Title

Cause of error

Check point & Normal condition

1. Overload operation (Pipe clogging/Covering/EEV

defect/Ref.overcharge)

AC input instant over current error
(Matter of software)

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

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)

n Error Diagnosis and Countermeasure Flow Chart

Is installation condition normal?
Yes

1.Check Pipe clogging/distortion

2.Check Covering (Indoor/Outdoor Unit)

3.Check EEV connector assemble condition/normal operation

4.Check refrigerant pressure

Reassemble or manage if abnormality found

No Is input voltage normal?
Yes

Check L1~L2 phase voltage is 230V ± 15% Check connection condition and wiring if power is abnormal

No Is AC input Wire connection
condition normal?
Yes

Is compressor

Wire connection

condition normal?

Yes

No Is inverter PCB assembly
normal?
Yes
Recheck power and installation condition

- 90 -

LGE Internal Use Only

Part 5. Trouble Shooting 18,24,30kBtu/h class

OUT IN
< Noise Filter wiring Check Point >
OUT
IN
< Main PCB wiring Check Point >

< Input Power Source Check Point >

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LGE Internal Use Only

36,42kBtu/h class

L2 L2 L1 L2 L1

Part 5. Trouble Shooting

L2 L1

L1 L2 < Noise Filter wiring Check Point >
L1 L2

< Main PCB wiring Check Point >

L2 L1

< Input Power Source Check Point >

< Inverter PCB wiring Check Point >

- 92 -

LGE Internal Use Only

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