LG A2UW18GFA0 User manual

Multi Air Conditioner
SVC MANUAL(General)
MODEL : Multi-Inverter Type
CAUTION
Before Servicing the unit, read the safety precautions in General SVC manual.
Only for authorized service personnel.
Internal Use Only
http://biz.lgservice.com

- 1 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Air Conditioner Service Manual
TABLE OF CONTENTS
Part 1 General Information ..........................................................................................................2
1. Safety Precautions........................................................................................................3
2. Model Line Up................................................................................................................6
3. Nomenclature ................................................................................................................9
Part 2 Functions & Controls......................................................................................................11
1. List of Functions & Accessory ..................................................................................12
2. Air Flow .......................................................................................................................14
3. Air Purifying.................................................................................................................16
4. Installation Functions.................................................................................................17
5. Reliability .....................................................................................................................18
6. Convenience Functions & Controls .........................................................................19
7. Special Function & KIT...............................................................................................26
Part 3 Basic Control ..................................................................................................................29
1. Normal operation ........................................................................................................30
2 Compressor control ....................................................................................................30
3. EEV( Electronic Expansion Valve) control ...............................................................30
4. Oil return control ........................................................................................................31
5. Defrost control ...........................................................................................................31
6. Protection control ......................................................................................................32
Part 4 Test Run..........................................................................................................................33
1. Check before Test Run .............................................................................................34
2. Test Run Flow chart ..................................................................................................35
3. Test Runing.................................................................................................................36
Part 5 Trouble Shooting Guide ...............................................................................................38
1. Self-diagnosis Function .....................................................................................39
2. Pump Down .........................................................................................................41
3. Evacuation...........................................................................................................42
4. Gas Charging ......................................................................................................43
5. Cycle Part ............................................................................................................44
6. Electronic Parts...................................................................................................45
Part 6 Service Order.................................................................................................................110
1. PCB Service Order ...................................................................................................111

- 2 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
1. Safety Precautions ............................................................................................................3
2. Model Line Up .....................................................................................................................6
3. Nomenclature......................................................................................................................9
Part 1 General Information

Part 1 General Information
- 3 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
1. Safety Precautions
1.1 Cautions in Repair
To prevent injury to the user or other people and property damage, the following instructions must be followed.
■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.
■Meanings of symbols used in this manual are as shown below.
Be sure not to do.
Be sure to follow the instruction.
Dangerous Voltage
Be sure to disconnect the power cable plug from the plug socket before disas-
sembling the equipment for a repair.Internal components and circuit boards are at
main potential when the equipment is connected to the power cables. This volt-
age is extremely dangerous and may cause death or severe injury if come in con-
tact with it.
Do not touch the discharging refrigerant gas during the repair work.
The discharging refrigerant gas.The refrigerant gas can cause frostbite.
Release the refrigerant gas completely at a well-ventilated place first.
Otherwise, when the pipe is disconnected, refrigerant gas or refrigerating
machine oil discharges and it Can cause injury.
When the refrigerant gas leaks during work, execute ventilation. If the refrigerant
gas touches to a fire, poisonous gas generates. A case of leakage of the refriger-
ant and the closed room full with gas is dangerous because a shortage of oxygen
occurs. Be sure to execute ventilation.
When removing the front panel or cabinet, execute short-circuit and discharge
between high voltage capacitor terminals. If discharge is not executed, an electric
shock is caused by high voltage resulted in a death or injury.
Do not turn the air-conditioner ON or OFF by plugging or unplugging the power
plug. There is risk of fire or electrical shock.

Part 1 General Information
- 4 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Do not turn on the breaker under condition that front panel and cabinet are
removed.
Be sure to earth the air conditioner with an earthing conductor connected to the
earthing terminal.
Conduct repair works after checking that the refrigerating cycle section has
cooled down sufficiently. Otherwise, working on the unit, the hot refrigerating
cycle section can cause burns.
Do not tilt the unit when removing panels. Otherwise, the water inside the unit
can spill and wet floor.
Do not use the welder in a well-ventilated place. Using the welder in an enclosed
room can cause oxygen deficiency.
Be sure to turn off power switch before connect or disconnect connector, or parts
damage may be occurred.
Do not use a defective or underrated circuit breaker. Use the correctly rated
breaker and fuse. Otherwise there is a risk of fire or electric shock.
Install the panel and the cover of control box securely. Otherwise there is risk of
fire or electric shock due to dust, water etc.
Indoor/outdoor wiring connections must be secured tightly and the cable should
be routed properly so that there is no force pulling the cable from the connection
terminals. Improper or loose connections can cause heat generation or fire.
Do not touch, operate, or repaire the product with wet hands. Hoding the plug by
hand when taking out. Otherwise there is risk of electric shock or fire.
Use a vacuum pump or Inert (nitrogen) gas when doing leakage test or air
purge. Do not compress air or Oxygen and Do not use Flammable gases.
Otherwise, it may cause fire or explosion.
- There is the risk of death, injury, fire or explosion.

Part 1 General Information
- 5 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
1.2 Inspections after Repair
Check to see if the parts are mounted correctly and wires are connected.
Improper installation and connections can cause an electric shock or an injury.
Check the installation platform or frame has corroded. Corroded installation plat-
form 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 resis-
tance 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.
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 prod-
uct 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

2. Model Line Up
Part 1 General Information
- 6 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
2.1 Indoor units
* Indicates color of panel – ART COOL : Gold(G), White Silver(H), Blue(B), Gallery(1)
ART COOL Mirror : Mirror(R), Silver(V), White(W)
Category Chassis
Model names
Capacity, kW(kBtu/h Class)
2.1(7) 2.6 (9) 3.5 (12) 4.2(15) 5.3 (18) 7.03 (24) 10.6 (36)
Wall mounted SB
AMNW07GDBL1
[LMN077HVT]
AMNW09GDBL1
[LMN097HVT]
AMNW12GDBL1
[LMN127HVT]
AMNW15GDBL1
[LMN157HVT]
SC
AMNW18GDCL1
[LMN187HVT]
AMNW24GDCL1
[LMN247HVT]
ART COOL Mirror SB
AMNW09GDBR1
[LMAN097HVT]
AMNW12GDBR1
[LMAN127HVT]
SC
AMNW18GDCR1
[LMAN187HVT]
ART COOL Gallery
SF
AMNW09GAF11
[LMAN097HVP]
AMNW12GAF11
[LMAN127HVP]
Ceiling
cassette
4-way TR
AMNW07GTRA0
[LMCN077HV]
AMNW09GTRA0
[LMCN097HV]
AMNW12GTRA0
[LMCN125HV]
TQ
AMNW18GTQA0
[LMCN185HV]
Ceiling
concealed
duct
Low static pressure
(Slim)
L1
AMNW09GL1A0
[LMDN096HV]
L2
AMNW12GL2A0
[LMDN126HV]
AMNW18GL2A0
[LMDN186HV]
High Static pressure
BG
AMNW24GBGA0
[LMHN240HV]
AMNW36GBGA0
[LMHN360HV]
Vertical AHU
NJ
AMNW24GNJA0
[LMVN240HV]
AMNW36GNJA0
[LMVN360HV]

- 7 -
Part 1 General Information
2.2 Outdoor units
Copyright ©2012 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Multiple Piping Type
Branch Distribution type
Model Name A2UW18GFA0
[LMU18CHV]
A3UW24GFA0
[LMU24CHV]
A4UW36GFA0
[LMU36CHV]
No. of connectable indoor units (Min. ~ Max.) 2 ~ 2 2 ~ 3 2 ~ 4
Total capacity index of connectable indoor units 24 33 48
Power supply 208/230V, 1Ø, 60Hz
Chassis
Model Name A8UW54GFA0[LMU540HV]
No. of connectable indoor units (Min. ~ Max.) 2 ~ 8
Total capacity index of connectable indoor units 73
Power supply 208/230V, 1Ø, 60Hz
Chassis

- 8 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
2.3 BD(Branch distributor) units
Part 1 General Information
2.4 Branches
Branch
Type
No. of BD
Units
Accessory
Model Name
Applicable
Model
Specifications
Gas Liquid
Y-
Branch
2 PMBL5620
MULTI FMAX
To BD unit Ø19.05 (3/4)
Ø19.05 (3/4)
To ODU
Ø19.05 (3/4)
To BD unit Ø9.52 (3/8)
Ø9.52 (3/8)
To ODU
Ø9.52 (3/8)
No. of connectable indoor units(Min. ~ Max.) 1 ~ 2 1 ~ 3 1 ~ 4
Model name PMBD3620 PMBD3630 PMBD3640 PMBD3641
Connectable indoor unit capacity kBtu/h 9 ~ 24 9 ~ 24 9 ~ 24 9 ~ 36
BD unit

- 9 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Part 1 General Information
3. Nomenclature
3.1 Indoor Unit(Global)
AMN W G07 BDL0
Serial number
A4U W G24 F A 0
Electrical rating
Indicates that this is multi system indoor unit using R410A
Model type
H : Heat pump
W : DC Inverter heat pump
Ex) 7,000 Btu/h Class →'07', 18,000 Btu/h Class →'18'
Cooling/heating capacity
Electrical rating
G: 1ø, 220-240V, 50Hz/60Hz
L : 3ø, 380-415V, 50/60Hz
Chassis naem(Only Multi)
Indoor unit type(Only Multi)
A : ART COOL Gallery
D : Wall Mounted, ART COOL Mirror
T : Ceiling cassette, B : Ceiling concealed duct
N : Vertical AHU
Function
A : Basic, L : Plasma (Wall mounted)
C : Plasma(ceiling cassette)
Front panel design/color of ART COOL type
R : Mirror, 1 : Gallery
Indicates that this is multi system outdoor unit using R410A
Ex) A4U : Connectable max. 4 indoor units
A9U : Connectable max. 9 indoor units
Model type
W : DC inverter heat pump
Ex) 24,000 Btu/h Class →'24', 48,000 Btu/h Class →'48'
Cooling/heating capacity
G:1ø, 220-240V, 50/60Hz
L: 3ø, 380-415V, 50/60Hz
Multi type
Function
A : Basic
F : Free joint multi type
Serial number
3.2 Outdoor Unit(Global)

Part 1 General Information
- 10 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
P M BD 36 2 0
Serial number
Number of connectable indoor units
Max. capacity of connectable indoor units
“36” mean that 5k~24k Indoor unit connected to BD unit
BD : Branch distributor
M : Multi system outdoor unit
P : Parts
3.3 BD units(Global)

- 11 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Part 2 Functions & Controls
1. List of Functions & Accessory......................................................................................12
2. Air flow ............................................................................................................................14
2.1 Auto swing (left & right) ...............................................................................................14
2.2 Auto swing (up & down) ..............................................................................................14
2.3 Chaos swing (up/down)...............................................................................................14
2.4 Air flow step.................................................................................................................15
2.5 Chaos wind (auto wind)...............................................................................................15
2.6 Jet Cool Mode Operation ............................................................................................15
2.7 Swirl wind Swing .........................................................................................................15
3. Air purifying ....................................................................................................................16
3.1 PLASMA Air Purifying System ....................................................................................16
4. Installation Functions ....................................................................................................17
4.1 E.S.P. (External Static Pressure) Setting ....................................................................17
5. Reliability ........................................................................................................................18
5.1 Hot start.......................................................................................................................18
5.2 Self-diagnosis Function...............................................................................................18
5.3 Soft dry operation........................................................................................................18
6. Convenience Functions & Controls .............................................................................19
6.1 Cooling & heating Operations ....................................................................................19
6.2 Auto cleaning operation ..............................................................................................20
6.3 Auto Operation (Artificial Intelligence).........................................................................20
6.4 Auto restart Opeartion.................................................................................................21
6.5 Child Lock Function.....................................................................................................22
6.6 Forced operation .........................................................................................................22
6.7 Group Control..............................................................................................................23
6.8 Sleep Timer Operation ................................................................................................24
6.9 Timer(On/Off) ..............................................................................................................24
6.10 Weekly Program........................................................................................................24
6.11 Two Thermistor Control .............................................................................................25
7. Special Function & KIT ..................................................................................................26
7.1 Low Ambient control....................................................................................................26
7.2 Space Control .............................................................................................................26
7.3 Auto Elevation Grille....................................................................................................26
7.4 Defrost Control(Heating) .............................................................................................28
Part 2 Functions & Controls

- 12 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
[Note]
O : Applied, X : Not applied
Accessory model name : Installed at field, ordered and purchased separately by the corresponding model name, sup-
plied with separate package.
Part 2 Functions & Controls
1. List of Functions & Accessory
1.1 List of Functions
• Indoor
Category Functions Wall Mounted ART COOL Mirror ART COOL
Gallery
Ceiling cassette
4-way
Ceiling concealed
duct (Low static
pressure)
Ceiling concealed
duct (High static
pressure)
Vertical Air
Handling Unit
Air flow
Air supply outlet 1 1 3 4 1 1 1
Airflow direction control (left & right) Auto Auto Auto X X X X
Airflow direction control (up & down) Auto Auto Auto Auto X X X
Auto swing (left & right) O O O X X X X
Auto swing (up & down) O O O O X X X
Airflow steps (fan/cool/heat) 6 / 6 / 6 6 / 6 / 6 5 / 5 / 5 4 / 5 / 4 3 / 3 / 3 3 / 3 / 3 3 / 3 / 3
Chaos wind(auto wind) O O O O X X X
Jet cool/heat O / O O / O O / O O / X X / X X / X X / X
Swirl wind X X X O X X X
Air purify-
ing
Triple filter (Deodorizing) X X X X X X X
Ventilation Kit - - - PTVK430 X X X
Plasma air purifier O O X PTPKQ0 X X X
Allergy Safe filter X X X X X X X
Long-life prefilter (washable / anti-fung O O O O O O X
Installation
Drain pump X X X O O O X
E.S.P. control X X X X O O O
Electric heater X X X X X X
ANEH053B1(5kW)
ANEH103B2(10kW)
High ceiling operation X X X O X X X
Auto Elevation Grille X X X X X X X
Reliability
Hot start O O O O O O O
Self diagnosis O O O O O O O
Soft dry operation O O O O O O O
Convenien
ce
Auto changeover X X X X X X X
Auto cleaning O O O X X X X
Auto operation(artificial intelligence) O O O O O O O
Auto Restart O O O O O O O
Child lock* O O O O O O O
Forced operation O O O O X X X
Group control* O O O O O O O
Sleep mode O O O O O X O
Timer(on/off) O O O O O X O
Timer(weekly)* O O O O O X O
Two thermistor control* O O O O O O O
Individual
control
Standard Wired remote controller PREMTB10U
Deluxe wired remote controller X X X X X X X
Simple wired remote controller PQRCVCL0Q / PQRCVCL0QW O O O
Simple wired remote controller(for hotel use) X X X X X X X
Wireless remote controller* O O O O PQWRHQ0FDB
Network
function
General central controller (Non LGAP X X X X X X X
Network Solution(LGAP) O O O O O O O
Dry contact PQDSA(1)/PQDSB(1) / PQDSBC / PQDSBNGCM1
PI 485(for Indoor Unit) X X X X X X X
Special
function kit
Zone controller X X X X X X X
CTI(Communication transfer interface X X X X X X X
Electronic thermostat X X X X X X X
Others
Remote temperature sensor X X X PQRSTA0
Group control wire PZCWRCG3
Telecom shelter controller X X X X X X X
Connector for water level sensor O X O X X X X

- 13 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Part 2 Functions & Controls
[Note]
○: Applied, × : Not applied
* Option : Model name & price are different according to options, and assembled in factory with main unit.
Accessory model name : Installed at field, ordered and purchased separately by the corresponding model name, sup-
plied with separate package.
• Outdoor
Category Functions Remark
Reliability
Defrost / Deicing O
High pressure switch X
Low pressure switch X
Phase protection X
Restart delay (3-minutes) O
Self diagnosis O
Soft start O
Test function X
Convenience Night Silent Operation O
Network function Network solution(LGAP) O
1.2 List of Accessory
Device Remark
Central Controller
Simple Controller X
Function controller X
Function Scheduler X
AC Ez PQCSZ250S0
AC Smart ll PQCSW320A1E
Option Kit (SD card type) PQCSE341A0 / PQCSE342A0
ACP(Advanced Control Platform) PQCPA11A0E / PQCPB11A0E
AC Manager X
PI485 PMNFP14A0/PMNFP14A1
DO(Digital Output) Kit PQNFP00T0
BNU LONWORKS Gateway PQNFB16A1
(Building Network Unit) BACnet Gateway PQNFB17B0
Installation
Y branch Accessory
Header branch Accessory
Air Guide X
ODU Dry Contact X
Low Ambient Kit O (Logical operation)

- 14 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Part 2 Functions & Controls
2. Air flow
2.1 Auto swing (left & right)
RightLeft
110°~ 120°
Open
Close
110°~ 120°
Mode2
Mode3
Mode4
Mode5
Mode6
Mode7
Mode8
Mode9
OPEN
CLOSED
7~8°
110~120°
• By the horizontal airflow direction control key input, the left/right louver automatically operates with the auto swing or it
is fixed to the desired direction.
2.2 Auto swing (up & down)
• By the auto swing key input, the upper/lower vane automatically operates with the auto swing or it is fixed to the
desired direction.
2.3 Chaos swing (up/down)
• By the Chaos swing key input, the upper/lower vane automatically operates with the chaos swing or it is fixed to the
desired direction.
NOTE: Some Models are different by swing width and swing pattern.

- 15 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes 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.
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 operat-
ed.
• In the Jet Cool mode, the indoor fan is operated at super-high speed for 30 min. at cooling mode operation.
• In the Jet Cool mode operation, the room temperature is controlled to the setting temperature, 18°C.
• When the sleep timer mode is input while in the Jet Cool mode operation, the Jet Cool mode has the priority.
• When the Jet Cool key is input, the upper/lower vanes are reset to those of the initial cooling mode and then operated
in order that the air outflow could reach further.
2.7 Swirl wind Swing
• It is the function for comfort cooling/heating operation.
• The diagonal two louvers are opened the more larger
than the other louvers. After one minute, it is opposite.
• Comparison of Air Flow Types
4-Open (conventional) Swirl Swing (New)
LL Very low, In heating mode
L Low
M Med
H High
SH Super high
Auto Chaos wind
Step Discription
Vane 4
Vane 2
Vane 1 Vane 3

- 16 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Part 2 Functions & Controls
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.
3. Air purifying
Ionizer Photo-Catalyst Coated Mesh
Dust particles
Odour
Dust electrode discharge
Odour molecule
Generating plasma
+
+
+
+
Polluted Air Purified fresh Air
+4.8KV discharge
+

- 17 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Part 2 Functions & Controls
4.1 E.S.P. (External Static Pressure) Setting
4. Installation Functions
This is the function that decides the strength of the wind for each wind level and because this function is to make
the installation easier.
• If you set ESP incorrectly, the air conditioner may malfunction.
• This setting must be carried out by a certificated-technician.
TEMP
FAN
SPEED
OPER
MODE
When pressing the button and button
simultaneously for more than 3 seconds, the system will be
entered into the installer setting mode.
- After entering into the installer setting mode, select the
E.S.P code value by pressing the button.
* E.S.P code value : 03
1
Select the desired air flow rate with
the button. Whenever pressing
the button, [SLo
→ Lo → Med → Hi → Po] will be indicated.
2
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.
3
When pressing the button, currently established E.S.P
value will be set up.
4
When pressing the button and button simultaneously for
more than 3 seconds after the setting has been completed, the
setting mode will be released.
- If there isn’t any button input for more than 25 seconds, the
installer setting mode will also be released.
5
OPER
MODE
OPER
MODE
FAN
SPEED
FAN
SPEED
OPER
MODE
• 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.

- 18 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
5.1 Hot start
• When heating is started, the indoor fan is stopped or very slow to prevent the cold air carry out
• When the temp. of heat exchanger reach 30°C(model by model), indoor fan is started.
5.2 Self-diagnosis Function
• The air conditioner installed can self-diagnosed its error status and then transmits the result to the central control.
Therefore, a rapid countermeasure against failure of the air conditioner allows easy management and increases the
usage life of air conditioner.
• Refer to trouble shooting guide.
5.3 Soft dry operation
• When the dehumidification operation input by the remote control is received, the intake air temperature is detected and
the setting temp is automatically set according to the intake air temperature.
• While compressor off, the indoor fan repeats low airflow speed and stop.
• While the intake air temp is between compressor on temp. and compressor off temp., 10-min dehumidification opera-
tion and 4-min compressor off repeat.
Compressor ON Temp. ➔Setting Temp+0.5°C
Compressor OFF Temp. ➔Setting Temp-0.5°C
• In 10-min dehumidification operation, the indoor fan operates with the low airflow speed.
5. Reliability
Intake air Temp. Setting Temp.
26°C ≤ intake air temp. 25°C
24°C ≤ intake air temp.< 26°C intake air temp. -1°C
22°C ≤ intake air temp. < 24°C intake air temp. -0.5°C
18°C ≤ intake air temp. < 22°C intake air temp.
intake air temp. < 18°C 18°C
Part 2 Functions & Controls

- 19 -
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
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. Convenience Functions & Controls
6.1.2 Heating Mode
• Operating frequency of compressor depend on the load condition, The difference between the room temp. and set
temp., frequency restrictions.
• If compressor operates at some frequency, the operating frequency of compressor cannot be changed within 30 sec-
onds.
• Condition of compressor turned off
- When intake air temperature reaches +4°C above the setting temperature.
• Condition of compressor turned on
- When intake air temperature reaches +2°C above the setting temperature.
* Condition of indoor fan turned off
- While in compressor on : indoor pipe temp. < 20°C
- While in compressor off : indoor pipe temp. < 30°C
• While in defrost control, between the indoor and outdoor fans are turned off.
• Compressor 2minutes delay
- After compressor off, the compressor can restart minimum 2 minutes later.
CST/Duct type indoor unit matched with
Universal Outdoor unit
CST/ Duct/CVT type indoor unit
matched with Single Outdoor unit/Multi
Outdoor unit/Multi V Outdoor unit
Thermo ON : +2 °C above setting temp.
Thermo OFF : +4 °C above setting temp.
Thermo ON : Setting temp.
Thermo OFF : +3 °C above setting temp.
NOTE: Some Models are different by temperature of thermo ON/OFF.