LG S4NQ18KL25A User manual

www.lg.com
OWNER'S MANUAL
AIR
CONDITIONER
Read this owner's manual thoroughly before operating the appliance and keep
it handy for reference at all times.
TYPE: WALL MOUNTED
EN English FR Français PT Português
Copyright © 2017 LG Electronics Inc. All Rights Reserved.
MFL69781401
Rev.02_092617

TABLE OF CONTENTS This manual may contain images or
content different from the model you
purchased.
This manual is subject to revision by the
manufacturer.
SAFETY INSTRUCTIONS ................................................... 3
IMPORTANT SAFETY INSTRUCTIONS................................................3
OPERATION ....................................................................... 11
Notes for Operation .............................................................................. 11
Parts and Functions.............................................................................. 11
Wireless Remote Control......................................................................12
Restarting the Air Conditioner Automatically ........................................17
Using the Mode Function......................................................................17
Using the Jet Mode Function................................................................19
Using the Fan Speed Function.............................................................20
Using the Air Flow Direction Function...................................................20
Setting the On/Off Timer.......................................................................21
Using the Sleep Function (Optional).....................................................22
Using the Simple Timer Function (Optional).........................................22
Using the Energy Display Function (Optional)......................................23
Using the Light Off Function (Optional) ................................................23
Using the Comfort Air Function (Optional)............................................23
Using the Energy Saving Function (Optional) ......................................24
Using the Energy Control Function (Optional)......................................24
Using the Generator Mode Function (Optional)....................................25
Using Special Functions.......................................................................26
SMART FUNCTIONS......................................................... 29
Using LG SmartThinQ Application........................................................29
MAINTENANCE.................................................................. 32
Clean the Air Filter................................................................................34
Clean the 3M and Triple Filter (Optional)..............................................35
TROUBLESHOOTING ....................................................... 36

3
SAFETY INSTRUCTIONS EN
The following safety guidelines are intended to prevent
unforeseen risks or damage from unsafe or incorrect
operation of the appliance.
The guidelines are separated into ‘WARNING’ and ‘CAUTION’
as described below.
This symbol is displayed to indicate matters and
operations that can cause risk. Read the part with this
symbol carefully and follow the instructions in order to
avoid risk.
WARNING
This indicates that the failure to follow the instructions can
cause serious injury or death.
CAUTION
This indicates that the failure to follow the instructions can
cause the minor injury or damage to the product.
IMPORTANT SAFETY INSTRUCTIONS
WARNING
To reduce the risk of explosion, fire, death, electric shock,
injury or scalding to persons when using this product,
follow basic precautions, including the following:
Children in the Household
This appliance is not intended for use by persons (including
children) with reduced physical, sensory or mental capabilities, or
lack of experience and knowledge, unless they have been given
supervision or instruction concerning use of the appliance by a
person responsible for their safety. Children should be supervised
to ensure that they do not play with the appliance.

4
EN
Installation
•Do not install the air conditioner on an unstable surface or in a
place where there is danger of it falling.
•Contact an authorized service center when installing or relocating
the air conditioner.
•Install the panel and the cover of the control box safely.
•Do not install the air conditioner in a place where flammable
liquids or gases such as gasoline, propane, paint thinner, etc., are
stored.
•Make sure that the pipe and the power cable connecting the
indoor and outdoor units are not pulled too tight when installing
the air conditioner.
•Use standard circuit breaker and fuse that conform to the rating of
the air conditioner.
•Do not input air or gas into the system except with the specific
refrigerant.
•Use non-flammable gas (nitrogen) to check for leak and to purge
air; using compressed air or flammable gas may cause fire or
explosion.
•The 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.

5
EN
•Install dedicated electric outlet and circuit breaker before using the
air conditioner.
•Do not connect the ground wire to a gas pipe, a lightning rod, or a
telephone ground wire.
Operation
•Be sure to use only those parts listed in the service parts list.
Never attempt to modify the equipment.
•Make sure that children do not climb on or hit the outdoor unit.
•Dispose of the batteries in a place where there is no danger of
fire.
•Use only the refrigerant specified on the air conditioner label.
•Cut off the power supply if there is any noise, smell, or smoke
coming from the air conditioner.
•Do not leave flammable substances such as gasoline, benzene, or
thinner near the air conditioner.
•Contact an authorized service center when the air conditioner is
submerged by flood waters.
•Do not use the air conditioner for an extended period of time in a
small place without proper ventilation.
•In the event of a gas leak (such as Freon, propane gas, LP gas,
etc.) ventilate sufficiently before using the air conditioner again.
•To clean the interior, contact an authorized service center or
dealer. Using harsh detergents may cause corrosion or damage to
the unit.
•Be sure to ventilate sufficiently when the air conditioner and a
heating appliance such as a heater are used simultaneously.

6
EN
•Do not block the inlet or outlet of air flow.
•Do not insert hands or other objects through the air inlet or outlet
while the air conditioner is operating.
•Make sure that the power cable is neither dirty, loose, nor broken.
•Never touch, operate, or repair the air conditioner with wet hands.
•Do not place any objects on the power cable.
•Do not place a heater or other heating appliances near the power
cable.
•Do not modify or extend the power cable. Scratches or peeling
insulation on the power cables may result in fire or electric shock,
and should be replaced.
•Cut off the power supply immediately in the event of a blackout or
a thunderstorm.
•Take care to ensure that power cable could not be pulled out or
damaged during operation.
•Do not touch refrigerant pipe, water pipe and any internal parts
while the unit is operating or immediately after operation.
Maintenance
•Do not clean the appliance by spraying water directly onto the
product.
•Before cleaning or performing maintenance, disconnect the power
supply and wait until the fan stops.

7
EN
Technical Safety
•Installation or repairs made by unauthorized persons can pose
hazards to you and others.
•The information contained in the manual is intended for use by a
qualified service technician who is familiar with the safety
procedures and equipped with the proper tools and test
instruments.
•Failure to read and follow all instructions in this manual can result
in equipment malfunction, property damage, personal injury and/or
death.
•The appliance shall be installed in accordance with national wiring
regulations.
•When the power cord is to be replaced, the replacement work
shall be performed by authorized personnel using only genuine
replacement parts.
•This appliance must be properly grounded to minimize risk of
electric shock.
•Do not cut or remove the grounding prong from the power plug.
•Attaching the earth wire to the power outlet cover screw does not
ground the appliance unless the cover screw is metal, uninsulated,
and the power outlet is grounded through house wiring.
•If you have any doubt whether the air conditioner is properly
grounded, have the power outlet and circuit checked by a qualified
electrician.
•The refrigerant and insulation blowing gas used in the appliance
require special disposal procedures. Consult a service agent or a
similarly qualified person before disposing of them.
•If the supply cord is damaged, it must be replaced by the
manufacturer or its service agents or similarly qualified person in
order to avoid a hazard.

8
EN
CAUTION
To reduce the risk of minor injury to persons, malfunction,
or damage to the product or property when using this
product, follow basic precautions, including the following:
Installation
•Do not install the air conditioner in an area where it is directly
exposed to sea wind (salt spray).
•Install the drain hose properly for the smooth drainage of water
condensation.
•Exercise caution when unpacking or installing the air conditioner.
•Do not touch the leaking refrigerant during installation or repair.
•Transport the air conditioner with two or more people or use a
forklift.
•Install the outdoor unit such that it is protected from direct
sunlight. Do not place the indoor unit in a place where it is directly
exposed to sunlight via the windows.
•Safely dispose of packing materials such as screws, nails or
batteries using proper packaging after installation or repair.
•Install the air conditioner in a place where the noise from the
outdoor unit or the exhaust fumes will not inconvenience the
neighbors. Failure to do so may result in conflict with the
neighbors.

9
EN
Operation
•Remove the batteries if the remote control is not to be used for an
extended period of time.
•Make sure that the filter is installed before operating the air
conditioner.
•Be sure to check if there is a refrigerant leak after installing or
repairing the air conditioner.
•Do not place any object on the air conditioner.
•Never mix different types of batteries, or old and new batteries for
the remote control.
•Do not let the air conditioner run for a long time when humidity is
very high or when a door or a window has been left open.
•Stop using the remote control if there is a fluid leak in the battery.
If your clothes or skin are exposed to the leaking battery fluid,
wash off with clean water.
•Do not expose people, animals, or plants to the cold or hot wind
from the air conditioner for extended periods of time.
•If the leaking battery fluid has been swallowed, rinse the inside of
the mouth thoroughly and consult a doctor.
•Do not drink the water drained from the air conditioner.
•Do not use the product for special purposes, such as preserving
foods, works of art, and etc. It is an air conditioner for consumer
purposes, not a precision refrigeration system. There is risk of
damage or loss of property.
•Do not recharge or disassemble the batteries.

10
EN
Maintenance
•Never touch the metal parts of the air conditioner when removing
the air filter.
•Use a sturdy stool or ladder when cleaning, maintaining, or
repairing the air conditioner at a height.
•Never use strong cleaning agents or solvents when cleaning the
air conditioner or spray water. Use a smooth cloth.

11
OPERATION EN
Notes for Operation
Suggestion for Energy Saving
•Do not over-cool the space. This may be harmful for your health and may consume more
electricity.
•Block sunlight with blinds or curtains while you are operating the air conditioner.
•Keep doors or windows closed tightly while you are operating the air conditioner.
•Adjust the direction of the air flow vertically or horizontally to circulate indoor air.
•Speed up the fan to cool or warm indoor air quickly, within a short period of time.
•Open windows regularly for ventilation. The indoor air quality may deteriorate if the air conditioner
is used for long durations.
•Clean the air filter once every 2 weeks. Dust and impurities collected in the air filter may block the
air flow or reduce the unit performance.
Parts and Functions
Indoor Unit Outdoor Unit
Air Filter
Air Intake
Front Cover
Air Outlet
Air Deflector (Horizontal Vane)
Air Deflector (Vertical Louver)
On/Off Button
1
2
3
4
5
6
7
Air Intake Vents
Air Outlet Vents
1
2
NOTE
•The number and location of operation lamps may vary according to the model of the air
conditioner.
•The feature may be changed according to the type of model.

12
EN
Wireless Remote Control
Inserting Batteries
If the display screen of the remote control
begins to fade, replace the batteries. Insert AAA
(1.5 V) batteries before using the remote
control.
1Remove the battery cover.
2Insert the new batteries and make sure that
the + and - terminals of the batteries are
installed correctly.
Installing the Remote Control
Holder
To protect the remote control, install the holder
where there is no direct sunlight.
1Choose a safe and easily accessible
location.
2Fix the holder by fastening 2 screws firmly
with a screwdriver.
Operating Method
Point the remote control towards the signal
receiver at the right side of the air conditioner to
operate it.
NOTE
•The remote control may operate other
electronic devices if it is directed towards
them. Make sure to point the remote control
towards the air conditioner signal receiver.
•For proper operation, use a soft cloth to clean
the signal transmitter and receiver.
•In case of a function not provided in the
product, no buzzer sound occurs from the
product when a button for such function on
the remote control is pressed except for Air
Flow Direction (
SWING
), Energy Display (
kW [3 s]
),
Air Purification function ( ).

13
EN
Setting the Current Time
1Insert batteries.
•The icon below blinks at the bottom of the
display screen.
2Press or button to select the
minutes.
3Press SET/CANCEL button to finish.
NOTE
•The On/Off Timer is available after setting the
current time.
Using the °C/°F Conversion
Function (Optional)
This function changes unit between °C and °F
•Press and hold
℃↔℉ [5 s]
SWING
button about 5 seconds.
Operating the Air Conditioner
without the Remote Control
You can use the ON/OFF button of the indoor
unit to operate the air conditioner when the
remote control is unavailable.
1Open the front cover (Type2) or horizontal
vane (Type1).
2Press the ON/OFF button.
Type1
ON/OFF
Type2
ON/OFF
NOTE
•The stepping motor may be broken, if the
horizontal vane opens rapidly.
•The fan speed is set to high.
•The feature may be changed according to the
type of model.
•The temperature cannot be altered when
using this emergency On/Off button.
•For cooling-only models, the temperature is
set to 22 °C
•For cooling & heating models, the temperature
is set from 22 °C to 24 °C

14
EN
Using Wireless Remote Control
You can operate the air conditioner more conveniently with the remote control.
SWING
kW [3 s]
℃↔℉ [5 s] DIAGNOSIS [5 s]
SWING
SET UP
ROOM
TEMP
JET
MODE
MODE
TEMP
FAN
SPEED
FUNC.
TIMER CANCEL
SET
CANCEL
*
*
1
2
*
RESET
Button Display
Screen Description
-To turn on/off the air conditioner.
To adjust the desired room
temperature in cooling, heating or auto
changeover mode.
MODE
To select the cooling mode.
To select the heating mode.
To select the dehumidification mode.
To select the fan mode.
To select the auto changeover/auto
operation mode.
JET
MODE To change room temperature quickly.
FAN
SPEED To adjust the fan speed.
SWING
SWING
To adjust the air flow direction
vertically or horizontally.
NOTE
•* buttons may be changed according to the type of model.

15
EN
SWING
kW [3 s]
℃↔℉ [5 s] DIAGNOSIS [5 s]
SWING
SET UP
ROOM
TEMP
JET
MODE
MODE
TEMP
FAN
SPEED
FUNC.
TIMER CANCEL
SET
CANCEL
*
*
1
2
*
RESET
Button Display
Screen Description
TIMER
To turn on/off air conditioner
automatically at desired time.
SET/
CANCEL -To set/cancel the special functions and
timer.
CANCEL
-To cancel the timer settings.
-To adjust time.
*LIGHT
OFF -To set the brightness of the display on
the indoor unit.
ROOM
TEMP To display the room temperature.
°C↔°F [5 s] To change unit between °C and °F
*ENERGY
SAVING To minimize power consumption.
*COMFORT
AIR To adjust the air flow to deflect wind.
kW [3 s] -To set whether or not to display
information regarding energy.
*ENERGY
CTRL To bring the effect of the power saving.
*COMFORT
SLEEP
To make a comfortable sleeping
environment.
DIAGNOSIS
[5 s] -To conveniently check maintenance
information of a product.
*GEN
MODE -To operate air conditioner under the
previously set power consumption.

16
EN
SWING
kW [3 s]
℃↔℉ [5 s] DIAGNOSIS [5 s]
SWING
SET UP
ROOM
TEMP
JET
MODE
MODE
TEMP
FAN
SPEED
FUNC.
TIMER CANCEL
SET
CANCEL
*
*
1
2
*
RESET
Button Display
Screen Description
FUNC.
To purify the air by removing particles
that enters the indoor unit.
To reduce noise from outdoor units.
To keep your skin moisturized by
generating ion clusters.
To lower indoor humidity quickly.
To maintain a minimum room
temperature and prevent objects in the
room from freezing.
To scare away a mosquito.
To remove moisture generated inside
the indoor unit.
To make a comfortable sleeping
environment.
RESET - To initialize the remote control settings.
NOTE
•Some functions may not be supported, depending on the model.
•* buttons may be changed according to the type of model.
•Press the SET/CANCEL button to operate the selected FUNC.

17
EN
Restarting the Air Conditioner
Automatically
When the air conditioner is turned on again
after a power failure, this function restores the
previous settings.
Disabling Auto Restart
1Open the front cover (Type2) or horizontal
vane (Type1).
2Press the ON/OFF button and hold it for 6
seconds, then the unit will beep twice and
the lamp will blink twice 4 times.
•To re-enable the function, press the ON/
OFF button and hold it for 6 seconds. The
unit will beep twice and the lamp will blink
4 times.
Type1
ON/OFF
Type2
ON/OFF
NOTE
•The feature may be changed according to the
type of model.
•If you press and hold the ON/OFF button for 3
– 5 seconds, instead of 6 seconds, the unit
will switch to the test operation. In the test
operation, the unit blows out strong cooling air
for 18 minutes and then returns to factory
default settings.
Using the Mode Function
This function allows you to select the desired
function.
Cooling Only Model
Cooling Mode
Auto Operation(AI) Mode
Dehumidification Mode
Fan Mode
Cooling & Heating Model
Cooling Mode
Auto Changeover Mode
Dehumidification Mode
Heating Mode
Fan Mode
Cooling Mode
1Turn the appliance on.
2Press MODE button repeatedly to select the
Cooling Mode.
•is displayed on the display screen.
3Press or button to set the desired
temperature.

18
EN
Heating Mode
1Turn the appliance on.
2Press MODE button repeatedly to select the
Heating Mode.
•is displayed on the display screen.
3Press or button to set the desired
temperature.
NOTE
•will be displayed on the indoor unit when
defrosting is operating.
•Furthermore, this indication will be displayed
on the indoor unit:
−When preheating is operating.
−When the room temperature has been
reached to the set temperature.
Dehumidification Mode
This mode removes excess moisture from a
highly humid environment or during the rainy
season, in order to prevent mildew from setting
in. This mode adjusts the room temperature and
the fan speed automatically to maintain the
optimal level of humidity.
1Turn the appliance on.
2Press MODE button repeatedly to select the
Dehumidification Mode.
•is displayed on the display screen.
NOTE
•In this mode you cannot adjust the room
temperature, it is adjusted automatically.
•The room temperature is not displayed on the
display screen.
Fan Mode
This mode only circulates the indoor air without
changing the room temperature.
1Turn the appliance on.
2Press MODE button repeatedly to select the
Fan Mode.
•is displayed on the display screen.
3Press FAN SPEED button to adjust the fan
speed.
Auto Changeover Mode
Cooling & Heating Model
This mode changes the mode automatically to
maintain the set temperature at ±2 °C
1Turn the appliance on.
2Press MODE button repeatedly to select the
Auto Changeover Mode.
•is displayed on the display screen.
3Press or button to set the desired
temperature.
4Press FAN SPEED button to adjust the fan
speed.

19
EN
Auto Operation (Artificial
Intelligence)
Cooling Only Model
This mode automatically sets the fan speed and
temperature depending on the room
temperature.
1Turn the appliance on.
2Press MODE button repeatedly to select the
Auto Operation.
•is displayed on the display screen.
3Press or button to select the desired
operation code if the temperature is higher
or lower than the desired temperature.
Code Description
2 Cold
1A little cold
0Maintain room temperature
-1 A little hot
-2 Hot
NOTE
•In this mode, you cannot adjust the fan speed,
but you can set the air deflector to rotate
automatically.
Using the Jet Mode Function
Changing Room Temperature
Quickly
This function allows you to cool indoor air
quickly during the summer or warm it quickly
during winter.
•Cooling & Heating model : The Jet Mode
function is available with Cooling, Heating and
Dehumidification Mode.
•Cooling Only model : The Jet Mode function is
available with Cooling, Dehumidification, Fan,
Auto Operation Mode and Air Purification
function.
1Turn the appliance on.
2Press MODE button repeatedly to select the
desired mode.
3Press JET MODE button.
•is displayed on the display screen.
NOTE
•Jet Heating Mode is not available on some
models.
•In Jet Cooling Mode, strong air blows out for
30 minutes.
•After 30 minutes later, setting temperature is
maintaining 18 °C
If you want to change the temperature, Press
or button to set the desired
temperature.
•In Jet Heating Mode, strong air blows out for
30 minutes.
•After 30 minutes later, setting temperature is
maintaining 30 °C
If you want to change the temperature, Press
or button to set the desired
temperature.
•This function may operate differently from the
remote control display.

20
EN
Using the Fan Speed
Function
Adjusting the Fan Speed
•Press FAN SPEED button repeatedly to adjust
the fan speed.
Display Screen Speed
High
Medium - High
Medium
Medium - Low
Low
-Natural Wind
NOTE
•The fan speed of Natural Wind adjusts
automatically.
→ →
•The fan speed icons are displayed on some
indoor units.
→ → → →
•Indoor unit display is displayed only 5 seconds
and return to the setting temperature on some
models.
Using the Air Flow Direction
Function
This function adjusts the direction of the air flow
vertically (horizontally).
•Press
SWING
(
SWING
) button repeatedly and select
the desired direction.
−Select () to adjust the direction of the
air flow automatically.
NOTE
•Adjusting the air flow direction horizontally
may not be supported, depending on the
model.
•Adjusting the air deflector arbitrarily may
cause product failure.
•If you restart the air conditioner, it starts to
operate with the previously set direction of air
flow, so the air deflector may not match the
icon displayed on the remote control. When
this occurs, press
SWING
or
SWING
button to
adjust the direction of the air flow again.
•This function may operate differently from the
remote control display.