LG R410A User manual

System
Air Conditioner
SERVICE MANUAL R410A
LG
MODELS: ARUN/ARUV Series
ARNU Series
website http://www.lgservice.com
CAUTION
• BEFORE SERVICING THE UNIT, READ THE SAFETY
PRECAUTIONS IN THIS MANUAL.
• ONLY FOR AUTHORIZED SERVICE PERSONNEL.

2
Air Conditioner Service Manual
TABLE OF CONTENTS
Safety Precautions .......................................................................................3
Model Names ..............................................................................................11
External Appearance ..................................................................................12
Nomenclature..............................................................................................14
Outdoor Units Information.........................................................................15
Indoor Units...........................................................................................17
Ceiling Mounted Cassette Type (4 way)....................................................19
Art Cool Type ............................................................................................31
Art Cool Type(Wide)..................................................................................45
Ceiling Concealed Duct Type (Low static) ................................................58
Ceiling Concealed Duct Type (High static)................................................68
Outdoor Units.......................................................................................79
Trouble shooting guide ............................................................................113
Exploded View & Replacement Parts List ..............................................183

Service Manual 3
Safety Precautions
Safety Precautions
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 following indications.
■Meanings of symbols used in this manual are as shown below.
WARNING
CAUTION
This symbol indicates the possibility of death or serious injury.
This symbol indicates the possibility of injury or damage to properties only.
Be sure not to do.
Be sure to follow the instruction.
WARNING
■Installation
Have all electric work done by a licensed electri-
cian according to "Electric Facility Engineering
Standard" and "Interior Wire Regulations" and the
instructions given in this manual and always use a
special circuit.
• If the power source capacity is inadequate or electric
work is performed improperly, electric shock and fire
may result.
Ask the dealer or an authorized technician to
install the air conditioner.
• Improper installation by the user may result in water
leakage, electric shock, or fire.
Always ground the product.
• There is risk of fire or electric shock.
Always intstall a dedicated circuit and breaker.
• Improper wiring or installation may cause fire or elec-
tric shock.

4
Safety Precautions
For re-installation of the installed product, always
contact a dealer or an Authorized Service Center.
• There is risk of fire, electric shock, explosion, or injury.
Do not install, remove, or re-install the unit by
yourself (customer).
• There is risk of fire, electric shock, explosion, or injury.
Do not store or use flammable gas or
combustibles near the air conditioner.
• There is risk of fire or failure of product.
Use the correctly rated breaker or fuse.
•Thereisriskoffireorelectricshock.
Prepare for typhoons and other strong winds and
earthquakes and install the unit at the specified
place.
• Improper installation may cause the unit to topple and
result in injury.
Do not install the product on a defective installa-
tion stand.
• It may cause injury, accident, or damage to the prod-
uct.
When installing and moving the air conditioner to
another site, do not charge it with a
differnet refrigerant from the refrigerant specified
on the unit.
• If a differnet refrigerant or air is mixed with the original
refrigerant, the refrigerant cycle may malfunction and
the unit may be gamaged.
Do not reconstruct to change the settings of the
protection devices.
• If the pressure switch, thermal switch, or other protec-
tion device is shorted and operated forcibly, or parts
other than those specified by LGE are used, fire or
explosion may result.
Gasolin

Service Manual 5
Safety Precautions
Ventilate before operating air conditioner when gas
goes out.
• It may cause explosion, fire, and burn.
Securely install the cover of control box and the
panel.
• If the cover and panel are installed securely, dust or
water may enter the outdoor unit and fire or electric
shock may result.
If the air conditioner is installed in a small room, measures must be taken to prevent the
refrigerant concentration from exceeding the safety limit when the refrigerant leaks.
• Consult the dealer regarding the appropriate measures to prevent the safety limit from being exceeded. Should the
refrigerant leak and cause the safety limit to be exceeded, harzards due to lack of oxygen in the room could result.
■Operation
Do not damage or use an unspecified power cord.
• There is risk of fire, electric shock, explosion, or injury.
Use a dedicated outlet for this appliance.
• There is risk of fire or electrical shock.
Be cautious that water could not enter the product.
• There is risk of fire, electric shock, or product damage.
Do not touch the power switch with wet hands.
• There is risk of fire, electric shock, explosion, or injury.

6
Safety Precautions
When the product is soaked (flooded or
submerged), contact an Authorized Service Center.
• There is risk of fire or electric shock.
Be cautious not to touch the sharp edges when
installing.
• It may cause injury.
Take care to ensure that nobody could step on or
fall onto the outdoor unit.
• This could result in personal injury and product dam-
age.
Do not open the inlet grill of the product during
operation. (Do not touch the electrostatic filter, if
the unit is so equipped.)
• There is risk of physical injury, electric shock, or prod-
uct failure.
■Installation
Always check for gas (refrigerant) leakage after
installation or repair of product.
• Low refrigerant levels may cause failure of
product.
Do not install the product where the noise or hot
air from the outdoor unit could damage the neigh-
borhoods.
• It may cause a problem for your neighbors.
Keep level even when installing the product.
• To avoid vibration or water leakage.
Do not install the unit where combustible gas may
leak.
• If the gas leaks and accumulates around the unit, an
explosion may result.
90˚
Gasolin

Service Manual 7
Safety Precautions
Use power cables of sufficient current
carrying capacity and rating.
•Cables that are too small may leak, generate heat, and
cause a fire.
Do not use the product for special purposes, such
as preserving foods, works of art, etc. It is a con-
sumer air conditioner, not a precision refrigeration
system.
•There is risk of damage or loss of property.
Keep the unit away from children. The heat
exchanger is very sharp.
•It can cause the injury, such as cutting the finger. Also
the gamaged fin may result in degradation of capacity.
When installting the unit in a hospital, communica-
tion station, or similar place, provide surfficient
protection against noise.
•The inverter equipment, private power generator, high-
frequency medical equipment, or radio communication
equipment may cause the air conditioner to operate
erroneously, or fail to operate. On the other hand, the
air conditioner may affect such equipment by creating
noise that disturbs medical treatment or image broad-
casting.
Do not install the product where it will be exposed to sea wind (salt spray) directly.
•It may cause corrosion on the product. Corrosion, particularly on the condenser and evaporator fins, could cause
product malfunction or inefficient operation.

8
Safety Precautions
■Operation
Do not use the air conditioner in special
environments.
•Oil, steam, sulfuric smoke, etc. can significantly reduce
the performance of the air conditioner or damage its
parts.
Do not block the inlet or outlet.
•It may cause failure of appliance or accident.
Make the connections securely so that the outside
force of the cable is not applied to the terminals.
•Inadequate connection and fastening may generate
heat and cause a fire.
Be sure the installation area does not deteriorate
with age.
•If the base collapses, the air conditioner could fall with
it, causing property damage, product failure, and per-
sonal injury.
Be very careful about product transportation.
•Only one person should not carry the product if it weighs more than 20 kg.
•Some products use PP bands dor packaging. Do not use any PP bands for
a means of transportation. It is dangerous.
•Do not touch the heat exchanger fins. Doing so may cut your fingers.
•When transporting the Outdoor Unit, suspending it at the specified posi-
tions on the unit base. Also support the Outdoor Unit at four points so that
it cannot slip sideways.
Install and insulate the drain hose to ensure that
water is drained away properly based on the instal-
lation manual.
•A bad connection may cause water leakage.
Do not operate with "System louver" closed.
•It may cause failure of appliance or accident.

Service Manual 9
Safety Precautions
Safely dispose of the packing materials.
•Packing materials, such as mails and other metal or
wooden parts, may cause stabs or other injuries.
•Tear apart and throw away plastic packaging bags so
that children will not play with them. If
children play with a plastic bag which
was not torn apart, they face the risk
of suffocation.
Turn on the power at least 2 hours before starting
operation.(In case of outdoor
temperature 5°C below)
•Starting operation immediately after turning on the
main power switch can result in severe
damage to internal parts. Keep the power switch
turned on during the operational season.
Donottouchanyoftherefrigerantpipingduring
and after operation.
•It can cause a burn or frostbite.
Do not operate the air conditioner with the panels
and guards removed.
•Rotating, hot, or high-voltage parts can cause injuries.
Do not directly turn off the main power switch after
stopping operation.
•Wait at least more than 5 minutes before turning off the
main power switch. Otherwise it may result in water
leakage or other problems.
Auto-addressing should be done in condition of
connecting the power of all indoor and outdoour
units. Auto-addressing should also be done in
case of changing the Indoor Unit board(PCB).
Useafirmstoolorladderwhencleaningormain-
taining the air conditioner.
•Be careful and avoid personal injury.
Do not insert hands or other objects through the
air inlet or outlet while the air conditioner is
plugged in.
•There are sharp and moving parts that could cause
personal injury.

10
Part 1
General Information
1. Model Names ................................................................11
1.1 Indoor Unit .............................................................11
1.2 Outdoor Unit ..........................................................11
2. External Appearance.....................................................12
2.1 Indoor Unit .............................................................12
2.2 Outdoor Unit ..........................................................13
3. Nomenclature.................................................................14
3.1 Indoor Unit .............................................................14
3.2 Outdoor Unit ..........................................................14
4. Outdoor Units information............................................15