LG Multi V User manual

System
SVC MANUAL
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
MODEL: ARUN Series
(1Ø, 208/230V, 60Hz)

- 2 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Air Conditioner Service Manual
TABLE OF CONTENTS
Safety Precautions............................................................................................................................3
Model Names...................................................................................................................................11
External Appearance ......................................................................................................................11
Nomenclature ..................................................................................................................................12
Outdoor Units..................................................................................................................................13
PCB Setting and Test Run..............................................................................................................39
Replacement Procedure.................................................................................................................46
Trouble Shooting Guide .................................................................................................................50

- 3 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
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
electrician 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 or 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
electric shock.

- 4 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
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.
• There is risk of fire or electric shock.
Prepare for strong wind or earthquake and
install the unit at the specified place.
• Improper installation may cause the unit to top-
ple and result in injury.
Do not install the product on a defective
installation stand.
• It may cause injury, accident, or damage to the
product.
When installing and moving the air condition-
er to another site, do not charge it with a
different refrigerant from the refrigerant
specified on the unit.
• If a different refrigerant or air is mixed with the
original refrigerant, the refrigerant cycle may
malfunction and the unit may be damaged.
Do not reconstruct to change the settings of
the protection devices.
• If the pressure switch, thermal switch, or other
protection device is shorted and operated
forcibly, or parts other than those specified by
LGE are used, fire or explosion may result.
Gasolin
R22
R407C
R410A

- 5 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
■Operation
Safety Precautions
Ventilate before operating air conditioner
when gas leaked out.
• It may cause explosion, fire, and burn.
Securely install the cover of control box and
the panel.
• If the cover and panel are not 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 exceed-
ed. Should the refrigerant leak and cause the safety limit to be exceeded, harzards due to lack of oxy-
gen in the room could result.
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 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
CAUTION
■Installation
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
damage.
Do not open the inlet grille of the product
during operation. (Do not touch the electro-
static filter, if the unit is so equipped.)
• There is risk of physical injury, electric shock, or
product failure.
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 neighborhoods.
• 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

- 7 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
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 consumer 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 damaged fin may result in degradation
of capacity.
When installting the unit in a hospital, com-
munication station, or similar place, provide
sufficient protection against noise.
• The inverter equipment, private power generator,
high-frequency medical equipment, or radio com-
munication equipment may cause the air condition-
er 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 broadcasting.
Do not install the product where it is 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 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
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 may not be applied
to the terminals.
• Inadequate connection and fastening may gen-
erate heat and cause a fire.
Be sure the installation area does not deteri-
orate with age.
• If the base collapses, the air conditioner could
fall with it, causing property damage, product
failure, or personal injury.
Install and insulate the drain hose to ensure that water is drained away properly based on the
installation manual.
• A bad connection may cause water leakage.
Be very careful about product transportation.
• Only one person should not carry the product if it weighs more
than 20 kg (44 lbs).
• Some products use PP bands for 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 fin-
gers.
• When transporting the outdoor unit, suspending it at the specified
positions on the unit base. Also support the outdoor unit at four
points so that it cannot slip sideways.

- 9 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Safety Precautions
Safely dispose of the packing materials.
• Packing materials, such as nails and other metal or
wooden parts, may cause stabs or other injuries.
•
Tear apart and throw away plastic packaging bags
so that children may 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 6 hours before
starting operation.
• 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.
Do not touch any of the refrigerant piping
during and after operation.
• It can cause a burn or frostbite.
Do not operate the air conditioner with the
panels or 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 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 PCB.
Use a firm stool or ladder when cleaning or
maintaining 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 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
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. Combination of Outdoor Units .....................................14
4. Nomenclature.................................................................15
4.1 Indoor Unit .............................................................15
4.2 Outdoor Unit ..........................................................15

- 11 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
1. Model Names
Outdoor Unit
Model Names
Heat Pump ARUN
Power Supply 4HP 5HP
1Ø, 208~230V, 60Hz 038GS2 048GS2
2. External Appearance
Outdoor Units
ARUN038GS2
ARUN048GS2
4, 5 HP

- 12 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Nomenclature
3. Nomenclature
3.1 Outdoor Unit
ARU N G048 S2
Generation
Air Discharge Type
S:Side Discharge, H:High Temperature
T:Top Discharge
Electrical Ratings
8: 3Ø, 380 ~ 415V, 50Hz 9: 3Ø, 380V, 60Hz
A: 3Ø, 220V, 50Hz B: 3Ø, 220V, 60Hz
G: 1Ø, 208/230V, 60Hz
L: 3Ø, 380 ~ 415V, 50Hz/3Ø, 380V, 60Hz
Total Cooling Capacity in Btu/h
EX) 38,000 Btu/h ➞ '038' 48,000 Btu/h ➞'048'
Combination of Inverter Type and
Cooling Only or Heat Pump
N: Inverter and H/P V: Inverter and C/O
B: Inverter and Heat Recovery
System with
Outdoor Unit using R410A

- 13 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Part 2
Outdoor Units

- 14 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Functions ........................................................................................15
ARUN Series

- 15 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Function
1. Basic control ..................................................................................................................16
1.1 Normal operation ...........................................................................................................16
1.2 Compressor control........................................................................................................16
1.3 EEV control ....................................................................................................................17
2. Special control ...............................................................................................................18
2.1 Oil return control ............................................................................................................18
2.2 Defrost ...........................................................................................................................20
2.3 Stopping operation.........................................................................................................21
3. Protection control ..........................................................................................................22
3.1 Pressure protection control ............................................................................................22
3.2 Discharge temperature control.......................................................................................24
3.3 Inverter protection control ..............................................................................................24
3.4 Pressure switch..............................................................................................................24
4. Other control ..................................................................................................................25
4.1 Initial Setup ....................................................................................................................25
4.2 Sensor Checking Function.............................................................................................27
4.3 Refrigerant Auto Charging .............................................................................................29
4.4 Refrigerant Checking Function ......................................................................................31
4.5 Pump Down ...................................................................................................................33
4.6 Pump Out.......................................................................................................................35
4.7 Night Silent Operation....................................................................................................37
4.8 Vacuum Mode ................................................................................................................38
4.9 Black Box Function ........................................................................................................39
Function

- 16 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Function
Note : Heating operation is not functional at an outdoor air temperature of 27°C(81°F) or more.
1.2 Compressor control
Fuzzy control : Maintain evaporating temperature(Te) to be constant on cooling mode and condensing tem-
perature(Tc) on heating mode by Fuzzy control to ensure the stable system performance.
(Tc:47 ~51°C(117~124°F), Te:2 ~ 5°C(36~41°F)
(1) Cooling mode
Te can be set by initial DIP switch setting. (Standard, Long pipe)
(2) Heating mode
Tc can be set by initial DIP switch setting. (Standard, Long pipe)
Note: By setting DIP switch, Te and Tc are decided simultaneously.
1.1 Normal operation
1. Basic Control
Compressor
Fan
Main EEV
4 way valve
Subcooling
Indoor Unit
EEV
EEV
Fuzzy control
Fuzzy control
Full open
OFF
Fuzzy control
Superheat fuzzy
control
Fuzzy control
Subcooling fuzzy control
Fuzzy control
Fuzzy control
Fuzzy control
ON
Cooling operation Heating operationActuator
Stop
Stop
Close
OFF
1 hour after stop & outdoor temp.
< 27˚C(81˚F)
Close
Before 10 min. : Min. pulse
After 10 min. : Max. pulse
Stop state
Fuzzy Control
Stop(0Hz)
Min. frequency
Fuzzy control start
Target
Inverter linear control as cooling and heating load increasing
System Capacity
Cooling and heating load
(Linear Control)(Linear Control)(Linear Control)
InverterInverter
CompressorCompressor
Inverter
Compressor

- 17 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
1.3 EEV control
(1) EEV control
EEV operates with fuzzy control rules to keep the degree of super Heat(Superheat) (about 3°C(6°F)at the
evaporator outlet stable during heating mode
The degree of Superheat = Tsuction - Tevaporation
Tsuction : temperature at suction pipe sensor(°C/
°F )
Tevaporation : evaporation temperature equivalent to low pressure(°C/ °F )
(2) Subcooling EEV control(about 15°C( °F))
Subcooling EEV works with fuzzy rules to keep the degree of Subcool at the outlet of subcooler during
cooling mode
The degree of Subcool = Tsubcool_out - Tevaporation
Tsubcool_out : temperatrue at outlet of subcooler(°C/°F)
Tevaporation : evaporation temperature equivalent to low pressure(°C/°F)
Function

- 18 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
2.1 Oil return control
2.1.1 Oil return control on cooling mode
Oil return operation recovers oil amount in compressor by collecting oil accumulated in pipe.
Each cycle component operates as following table during oil return operation.
■Oil return operation time : 6 min. for running step
■Starting condition:every 6 hours operate
■Oil return process ends if compressor protection control starts
Normal control
OFF
100 pulse
Max. pulse
Normal control
40Hz
Ending
Normal control
OFF
Min. pulse
Max. pulse
Normal control
Setting Value
Running
Normal control
OFF
Min. pulse
Max. pulse
Normal control
30Hz
Starting
Hot gas bypass valve
4way valve
Subcooling EEV
Main EEV
Fan
Inverter compressor
Component
OFF
Min. pulse
Normal control
Normal control
Ending
ON
1200 pulse
1200 pulse
Normal control
Running
OFF
Min. pulse
Normal control
Normal control
Starting
Oil return signal
Thermo off unit EEV
Thermo on unit EEV
Fan
Component
Outdoor Unit
Indoor Unit
2. Special Control
Function

- 19 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
2.1.2 Oil return control on heating mode
■Oil return operation time : 3 min. for running step
■ Starting condition:same as cooling mode
■ Oil return process ends if compressor protection control starts
Outdoor Unit
Indoor Unit
OFF
Min. pulse
Normal control
Normal control
Ending
ON
1200 pulse
1200 pulse
OFF
Running
OFF
Min. pulse
Normal control
Normal control
Starting
Hot gas bypass valve
4way valve
Subcooling EEV
Main EEV
Fan
Inverter compressor
Component
ON
ON
Normal control
Normal control
Normal control
30Hz
Starting
ON
Normal control
Max. pulse
Setting Value
Running
ON
ON
200 pulse
Normal control
Normal control
30Hz
Ending
Oil return signal
Thermo off unit EEV
Thermo on unit EEV
Fan
Component
0Hz →Normal control →700 RPM
ON →OFF → ON
Function

- 20 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes LGE Internal Use Only
Outdoor Unit
Indoor Unit
OFF
Min. pulse
Normal control
Normal control
Ending
ON
1200 pulse
1200 pulse
OFF
Running
OFF
Min. pulse
Normal control
Normal control
Starting
Hot gas bypass valve
4way valve
Subcooling EEV
Main EEV
Fan
Inverter compressor
Component
ON
ON
Normal control
Normal control
Normal control
30Hz
Starting
ON
Normal control
Max. pulse
Setting Value
Running
ON
ON
200 pulse
Normal control
Normal control
30Hz
Ending
Oil return signal
Thermo off unit EEV
Thermo on unit EEV
Fan
Component
0Hz →Normal control →700 RPM
ON →OFF → ON
Function
2.2 Defrost
Defrost operation eliminates ice attached on heat exchanger, recovering performance of heat exchanger.
Each cycle component operates as following table during defrost operation.
■Ending condition
1) All heat exchanger pipe temperature are above 15°C(59°F)(U3) for 30 sec.
2) The running time of defrost operation is over 30% of the total heating time
3) If compressor protection control starts by high discharge temperature of compressor etc.