LG MULTI V ARUN072BTE4 User manual

Service Manual
Heat Pump and Heat Recovery
Variable Refrigerant Flow Outdoor Units
6.0 to 42.0 Tons
SM-MultiV-IV-Air-Outdoor-Units-4-15
Heat Pump
208 / 230V, 60Hz, 3-phase
and
460V, 60Hz, 3-phase
ARUN072BTE4 / ARUN072DTE4
ARUN096BTE4 / ARUN096DTE4
ARUN121BTE4 / ARUN121DTE4
ARUN144BTE4 / ARUN144DTE4
ARUN168BTE4 / ARUN168DTE4
ARUN192BTE4 / ARUN192DTE4
ARUN216BTE4 / ARUN216DTE4
ARUN240BTE4 / ARUN240DTE4
ARUN264BTE4 / ARUN264DTE4
ARUN288BTE4/ ARUN288DTE4
ARUN313BTE4 / ARUN313DTE4
ARUN337BTE4 / ARUN337DTE4
ARUN312BTE4 / ARUN312DTE4
ARUN336BTE4 / ARUN336DTE4
ARUN360BTE4 / ARUN360DTE4
ARUN384BTE4 / ARUN384DTE4
ARUN408BTE4 / ARUN408DTE4
ARUN432BTE4 / ARUN432DTE4
ARUN456BTE4 / ARUN456DTE4
ARUN480BTE4 / ARUN480DTE4
ARUN504BTE4 / ARUN504DTE4
Heat Recovery
208 / 230V, 60Hz, 3-phase
and
460V, 60Hz, 3-phase
ARUB072BTE4 / ARUB072DTE4
ARUB096BTE4 / ARUB096DTE4
ARUB121BTE4 / ARUB121DTE4
ARUB144BTE4 / ARUB144DTE4
ARUB168BTE4 / ARUB168DTE4
ARUB192BTE4 / ARUB192DTE4
ARUB216BTE4 / ARUB216DTE4
ARUB240BTE4 / ARUB240DTE4
ARUB264BTE4 / ARUB264DTE4
ARUB288BTE4 / ARUB288DTE4
ARUB313BTE4 / ARUB313DTE4
ARUB337BTE4 / ARUB337DTE4
ARUB312BTE4 / ARUB312DTE4
ARUB336BTE4 / ARUB336DTE4
ARUB360BTE4 / ARUB360DTE4
ARUB384BTE4 / ARUB384DTE4
ARUB408BTE4 / ARUB408DTE4
ARUB432BTE4 / ARUB432DTE4
ARUB456BTE4 / ARUB456DTE4
ARUB480BTE4 / ARUB480DTE4
ARUB504BTE4 / ARUB504DTE4

Follow the instructions in this manual to prevent product malfunction, property damage, injury, or death to users or other people. Incorrect
operation due to ignoring any instructions can cause harm to personnel, or damage to property or equipment.
Do not throw away, destroy, or lose this manual.
Please read carefully and store in a safe place for future reference.
Content familiarity required for proper installation and safety of personnel and property.
For more technical materials such as submittals, engineering
databooks, installation manuals, and catalogs, visit www.lghvac.com.
For continual product development, LG Electronics U.S.A., Inc., reserves the right to change specifications without notice.
©LG Electronics U.S.A., Inc.
This document, as well as all reports, illustrations, data, information, and other materials are the property of LG Electronics U.S.A., Inc.
PROPRIETARY DATA NOTICE
This document, as well as all reports, illustrations, data, information, and
other materials herein are the property of LG Electronics U.S.A., Inc., and
are disclosed by LG Electronics U.S.A., Inc., only in confidence.
This document is for design purposes only.
Freight Damage and Unit Replacements .................................................................................................. Your LG Manufacturer Representative
Missing Parts............................................................................................................................................. Your LG Manufacturer Representative
Received Wrong Water Source Unit Model............................................................................................... Your LG Manufacturer Representative
Installation, Startup, and Commissioning Technical Assistance................................................................ 1-888-865-3026

Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp. 3
TABLE OF CONTENTS
Safety Precautions ................................................................................ 4
Nomenclature......................................................................................... 8
Outdoor Unit Functions ................................................................... 9-40
Basic Controls ................................................................................ 9-10
Normal Operation / Compressor Control ......................................... 9
Master-Slave Unit EEVs ................................................................ 10
Special Controls ....................................................................... 11-13
Oil Return Control...........................................................................11
Defrost Control / Partial Defrost Control ........................................ 12
Stop Operation .............................................................................. 13
Protection Controls....................................................................... 14-16
Pressure Protection Control .......................................................... 14
Discharge Temperature Control / Inverter Protection Control 15
Phase Detection / Pressure Switch ............................................... 16
Other Controls .............................................................................. 17-40
Initial Setup............................................................................... 17-19
Emergency Operation............................................................... 20-21
Refrigerant Auto Charge........................................................... 22-23
Initial Test Run (ITR) (Cooling) ...................................................... 25
Initial Test Run (ITR) (Heating) ................................................. 26-27
Fault Detection Diagnosis (FDD) Code ......................................... 27
Multi V ITR Result Report ........................................................ 28-29
Pump Down .............................................................................. 30-31
Pump Out ................................................................................. 32-35
Auto Back Up Function (Inverter Compressor).............................. 36
Night Low Sound Function ............................................................ 37
Vacuum Mode / Static Pressure Compensation Mode .................. 38
Mode Control ................................................................................. 39
Cycle Data View ............................................................................ 40
Heat Recovery Units....................................................................... 41-48
Parts Functions.................................................................................. 41
Dimensional Diagrams ................................................................. 42-44
Refrigerant Circuit Diagram............................................................... 45
Wiring Diagram.................................................................................. 46
Functions...................................................................................... 47-48
PCB Settings and Test Run ........................................................... 49-62
Heat Recovery Unit Settings ........................................................ 49-53
Indoor Unit Addressing ................................................................. 54-55
Indoor and Heat Recovery Unit Addressing Flow Chart.................... 56
Pipe Detection .............................................................................. 57-61
Troubleshooting ........................................................................... 63-149
Test Run ............................................................................................ 63
Troubleshooting Main Component Errors..................................... 64-76
Checking the Compressor................................................................. 66
Checking the Outdoor Unit Fan Motor............................................... 67
Checking the Electronic Expansion Valves................................... 68-70
Checking the Phase Bridge Diode..................................................... 71
Checking the Inverter IPM / IGBT...................................................... 72
Checking the Fan IPM....................................................................... 73
Checking the High / Low Pressure Sensors ..................................... 74
Checking the Solenoid Valves ........................................................... 75
Four-Way Reverse Valve................................................................... 75
Temperature Sensor .......................................................................... 76
Electrical Capacitor and Resistor for Voltage Distributor................... 76
Error Code Tables......................................................................... 77-83
Service Troubleshooting ............................................................. 84-149

Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp.
4
MULTI V IV Outdoor Unit Service Manual
SAFETY PRECAUTIONS
The instructions below must be followed to prevent product malfunction, property damage, injury or death to the user or other people. Incor-
rect operation due to ignoring any instructions will cause harm or damage. The level of seriousness is classified by the symbols described
below.
TABLE OF SYMBOLS
This symbol indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.
This symbol indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.
This symbol indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury.
This symbol indicates situations that may result in equipment or property damage accidents only.
This symbol indicates an action should not be completed.
DANGER
CAUTION
Do not install, remove, or re-install the unit by yourself
(end user). Ask the dealer or an authorized technician to
install the unit.
Improper installation by the user may result in re, explosion, electric
shock, physical injury or death.
For replacement of an installed unit, always contact an LG
trained service provider.
There is risk of re, electric shock, explosion, and physical injury or
death.
Wear protective gloves when handling equipment. Sharp
edges may cause personal injury.
Do not change the settings of the protection devices.
If the pressure switch, thermal switch, or other protection device is
shorted and forced to operate improperly, or parts other than those
specied by LG are used, there is risk of re, electric shock, explosion,
and physical injury or death.
Replace all control box and panel covers.
If cover panels are not installed securely, dust, water and animals may
enter the outdoor unit, causing re, electric shock, and physical injury or
death.
Always check for system refrigerant leaks after the unit has
been installed or serviced.
Exposure to high concentration levels of refrigerant gas may lead to
illness or death.
If the air conditioner is installed in a small space, take
measures to prevent the refrigerant concentration from
exceeding safety limits in the event of a refrigerant leak.
Consult the latest edition of ASHRAE (American Society of Heating,
Refrigerating, and Air Conditioning Engineers) Standard 15. If the
refrigerant leaks and safety limits are exceeded, it could result in person-
al injuries or death from oxygen depletion.
The heat recovery unit must be installed indoors; do not
install the heat recovery unit in a highly humid environment.
There is risk of physical injury or death due to electric shock.
Periodically check that the outdoor frame is not damaged.
There is a risk of explosion, physical injury, or death.
Dispose the packing materials safely.
• Packing materials, such as nails and other metal or wooden parts,
may cause puncture wounds or other injuries.
• Tear apart and throw away plastic packaging bags so that children
may not play with them and risk suffocation and death.
Install the unit considering the potential for strong winds or
earthquakes.
Improper installation may cause the unit to fall over, resulting in physical
injury or death.
Install the unit in a safe location where nobody can step on
or fall onto it. Do not install the unit on a defective stand.
It may result in an accident that causes physical injury or death.
INSTALLATION
Do not store or use ammable gas or combustibles near the unit.
There is risk of re, explosion, and physical injury or death.
DANGER

Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp. 5
General Information
SAFETY PRECAUTIONS
CAUTION
Be very careful when transporting the product. There is a risk
of the product falling and causing physical injury.
• Use appropriate moving equipment to transport each frame; ensure
the equipment is capable of supporting the weights listed above.
• Some products use polypropylene bands for packaging. Do not use
polypropylene bands to lift the unit.
• Suspend the outdoor unit from the base at specified positions.
Support the outdoor unit a minimum of four points to avoid slippage
from rigging apparatus.
INSTALLATION, CONTINUED
Do not install the product where it is exposed directly to
ocean winds.
Sea salt in the air may cause the product to corrode. Corrosion,
particularly on the condenser and evaporator ns, could cause product
malfunction or inefcient operation.
When installing the outdoor unit in a low-lying area, or a lo-
cation that is not level, use a raised concrete pad or concrete
blocks to provide a solid, level foundation.
This prevents water damage and abnormal vibration.
Properly insulate all cold surfaces to prevent “sweating.”
Cold surfaces such as uninsulated piping can generate condensate that
may drip and cause a slippery surface condition and / or water damage
to walls.
When installing the unit in a hospital, mechanical room, or
similar electromagnetic eld (EMF) sensitive environment,
provide sufcient protection against electrical noise.
Inverter equipment, power generators, high-frequency medical equip-
ment or radio communication equipment may cause the air conditioner
to operate improperly. The unit may also affect such equipment by
creating electrical noise that disturbs medical treatment or image broad-
casting.
Always check for system refrigerant leaks after the unit has
been installed or serviced.
Low refrigerant levels may cause product failure.
The heat recovery box must be installed indoors; do not
install the heat recovery box in a highly humid environment.
There is risk of product failure and property damage.
Do not make refrigerant substitutions. Use R410A only.
If a different refrigerant is used, or air mixes with original refrigerant, the
unit will malfunction and be damaged.
Do not use the product for mission critical or special purpose
applications such as preserving foods, works of art, or other
precision air conditioning applications. The equipment is
designed to provide comfort cooling and heating.
There is risk of property damage.
Keep the unit upright during installation to avoid vibration or
water leakage.
When connecting refrigerant tubing, remember to allow for
pipe expansion.
Improper piping may cause refrigerant leaks and system malfunction.
Do not install the outdoor unit or heat recovery unit in a
noise-sensitive area.
Take appropriate actions at the end of HVAC equipment life
to recover, recycle, reclaim or destroy R410A refrigerant
according to applicable U.S. Environmental Protection
Agency (EPA) rules.
Periodically check that the outdoor frame is not damaged.
There is a risk of equipment damage.
Install the unit in a safe location where nobody can step on
or fall onto it. Do not install the unit on a defective stand.
There is a risk of unit and property damage.
Install the drain hose to ensure adequate drainage.
There is a risk of water leakage and property damage.
Do not store or use ammable gas / combustibles near the unit.
There is a risk of product failure.
Properly insulate all cold surfaces to prevent “sweating.”
Cold surfaces such as uninsulated piping can generate condensate
that could drip, causing a slippery surface that creates a risk of slipping,
falling, and personal injury.

Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp.
6
MULTI V IV Outdoor Unit Service Manual
SAFETY PRECAUTIONS
Do not supply power to the unit until all electrical wiring,
controls wiring, piping, installation, and refrigerant system
evacuation are completed.
The information contained in this manual is intended for use
by an industry-qualied, experienced, certied electrician
familiar with the U.S. National Electric Code (NEC) who is
equipped with the proper tools and test instruments.
Failure to carefully read and follow all instructions in this manual can
result in equipment malfunction, property damage, personal injury or
death.
All electric work must be performed by a licensed electrician
and conform to local building codes or, in the absence of
local codes, with the National Electrical Code, and the
instructions given in this manual.
If the power source capacity is inadequate or the electric work is not
performed properly, it may result in re, electric shock, physical injury or
death.
Refer to local, state, and federal codes, and use power wires
of sufcient current capacity and rating.
Wires that are too small may generate heat and cause a re.
Secure all eld wiring connections with appropriate wire
strain relief.
Improperly securing wires will create undue stress on equipment power
lugs. Inadequate connections may generate heat, cause a re and
physical injury or death.
Properly tighten all power lugs.
Loose wiring may overheat at connection points, causing a re, physical
injury or death.
Do not change the settings of the protection devices.
If the pressure switch, thermal switch, or other protection devices are
bypassed or forced to work improperly, or parts other than those
specied by LG are used, there is risk of re, electric shock, explosion,
and physical injury or death.
WIRING
DANGER
High voltage electricity is required to operate this system.
Adhere to the NEC code and these instructions when wiring.
Improper connections and inadequate grounding can cause accidental
injury or death.
Always ground the unit following local, state, and NEC codes.
There is risk of re, electric shock, and physical injury or death.
Turn the power off at the nearest disconnect before servicing
the equipment.
Electrical shock can cause physical injury or death.
Properly size all circuit breakers or fuses.
There is risk of re, electric shock, explosion, physical injury or death.

Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp. 7
General Information
SAFETY PRECAUTIONS
OPERATION
DANGER
To avoid physical injury, use caution when cleaning or
servicing the air conditioner.
CAUTION
Do not allow water, dirt, or animals to enter the unit.
There is risk of re, electric shock, physical injury or death.
Do not touch the refrigerant piping during or after operation.
It can cause burns or frostbite.
Do not operate the unit with the panel(s) or protective cov-
er(s) removed; keep ngers and clothing away from
moving parts.
The rotating, hot, cold, and high-voltage parts of the unit can cause
physical injury or death.
Do not provide power to or operate the unit if it is ooded or
submerged.
There is risk of re, electric shock, physical injury or death.
Use a dedicated breaker for this product.
There is risk of re, electric shock, physical injury or death.
Do not operate the disconnect switch with wet hands.
There is risk of re, electric shock, physical injury or death.
Periodically verify the equipment mounts have not
deteriorated.
If the base collapses, the unit could fall and cause physical injury or
death.
Use inert (nitrogen) gas when performing leak tests or air
purges. Do not use compressed air, oxygen, or ammable
gases.
Using these substances may cause re, explosion, and physical injury
or death.
If refrigerant leaks out, ventilate the area before operating the
unit.
If the unit is mounted in an ecnlosed, low-lying, or poorly ventilated area,
and the the system develops a refrigerant leak, it may cause a re,
electric shock, explosion, physical injury or death.
Clean up the site after servicing is nished, and check that
no metal scraps, screws, or bits of wiring have been left
inside or surrounding the unit.
Do not use the product for mission critical or special purpose
applications such as preserving foods, works of art, or other
precision air conditioning applications. The equipment is
designed to provide comfort cooling and heating.
Oil, steam, sulfuric smoke, etc., can signicantly reduce the performance
of the unit, or damage its parts.
Turn on the power at least six (6) hours before operation
begins.
Starting operation immediately after turning on the main power switch
can result in severe damage to the compressor(s). Keep the power
switch on during the operational season.
Do not turn off the main power switch after operation has
been stopped.
Wait at least ve (5) minutes before turning off the main power
switch, otherwise it may result in product malfunction.
Do not block the inlet or outlet.
Unit may malfunction.
Auto-addressing should be performed after connecting the
power of all indoor and outdoor units.
Auto-addressing should also be performed after servicing an indoor unit.
Do not allow water, dirt, or animals to enter the unit.
There is risk of unit failure.
Do not operate the unit with the panel(s) or protective cov-
er(s) removed; keep ngers and clothing away from
moving parts.
Non-secured covers can result in malfunction due to dust or water in the
service panel.
Periodically verify the equipment mounts have not
deteriorated.
If the base collapses, the unit could fall and cause property damage or
product failure.

Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp.
8
MULTI V IV Outdoor Unit Service Manual
Outdoor Units (ODU)
Heat Recovery Units (HRU)
PRHR 02 2A
Series Number
2A = Series Number
Number of Connected
Ports
02 = 2 Ports
03 = 3 Ports
04 = 4 Ports
Family
PRHR = Multi V Heat Recovery (HR) unit using R410A
refrigerant
UNIT NOMENCLATURE
Outdoor and Heat Recovery Control Units
ARU N072 B T 4
Generation
4 = Fourth
Airflow Configuration
T = Top Discharge
Electrical Ratings
B = 208–230V/60Hz/3Ph
D = 460V/60Hz/3Ph
Nominal Capacity
(Nominal cooling capacity in Btu/h)
Type
N = Inverter Heat Pump
B = Inverter Heat Recovery
Family
ARU = Multi V Outdoor Unit (Refrigerant R410A)
E
Efficiency
E = High Efficiency
072 = 72,000
096 = 96,000
121 = 121,000
144 = 144,000
168 = 168,000
192 = 192,000
216 = 216,000
240 = 240,000
264 = 264,000
288 = 288,000
312/313 = 312,000
336/337 = 336,000
360 = 360,000
384 = 384,000
408 = 408,000
432 = 432,000
456 = 456,000
480 = 480,000
504 = 504,000

Due to our policy of continuous product innovation, some specications may change without notication.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp. 9
Outdoor Unit Functions
BASIC CONTROLS
Normal Operation / Compressor Control
Table 1: Normal Operation Functions.
Component Cooling Operation Heating Operation System Not in Operation
Compressor Fuzzy Logic Fuzzy Logic Stop
Fan Fuzzy Logic Fuzzy Logic Stop
Main EEV Higher: Minimum Pulse
Lower: Fully Open Fuzzy Logic Minimum Pulse
Subcooling EEV Fuzzy Logic
• Normal: Vapor injection
• Avoiding control of high discharge
temperature
Minimum Pulse
Indoor Unit EEV Superheat Fuzzy Logic Subcooling Fuzzy Logic Minimum Pulse
Heating mode does not operate when outside air temperature is >81°F and head pressure is >514 psi.
Normal Operation
Compressor Control
Fuzzy logic helps ensure stable system performance by maintaining evaporating temperatures (Te) in cooling mode, and condensing tem-
peratures (Tc) in heating mode. Both cooling and heating modes can be determined at various steps in the installation mode.
• Te: 36~41°F
• Tc: 117~124°F
Te and Tc can be simultaneously determined by setting DIP switches.
Fuzzy Logic
Stop(0 Hz)
Min. frequency
Fuzzy Logic start
Target
Inverter linear control as cooling and heating load increases
System Capacity
Cooling and heating load
(Linear Control)(Linear Control)
Inverter
Comp 2
Inverter
Comp 1
Inverter
Comp 2
Inverter
Comp 3
Inverter
Comp 1
Inverter
Comp 2
Inverter
Comp 3
Inverter
Comp 4
Inverter
Comp 1
Figure 1: Fuzzy Logic Diagram. Figure 2: Inverter Linear Control Chart.

Due to our policy of continuous product innovation, some specications may change without notication.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp.
10
MULTI V IV Outdoor Unit Service Manual
Main EEV Control
Main EEV operates with fuzzy logic to keep the degree of superheat (about 37°F) at the evaporator outlet stable during heating mode.
Degree of Superheat = Tsuction - Tevaporation
where,
• Tsuction = Temperature measured at the suction pipe sensor (°F).
• Tevaporation = Evaporation temperature equivalent to low pressure (°F).
Master and Slave Outdoor Unit EEV Control
Subcooling EEV Control
Subcooling EEV operates with fuzzy logic to keep the degree of subcool (about 59°F) at the subcooler outlet stable during cooling mode.
Degree of Subcool = Tcondensation - Tliquid
where,
• Tliquid = Temperature at the outlet of the subcooler (°F).
• Tcondensation = Condensation temperature equivalent to high pressure (°F).
Master-Slave Unit EEVs
Avoiding Excessively High Discharge Temperatures
After the main EEV opens to a predetermined amount (R410A: 800 pulses), and the discharge temperature is above 185°F (or 85°C) during
heating mode, subcooling EEV control may operate to maintain compressor superheat.
Vapor Injection Flow Rate Control During Heating Mode
The degree of Superheat (VI_SH) = Subcooler out (°F) – Subcooler in (°F)
where
• Td ≤ 176°F : VI_SH = 37°F
• 176°F < Td ≤ 194°F : VI_SH = -2 × Td/10 +19
• 194°F < Td : VI_SH = 34°F
BASIC CONTROLS

Due to our policy of continuous product innovation, some specications may change without notication.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp. 11
Outdoor Unit Functions
SPECIAL CONTROLS
Oil Return Control
Oil Return Control
Oil return operation recovers any oil that has accumulated in the piping and returns it to the compressor. Each component operates as shown
in the tables below during oil return.
Table 2: Outdoor Unit Oil Return Control in Cooling Mode.
Component Start During Oil Return Operation Stop
Inverter Compressor 30Hz Set Value 30Hz
Fan Normal Control Normal Control Normal Control
Main EEV Upper: Minimum Pulse
Lower: Maximum Pulse
Upper: Minimum Pulse
Lower: Maximum Pulse
Upper: Normal Control
Lower: Normal Control
Subcooling EEV Minimum Pulse 20 Pulse 80 Pulse
Four-Way Valve Off Off Off
Table 3: Indoor Unit Oil Return Control in Cooling Mode.
Component Start During Oil Return Operation Stop
Fan Normal Control Off Normal Control
Thermo On Unit EEV Normal Control Normal control Normal Control
Thermo Off Unit EEV 40 Pulse 400 Pulse 40 Pulse
Oil Return Signal Off On Off
• Start: Oil return operation begins when the oil sensor measures low oil levels.
• Oil Return Operation will run for three (3) minutes.
• Stop: Oil Return Operation will end if / when compressor protection control starts.
Oil Return Control in Cooling Mode
Table 4: Outdoor Unit Oil Return Control in Heating Mode.
Component Start During Oil Return Operation Stop
Inverter Compressor 30Hz Set Value 40Hz
Fan Normal Control Normal Control Normal Control
Main EEV Upper: Minimum Pulse
Lower: Maximum Pulse
Upper: Minimum Pulse
Lower: Maximum Pulse
Upper: Normal Control
Lower: Normal Control
Subcooling EEV Minimum Pulse 20 Pulse 80 Pulse
Four-Way Valve On Off On
Oil Return Control in Heating Mode
Table 5: Indoor Unit Oil Return Control in Heating Mode.
Component Start During Oil Return Operation Stop
Fan Normal Control Off Normal Control
Thermo On Unit EEV Normal Control 400~800 Pulse Normal Control
Thermo Off Unit EEV 80~130 Pulse 400~800 Pulse 80~130 Pulse
• Start: Oil Return Operation begins when the oil sensor measures low oil levels.
• Oil Return Operation will run for three (3) minutes.
• Stop: Oil Return Operation will end if / when compressor protection control starts.

Due to our policy of continuous product innovation, some specications may change without notication.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp.
12
MULTI V IV Outdoor Unit Service Manual
SPECIAL CONTROLS
Defrost Control / Partial Defrost Control
Defrost Control
Defrost Control eliminates ice that has accumulated on the heat exchanger, recovering its performance. Each component operates as shown
in the tables below during defrost.
Component Start During Defrost Control Operation Stop
Inverter Compressor 30Hz Set Value 40Hz
Fan Stop High Pressure control Normal Control
Main EEV Normal Control Maximum Pulse Normal Control
Subcooling EEV Normal Control Minimum Pulse Normal Control
Four-Way Valve On to Off Off On
Table 6: Outdoor Unit Defrost Control.
Table 7: Indoor Unit Defrost Control.
Component Start During Defrost Control Operation Stop
Fan Off Off Off
Thermo On Unit EEV Normal Control 400~800 Pulse Normal Control
Defrost Control Stop Operation
1. All heat exchanger pipe temperatures are above set temperatures for thirty (30) seconds.
2. Defrost Control Operation will run for >30% of the total heating time.
3. Defrost Control Operation will stop if / when compressor protection control starts (if a high discharge temperature at the compressor is
detected).
Partial Defrost
The heat exchanger in the outdoor unit(s) is divided into a top part and bottom part for partial defrost operation. Partial defrost operation
permits the system to defrost the parts of the heat exchanger separately so heating mode can operate continuously. Each component
operates as shown on the below table during partial defrost.
Component Start During Defrost Control Operation Stop
Inverter Compressor Normal Control Set Value Normal Control
Fan Normal Control Low Pressure control Normal Control
Main EEV Normal Control Normal Control Normal Control
Subcooling EEV Normal Control Normal Control Normal Control
Four-Way Valve On On On
Component Start During Defrost Control Operation Stop
Fan ON (Setting) ON (Low) ON (Setting)
Thermo On Unit EEV Normal Control Normal Control Normal Control
Table 8: Outdoor Unit Partial Defrost Control.
Table 9: Indoor Unit Partial Defrost Control.
Partial Defrost Control Stop Operation
1. Partial Defrost Control Operation will run for a maximum of twelve (12) minutes.
2. Partial Defrost Control Operation will stop for the top part of the heat exchanger when the temperature rises higher than the set
temperature.
3. Partial Defrost Control Operation will stop for the bottom top part of the heat exchanger when the temperature rises above the set
temperature.

Due to our policy of continuous product innovation, some specications may change without notication.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp. 13
Outdoor Unit Functions
SPECIAL CONTROLS
Stop Operation Control
Stop Operation
Component Stop Operation Notes
Inverter Compressor Off -
Fan Stop -
Main EEV 32 Pulse -
Subcooling EEV 16 Pulse Stop (Minimum Pulse)
Four-Way Valve Off -
Stop Operation Control in Cooling Mode
Stop Operation Control in Heating Mode
Component Stop Operation Notes
Inverter Compressor Off -
Fan Stop -
Main EEV 32 Pulse -
Subcooling EEV 16 Pulse Stop (Minimum Pulse)
Four-Way Valve Off When air temperature is >30°C (86°F)
Table 10: Stop Operation Control in Cooling Mode.
Table 11: Stop Operation Control in Heating Mode.
Oil Equalizing Control
Oil equalizing control prevents oil imbalance between the inverter compressors. If the oil level sensors detect different oil levels between the
compressors, then the oil equalizing EEV will open for five (5) minutes.

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14
MULTI V IV Outdoor Unit Service Manual
PROTECTION CONTROLS
Pressure Protection Control
Pressure Protection Control
Pressure Control in Cooling Mode
Pressure Range Compressor Fan
Pd ≥ 580 psi
548 psi
519 psi
Stop Stop
Pd > 548 psi -15 Hz / 10 seconds +100 RPM / 10 seconds
Pd ≥ 510 psi Frequency Hold* +100 RPM / 10 seconds
Pd ≥ 505 psi +2 Hz or less / 10 seconds +100 RPM / 10 seconds
Pd < 505 psi Normal Control
Table 12: High Pressure Control in Cooling Mode.
Pressure Range Compressor Fan
Ps ≤ 14 psi, One (1) minute After Operation Stop Stop
Ps ≤ 118 psi, One (1) minute Before Operation -15Hz / 10 seconds -100 RPM / 10 seconds
Table 13: Low Pressure Control in Cooling Mode.
* Frequency Hold = Frequency (or RPM) is not increasing (can decrease).
Pressure Control in Heating Mode
Pressure Range Compressor Fan
Pd ≥ 581 psi Stop Stop
Pd > 495 psi -15 Hz / 10 seconds -50 RPM / 10 seconds
Table 14: High Pressure Control in Heating Mode.
Table 15: Low Pressure Control in Heating Mode.
Pressure Range Compressor Fan
Ps ≤ 14 psi Stop Stop
Ps ≤ 18 psi -15 Hz / 10 seconds +100 RPM / 10 seconds
Ps ≤ 20 psi Frequency Hold* +100 RPM / 10 seconds
Ps ≤ 28 psi +2 Hz or less / 10 seconds +100 RPM / 10 seconds
Ps ≥ 28 psi Normal Control Normal Control
* Frequency Hold = Frequency (or RPM) is not increasing (can decrease).

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Outdoor Unit Functions
PROTECTION CONTROLS
Discharge Temperature Control / Inverter Protection Control
Temperature Range Compressor Subcooling EEV Indoor Unit EEV
Tdis > 230°F Off SC, SH Decrease Control SH Decrease Control
Tdis > 226.4°F -5 Hz / 10 seconds SC, SH Decrease Control SH Decrease Control
Tdis ≥ 221°F Frequency Hold* SC, SH Decrease Control SH Decrease Control
Tdis ≤ 212°F Normal Control SC, SH Decrease Control SH Decrease Control
Tdis > 212°F Normal Control SC, SH Decrease Control SH Decrease Control
Discharge Temperature Control
Table 16: Outdoor Unit Discharge Temperature Control.
* Frequency Hold = Frequency (or RPM) is not increasing (can decrease).
Tdis = Temperature Discharge.
SC = Subcooling.
SH = Superheating.
Inverter Protection Control
Table 17: Inverter Protection Control in Cooling Mode.
System Voltage
Type
Normal System Operation Frequency Will Drop System Will Stop Operation
4.8 HP 6.8 HP 4.8 HP 6.8 HP 4.8 HP 6.8 HP
Heat Pump Outdoor Units
AC Input Current 208-230V less than 19A less than 28A more than 19A more than 28A more than 24A more than 32A
460V less than 22A less than 30A more than 22A more than 30A more than 22A more than 32A
Compressor Current 208-230V less than 24A less than 35A more than 24A more than 35A more than 30A more than 41A
460V less than 24A less than 35A more than 24A more than 35A more than 30A more than 41A
Heat Recovery Outdoor Units
AC Input Current 208-230V less than 19A less than 28A more than ≥19A more than 28A more than 24A more than 32A
460V less than 22A less than 30A more than ≤22A more than 30A more than 22A more than 32A
Compressor Current 208-230V less than 24A less than 35A more than ≥24A more than 35A more than 30A more than 41A
460V less than 24A less than 35A more than ≤24A more than 35A more than 30A more than 41A
System Voltage
Type
Normal System Operation Frequency Will Drop System Will Stop Operation
4.8 HP 6.8 HP 4.8 HP 6.8 HP 4.8 HP 6.8 HP
Heat Pump Outdoor Units
AC Input Current 208-230V less than 19A less than 28A more than 19A more than 28A more than 24A more than 32A
460V less than 22A less than 30A more than 22A more than 30A more than 22A more than 32A
Compressor Current 208-230V less than 24A less than 35A more than 24A more than 35A more than 30A more than 41A
460V less than 26A less than 35A more than 26A more than 35A more than 30A more than 41A
Heat Recovery Outdoor Units
AC Input Current 208-230V less than ≤19A less than 28A more than 19A more than 28A more than 24A more than 32A
460V less than ≤22A less than 30A more than 22A more than 30A more than 22A more than 32A
Compressor Current 208-230V less than ≤24A less than 35A more than 24A more than 35A more than 30A more than 41A
460V less than ≤26A less than 35A more than 26A more than 35A more than 30A more than 41A
Table 18: Inverter Protection Control in Heating Mode.
The tables below display the amperage where the system will operate normally, the amperage where the inverter protection control will cause
the frequency to drop, and the amperage where the inverter protection control will shut the system off. AC input current is measured at the
inverter compressor (after the point where the current passes through the noise filter).

Due to our policy of continuous product innovation, some specications may change without notication.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp.
16
MULTI V IV Outdoor Unit Service Manual
PROTECTION CONTROLS
Phase Detection / Pressure Switch
Phase Detection
Most Multi V systems require three-phase power. The product will display the errors listed in the table below if all three phases / wires aren’t
connected correctly (one [1] or more phases missing).
Error Terminal Block Error No.
R S T
Missed Phase
X50
X
X 5
Table 19: Phase Detection Errors.
If errors occur simultaneously on two or more combined outdoor units, only the smaller outdoor unit number will be displayed. Example: If
Error No. 50 occurs on both the Master and the Slave 1 outdoor units, “501” displays on the LED (Master: ***1, Slave1: ***2).
Pressure Switch
Main PCB has a pressure sensor switch in the wiring between the inverter compressor and the power relay. The pressure sensor switch is
normally on, and has a small electric current from 220V AC.
Never touch the terminal, nor short two wires directly. It may cause physical injury or death.

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Outdoor Unit Functions
OTHER CONTROLS
Initial Setup
There are four (4) initial setup steps before operation can begin. All DIP switch settings must be completed before initial setup.
Step 1
Factory set value is displayed on the PCB LED for twenty-four (24) seconds.
Turn power on.
Code for the Master outdoor unit is
displayed for three (3) seconds.
Code for the Slave 1 outdoor unit is
displayed for three (3) seconds.
Code for the Slave 2 outdoor unit is
displayed for three (3) seconds.
Total system capacity is displayed for two
(2) seconds.
System type is displayed (2 is default).
• Heat Pump = 2
• Heat Recovery = 3
Electrical requirements are displayed.
• 208 = 22
• Heat Recovery = 46
Model Type.
14
12
10
36
2
46
1
Step 2
Communication Check: If display follows all sequences as shown above, the communication between the Master and Slave outdoor units
is normal. If the LED shows Error Code 104*, check the DIP switch settings and the communication cables between the Master and Slave
outdoor units.
Step 3
PCB Error Check: Error check will begin after forty (40) seconds.
Master / Slave unit
• All errors of all the units (including Slave) will be shown on the LED.
• If communication between main PCB and inverter PCB isn’t correct, Error Code 52* will be seen on the LED.
• If communication between main PCB and fan PCB isn’t normal, Error Code 105* will be seen on the LED.
• If any errors are displayed, check corresponding wires / cables.
Initial Setup

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18
MULTI V IV Outdoor Unit Service Manual
Initial Setup, Continued.
OTHER CONTROLS
Initial Setup
Step 4
Indoor unit auto addressing.
• Auto addressing begins after the red address button on
the Main PCB is held for six (6) seconds.
• During auto addressing, the LED on the Main PCB
displays "88".
• After auto addressing, the number of indoor units is
shown on the LED for thirty (30) seconds. The address
of the indoor unit is displayed on each wired remote
controller.
Hold red address button down for three (3) seconds.
CN_SMPS2_BL
CN_SMPS
CN6~CN10_OPTION PCB
SW01D
SW01C
SW02C
SW03C
SW04C
CN_EXT
CN_DEBUGGER
CN_CNVSS
CN3_FLASH WRITE
CN2_LGMV
CN_COMP2
CN_COMP1
CN_COMMWIRE
CN_POWER
Auto addressing begins. Auto addressing may last up to
fifteen (15) minutes. 46
The number of indoor units is displayed for thirty (30)
seconds. 35
Thirty-five (35)
indoor units
found.
Auto address process is complete. After the number of indoor
units has been displayed for thirty (30) seconds, every indoor
unit displays its address on a wired remote controller, and the
LED on the Main PCB is blank.

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Outdoor Unit Functions
Initial Setup, Continued.
Setting the Functions
Select the Mode, Function, Option, or Values using the ◄ and ►buttons. Confirm using the ● button after DIP switch No. 5 is set to on.
Mode Function Option Value Action Remarks
Content Display 1 Content Display 2 Content Display 3 Content Display 4 Implement Display 5
FDD Fdd
Refrigerant Auto Charge
(Cooling) Fn1 - - - - Operate Show the Process -
Refrigerant Auto Charge
(Heating) Fn2 - - - - Operate Show the Process -
Refrigerant Auto Amount
Judgment (Cooling) Fn3 - - - - Operate Show the Process -
Refrigerant Auto Amount
Judgment (Heating) Fn4 - - - - Operate Show the Process -
ITR (Cooling) Fn5 - - - - Operate Show the
Process -
ITR (Heating) Fn6 - - - - Operate Show the
Process -
Installation Func
Cool & Heat Selector Fn1 oFF op1~op2 Selected the
Option - - Change the Set Value Blank Saved in EPROM
Static Pressure
Compensation Fn2 oFF op1~op3 Selected the Option - - Change the Set Value Blank Saved in EPROM
Night Low Noise Fn3 oFF op1~op12 Selected the
Option - - Change the Set Value Blank Saved in EPROM
Overall Defrost Fn4 on oFF Selected the
Option - - Change the Set Value Blank Saved in EPROM
Outdoor Unit Address Fn5 - - 0~255 Set the
Value Change the Set Value Blank Saved in EPROM
Snow Removal & Rapid
Defrost Fn6 oFF op1~op3 Selected the Option - - Change the Set Value Blank Saved in EPROM
Adjusting the Indoor
Unit Capacity Fn7 op1~op2 Selected the Option - - Change the Set Value Blank Saved in EPROM
Adjusting Target
Pressure Fn8 op1~op4 Selected the Option - - Change the Set Value Blank Saved in EPROM
SVC SVC
Pump Down SE1 - - - - Start
Operation Pd -
Pump Out SE2 - - - - Start
Operation Po -
Vacuum mode SE3 - - - - Start
Operation uRcc -
Backup SE4 unit inv1~inv2 Selected the
Option - - Start Operation on off Saved in EPROM
Forced oil return SE5 - - - - Start
Operation o1 -
Forced defrost SE6 - - - - Start
Operation dEF -
Cycle data view SE7 op1~op7 - - - Show in
LED
Show Each
Numerical
Value in
Process
-
DIP-SW01 LED
SW01C ( : Confirm)
SW02C ( : Backward)
SW03C ( : Forward)
SW04C ( : Cancel)
SW01D (Reset)
ON
OFF
Functions saved in EPROM will be stored indefinitely even if the system power is reset.
OTHER CONTROLS
Initial Setup

Due to our policy of continuous product innovation, some specications may change without notication.
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20
MULTI V IV Outdoor Unit Service Manual
OTHER CONTROLS
Emergency Operation
If an inverter compressor is not operating, the system can still run by using one of two methods.
Automatic Emergency Operation (Automatic Backup Function)
If an outdoor unit detects an inverter compressor error during operation, the automatic backup mode is initiated.
1. Inverter 1 compressor automatic emergency operation.
2. Inverter 2 compressor automatic emergency operation.
Emergency Operation
Backup Mode Cancellation
Select the “off” Action By Using the ►and◄ Buttons, then Push the ● Button.
• Do not run the system under emergency operation with an inverter compressor failure for more than 48 hours. It may cause
compressor failure within the other outdoor units.
• During the emergency operation, cooling / heating capacity may be reduced.
If Slave 1 Outdoor Unit Inverter Compressor Fails
1. Ensure Slave 1 Outdoor Unit PCB No. 5 DIP Switch is Set to
ON.
2. Select the “SVC” Mode By Using the ►and◄ Buttons, then
Push the ● Button.
3. Select the “Se4” Function By Using the ►and◄ Buttons, then
Push the ● Button.
4. Select the “inv1” Option By Using the ►and◄ Buttons, then
Push the ● Button.
5. Select “Action” By Using the ►and◄ Buttons, then Push the ●
Button.
If Slave 2 Outdoor Unit Fails
1. Ensure Slave 2 Outdoor Unit PCB No. 5 DIP Switch is Set to
ON.
2. Select the “SVC” Mode By Using the ►and◄ Buttons, then
Push the ● Button.
3. Select the “Se4” Function By Using the ►and◄ Buttons, then
Push the ● Button.
4. Select the “inv1” Option By Using the ►and◄ Buttons, then
Push the ● Button.
5. Select “Action” By Using the ►and◄ Buttons, then Push the ●
Button.
SLAVE1
INV1 INV2 INV1 INV2 INV1 INV2 INV1 INV2 INV1 INV2 INV1 INV2
MASTER SLAVE1 SLAVE2 MASTER SLAVE2
Manual Emergency Operation (Manual Backup Function)
1. Verify which compressor is malfunctioning (refer to the Troubleshooting section in the back of this manual).
2. Turn off the power.
3. Set the DIP switch of the defective outdoor unit following the instructions below.
4. Turn on the power.