LG Multi V Series Instruction sheet

1
Multi V, Multi F, and Single Zone Cassette Indoor Units Install Tips
The following pages present an overview of installation of LG’s Multi V, Multi F, and Single Zone cassette indoor
units, and is intended to supplement the technical and installation information provided through www.lghvac.com.
The review of basic operation and maintenance skills must reinforce industry established practices and provide
helpful tips to make equipment operation successful.
This installation guide is NOT intended to be a replacement for LG installation manuals, nor is it intended to cover ALL the logistics of installing LG
cassette indoor units. For detailed information on the procedures mentioned here, refer to the installation manual specic to your product. Always
comply with applicable local, state, and federal codes.
Safety Instructions - Wiring
An authorized, trained technician licensed
locally and at the state level must install the
unit.
Improper installation by the user may result in
re, explosion, electric shock, physical injury or
death.
Wear protective gloves when handling equip-
ment. Sharp edges may cause personal injury.
Always check for system refrigerant leaks
after the unit has been installed or serviced.
Exposure to high concentration levels of refrig-
erant gas may lead to illness 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
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 mounting.
It may result in an accident that causes physical
injury or death.
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.
Do not store or use ammable gas or combusti-
bles near the unit.
There is risk of re, explosion, and physical injury or
death.
WARNING
DANGER
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 capa-
ble of supporting the weight of the equipment.
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 interior surfaces.
Always check for system refrigerant leaks
after the unit has been installed.
Low levels may cause product failure.
Do not make refrigerant substitutions. Use
R-410A only.
If a different refrigerant is used, or air mixes
with original refrigerant, the unit will malfunc-
tion and be damaged.
Keep the unit upright during installation to
avoid vibration or water leakage.
When connecting refrigerant tubing, remem-
ber to allow for pipe expansion.
Improper piping may cause refrigerant leaks
and system malfunction.
Do not install the unit in a noise-sensitive
area. Periodically check that the 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.
Do not use this equipment in mission crit-
ical or special-purpose applications such as
preserving foods, works of art, wine coolers
or refrigeration. This equipment is designed to
provide comfort cooling and heating.
Do not place IDUs in an environment where
the IDUs may be exposed to harmful volatile
organic compounds (VOCs), or in environ-
ments where there is improper air make up
or supply or inadequate ventilation. If there
are concerns about VOCs in the environment
where the IDUs are installed, proper air make
up or supply and/or adequate ventilation
should be provided. Additionally, in buildings
where IDUs will be exposed to VOCs, consider
a third party factory-applied epoxy coating to
the fan coils for each IDU where the entire coil
is dipped, not sprayed.
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 NEC who is equipped with the proper
tools and test instruments.
Failure to carefully read and follow all instruc-
tions in this manual can result in equipment
malfunction, property damage, personal 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.
All electric work must be performed by a
licensed electrician and conform to local build-
ing codes or, in the absence of local codes,
with the NEC, 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.
Secure all eld wiring connections with appro-
priate 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 protec-
tion 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.
High voltage electricity is required to operate
this system. Adhere to the U.S. National
Electric Code (NEC) and these instructions
when wiring.
Improper connections and inadequate ground-
ing 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.
Properly size all circuit breakers or fuses.
There is risk of re, electric shock, explosion,
physical injury or death.
Safety Instructions - Installation
DANGER
WARNING

2
Selecting the Installation Location
DANGER
To avoid the possibility of re, do not install the unit in an area where combustible gas may generate, ow,
stagnate, or leak. Failure to do so will cause serious bodily injury or death. Before beginning installation, read the
safety summary at the beginning of this manual.
Note:
Select a location for installing the indoor unit (IDU) that meets the following conditions:
• Where there is enough structural strength to bear the weight of the unit.
• Operating sound from the unit will not disturb occupants.
• Include enough space for service access.
• Include space for drainage to ensure condensate flows properly out of the unit when it is in cooling mode.
• Use a level indicator to ensure the unit is installed on a level plane.
Note:
The unit may be damaged, may malfunction, and/or will not operate as
designed if installed in any of these conditions:
Do not install the unit near a heat or steam source, or where
considerable amounts of oil, iron powder, or flour are used. These
materials may generate condensate, cause a reduction in heat ex-
changer efficiency, or malfuction of the condensate drain. If this is
a potential problem, install a ventillation fan large enough to vent
out these materials
Do not install the unit where it will be subjected to direct ther-
mal radiation from other heat sources.
Do not install the unit in an area where combustible gas may
generate, flow, stagnate, or leak. There is the possibility of fire.
Do not install the unit in a location where acidic solution and
spray (sulfur) are often used.
Do not use the unit in environments where oil, steam, or sulfu-
ric gas are present.
Do not install additional ventilation products on the chassis of
the unit.
Do not install the unit near high-frequency generator sources.
Do not install in an area where the unit will be exposed to volatile organic compounds.
Installing in an Area Exposed to Unconditioned Air
In some installation applications, areas (floors, walls) in some rooms may be exposed to unconditioned air.
The room may be above or next to an unheated garage or storeroom. To counter
this condition:
• Verify that carpet is or will be installed (carpet may increase
the temperature by three (3) degrees.
• Install radiant heat or another type of heating system to the floor.
• Add insulatiion between the floor joists.
Install a ventilation fan
with sufficient capacity
Heat or steam source
Include enough
distance
Indoor Unit
Cassette Indoor Units Installation General Information
Cassette Indoor Units Installation Tips
This document contains general installation tips for installing LG cassette indoor units (IDU). Follow all applicable local and national codes
during installation. For more detailed information, refer to the individual unit’s installation manual on www.lghvac.com.
The typical unit installation includes:
• Selecting the installation location
• Installing the unit
• Connecting refrigerant pipes
• Connecting drain pipe
• Connecting communication and power wiring
• Installing the remote controller (if applicable)
Always follow your system diagrams, including the LATS diagram (if applicable).
Installing Near a Heat or Steam Source
Ceiling Board
Unit: inch
19 -11/16
or more or more
39 - 3/8
or more
No gap
required
19 -11/16 or less
11 -13/16
“A”
Ceiling Cassette
Ceiling beam or
other obstruction
Any objects in room
(cabinets, furniture, etc.)
Floor
Ceiling
W
A
L
L
Below36 kBtu: at least 70 -7/8; not more than 11ft 9-23/32in
Over36 kBtu: at least 70 -7/8; not more than 13ft 9-11/32in
“A” =
Ceiling Board
Typical Clearances Around Installed Unit

3
Typical Cassette Unit Installation
Installing the Indoor Unit
Mounting the IDU Chassis
• The ceiling should be strong and solid enough to prevent indoor unit vibration.
• Install the unit with a slight slope towards the drainage point to ensure condensate drains
easily.
• Select and mark the areas where the hanging bolts should be placed.
WARNING
The threaded rod hangers (bolts) and hardware must be securely tightened to prevent the
unit from falling from its installation location.
There is a risk of personal injury or death from falling equipment.
• Drill the holes and install the hanging bolts (threaded rods).
• Position the IDU and secure to the hanging bolts. Use a level to ensure the IDU is level with
a slight slope to the drainage point.
Flat washer for M10
(accessory)
Flat washer for M10
(accessory)
Hanging bolt
(W3/8 or M10)
Nut
(W3/8 or M10)
Nut
(W3/8 or M10)
Spring washer
(M10)
Drill Holes for Threaded Rods
Hang Indoor Unit on Threaded Rods
Connecting Refrigerant Pipes
Refrigerant Pipe Connections
Indoor units come with flare type connections. It is the installer’s option to use the flare fittings provided or braze the indoor unit to the
refrigerant piping system.
Flare Fittings
• All unit flare fittings are 45° and are rated for high-pressure R410A refrig-
erant.
• Properly form all flare fittings using best practices.
• Place a drop of PVE oil on the outside of flare fitting before tightening.
Note:
Multi V refrigeration system components contain very small capillary tubes, small
orices, electronic expansion valves, oil separators, and heat exchangers that can
easily become blocked.
Note:
• Do not use any other type of oil (including traditional POE refriger-
ation oil) as a lubricant. Failure to follow this procedure may lead to
restrictions in the refrigeration components.
• Do not over-tighten flare nuts. Excessive tightening will cause
fittings to crack.
Insulate Refrigerant Pipes
Sufficiently insulate all cold surfaces to prevent moisture forming. All pipes must be insulated and each pipe must be separately
wrapped. Use field-provided one-half (1/2) inch thick (or thicker) closed-cell insulation. The thickness may need to be increased
based on ambient conditions and local codes.
Wrap all refrigerant and condensate piping. Glue all insulation joints with no air gaps between insulation segments, and between
insulation segments and the unit case. Ensure insulation material fits snugly against the refrigeration pipe with no air space be-
tween the pipe surface and the surrounding insulation.
Protect insulation inside hangers and supports with a second insulation layer. Ensure insulation on all pipe passing through pipe
hangers, inside conduit, and/or sleeves is not compressed.
Typical Refrigerant Line Flare Fitting Insulation Detail
No Clearance
Overlap Insulation Where the
Port and the Piping Meet
Insulation for Indoor Unit Port
(Field Supplied) Insulation for Refrigerant
Piping (Field Supplied)
Insulation Clip (Field Supplied)
Brazing
• Use a dry nitrogen purge operating at a minimum pressure of three (3) psig
and maintain a steady flow.
• Use a 15% silver phosphorous copper brazing alloy to avoid overheating and
produce good flow.
• Protect isolation valves, electronic expansion valves, and other heat-sensi-
tive components from excessive heat with a wet rag or heat barrier spray.
Set screw (4)
for paper pattern
Paper pattern
Ceiling board
Ceiling
Distance of bolt
from bracket: 1-1/2
Open ceiling board
along outer edge
of paper pattern
Ceiling Cassette
Chassis
Ceiling board
Distance between chassis
and ceiling surface:
19/32 for TM/TN/TP chassis
1-7/32 to 1-11/32 for TQ/TR chassis
Unit: inch
5-7/8 (TM/TN/TP/TQ/TR chassis)
3-9/16 (TL chassis)
2-3/16 (TU/TT chassis)

4
Connecting the Drain Pipe
Condensate Drain Pipe
All cassette indoor units have a factory-mounted condensate pump that
runs continuously while the unit is in cooling mode. The pump has an
internal high-level float switch that stops the unit if the water level in the
pan rises too high.
All cassette indoor units have a flexible drain hose kit and one or two
clamps. The hose can be used to connect the condensate pipe to the con-
densate pump connection.
• Indoor units DO NOT come with check valves or a backflow prevention
device. If check valves are needed, they must be field supplied.
• The maximum lift of all condensate pumps is 27 in.
• Measure lift distance from the bottom surface of the indoor unit, NOT
from the condensate pipe connection.
• Slope all horizontal condensate pipe segments a minimum of 1/4 inch
per foot away from the indoor unit.
• Ceiling cassette indoor units do not have a gravity condensate pipe con-
nection. There is a service drain plug on the bottom of each unit under
the decorative panel. This drain plug is intended as a service feature and
is not to be used as a permanent gravity drain connection.
1/50~1/100
slope
Hanger distance
3.3~4.9 feet Hanger Bracket
Flexible drain hose
Insulation
Metal
clamp
Max.
11-13/16 inches
PVC Piping
PVC Elbow
Drain pump
Max.
27 in. lift
Typical Indoor Unit Drain Pump to Drain Piping System
Configuration
Connecting Communication and Power Wiring
Connecting Communication and Power Wiring
Indoor unit installation best practices are to connect control wiring (low voltage) and then connect power wiring (high voltage). Do not apply power
to the indoor unit or any system component until authorized to do so by the system commissioning agent.
DANGER
High voltage electricity is required to operate this system. Adhere to National Electrical Codes and these instructions when wiring.
Improper connections and inadequate grounding can cause accidental injury or death.
Always ground the unit following local, state, and National Electrical Codes.
Improper connections and inadequate grounding can cause accidental injury or death.
Properly size all circuit breakers or fuses.
There is risk of re, electric shock, explosion, physical injury or death.
WARNING
The information contained in this manual is intended for use by a trained electrician familiar with applicable local codes and the U.S.
National Electric Code (NEC), and who is equipped with the proper tools and test instruments.
Failure to carefully read and follow all instructions in this manual can result in personal injury or death.
Connect the indoor unit input power cable but do not apply power to the indoor unit until authorized to do so by the system commis-
sioning agent.
Inappropriate power connection can result in personal 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, resulting in physical injury or death.
Properly tighten all power connections.
Loose wiring may overheat at connection points, causing a re, physical injury or death.
Don’ts
• Never use wire caps and never splice communications cables.
• Star and Wye communications cable configurations are not acceptable.
• Never connect zone controllers or other central control products such as AC Smart, PDI, or LG building management system gateway
products to the IDU/ODU communications cable.
Multi V Indoor Unit Wiring Configuration
Multi V IDUs require separate power and communication cables. The IDU
requires single-phase, 208-230 volt facility power. Be sure the powier
cables meet applicable local and national codes.
The field-supplied communications cable from the outdoor unit must
be minimum 18-2, stranded and shielded. Polarity matters for commu-
nication cable. When connecting the communications cable conductors
at each Multi V system component, be careful the conductor connected
to the IDU(A) terminal on the outdoor unit is connected to the A/3(A)
terminal at each indoor unit. The conductor connected to the IDU(B)
terminal on the outdoor unit must be connected to the B/4(B) terminals
at each indoor unit. Cross connecting the A/3(A) and B/4(B) terminals
will cause communications errors and system malfunction. Communica-
tion cables must be connected in a daisy chain configuration.
Typical Multi V 4-way Cassette IDU Power Wiring and Communications
Cable Terminals
Lock nut
Conduit
mounting
plate
Conduit
1(L1) 2(L2)
Power Supply
208/230V
1(L1) 2(L2) 3(A) 4(B)
Communication
Cable

5
Connecting Communication and Power Wiring - continued
• Keep communications cables away from line voltage wiring, lighting ballasts, and other devices emitting
EMF energy. Maintain a minimum of two (2) inches between line voltage wires and communications or zone
controller cables.
• Field provide a minimum of 18-2 AWG, stranded and shielded, PVC or vinyl jacket communications wiring
between the indoor units, heat recovery boxes (if applicable), and outdoor units.
• The outdoor/indoor unit communications cable must be run between components in a daisy chain configu-
ration. Star or wye configurations are not allowed.
• Connect the communications cables to the A/3(A) and B/4(B) terminals at indoor units and/or heat recov-
ery units. Maintain polarity throughout the communications bus. Be sure A/3(A) terminals are connected to
A/3(A) terminals and B/4(B) terminals are connected to B/4(B) terminals.
• Connect the shields of the communications cable segments together at each indoor unit. Insulate each
shield connection to prevent electrical contact with the IDU. Ground the shield of the communications cable
at one end only, at the master outdoor unit.
Multi F and Single Zone Indoor Unit Wiring Configuration
Multi F and Single Zone IDUs have a single cable from the outdoor unit that supplies both power and commu-
nication. This field-supplied cable must be minimum 18-4 stranded and shielded. Be sure the power conduc-
tors are connected to the line power terminals of the IDU. Be sure the communication conductor is connect-
ed to the communication terminal of the IDU and ground is connected to ground.
Power Supply
(208/230V)
L(L1) L(L2) 3L(L1)
L(L2)
3Communications
Ground
Typical Multi F and Single Zone IDU Power Wiring
and Communications Cable Terminals
Optional Wired Wall Controller Installation
Since the room temperature sensor is inside the remote controller, to maintain proper space temperature install the remote controller in a
place away from direct sunlight, high humidity, and direct supply of hot or cold air. Install the remote controller about 5 ft above the floor in
an area with good air circulation and an average temperature.
Do not install the remote controller where it can be affected by the following:
• Drafts or dead spots behind doors and in corners
• Hot or cold air from ducts
• Radiant heat from sun or appliances
• Concealed pipes and chimneys
• Uncontrolled areas such as an outside wall behind the remote controller
1. Pull communications cable between the zone controller handy box (if used) and
the indoor unit. Use field supplied 22-3 twisted, stranded and unshielded cable
or LG supplied cable.
2. Store a minimal amount of cable in the handy box. Any additional cable should be
coiled and stored near the indoor unit control panel.
3. If using LG cable and additional cable length is needed, order a thirty-three (33)
foot LG Wired Remote Group Control Extension cable (Model No. PZCWRC1).
4. If using LG supplied cable and the cable between the zone controller and the
indoor unit is too long, do not cut the cable and shorten. Coil any spare commu-
nications cable, tie-wrap it, and leave it next to the indoor unit location.
5ft
no
no
no
yes
RemoteController
TEMP
RemoteController
TEMP
RemoteController
TEMP
Typical Wired Remote Controller Installation
Lock nut
Conduit
1(L1) 2(L2)
3(A) 4(B)
Power Supply
High Voltage
(208/230V)
Communications
Typical Multi V 2-way Cassette IDU Power Wiring and Communications
Cable Terminals
1(L1) 2(L2)
3(A) 4(B)
Power Supply
High Voltage
(208/230V)
Communications
Lock nut
Conduit
mounting
plate
Conduit
Typical Multi V 1-way Cassette IDU Power Wiring and Communications
Cable Terminals

6
New Issue: TT_LG_Cassette_IDU_Install_Tips_3_19
To access complete Installation Manuals
visit www.lghvac.com/resources
This document, as well as all reports, illustrations, data, information, and other materials are the property of LG Electronics U.S.A., Inc.,
and are disclosed by LG Electronics U.S.A., Inc. only in confidence.
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.