LG MT11AH User manual

www.lg.com
INSTALLATION MANUAL
AIR CONDITIONER
• Please read this installation manual completely before installing the product.
• Installation work must be performed in accordance with the national wiring
standards by authorized personnel only.
• Please retain this installation manual for future reference after reading it
thoroughly.
TYPE : CEILING CASSETTE
P/NO : MFL42291407
ENGLISH ITALIANO ESPAÑOL FRANÇAIS DEUTSCH

2Multi-Type Air Conditioner
Multi Type Air Conditioner Installation Manual
CONTENTS
Safety Precautions..........................................................................................3
Installation of Indoor ......................................................................................6
Test running ..................................................................................................19
Optional Operation ........................................................................................21
OUT-LINE OF INSTALLATION
1) Selection of the best location......................6
2) Ceiling opening dimensions and hanging
bolt location(unit: mm) ................................8
3) The Indoor Unit Installation.........................9
4) Remote Controller Installation ...................9
5) Wiring Connection ....................................12
ELECTRICAL WIRING .............................13
6) Connecting Pipes to the Indoor Unit.........14
PIPING CONNECTION.............................15
7) Installation of Decorative Panel ................16
8) Indoor Unit Drain Piping ...........................18
HEAT INSULATION ..................................19
1) PRECAUTIONS IN TEST RUN ................19
CHECK THE FOLLOWING ITEMS WHEN
INSTALLATION IS COMPLETE................19
2) Connection of power supply .....................20
3) Evaluation of the performance..................20
1) Test Run Mode .......................................21
2) Setting Address of Central Control ...........22
3) Thermistor ................................................23
4) Ceiling Height Selection............................24
5) Group Setting............................................25
6) Dry Contact Mode Setting ........................26
7) Celsius / Fahrenheit Switching .................27
8) Optional Function Setting .........................28
Installer Setting Code Table ..........................29

Safety Precautions
Installation Manual 3
ENGLISH
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.
WARNING
Be sure not to do.
Be sure to follow the instruction.
Safety Precautions
■Installation
Always install a dedicated circuit and breaker.
• Improper wiring or installation may cause fire
or electric shock
Use the correctly rated breaker or fuse.
• There is risk of fire or electric shock.
Do not use a defective or underrated circuit
breaker. Use this appliance on a dedicated
circuit.
• There is risk of fire or electric shock.
For electrical work, contact the dealer, seller, a
qualified electrician, or an Authorized Service
Center.
• Do not disassemble or repair the product. There
is risk of fire or electric shock.
Always ground the product.
• There is risk of fire or electric shock.
Install the panel and the cover of control box
securely.
• There is risk of fire or electric shock.

4Multi-Type Air Conditioner
Safety Precautions
Do not modify or extend the power cable.
• There is risk of fire or electric shock.
Be cautious when unpacking and installing the
product.
• Sharp edges could cause injury. Be especially
careful of the case edges and the fins on the
condenser and evaporator.
For installation, always contact the dealer or an
Authorized Service Center.
• There is risk of fire, electric shock, explosion,
or injury.
Do not install the product on a defective
installation stand.
• It may cause injury, accident, or damage to
the product.
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
personal injury.
Do not let the air conditioner run for a long time when
the humidity is very high and a door or a window is
left open.
• Moisture may condense and wet or damage
furniture.
Do not store or use flammable gas or combustibles near the product.
• There is risk of fire or failure of product.
Use a vacuum pump or Inert (nitrogen) gas when doing leakage test or air purge. Do not compress air or
oxygen and do not use flammable gases. Otherwise, it may cause fire or explosion.
• There is risk of fire or failure of product.
nOperation

Safety Precautions
Installation Manual 5
ENGLISH
Always check for gas (refrigerant) leakage after
installation or repair of product.
• Low refrigerant levels may cause failure of
product.
Install the drain hose to ensure that water is
drained away properly.
• A bad connection may cause water leakage.
Keep level even when installing the product.
• To avoid vibration or water leakage.
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.
Use two or more people to lift and transport the
product.
• Avoid personal injury.
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.
CAUTION
■Installation

6Multi-Type Air Conditioner
Installation of Indoo
Installation of Indoor
1. Indoor unit
• There should not be any heat source or
steam near the unit.
• There should not be any obstacles to
prevent the air circulation.
• A place where air circulation in the room
will be good.
• A place where drainage can be easily
obtained.
• A place where noise prevention is taken
into consideration.
• Do not install the unit near the door way.
• Ensure the spaces indicated by arrows
from the wall, ceiling, or other obstacles.
• The indoor unit must keep the
maintenance space.
Selection of the best location
Unit:cm
Ceiling
Ceiling Board Ceiling Board
30 or more
Above 250 330 or less
100 or more
50 or
more
50 or
more
30 or less
Floor
More than
30cm
Unit:cm
Ceiling
Ceiling Board
Ceiling Board
20 or more
Above 250 330 or less
100 or more
50 or
more
50 or
more
30 or less
Floor
❈Please use an annexed sheet or the
corrugated cardboard on the bottom of
packing as installation sheet.
❈When using the bottom sheet, please use it
after separating the installation sheet from
packing of the product floor by using a knife
etc as a picture below.
Annexed sheet
Or
Packing corrugated
cardboard on the
bottom

Installation of Indoor
Installation Manual 7
ENGLISH
• Select and mark the position for fixing bolts
and piping hole.
• Decide the position for fixing bolts slightly tilted
to the drain direction after considering the
direction of drain hose.
• Drill the hole for anchor bolt on the wall.
CAUTION:
• This air-conditioner uses a drain pump.
• Horizontly install the unit using a level
gauge.
•
During the installation, care should be
taken not to damage electric wires.
Ceiling opening dimensions and hanging bolt location
• The dimensions of the paper model for installing are the same as those of the ceiling opening dimensions.
Ceiling board
Level gauge
Ceiling
1,000 (Ceiling opening)
931.6
893.4 (Hanging bolt)
330 (Hanging bolt)
860
390
60
450 (Ceiling opening)
60
Unit: mm
585~660
517
461
517
585~660
523
570
570
319
Unit: mm
875
787
684 671 875
840
840

Set screw of
paper model (4 pieces)
Paper model
for installation
Ceiling board
150mm
Adjust the same height
Ceiling board
Ceiling
Flat washer for M10
(accessory)
Keep the length of the bolt
from the bracket to 40mm
Open the ceiling board
along the outer edge of the
paper model
Flat washer for M10
(accessory)
Hanging bolt
(W3/8 or M10)
Nut
(W3/8 or M10)
Nut
(W3/8 or M10)
Spring washer
(M10)
Air Conditioner body
Installation of Indoor
The Indoor Unit Installation
8Multi-Type Air Conditioner
2. Avoid installing air conditioner in such circumstances where cutting oil mist or iron powder is in
suspension in factories, etc.
3. Avoid places where inflammable gas is generated, flows in, is stored or vented.
4. Avoid places where sulfurous acid gas or corrosive gas is generated.
5. Avoid places near high frequency generators.
• Thoroughly study the following installation locations:
1. In such places as restaurants and kitchens, considerable amount of oil steam and flour
adhere to the turbo fan, the fin of the heat exchanger and the drain pump, resulting in heat
exchange reduction, spraying, dispersing of water drops, drain pump malfunction, etc.
In these cases, take the following actions:
• Make sure that the ventilation fan for smoke-collecting hood on a cooking table has sufficient
capacity so that it draws oily steam which should not flow into the suction of the air
conditioner.
• Make enough distance from a cooking room to install the air conditioner in such a place
where it may not suck in oily steam.
NOTICE
Use the ventilation fan
for smoke-collecting
hood with sufficient
capacity.
Cooking table
Air conditioner
Take enough
distance

ENGLISH
Wall
5~7mm
Indoor Outdoor
Set screw of
paper model (4 pieces)
Paper model
for installation
Ceiling board
90mm
Adjust the same height
Ceiling board
Ceiling
Flat washer for M10
(accessory)
Keep the length of the bolt
from the bracket to 40mm
Open the ceiling board
along the outer edge of the
paper model
Flat washer for M10
(accessory)
Hanging bolt
(W3/8 or M10)
Nut
(W3/8 or M10)
Nut
(W3/8 or M10)
Spring washer
(M10)
Air Conditioner body
Keep the length of *( )mm between
the air conditioner bottom surface
and the ceiling surface
Installation Manual 9
Installation of Indoor
• The following parts is option.
① Hanging Bolt - W 3/8 or M10
② Nut - W 3/8 or M10
③ Spring Washer - M10
④ Plate Washer - M10
CAUTION: Tighten the nut and
bolt to prevent unit falling.
• Drill the piping hole on the wall slightly tilted to the
outdoor side using a Ø 70 hole-core drill.
*( ) →TQ/TR : 31~34mm
TP : 15mm

10 Multi-Type Air Conditioner
Installation of Indoor
Remote Controller Installation
1
2
3
2
3
<Wire guide grooves>
1. Please fix tightly using provided screw after placing remote controller setup
board on the place where you like to setup.
- Please set it up not to bend because poor setup could take place if setup board bends.
Please set up remote controller board fit to the reclamation box if there is a reclamation box.
- Install the product so as not to make a gap with the wall side and to prevent shaking after the installation.
2. Can set up Wired remote controller cable into three directions.
- Setup direction: the surface of wall reclamation, upper, right
- If setting up remote controller cable into upper and right side, please set up after removing remote controller
cable guide groove.
❈ Remove guide groove with long nose.
①
Reclamation to the surface of the wall
②
Upper part guide groove
③
Right part guide groove

Installation of Indoor
Installation Manual 11
ENGLISH
Wall
Side
Wall
Side
Wall
Side
Wall
Side
<Connecting order>
<Separating order>
3. Please fix remote controller upper part into
the setup board attached to the surface of
the wall, as the picture below, and then,
connect with setup board by pressing lower
part.
- Please connect not to make a gap at the remote controller
and setup boardʼs upper and lower, right and left part.
- Before assembly with the installation board, arrange the
Cable not to interfere with circuit parts.
When separating remote controller from
setup board, as the picture below, after
inserting into the lower separating hole using
screw driver and then, spinning clockwise,
remote controller is separated.
- There are two separating holes. Please individually
separate one at a time.
- Please be careful not to damage the inside
components when separating.
4. Please connect indoor unit and remote controller using connection cable.
5. Please use extension cable if the distance between wired remote controller and
indoor unit is more than 10m.
Please check if connector is normally connected.
Connecting cable
Indoor
Unit side
When installing the wired remote controller, do not bury it in the wall.
(It can cause damage in the temperature sensor.)
Do not install the cable to be 50m or above.
(It can cause communication error.)
• When installing the extension cable, check the connecting direction of the connector of the remote controller
side and the product side for correct installation.
• If you install the extension cable in the opposite direction, the connector will not be connected.
• Specification of extension cable: 2547 1007 22# 2 core 3 shield 5 or above.
CAUTION
12V Red
Signal Yellow
GND Black

12 Multi-Type Air Conditioner
Installation of Indoor
Wiring Connection
• Open the control box cover and connect the Remote controller cord and Indoor power wires.
Remote Controller
Cable
Connecting
Cable
Terminal Block of Outdoor Unit
L N 1(L) 2(N) 3 4 1(L) 2(N) 3 4 5
Terminal Block of Indoor Unit
POWER INPUT
OPTION
TO AIR
FRESH
KIT
Electricwire
Round crimp-style terminal
Attach insulation sleeve
Connect wires of the same gauge to both sides
WARNING: Make sure that the screws of the terminal are free from
looseness.

ENGLISH
Installation Manual 13
Installation of Indoor
ELECTRICAL WIRING
1. All wiring must comply with LOCAL REGULATIONS.
2. Select a power source that is capable of supplying the current required by the air conditioner.
3. Feed the power source to the unit via a distribution switch board designed for this purpose.
4. The terminal screws inside the control box may be loose due to vibration during transport.
Check the screws for loose connection.
(Running the air conditioner with loose connection can overload and damage electrical
components.)
5. Always ground the air conditioner with a grounding wire and connector to meet the LOCAL
REGULATION.

14 Multi-Type Air Conditioner
Installation of Indoor
Connecting Pipes to the Indoor Unit
Preparation of Piping
Main cause of gas leakage is defect in flaring
work. Carry out correct flaring work in the
following procedure.
1. Cut the pipes and the cable.
• Use the accessory piping kit or the pipes
purchased locally.
• Measure the distance between the indoor
and the outdoor unit.
• Cut the pipes a little longer than measured
distance.
•
Cut the cable 1.5m longer than the pipe
length.
2. Burrs removal
• Completely remove all burrs from the cut
cross section of pipe/tube.
•
Put the end of the copper tube/pipe to
downward direction as you remove burrs in
order to avoid to let burrs drop in the tubing.
3. Putting nut on
• Remove flare nuts attached to indoor and
outdoor units, than put them on pipe/tube
having completed burr removal.
(Not possible to put them on after flaring work)
4. Flaring work
• Carry out flaring work using dedicated
flaring tool for R-410A as shown below.
Firmly hold copper tube in a bar(or die) as
indicated dimension in the table above.
5. Check
• Compare the flared work with figure below.
• If flare is noted to be defective, cut off the
flared section and do flaring work again.
Copper
tube
90 Slanted Uneven Rough
Pipe
Reamer
Point down
Flare nut
Copper tube
Bar
Copper pipe
Clamp handle Red arrow mark
Cone
Yoke
Handle
Bar
"A"
Inclined
Inside is shining without scratches
Smooth all round
Even length
all round
Surface
damaged Cracked Uneven thickness
= Improper flaring =
Outside diameter A
mm inch mm
Ø6.35 1/4 1.1~1.3
Ø9.52 3/8 1.5~1.7
Ø12.7 1/2 1.6~1.8
Ø15.88 5/8 1.6~1.8
Ø19.05 3/4 1.9~2.1

ENGLISH
Installation of Indoor
Installation Manual 15
Piping Connection
1. Form the piping according to its routing.
Avoid bending and bending back the same
piping point more than three times. (This will
result in hardening the pipe.)
2. After deforming the piping, align centers of the
union fitting of the indoor unit and the piping,
and tighten them firmly with wrenches.
3. Connect pipe to the service valve or ball
valve which is located below the outdoor unit.
4. After completing the piping connection, be
sure to check if there is gas leakage in indoor
and outdoor connection.
Vacuum drying
After completing the piping connection, execute vacuum
drying for the connecting piping and the indoor unit.
The vacuum drying must be carried out using the
service ports of both the liquid and gas side valves.
Connection of the pipes
1. When piping installation work you must be
used the connector.
Connecting pipe size
Outdoor
unit
Liquid side
Flare connection
Flare connection
Gas side
Indoor
unit
AB
Gas side Liquid side
ABA B
24k Ø15.88 Ø12.7 Ø9.52 Ø6.35
30k, 36k - - Ø9.52 Ø6.35
Indoor Units
Indoor Units Gas side Liquid side
7k, 9k, 12k Ø9.52 Ø6.35
18k, 24k Ø12.7 Ø6.35
30k, 36k Ø15.88 Ø6.35
Flare nut fastening torque
mm inch kgf.m
Ø6.35 1/4 1.8~2.5
Ø9.52 3/8 3.4~4.2
Ø12.7 1/2 5.5~6.6
Ø15.88 5/8 6.3~8.2
Ø19.05 3/4 9.9~12.1
2. Align the center of the pipings and sufficiently tighten the flare nut by hand
3. Finally, tighten the flare nut with torque wrench until the wrench clicks.
■When tightening the flare nut with torque wrench, ensure the direction for tightening follows the
arrow on the wrench.
CAUTION: Use two wrenches and tighten with regular torque.

Installation of Decorative Panel
Installation of Indoor
16 Multi-Type Air Conditioner
The decorative panel has its installation direction.
Before installing the decorative panel, always remove the paper template.
1. Remove the packing and take out air inlet
grille from front panel.
2. Remove the Corner covers of the panel.
3. Fit the panel on the unit by inserting
hooks as shown in picture.
4. Insert two screws on diagonal corners of
panel. Do not tighten the bolts
completely. (The fixing screws are
included in the indoor unit box.)
Check the alignment of panel with the
ceiling. Height can be adjusted using
hanging bolts as shown in picture. Insert
the other two screws and tighten all
screws completely.
Front grille
Coner cover
Hook clip
Hook

Installation Manual 17
ENGLISH
Installation of Indoor
5. Fit the corner covers.
6. Open two screws of control panel cover.
7. Connect one display connector and two
vane control connectors of front panel to
indoor unit PCB.
The position marking on PCB is as:
Display connector : CN-DISPLAY
Vane control connector: CN-VANE 1,2
8. Close the cover for control box.
9. Install the air inlet grille and Filter on the
panel.
Screw
CN-VANE 1,2 CN-DISPLAY

CAUTION: Install certainly the decorative panel.
Cool air leakage causes sweating. Water drops fall.
• Drain piping must have down-slope (1/50 to
1/100): be sure not to provide up-and-down
slope to prevent reversal flow.
• During drain piping connection, be careful
not to exert extra force on the drain port on
the indoor unit.
• The outside diameter of the drain
connection on the indoor unit is 32mm.
• Be sure to execute heat insulation on the
drain piping.
DRAIN TEST
The air conditioner uses a drain pump to drain water.
Use the following procedure to test the drain pump operation:
• Connect the main drain pipe to the exterior and leave
it provisionally until the test comes to an end.
• Feed water to the flexible drain hose and check the
piping for leakage.
• Be sure to check the drain pump for normal
operating and noise when electrical wiring is
complete.
• When the test is complete, connect the flexible drain
hose to the drain port on the indoor unit.
Air conditioner
unit
Ceiling
board
Decorative panel Decorative
panel
Fit the insulator (this part) and
be careful for cool air leakage
Good example
Air
Cool air leakage
(no good)
Bad example
Ceiling
board
Air conditioner unit
Flexible drain hose
Maintenance
drain port
Upward
routing
not allowed
Pipe clamp
Indoor unit
1/50~1/100
MAX 700mm
Flexible drain hose
Feed water
Drain Pump
Drain pan
Flexible drain hose
(accessory)
Main
drain pipe
Glue the joint
Drain
port
Drain hose connection
Use the clip (accessory)
Flexible drain hose
Piping material: Polyvinyl chloride pipe VP-25
and pipe fittings
Heat insulation material: Polyethylene foam with thickness more than 8 mm.
Indoor Unit Drain Piping
18 Multi-Type Air Conditioner
Installation of Indoor

Installation of Indoor
Installation Manual 19
ENGLISH
HEAT INSULATION
1. Use the heat insulation material for the refrigerant piping which has an excellent heat-
resistance (over 120°C).
2. Precautions in high humidity
circumstance:
This air conditioner has been tested
according to the "KS Standard
Conditions with Mist" and confirmed
that there is not any default. However, if
it is operated for a long time in high
humid atmosphere (dew point
temperature: more than 23°C), water
drops are liable to fall. In this case, add
heat insulation material according to the
following procedure:
• Heat insulation material to be prepared... Adiabatic glass wool with thickness 10 to 20mm.
• Stick glass wool on all air conditioners that are located in ceiling atmosphere.
Indoor unit
Thermal insulator
(accessory)
Fastening band
(accessory)
Refrigerant piping
1. PRECAUTIONS IN TEST RUN
• The initial power supply must provide at least 90% of the rated voltage.
Otherwise, the air conditioner should not be operated.
CAUTION ①For test run, carry out the cooling operation firstly even during heating
season. If heating operation is carried out firstly, it leads to the trouble
of compressor. Then attention must be paid.
② Carry out the test run more than 5 minutes without fail.
(Test run will be cancelled 18 minutes later automatically)
• The test run is started by pressing the room temperature checking button and down timer
button for 3 seconds at the same time.
• To cancel the test run, press any button.
CHECK THE FOLLOWING ITEMS WHEN INSTALLATION IS COMPLETE
• After completing work, be sure to measure and record trial run properties, and store measured
data, etc.
• Measuring items are room temperature, outside temperature, suction temperature, blow out
temperature, wind velocity, wind volume, voltage, current, presence of abnormal vibration and
noise, operating pressure, piping temperature, compressive pressure.
• As to the structure and appearance, check following items.
□Is the circulation of air adequate?
□Is the draining smooth?
□Is the heat insulation complete
(refrigerant and drain piping)?
□Is there any leakage of refrigerant?
□Is the remote controller switch operated?
□Is there any faulty wiring?
□Are not terminal screws loosened?
M4......118N.cm{12kgf.cm} M5......196N.cm{20kgf.cm}
M6......245N.cm{25kgf.cm} M8......588N.cm{60kgf.cm}
Test running

20 Multi-Type Air Conditioner
Test running
2. Connection of power supply
1. Connect the power supply cord to the independent power supply.
• Circuit breaker is required.
2. Operate the unit for fifteen minutes or more.
3. Evaluation of the performance
1. Measure the temperature of the
intake and discharge air.
2. Ensure the difference between the
intake temperature and the discharge
one is more than 8°C (Cooling) or
reversely (Heating).
CAUTION: After the confirmation of the above conditions, prepare the wiring as follows:
1) Never fail to have an individual power specialized for the air conditioner. As for the method
of wiring, be guided by the circuit diagram pasted on the inside of control box cover.
2) Provide a circuit breaker switch between power source and the unit.
3) The screw which fasten the wiring in the casing of electrical fittings are liable to come
loose from vibrations to which the unit is subjected during the course of transportation.
Check them and make sure that they are all tightly fastened. (If they are loose, it could give
rise to burn-out of the wires.)
4) Specification of power source
5) Confirm that electrical capacity is sufficient.
6) Be sure that the starting voltage is maintained at more than 90 percent of the rated voltage
marked on the name plate.
7) Confirm that the cable thickness is as specified in the power sources specification.
(Particularly note the relation between cable length and thickness.)
8) Never fail to equip a leakage breaker where it is wet or moist.
9) The following troubles would be caused by voltage drop-down.
• Vibration of a magnetic switch, damage on the contact point there of, fuse breaking, disturbance
to the normal function of a overload protection device.
• Proper starting power is not given to the compressor.
HAND OVER
Teach the customer the operation and maintenance procedures, using the operation manual
(air filter cleaning, temperature control, etc.).
Thermometer