Trane 4MXC8512B10N0 User guide

Installer’s Manual
Split System (R-410A)
Air Handler for
Multi-Split
Inverter System
12,000 Btu/h to 24,000 Btu/h
Cassette Type Models:
4MXC8512B10N0
4MXC8518B10N0
4MXC8524B10N0
May 2021 MS-SVN36D-EN

WARNING
This equipment is to be serviced by professionally trained personnel
ONLY. Under NO circumstances should an unqualified person service it.
This equipment contains refrigerant under PRESSURE and operates at
HIGH VOLTAGE. Improperly installed, adjusted or altered equipment by an
unqualified person poses safety hazards including FIRE, ELECTROCUTION,
or EXPLOSION, which could result in death or serious injury.
Warnings and Cautions
Warnings and Cautions. Warnings are provided to alert installing
contractors to potential hazards that could result in personal injury or
death, while cautions are designed to alert personnel to conditions that
could result in equipment damage.
Your personal safety and the proper operation of this machine depend
upon the strict observance of these precautions.
Attention: Warnings and Cautions appear at appropriate sections
throughout this literature. Read these carefully.
WARNING: Indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury.
CAUTION: Indicates a potentially hazardous situation which, if not
avoided, could result in minor or moderate injury. It may also be used
to alert against unsafe practices.
NOTICE:Indicates a situation that could result in equipment or
property damage only accidents.
WARNING
Electrocution and Fire Hazards with Improperly Installed and Grounded
Field Wiring!
Improperly installed and grounded field wiring poses FIRE &
ELECTROCUTION hazards.To avoid these hazards, you MUST follow
requirements for field wiring installation and grounding as described in
the National Electrical Codes (NEC) and your local/state electrical codes.
All field wiring MUST be performed by qualified personnel.
Failure to follow these requirements could result in death or serious injury.

Warnings and Cautions
WARNING
R-410A Refrigerant under Higher Pressure than R-22!
The units described in this manual uses R410-A refrigerant which operates at 50 to 70%
higher pressures than R-22. Use only R-410A approved service equipment. Refrigerant
cylinders are painted with "pink" color to indicate the type of refrigerant and may contain
a "dip" tube to allow for charging of liquid refrigerant into the system. For specific handling
concerns with R-410A, please contact your local sales office.
Failure to use R-410A approved service equipment could result in standard equipment
exploding under R-410A higher pressure which could result in death or serious injury.
NOTICE
Use PVE Oil with R-410A Mini Split Units!
Most R-410A mini-splits use a PVE oil (Polyvinyl Ether Oil) that readily absorbs moisture
from the atmosphere.To limit this "hygroscopic" action, the system should remain sealed
whenever possible. If a system has been open to the atmosphere for more than 4 hours,
the compressor oil must be replaced. Never break a vacuum with air and always change
the driers when opening the system for component replacement. For specific handling
concerns with the PVE oil, contact your local sales office.
USE ONLY THE FACTORY RECOMMENDED - DAFNE HERMETIC OIL FV50S - for servicing
multi-splits other than 4TXM2218A12N and 4TXM2221A13N. (4TXM2218A12N and
4TXM2221A13N can use POE oil.)
Important!
Environmental Concerns
Scientific research has shown that certain man-made chemicals can affect the earth's naturally occurring
stratospheric ozone layer when released to the atmosphere. In particular, several of the identified chemicals
that may affect the ozone layer are refrigerants that contain chlorofluorocarbons (CFC's) and those containing
hydrochlorofluorocarbons (HCFC's). Not all refrigerants containing these compounds have the same potential
impact to the environment.The Company advocates the responsible handling of all refrigerants, including
industry replacements for CFC's such as HCFC's and HFC's.
Responsible Refrigerant Practices
The manufacturer believes that responsible refrigerant practices are important to the environment, our
customers, and the air conditioning industry. All technicians who handle refrigerants must be certified.The
Federal Clean Air Act (Section 608) sets forth the requirements for handling, reclaiming, recovering and recycling
of certain refrigerants and the equipment that is used in these service procedures. In addition, some states or
municipalities may have additional requirements that must also be adhered to for responsible management of
refrigerants. Know the applicable laws and follow them.

Contents
Safety Precautions .................................................................................................................... 5
Pre-Installation Checklist........................................................................................................... 6
Cassette Components............................................................................................................... 7
Clearance Requirements........................................................................................................... 7
Refrigerant Piping Requirements .............................................................................................. 8
Installation Location................................................................................................................... 9
Installing the Indoor Unit.......................................................................................................... 10
Mounting Location ................................................................................................................... 10
Dimension of Ceiling Opening and Location of the Expansion Bolts ...................................... 11
Hoisting the Main Body of the Unit .......................................................................................... 12
Installation of the Condensate Pipe......................................................................................... 13
Design of the Condensate Pipe............................................................................................... 13
Precautions for the Drain Pipe................................................................................................. 14
Test the Drainage System ....................................................................................................... 15
Connecting the Pipe at the Indoor Unit.................................................................................... 16
Installation of the Refrigerant Piping........................................................................................ 17
Flare Processing...................................................................................................................... 17
Bending Pipes ......................................................................................................................... 17
Connecting the Pipe at the Outdoor Units............................................................................... 18
Insulation of the Pipe Joints..................................................................................................... 19
Wiring the Indoor Unit.............................................................................................................. 19
Stranded Wiring....................................................................................................................... 21
Electrical Wiring....................................................................................................................... 22
Wiring Precautions .................................................................................................................. 22
Electrical Cable Connection .................................................................................................... 22
Grounding Requirements ........................................................................................................ 23
Installation of Controllers......................................................................................................... 23
Install the Panel ...................................................................................................................... 24
Installation Checklist ............................................................................................................... 26
Test Operation ......................................................................................................................... 26
Wiring Diagrams...................................................................................................................... 26
Indoor Unit Dimensions ........................................................................................................... 28
Error Codes ............................................................................................................................. 29
Troubleshooting....................................................................................................................... 31
General Maintenance .............................................................................................................. 32
Cleaning the Air Inlet Grille ..................................................................................................... 33
Changing the Air Purier Filters............................................................................................... 33
Check Before Seasonal Use .................................................................................................. 34
Maintenance After Seasonal Use ............................................................................................ 34
After Sales Service.................................................................................................................. 34

5
Cassette Unit
WARNING This mark indicates a potentially hazardous situation which, if not avoided,
could result in death or serious injury.
CAUTION
This mark indicates a potentially hazardous situation which, if not avoided,
could result in minor or moderate injury. It may also be used to alert against
unsafe practices.
NOTICE This mark indicates a situation which could result in equipment and/or
property damage
Safety Precautions
Warnings, Cautions and Notices: Warnings, cautions and notices appear at appropriate intervals throughout
this manual. Warnings are provided to alert installing contractors to potential hazards that could result in
serious injury or death. Cautions are designed to alert personnel to conditions that could result in minor to
moderate injury. Notices alert to the possibility of equipment and/or property damage.
Your personal safety and the proper operation of this machine depend upon the strict observance of these
precautions.
WARNING
1. Installation should be left to the dealer or another professional. Improper installation may cause
water leakage, electrical shock or re.
2. Install the air conditioner according to the instructions given in this manual. Incomplete installation
work may cause water leakage, electrical shock or re.
3. Be sure to use the supplied or specied installation parts. Use of other parts may cause the unit to
come loose, resulting in water leakage, electrical shock or re.
4. Install the air conditioner on a solid base that can support the weight of the unit. An inadequate
base or incomplete installation may cause injury or property damage in the event the unit falls o󰀨
of the base.
5. Electrical work shall be carried out in accordance with the installation manual and local, state
and National Electric Code (NEC). Insu󰀩cient capacity or incomplete electrical work may cause
electrical shock or re.
6. Be sure to use a dedicated power circuit. Never use a power supply shared by another appliance.
7. For wiring, use a cable that is long enough to cover the entire distance without a splice. Do not
use an extension cord. Do not put other loads on the power supply, use a dedicated power circuit.
(Failure to do so may cause abnormal heat, electric shock or re.)
8. Use the specied types of wires for electrical connections between the indoor and outdoor units.
Firmly clamp the interconnecting wires so their terminals receive no external stresses. Incomplete
connections or clamping may cause terminal overheating or re.
9. After connecting the interconnecting and supply wiring, be sure to shape the cables so that they
do not put undue force on the electrical covers or panels. Install covers over the wires. Incomplete
cover installation may cause terminal overheating, electrical shock or re.
10. If any refrigerant has leaked out during the installation work, ventilate the room. (The refrigerant
produces a toxic gas if exposed to ames.)
11. When installing or relocating the system, be sure to keep the refrigerant circuit free from
substances other than the specied refrigerant (R410-A), such as air. (Any presence of air or
other foreign substance in the refrigerant circuit can cause an abnormal pressure rise or rupture,
resulting in injury.)

Pre-Installation Checklist
1. Unpack and inspect each unit.
2. Check for any damage to the unit.
3. Check the model numbers to ensure a proper match.
4. Check the unit nameplate to ensure the proper electrical requirements will be met.
5. Check the installation locations to ensure the weight of the units can be supported.
6. Check the line set size requirements to ensure the correct refrigerant lines have been run
prior to connection.
7. Check the electrical line requirements to ensure the proper wiring has been run prior to
connection.
8. Check the indoor unit for coil leakage. The pressure relief valve on the gas line should
release pressurized nitrogen which ensures the unit has not leaked during shipping.
6
Cassette Unit
12. During pump-down, stop the compressor before removing the refrigerant piping. If the compressor
is still running and the stop valve is open during pump-down, air will be sucked in when the
refrigerant piping is removed, causing abnormal pressure in the refrigerant cycle which could lead
to breakage and injury.
13. During installation, attach the refrigerant piping securely before running the compressor. If the
compressor is not attached and the stop valve is open during pump-down, air will be sucked in
when the compressor is run, causing abnormal pressure in the refrigerant cycle which could lead
to breakage and injury.
14. Be sure to establish a ground. Do not ground the unit to a utility pipe, arrester, or telephone
ground. Incomplete ground may cause electrical shock, or re. A high surge current from lightning
or other sources may cause damage to the air conditioner.
15. If the supply cord is damaged, it must be replaced by the manufacturer, its service agent or
similarly qualied persons in order to avoid risk of electrical shock or re during and after
replacement.
CAUTION
1. Do not install the air conditioner in a place where there is danger of exposure to ammable gas
leakage. If gas leaks and builds up around the unit, it may result in re.
2. After all installation is complete, check to make sure that there is no refrigerant leakage.
3. This appliance is not intended for use by persons with a lack of experience and knowledge, unless
they have been given supervision or instruction concerning use of the appliance by a person
responsible for their safety.
4. Children should be supervised to ensure that they do not play with the appliance.
NOTICE
1. Establish drain piping according to the instructions in this manual. Inadequate piping may cause
ooding.
2. Tighten the are nut according to the specied method such as with a torque wrench. If the are
nut is tightened too hard, the are nut may crack and cause refrigerant leakage.

7
Cassette Unit
Clearance Requirements
NOTE: The minimum distance from the oor to the bottom of the unit is 71 inches (1.8m).
The maximum distance from the oor to the bottom of the unit is 13 feet (4m) for adequate
comfort control.
4MXC8524B10N
Model H
260 mm
＞20 mm
Wall
surface
Wall
surface
Wall
surface
Ground
surface
H
10.2 inch
mm0081>
>59 inch
>1500 mm
>59 inch
hcni17>
>1500 mm
0.8 inch
＞
4MXC8518B10N
4MXC8512B10N
Cassette Components
Air outlet vent
Air filter
(in air inlet grille)
Air inlet grille
Guide louver
(placed in air
outlet vent)
Internal condensate pump
Connecting pipe
Drainage hose

Refrigerant Piping Precautions
Nitrogen Purging While Brazing
WARNING
Hazard of Explosion and Deadly Gases!
Failure to follow all proper safe refrigerant handling practices could result in death or
serious injury. Never solder, braze or weld on refrigerant lines or any unit components
that are above atmospheric pressure or where refrigerant may be present. Always
remove refrigerant by following the guidelines established by the EPA Federal Clean
Air Act or other state or local codes as appropriate. After refrigerant removal, use dry
nitrogen to bring system back to atmospheric pressure before opening system for
repairs. Mixtures of refrigerants and air under pressure may become combustible in the
presence of an ignition source leading to an explosion. Excessive heat from soldering,
brazing or welding with refrigerant vapors present can form highly toxic gases and
extremely corrosive acids.
NOTICE
System Component Damage!
Do not remove the seal caps from the refrigerant connections and piping until prepared
to braze refrigerant lines to the connections. Excessive exposure to atmosphere (>5
min.) may allow moisture or dirt to contaminate the system, damaging valve seals and
causing ice formation in the system components during operation.
Nitrogen purging while brazing refrigerant pipes
Flow meter
Pressure regulator
Stop valve
Nitrogen
Nitrogen
NOTICE
Avoid Unit Damage!
Never braze pipe connections without performing nitrogen purging. Failure to perform
this procedure will damage the unit, resulting in capacity loss and reduced long-term
reliability.
While brazing refrigerant pipes, continuously purge them with nitrogen gas. Use a
pressure regulator to maintain a ow rate of 0.03 CFM (0.05 m³/h) or more.
8
Cassette Unit

WARNING
Adequate Support Required!
The wall/ceiling structure must be adequate to support 4 times the weight of the unit.
Failure to ensure adequate structural support could result in the unit falling from its
location which could result in death, serious injury, or equipment or property-only damage.
9
Cassette Unit
1. Avoid locating the indoor unit where the return and/or supply air may be obstructed.
2. Select an installation location where it is easy to drain the condensing water from
the indoor unit and where it will be easy to route refrigerant lines and communication
cabling to the outdoor unit.
3. Keep the indoor unit far away from heat sources, vapor and ammable gas.
4. It is not recommended that this unit be installed in or near a kitchen environment.
If adequate distance from the kitchen cannot be achieved, the kitchen must have
adequate ventilation to prevent contamination of the units external and internal working
parts.
5. Be sure that the installation of the indoor unit conforms to the installation dimension
diagram.
6. Ensure the installation is horizontally level.
7. Be sure to leave enough space to allow access for routine maintenance; clearance
between the bottom of the indoor unit and the oor should not be less than 71 inches.
8. Install in a location where the unit is more than 3 feet away from other electronic
appliances that could cause interferance such as television, audio devices, etc.
9. Select a location where air lters can be easily removed and replaced.
10.When installing the threaded rod or bolt, check if the installation location can withstand
4 times the weight of the units. If not, reinforce before installation. (Refer to the
installation template and locate where it should be reinforced)
Installation Location
Indoor Unit
For instructions on installing the outdoor unit please refer to the installation guide
supplied with the selected outdoor unit for your application.

Installing the Indoor Unit
10
Cassette Unit
WARNING
Hazardous Service Procedures!
The maintenance and troubleshooting procedures recommended in this section of the
manual could result in exposure to electrical, mechanical or other potential safety
hazards. Always refer to the safety warnings provided throughout this manual
concerning these procedures. Disconnect all electrical power including remote disconnect and
discharge all energy storing devices such as capacitors before
servicing. Follow proper lockout/tagout procedures to ensure the power can not be
inadvertently energized. When necessary to work with live electrical components, have
a qualied licensed electrician or other individual who has been trained in handling live
electrical components perform these tasks. Failure to follow all of the recommended
safety warnings provided, could result in death or serious injury.
Mounting Location
1. Conrm the mounting location with the customer. Keep in mind the guidelines for a safe
installation location on page 8.
2. The drilling of holes in the ceiling must be done by the installing technician.
3. The dimensions for the ceiling openings can be as large as 35.8 inches (190mm). The
panel should overlap the ceiling by no less than 0.8 inches (20mm).
4. Ensure the hanging point is strong enough to support 4 times the weight of the unit.
5. The weight of the unit should be shared equally by the expansion bolts.
6. Insert the M10 (or larger) expansion bolts into the hole and knock the nail into the bolt. Refer
to the outline dimension drawings for the distance between holes.
7. Install the indoor unit by inserting the bolts through the hanging brackets as shown below.
Installation brackets for main body of the unit
6.3in
160mm
Minimum 0.8in / 20 mm
Minimum

• If there is an opening in the ceiling, it should be reinforced to keep it at and prevent vibration.
• If the support structure of the ceiling is not strong enough, a beam made of angle iron can be
used to mount the unit to for added support.
• If the indoor unit is not installed in an air conditioned area, please insulate around the unit
to prevent condensation. The thickness of the insulation depends on the actual installation
environment.
11
Cassette Unit
Unit: Inch (mm)
For the units: 12-18k
For the units: 24k
H
H
Fig.3
Item A
Model BCDEFGH
12K
18K
24K
26-3/8
(670)
26-1/4
(666)
23-5/8
(600)
19-1/2
(495)
5-11/16
(145)
9-7/16
(240)
22-7/16
(570)
22-7/16
(570)
37-3/8
(950)
26-3/4
(680)
9-7/16
(240)
5-11/16
(145)
26-3/4
(680)
30-11/16
(780)
33-1/16
(840)
30-11/16
(780)
Dimension of Ceiling Opening and Location of the Expansion Bolts (M10)

1. Use a hoisting stand to aid in lifting and securing the unit.
2. To attach the hoisting stand, use a nut and gasket at the upper and lower section of the
hoisting stand to secure it. The use of a washer anchor board can prevent the washer from
breaking o󰀨.
3. Use the enclosed installation template.
4. Please refer to the installation template to verify the dimensions of the ceiling opening.
5. The central mark of the ceiling opening is marked on the installation template.
6. Attach the installation template to the unit using screws, and x the angle of the drainage pipe
at the outlet vent with a bolt.
7. Adjust the unit to align with the ceiling.
8. Check to ensure the unit is horizontal.
9. The inner drainage pump and oat switch are included in the indoor unit, check the four
corners of the unit to ensure they are level. If the unit is slanted toward the opposite side of
the drain pan from the oat switch, there may be a malfunction of the oat switch that may lead
to overowing condensation.
10.Remove the washer anchor board used to prevent a washer break o󰀨 and tignten the nut.
11. Remove the installation template.
12.Tighten the nuts to prevent the unit from falling.
Nut(supplied at site)
Washer(attachment)
Washer anchor board (attachment)
Bolt(attachment)
Bolt(attachment)
Water level
Polyethylene pipe
Center of the ceiling
opening
Insert
Installation template
Hoisting stand
Tighten(double nuts)
[Fix the hoisting stand firmly] [Fix the washer firmly]
[Fix the installation template]
One bolt must be in this location
12
Cassette Unit
Hoisting the Main Body of the Unit

Installation of the Condensate Pipe
Design of the Condensate Pipe
1. The drain pipe should maintain a downward slope of 1/50 to avoid water accumulation or
improper drainage which could lead to equipment and/or property damage.
2. When connecting the drain pipe to the unit, avoid excessive force on the connection. The pipe
should be as close to the unit as possible.
3. The drain pipe can be ordinary hard PVC pipe which can be purchased locally. During the
connection, insert the end of the PVC pipe to the drain outlet, then tighten it to the drain hose
with a hose clamp. Do not connect the drain outlet and the drain hose with an adhesive.
4. When the drain pipe is used for multiple units, the joined section of the pipe should be 3.9
inches (100mm) lower than the drain hole of each device and it is suggested to use a larger
diameter pipe when connecting multiple units.
Installation of the Condensate Pipe
1. The diameter of the drain pipe should be greater than or equal to that of the refrigerant pipe.
(PVC pipe, outer diameter : 1 inch (25mm), wall thickness ≥0.05 inches (1.5mm).
2. The drain pipe should be as short as possible and with at least a 1/50 slope to avoid forming
air pockets.
3. If the proper degree of slope of the drain pipe is not feasible, a lift bracket should be installed.
4. A maximum distance of 60 inches (1.5m) must be maintained between supports to avoid the
drain hose sagging or bending.
40-60 in
1-1.5m
(Correct) 1/50 degree slope or greater (Wrong)
5. Insert the drain hose into the drain hole and tighten it with clamps.
6. Insert the drain pipe into the opposite end of the drain hose and clamp securely. Do not use
adhesive at this joint.
7. Wrap the clamps with a large amount of foam wrap for thermal insulation to prevent
condensation and water damage.
Clamp (accessory)
Foam wrap (gray) Drain Hose
Foam wrap (accessory)
Clamp
(accessory)
Max. 4mm
0.16 inch
13
Cassette Unit

Insulating Layer for the Condensate Pipe
Pipe Lip
Thermal Insulation of the Condensate Pipe
CAUTION
Seal properly and verify there is no water leakage from the joint of the condensate pipe.
Failure to do so may result in equipment and/or property damage.
Be sure to secure with a clamp and insulate completely to avoid condensate build-up.
Insulation of the Condensate Pipe
Precautions for the Drain Pipe
The installed height of the lift pipe should be less than 11 inches (280mm). It is recommended to
set an inclination angle of 1~2° for the lift pipe toward the drainage direction. If the lift pipe and
the unit form a right angle, the lift pipe must be less than 11.8 inches (300mm) from the unit.
Drain hose(attachment)
Within / 11.8 in300mm
Roof
Drain raising hose
220 mm/8.6 in
39.4-59in
1-1.5m Hoisting stand
Less than 11in(280mm)
Below 19.7in
500mm
Ceiling Clamp(attachment)
14
Cassette Unit

NOTES:
1. The connection height of the drain hose should be within 3 inches (7.5mm) so that the outlet of
the drain hose does not su󰀨er from external force.
2. If multiple drain pipes converge, please follow the installation diagrams below.
Test the Drainage System
After the electrical installation, test the drainage system.
1. Turn on power to the system to allow the drain pump to operate.
2. Use a squeezable wash bottle with a spout longer than 3.9 inches (100mm) to squirt water into
the drain pan. Water can be introduced into the drain pan by 2 methods shown below, depending
on the model of cassette.
3. During the test, check to ensure the water ow goes through the pipe correctly and observe
the joint carefully to see if it leaks. If this unit is installed in a newly built house, it is suggested to
perform this test prior to the ceiling installation.
Drain hose(attachment)
Below 19.7in
500mm
Below
3 in
75mm
Above 3.9in(100mm)T-tie in joined drain hose
The specs of the selected joined drain hose should fits the running capacity of the unit
More than 100mm
Drain hose Test hole cover
Test hole
Adding water from the test hole
Adding water from the outlet vent terminal
Plastic wash bottle (The length of
the pipe should be more than 3.9 inch (100mm)
Drain vent for repair use
(plastic stopper is included)
More than 3.9 inch
Note: This drawing represents several models of cassettes. On some models, the test hole
option will be unavailable.
15
Cassette Unit

In. (mm) Tightening Torque
1/4 (6.35) 15 ~ 30 N•m / 20.3-40.7 (ft-lbf)
3/8 (9.52) 35 ~ 40 N•m / 40.7-54.2 (ft-lbf)
1/2 (12.7) 45 ~ 50 N•m / 61.0-67.8 (ft-lbf)
5/8 (15.9) 60 ~ 65 N•m / 81.3-88.1 (ft-lbf)
3/4 (19.05) 70 ~ 75 N•m / 94.9-101.7 (ft-lbf)
16
Cassette Unit
Connecting the Pipe at the Indoor Unit
Remove the caps and plugs from the pipes.
NOTICE
1. Be sure to connect the pipe to the port on the indoor unit correctly. If the centering is
improper, the are nut cannot be tightened smoothly. If the are nut is forced to turn, the
threads will be damaged.
2. Do not remove the are nut until the connection pipe is to be connected so as to prevent dust
and impurities from coming into the pipe system.
Back-up Wrench
1. When connecting the pipe to the unit or removing it from the unit, please use both a torque
wrench and a back-up wrench. See illustration below.
2. When connecting, smear both inside and outside of the are nut with refrigeration oil, tighten it
by hand and then tighten it with the spanner.
3. Refer to the table below before tightening to determine the appropriate torque (too tight would
damage the nut and lead to refrigerant leakage).
4. Examine the connection pipe to see if it leaks, then apply thermal insulation for the liquid and
gas lines, as shown below.
5. Use medium-sized sponge wrap to insulate the coupler of the gas pipe and secure with tape.

CAUTION
1. During the connection of the indoor unit and the refrigerant pipe, never pull any parts of the
indoor unit forcefully: otherwise the refrigerant pipes or other pipes may crack, which would
then result in leakage.
2. The refrigerant piping should be supported by brackets. Unsupported piping will put stress on
the indoor unit and could lead to leaking or breakage.
If the specication of the outdoor unit pipe joint does not conform to that of the indoor unit, then
the joint specication of the outlet pipe of the indoor unit takes precedence. A reducing transition
shall be installed at the connection point of the outdoor unit so as to make the connection of the
outdoor unit compatible with that of the indoor unit.
Installing the Refrigerant Piping
Flaring Process
1. Hold the pipe downward to prevent cuttings from entering the pipe.
2. Cut the refrigerant pipe with the pipe cutter and remove the burrs.
3. Remove the are nuts at the stop valve of the outdoor unit and inside the accessory bag of
the indoor unit, put them onto the refrigerant pipe as shown below then are the refrigerant
pipe with a aring tool.
4. Check if the are part is spread evenly and there are no cracks.
Item
Model
Size of Fitting Pipe
Inch (mm) Max. Pipe
Length
ft (m)
Max. Height Di󰀨erence
between Indoor Unit
and Outdoor unit
ft (m)
Drainage pipe
(Outer Diameter
x wall thickness)
Inch (mm)
Liquid Gas
12K
1/4
(6.35)
3/8
(9.53)
65-5/8
(20)
49-1/4
(15)
Ø 1 x 1/16
(Ø 25 x 1.5)
18K 1/2
(12.70)
65-5/8
(20)
49-1/4
(15)
24K 3/8
(9.53)
5/8"
(15.88)
98-7/16
(30)
49-1/4
(15)
17
Cassette Unit

NOTICE
1. To prevent distortion and breaking of the pipe, avoid sharp bends. Bend the pipe with a
radius of curvature of 6 in. (150 mm) or more.
2. If the pipe is bent repeatedly at the same place, it will break.
CAUTION
Be sure to connect the gas pipe after connecting the liquid pipe completely.
Connecting the Pipe at the Outdoor Units
Tighten the are nut of the connection pipe at the outdoor unit valve connector. The tightening
method is the same as the method at the indoor unit.
Bending Pipes
1. The pipes should be shaped by your hands or a refrigerant pipe bending tool for tighter bends.
Be careful not to collapse them.
2. Do not bend the pipes in an angle more than 90°
3. When pipes are repeatedly bent or stretched, the material will be prone to damage, which may
lead to refrigerant leaks. Do not bend or stretch the pipes more than three times.
4. Do not bend the pipe while it is encased in the insulation. In this case, cut the insulation with a
sharp cutting tool as shown below, and bend it after exposing the pipe. After bending the pipe
as you want, be sure to put the insulation back on the pipe, and secure it with tape.
18
Cassette Unit

Insulation of the Pipe Joints
1. The refrigerant pipe should be insulated with appropriate insulating material and
plastic tape in order to prevent condensation and water leakage.
2. The joints of the indoor unit should be wrapped with insulating material. No gap is
allowed on the joint of the indoor unit, as shown below.
WARNING
1. If the power cord or the communication line are damaged, they must be replaced with the
required replacement part.
2. Prior to wiring, please check the electrical information marked on the nameplate and carry
out the wiring following the wiring diagram.
3. The air conditioning unit must be grounded to prevent electrical shock hazards.
4. All wiring should be done strictly in accordance with the wiring diagram. Improper wiring
would cause abnormal operation or damage to the unit.
5. Do not let the electrical wires touch the refrigerant pipe, the compressor, the fan or other
moving parts.
6. Do not modify the wiring inside the indoor unit, otherwise the manufacturer will not assume
any responsibility for damage or abnormal operation of the unit.
Wiring the Indoor Unit
1. Open and remove the cover of the electrical box of the indoor unit.
2. Insert the power cord through the rubber ring.
3. Pull the 4-wire cable through the wiring hole of the chassis upward, then connect the power
line and the communication line from the outdoor unit to the corresponding terminals N(1), 2,
3 and grounding terminal of the indoor unit. Wiring shall be done properly as per the wiring
diagram. (NOTE: Be sure the wiring terminals A/B/C/D/E and piping ports A/B/C/D/E of the
indoor unit match with that of the outdoor unit respectively).
19
Cassette Unit

To indoor unit
To outdoor unit Impact fastener
Electrical box cover (1)
Electrical hole
Electrical hole
Seal here to prevent
water leakage
Electrical box cover (2)
Power supply 3 way
terminal board
Example: Wiring Connection for 4TXM6542A1050
POWER
INDOOR UNIT AINDOOR UNIT BINDOOR UNIT CINDOOR UNIT D
OUTDOOR UNI
T
INDOOR UNIT E
XT2
XT1
XT3
XT4
XT5
XT6
N
L
G
G
G
G
G
NOTE: The wiring diagrams in this
guide are included as a reference.
The manufacturer has a policy of
continuous product and product data
improvement and reserves the right
to change design and specications
without notice. Always check the unit
nameplate and wiring diagram for the
actual unit requirements.
Note: Ground must be wired from
the outdoor unit. If the indoor unit
is grounded locally, communication
errors will occur.
20
Cassette Unit