Mitsubishi Electric Msz-gs18na-u1 Premier Wall Mounted Indoor Unit Instruction Manual

• Depending on the installation area, install a Ground Fault
  Interrupt (GFI) circuit breaker to ensure safety during
  operation.

ENGLISH

SPLIT-TYPE AIR CONDITIONERS
INSTALLATION MANUAL

MSZ-GS18NA MSY-GS18NA

JG79N458H01

When installing multi units, refer to the installation manual of the multi unit for outdoor unit installation.

Required Tools for Installation

Phillips screwdriver Level Scale Utility knife or scissors 3 in. (75 mm) hole saw Torque wrench Wrench (or spanner)

5/32 in. (4 mm) hexagonal wrench Flare tool for R410A Gauge manifold for R410A Vacuum pump for R410A Charge hose for R410A Pipe cutter with reamer

1. BEFORE INSTALLATION

1-1. THE FOLLOWING SHOULD ALWAYS BE OBSERVED FOR SAFETY
· Be sure to read these safety precautions and instructions. · Be sure to observe the warnings and cautions speci ed here. · After reading this manual, be sure to store it with the OPERATING INSTRUCTIONS for future reference. · Please report to your supply authority or obtain their consent before connecting this equipment to the power supply system.

WARNING (Could lead to death or serious injury.)

Do not install the unit by yourself (user). Improper or incomplete installation could cause re, electric shock, injury due to the unit falling, or water leakage. Consult a quali ed installer or the dealer from whom you purchased the unit.
Follow the instructions detailed in the installation manual. Incomplete installation could cause re or electric shock, injury due to the unit falling, or leakage of water.
When installing the unit, use appropriate protective equipment and tools for safety.
Failure to do so could cause injury. Install the unit securely in a place that can bear the weight of the unit.
If the installation location cannot bear the weight of the unit, the unit could fall causing injury. Do not alter the unit. It may cause re, electric shock, injury or water leakage. Perform electrical work according to the installation manual and be sure to use an exclusive circuit. Do not connect other electrical appliances to the circuit.
If the capacity of the power circuit is insuf cient or there is incomplete electrical work, it could result in a re or an electric shock. Ground the unit correctly. Do not connect the ground wire to a gas pipe, water pipe, lightning rod or telephone ground. Defective grounding could cause electric shock. Do not damage the wires. Damaged wires could cause re. Be sure to shut off the main power when setting up the indoor P.C. board or wiring.
Failure to do so could cause electric shock. 8VHWKHVSHFL¿HGZLUHVWRVHFXUHOFRQQHFWWKHLQGRRUDQGRXWGRRUXQLWV$W-
WDFKWKHZLUHV¿UPOWRDYRLGDSSOLQJVWUHVVWRWKHWHUPLQDOEORFN Improper connection could cause re. ‘RQRWLQVWDOOWKHXQLWLQDSODFHZKHUHÀDPPDEOHJDVPDOHDN If gas leaks and accumulates around the unit, it could cause an explosion. Do not use intermediate connection of the power cord or the extension cord. Do not connect many devices to one AC outlet.
It could cause a re or an electric shock. 8VHWKHSDUWVSURYLGHGRUVSHFL¿HGSDUWVIRUWKHLQVWDOODWLRQZRUN
The use of defective parts could cause an injury or leakage of water due to a re, an electric shock, the unit falling, etc. When plugging the power supply plug into the outlet, make sure that there is no dust, blockage, or loose parts both in the outlet and on the plug. Verify that
the power supply plug is completely in the outlet.
If there is dust, blockage, or loose parts on the power supply plug or the outlet, it could cause electric shock or re. If loose parts are found on the power supply plug, replace it.

Securely attach the electrical cover to the indoor unit and the service panel to the outdoor unit.
If the electrical cover of the indoor unit and/or the service panel of the outdoor unit are not attached securely, dust, water, etc. could collect in the unit and could cause a re or an electric shock. When installing, relocating, or servicing the unit, make sure that no substance RWKHUWKDQWKHVSHFL¿HGUHIULJHUDQW5$HQWHUVWKHUHIULJHUDQWFLUFXLW Any presence of foreign substance such as air can cause abnormal pressure rise and may result in explosion or injury. The use of any refrigerant other than that speci ed for the system will cause mechanical failure, system malfunction, or unit breakdown. In the worst case, this could lead to a serious impediment to securing product safety. Do not discharge the refrigerant into the atmosphere. Check that the refrigerant gas does not leak after installation has been completed. If refrigerant leaks
during installation, ventilate the room.
If refrigerant comes in contact with a re, harmful gas could be generated. If refrigerant gas leaks indoors, and comes into contact with the ame of a fan heater, space heater, stove, etc., harmful gases will be generated. Use appropriate tools and piping materials for installation. The pressure of R410A is 1.6 times higher than R22. Not using the appropriate tools and materials, or improper installation could cause the pipes to burst causing an injury. When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes.
If the refrigerant pipes are disconnected while the compressor is running and the stop valve is open, air could be drawn in and the pressure in the refrigeration cycle could become abnormally high, causing the pipes to burst. When installing the unit, securely connect the refrigerant pipes before starting the compressor.
If the compressor is started before the refrigerant pipes are connected and the stop valve is open, air could be drawn in and the pressure in the refrigeration cycle could become abnormally high, causing the pipes to burst. )DVWHQDÀDUHQXWZLWKDWRUTXHZUHQFKDVVSHFL¿HGLQWKLVPDQXDO If fastened too tight, a are nut could break and cause refrigerant leakage. Install the unit according to national wiring regulations. When opening or closing the valve below freezing temperatures, refrigerant may spurt out from the gap between the valve stem and the valve body, resulting in
injuries.

CAUTION (Could lead to serious injury when operated incorrectly.)

Depending on the installation area, install a Ground Fault Interrupt (GFI) circuit breaker.
If the Ground Fault Interrupt (GFI) circuit breaker is not installed, an electric shock could occur. Perform the drainage/piping work securely according to the installation manual. If there is defect in the drainage/piping work, water could drip from the unit, and damage household items. ‘RQRWWRXFKWKHDLULQOHWRUWKHDOXPLQXP¿QVRIWKHRXWGRRUXQLW

This could cause injury. Do not install the outdoor unit where small animals may live.
If small animals enter the unit and damage its electrical parts, it could cause a malfunction, smoke emission, or re. Keep the area around the unit clean.

1-2. SELECTING THE INSTALLATION LOCATION

INDOOR UNIT

Note:

Note:

· Where air ow is not blocked.

In rooms where inverter type uorescent lamps are used, · It is advisable to make a piping loop near outdoor unit

· Where cool air spreads over the entire room.

the signal from the wireless remote controller may not be so as to reduce vibration.

· On a rigid wall to reduce the possibility of vibration.

received.

· For increased ef ciency, install the outdoor unit in a

· Where it is not exposed to direct sunlight. Do not ex-

location where continuous direct sunlight or excessive

pose to direct sunlight also during the period following OUTDOOR UNIT

water can be avoided as much as possible.

unpacking to before use.

· Where it is not overly exposed to strong winds.

· Where it can be easily drained.

· Where air ow is good and dustless.

· At a distance 3 ft. (1 m) or more away from a TV and · Where neighbours are not annoyed by operation Note:

radio. Operation of the air conditioner may interfere sound or hot air.

When operating the air conditioner in low outside tem-

with radio or TV reception. An amplifier may be re- · Where rigid wall or support is available to prevent the perature, be sure to follow the instructions described

quired for the affected device.

increase of operation sound or vibration.

below.

· In a place as far away as possible from fluorescent · Where there is no risk of combustible gas leakage.

· Never install the outdoor unit in a place where its air

and incandescent lights. In order to make the infrared · If installing the unit in a location high above the ground,

inlet/outlet side may be exposed directly to wind.

remote control operate the air conditioner normally. be sure to secure the unit legs.

· To prevent exposure to wind, install the outdoor

The heat from the lights may cause deformation or the · Where it is at least 10 ft. (3 m) away from the antenna

unit with its air inlet side facing the wall and a baf e

ultraviolet may cause deterioration.

of TV set or radio. Operation of the air conditioner may

board on the air outlet side.

· Where the air lter can be removed and replaced easily. interfere with radio or TV reception in areas where re- Avoid the following places for installation where air

· Where it is away from the other heat or steam source.

ception is weak. An ampli er may be required for the conditioner trouble is liable to occur.

Note:

affected device.

· Where ammable gas could leak.

Install the indoor unit high on the wall where air can dis- · Install the unit horizontally.

· Where there is an excessive amount of machine oil

tribute over the entire room.

· Please install it in an area not affected by snowfall or

in the air.

blowing snow. In areas with heavy snow, please install · Where oil is splashed or where the area is lled with

REMOTE CONTROLLER

a canopy, a pedestal and/or baf e boards.

oily smoke (such as cooking areas and factories,

· Where it is convenient to operate and easily visible. · Where children cannot easily touch it. · Select a position about 4 ft. (1.2 m) above the oor.
Check that signals from the remote controller from that position are received by the indoor unit (`beep’ or `beep beep’ receiving tone sounds). Then, attach remote controller holder to a pillar or wall and install wireless remote controller.

in which the properties of plastic could be changed and damaged). · Salty places such as the seaside. · Where sul de gas is generated such as hot spring, sewage, waste water. · Where there is high-frequency or wireless equipment. · Where there is emission of high levels of VOCs, including phthalate compounds, formaldehyde, etc., which may cause chemical cracking.

1-3. SPECIFICATIONS
1-3-1. POWER SUPPLY AND INDOOR/OUTDOOR
WIRE CONNECTION
· Power should be taken from an exclusive branched circuit. · Wiring work should be based on applicable technical stand-
ards. · Wiring connections should be made following the diagram. · Securely tighten screws.

Connecting wires and the ground wire
· Use solid conductor Min. AWG14 or stranded conductor Min. AWG14.
· Use double insulated copper wire with 600 V insulation. · Use copper conductors only. * Follow local electrical codes. Power supply cable and ground wire
· Use solid or stranded conductor.

MUZ-GS18NA(H) MUY-GS18NA
MUZ-GS18NAHZ

Min. AWG14 Min. AWG12

· Use copper conductors only. * Follow local electrical codes.

Note:
When the indoor unit is powered from the outdoor unit, depending on local code, a disconnect switch needs to be installed to a power supply circuit.

(OHFWULFDOVSHFL¿FDWLRQV

MODEL

INDOOR OUTDOOR

INDOOR UNIT

Power supply (V, PHASE, Hz)

Min. Circuit Ampacity

(A)

Fan motor (F.L.A.)

(A)

OUTDOOR UNIT

Power supply (V, PHASE, Hz)

Max. Fuse size (time delay) (A)

Min. Circuit Ampacity

(A)

Fan motor (F.L.A.)

(A)

Compressor

(R.L.A) (A) (L.R.A) (A)

MSZ MSY MSZ MSY

Control voltage

MSZ-GS18NA MSY-GS18NA

MUZ-GS18NA(H) MUY-GS18NA

MUZ-GS18NAHZ

208/230, 1, 60 1.0 0.74

208/230, 1, 60

15

20

12

18

0.93

0.93

8.4

13.6

8.4

–

10.5

17.0

10.5

–

Indoor unit – Remote controller: (Wireless) Indoor unit – Outdoor unit: DC12-24 V (Polar)

1-3-2. REFRIGERANT PIPES
· To prevent condensation, insulate the two refrigerant pipes.
CAUTION Be sure to use the insulation of speci ed thickness (table on the right). Excessive insulation may cause incorrect installation of the indoor unit, and too little insulation may cause condensate to form.
· Refrigerant pipe bending radius must be 4 in. (100 mm) or more.
· The unit has ared connections on both indoor and outdoor sides.
· Remove the valve cover from the outdoor unit, then connect the pipe.
· Refrigerant pipes are used to connect the indoor and outdoor units.
· Be careful not to crush or over bend the pipe in pipe bending. · Refrigerant adjustment… If pipe length exceeds 25 ft. (7.5 m),
additional refrigerant (R410A) charge is required. (The outdoor unit is charged with refrigerant for pipe length up to 25 ft. [7.5 m]) · Please carefully consider the indoor unit location when piping lengths are less than 16 ft. (5 m) as there could be intermittent noises during normal operation that would be noticeable in very quiet environments.

Pipe For liquid For gas

Outside diameter
1/4 (6.35) 3/8 (9.52) 1/2 (12.7)

Minimum wall thickness inch (mm)
0.0315 (0.8) 0.0315 (0.8) 0.0315 (0.8)

Insulation thickness
5/16 (8) 5/16 (8) 5/16 (8)

Insulation material
Heat resistant foam plastic 0.045 Speci c gravity

Pipe length Height difference No. of bends

MSZ/MSY-GS18NA MSZ/MSY-GS18NA

Limits

100 ft. (30 m) max. 50 ft. (15 m) max.
10 max.

Pipe length Refrigerant to be added

Up to 25 ft. (7.5 m) Exceeding 25 ft. (7.5 m)
MSZ/MSY-GS18NA

No additional charge is required. Additional charge is required. (Refer to the table below.) 1.08 oz each 5 ft. (20 g/m)

1-4. INSTALLATION DIAGRAM
ACCESSORIES Check the following parts before installation. <Indoor unit>

(1) Installation plate

1

Attachment screws for the installa-

(2) tion plate

5

4 × 25 mm

(3) Wireless remote controller

1

(4) Felt tape (For left or left-rear piping)

1

(5) Remote controller holder

1

Screws for the remote controller

(6) holder

2

3.5 × 16 mm (Black)

(7) Battery (AAA) for (3)

2

(8) Air cleaning lter

2

FIELD-SUPPLIED PARTS

(A) Indoor/outdoor unit connecting wire*1

(B) Extension pipe

(C) Wall hole sleeve

(D) Wall hole cover

(E) Pipe attachment strap

(F) Screw for (E) 4 × 20 mm

(G) Piping tape

(H) Putty

Drain hose

(I)

(or soft PVC hose, 19/32 in. [15 mm] inner diameter or hard PVC pipe

VP16)

(J) Refrigerant oil

(K) Power supply cord *1

1 1 1 1 2 to 5 2 to 5 1 1
2 to 5
1 1

Note:
*1 Place indoor/outdoor unit connecting wire (A) and power supply cord (K) at least 3 ft. (1 m) away from the TV antenna wire.

4 3/8 in. (111 mm) or more / 5 3/16 in. (132 mm) or more for left and left back piping (using spacer)

(o15r3m13/o4mriemn.)

Use the wall hole sleeve (C) to prevent indoor/outdoor connecting wire (A) from contacting metal parts in the wall and to protect the wiring from rodents.

Indoor unit
Wall hole sleeve (C)

Cut off the extra length.

(o16r65m8/8omrimen.)

Wall hole cover (D)
Seal the wall hole gap with putty (H).
Attach the pipe to wall with pipe attachment strap (E).
Pipe attachment strap (E)
Attachment screw (F)

After the leak test, apply insulating material tightly so that there is no gap.

3/8 in. (10 mm) or more

5.9 ft. to 7.5 ft. (1.8 m to 2.3 m) from the oor is recommended

*2 20 in. (500 mm) or more when front and sides of unit are clear

4

in. or

(m10o0remm)

4 in.o(r1m00ormem)

When the piping is to be attached to a wall comprised of tin plate or metal netting, use chemically treated wooden piece 25/32 in. (20 mm) or thicker between the wall and the piping, or wrap insulation vinyl tape 7 to 8 turns around the piping. To use existing piping, perform COOL operation for 30 minutes and pump down before removing the old air conditioner. Remake are according to the dimension for new refrigerant.

6-7/8

33-1/16 19-11/16
Air inlet

Unit: inch

clear *2 15-3/8
13 Air inlet

14-3/4~14-5/8

20 in. (o5r0m0omrem) *3

14

in. or

m(3o5r0emm)

*3 When any 2 sides of left, right and rear of unit are clear

Air outlet

2-3/8 x 13/16 slot

1-18/32

840

175

500

Air inlet

Unit: mm

349~371

390 330 Air inlet

Units should be installed by licensed contractor according to local code requirements.

Air outlet

2-10 x 21 slot

40

Note:
· The dimensions indicated in the arrows ( ) above show the required space to guarantee performance of the air conditioner. Install the outdoor unit where the maximum possible space can be provided, considering later relocation, services, or repairs.
· The cooling/heating performance and the ef ciency of power usage may fall about 10% at the place where short cycle is likely occur due to poor ventilation. Installing the air outlet guide (optional) can improve performances.
· If air from the outlet blows against the wall, it may cause stains on the wall.

Do not take in the outlet air discharged by other units directly.

1(54-030/4minm. oorrmmoorree) 3(91-030/80inm.moromr omroere)

Drain piping for outdoor unit
Install the unit horizontally. Do not use drain socket in cold regions. Drain may freeze and make the fan stop. The outdoor unit produces condensate during the heating operation. Select the installation place to ensure to prevent the outdoor unit and/or the grounds from being wet by drain water or damaged by frozen drain water.

2. INDOOR UNIT INSTALLATION

2-1. ATTACHING THE INSTALLATION PLATE
· Find a stud in the wall to attach installation plate (1) horizontally by tightening the xing screws (2) rmly.
· To prevent installation plate (1) from vibrating, be sure to install the attachment screws in the holes indicated in the illustration. For added support, additional screws may also be installed in other holes.
· When the indoor unit is to be attached to a concrete wall using recessed bolts, secure installation plate (1) using 7/16 in. x 13/16 in. · 7/16 in. x 1 in. (11 mm × 20 mm · 11 mm × 26 mm) oval hole (17-3/4 in. [450 mm] pitch).
· If the recessed bolt is too long, change it for a shorter one ( eld-supplied).

Installation plate (1) 5 1/4 in. (133 mm) or more
Wall

Fixing screw (2)

2-2. DRILLING
1) Determine where the holes will be located on the wall. 2) Drill a ø 3 in. (75 mm) hole. The outdoor side should be 6/32 to 9/32 in. (5 to 7 mm)
lower than the indoor side. 3) Insert wall hole sleeve (C).

Ceiling Level

4 3/8 in. (111 mm) or more 5 3/16 in. (132 mm) or more for left and left back piping (using spacer)
6 5/8 in. (168 mm) or more 4 in. (100 mm)
Wall

Insert the scale. *

Align the scale with the line. *

Center of ø3 in.(ø75 mm) hole

* Same for left hole.

Ø 3 in. (75 mm)

Wall
6/32-9/32 in. (5-7 mm) Outdoor side

2-3. CONNECTING WIRES FOR INDOOR UNIT
Note:
When the indoor unit is powered from the outdoor unit, depending on local code, a disconnect switch needs to be installed to a power supply circuit.

Electrical cover

Electrical box

Grounding terminal

Terminal block Terminal block 2
Terminal block 1

1) Remove the panel assembly. (Refer to 5-1.) 2) Place the upper part of the indoor unit on the installation plate. 3) Remove corner box R and electrical cover. 4) Remove display panel, conduit cover and conduit plate. 5) Attach conduit pipe (for rear piping) / elbow joint (for right, left, or downward piping) to
conduit plate with lock nut. The thread of the installed conduit pipe / elbow joint appearing inside should be less than 3/8 in. (10 mm). (Fig. 1) Elbow joint should appear less than 1-3/16 in. (30 mm) outside. (Fig. 2) 6) Process the end of ground wire (Fig. 3). Connect it to the ground terminal of electrical parts box. 7) Process the end of indoor/outdoor unit connecting wire (A) (Fig. 3). Attach it to the terminal block. Be careful not to make mis-wiring. Attach the wire to the terminal block securely so that its core cannot be seen, and no external force affects the connecting section of the terminal block. 8) Firmly tighten the terminal screws. After tightening, verify that the wires are tightly fastened. 9) Reinstall conduit plate, conduit cover and display panel. 10) According to the piping direction, remove the shaded part of the corner box L (Fig. 4) or corner box R (Fig. 5). Reinstall electrical cover, corner box and front panel.

Remark: * A disconnect switch
should be required. Check the local code. ** Use a ring tongue terminal in order to connect a ground wire to terminal.
OUTDOOR UNIT <MUZ-GS18NA(H)>
<MUY-GS18NA>

INDOOR UNIT Terminal block
9$&, Grounding terminal** SKDVH+] OUTDOOR UNIT <MUZ-GS18NAHZ>
Ground Power supply 208/230 V AC, 1 phase 2 wires, 60 Hz

Grounding terminal**
Disconnect switch*

Fixing screw

Conduit cover Indoor control P.C. board holder

Indoor terminal block
Conduit pipe (for rear piping) or

Lock nut

Elbow joint (for right, left, or downward piping)

Conduit plate

Fixing screw

· Connect wires to the appropriate terminals · For future servicing, leave some slack in the connecting wires.

Conduit plate

Less than 3/8 in. (10 mm)
Lock nut Conduit pipe or elbow joint

Conduit plate

Less than 1-3/16 in. (30 mm)

Grounding terminal**

Fig. 1

Elbow joint (for right, left, or downward piping)
Fig. 2

19/32 in. (15 mm)

Corner box L

Corner box R

Lead wire
· Make ground wire a little longer than others. (More than 1-9/16 in. [40 mm]) Fig. 3

Remove corner box L for piping on bottom side of unit.

Remove corner box L for piping on left side of unit.

Fig. 4

Remove corner box R for piping on right side of unit.

Remove corner box R for piping on bottom side of unit.

Fig. 5

2-4. PIPE FORMING AND DRAIN PIPING
2-4-1. PIPE FORMING · Place the drain hose below the refrigerant piping. · Make sure that the drain hose is not crowded or bent. · Do not pull the hose when applying the tape. · When the drain hose passes the room, be sure to wrap it with insulation material
( eld-supplied). Note: Make sure not to damage the cover of refrigerant pipe when attaching it back on with screws.
Left or left-rear piping Note:
Be sure to reattach the drain hose and the drain cap if the piping is being installed on left or bottom left of unit, otherwise, water could drip down from the drain hose.
1)Place the refrigerant piping and the drain hose together, then rmly apply felt tape (4) from the end. Felt tape (4) overlap width should be 1/3 the tape width. Use a bandage stopper at the end of felt tape (4).
2) Pull out the drain cap at the back right of the indoor unit. (Fig. 1) · Hold the convex section at the end and pull the drain cap.
3) Pull out the drain hose at the back left of the indoor unit. (Fig. 2) · Hold the claw marked by the arrows and pull out the drain hose forward.
4) Put the drain cap into the section to which the drain hose is to be attached at the rear of the indoor unit. (Fig. 3) · Insert a screwdriver into the hole on the cap and insert the cap fully into the drain pan.
5) Insert the drain hose fully into the drain pan at the back right of the indoor unit. (Fig. 4) · Check if the hose is hooked securely to the projection of its inserting part at the drain pan.
6) Insert the drain hose into wall hole sleeve (C), and attach the upper part of indoor unit onto the installation plate (1). Then, shift the indoor unit completely to the left to make placing the piping in the back of the unit easier.
7) Cut out a piece of cardboard from the shipping box, roll it up, hook it onto the back rib, and use it as a spacer to lift the indoor unit. (Fig. 5)
8) Connect the refrigerant piping with the extension pipe (B). 9) Attach the lower part of the indoor unit into the installation plate (1).

Felt tape (4) Piping tape (G)
Liquid pipe Gas pipe
Indoor/outdoor unit connecting wire (A)

Piping tape (G) Felt tape (4)

Remove corner box for piping on left side of unit.

Drain cap
Fig. 1
Drain cap Fig. 3

Drain hose Fig. 2
Drain hose Fig. 4

Fig. 5

Rear or bottom piping 1) Place the refrigerant piping and the drain hose together, then rmly apply piping tape
(G) from the end. 2) Insert the piping and the drain hose into the wall hole sleeve (C), and attach the up-
per part of the indoor unit on the installation plate (1). 3) Check if the indoor unit is attached securely on the installation plate (1) by moving
the unit to left and right. 4) Attach the lower part of the indoor unit into the installation plate (1).
Right piping Note: Before performing the following, make sure that wiring is completed, and the conduit cover is installed. (Refer to 2-3.) 1) Place the refrigerant piping and the drain hose together, shift them to left side of the
unit, and then rmly apply piping tape (G) from the end. 2) Insert the piping and the drain hose into the wall hole sleeve (C), and attach the up-
per part of the indoor unit on the installation plate (1). 3) Check if the indoor unit is attached securely on the installation plate (1) by moving
the unit to left and right. 4) Attach the lower part of the indoor unit into the installation plate (1).

Remove corner box for piping on right side of unit

Remove corner box for piping on bottom side of unit
To the left

2-4-2. DRAIN PIPING · If the extension drain hose has to pass through a room, be sure to wrap it with insu-
lation ( eld-supplied). · The drain hose should point downward for easy drain. (Fig. 1) · If the drain hose provided with the indoor unit is too short, connect it with a eld-
supplied drain hose (I). (Fig. 2) · When connecting the drain hose to a hard vinyl chloride pipe, be sure to insert it se-
curely into the pipe. (Fig. 3)
Do not put the drain pipe directly in a drainage ditch where Ammonia or Sulphuric gas may be generated. The evaporated corrosive gas may return to the indoor side through drain pipe and this may cause an unpleasant odor and corrosion on Heat exchanger may occur.

Downward slope
Fig. 1

Drain hose
Soft hose I.D. 19/32 in. (15 mm)
Fig. 2

27-9/16 in. (70 cm) or more
Different diameter joint

Do not make drain piping as shown below.

Do not raise

Accumulated drain water
Air

Drain hose Hard vinyl chloride pipe I.D. 1-3/16 in. (30 mm)
Insert securely
Fig. 3

Tip of drain hose dipped in water

At least 1-31/32 in. (50 mm) gap

Water leakage

Water leakage

Waving

Water leakage

Ditch

3. OUTDOOR UNIT INSTALLATION

3-1. CONNECTING WIRES FOR OUTDOOR UNIT

1) Remove the service panel.

2) Remove the conduit cover.

3) Attach the conduit connectors to the conduit plate with lock nuts then secure it against unit

with screws. 4) Connect the ground wires of indoor/outdoor unit connecting wire (A) and power supply cord (K)

19/32 in. (15 mm)

to the TB support.

5) Loosen the terminal screws, then attach indoor/outdoor unit connecting wire (A) and power

supply cord (K) from the indoor unit correctly to the terminal block. Attach the wires to the

terminal block securely so that the cores cannot be seen, and no external force affects the

Lead

connecting section of the terminal block.

wire

6) Firmly tighten the terminal screws. After tightening, verify that the wires are tightly fastened.

7) Install the conduit cover.

8) Install the service panel securely.

L1 L2
Power supply cord (K)

Service panel Lock nut

Conduit pipe

<MUZ-GS18NA(H)> <MUY-GS18NA>
Terminal block

· Make ground wire a little longer than others. (More than 3-7/8 in. [100 mm]) · For future servicing, leave some slack in the connecting wires. · Be sure to attach each screw to its correspondent terminal when securing the
cord and/or the wire to the terminal block.

<MUZ-GS18NAHZ> Terminal block

Grounding terminal

Conduit cover Conduit plate

TB support
Indoor/outdoor unit connecting wire (A)

to conduit cover

Grounding terminal
Power supply cord (K)

TB support

to conduit cover

Indoor/outdoor unit connecting wire (A)
Power supply cord (K)

3-2. FLARE CONNECTION
1) Cut the copper pipe as straight as possible with a pipe cutter. (Fig. 1, 2) 2) Remove all burrs from the cut section of the pipe, ensuring that precautions are taken to
avoid getting metal shavings into the piping. (Fig. 3) 3) Remove are nuts attached to indoor and outdoor units, then put them on pipe. 4) Flaring work (Fig. 4, 5). Firmly hold copper pipe in the dimension shown in the table. Select A
inch (mm) from the table according to the tool you use. 5) Check
· Compare the ared work with Fig. 6. · If are is defective, cut off the section and repeat procedure.

Pipe diameter inch (mm)

B inch (mm)

A inch (mm)

Clutch type tool for R410A

Clutch type tool for R22

Wing nut type tool for R22

ø 1/4 (6.35) ø 3/8 (9.52) ø 1/2 (12.7) ø 5/8 (15.88)

21/32 (17)
7/8 (22)
1-1/32 (26)
1-5/32 (29)

0 to 0.02 (0 to 0.5)

0.04 to 0.06 (1.0 to 1.5)

0.06 to 0.08 (1.5 to 2.0)
0.08 to 0.10 (2.0 to 2.5)

Tightening torque

ft-lb (kgf·cm)

N·m

10 to 13 (140 to 180)
25 to 30 (350 to 420)
36 to 42 (500 to 575)
54 to 58 (750 to 800)

13.7 to 17.7 34.3 to 41.2 49.0 to 56.4 73.5 to 78.4

3-3. PIPE CONNECTION
· Fasten are nut with a torque wrench as speci ed in the table (refer to 3-2.). · When fastened too tight, are nut may eventually break and cause refrigerant leakage. · Be sure to wrap insulation around the piping. Direct contact with the bare piping may
result in burns or frostbite.
Indoor unit connection Connect both liquid and gas pipings to indoor unit. · Apply a thin coat of refrigeration oil (J) on the ared ends of the pipes. Do not apply re-
frigeration oil on screw threads. Excessive tightening torque will result in damage on the screw. · To connect, rst align the center, then tighten the rst 3 to 4 turns of are nut by hand. · Use tightening torque table above as a guideline for indoor unit side joints, and tighten using two wrenches. Excessive tightening damages the are section.
Outdoor unit connection Connect pipes to stop valve pipe joint of the outdoor unit following the same procedure detailed in Indoor unit connection. · For tightening, use a torque wrench or spanner.
WARNING
When installing the unit, securely connect the refrigerant pipes before starting the compressor.

3-4. INSULATION AND TAPING
1) Cover piping joints with pipe cover. 2) For outdoor unit side, insulate the piping, including valves. 3) Apply piping tape (G) starting from the connection on the outdoor unit.
· When piping has to be installed through a ceiling, closet or where the temperature and humidity are high, use additional eld-supplied insulation to prevent condensation.

Copper pipe

Good 90°

No good

Fig. 1

Tilted Uneven Burred Fig. 2

Burr

Copper pipe

Spare reamer

Pipe cutter

Fig. 3

Flaring tool

Die

Copper pipe

Clutch type Wing nut type Fig. 4
Smooth all around

Flare nut Fig. 5
Inside is shining without any scratches.

Even length all around
Indoor unit connection

Fig. 6

Flare nut
Internal thread side Tighten the are nut with a torque wrench.
Outdoor unit connection

Union joint
External thread side
Grip the nut on the union joint with a spanner.

4. PURGING PROCEDURES, LEAK TEST, AND TEST RUN

4-1. PURGING PROCEDURES AND LEAK TEST
1) Remove service port caps from stop valves on both sides of refrigerant lines. (The stop valves are fully closed when shipped.) Leave closed.
2) Connect gauge manifold to ports of stop valves.

Valve stem (inside)
Close Open

Stop valve cap (Torque 15 to 22 ft-lb, 19.6 to 29.4 N·m, 200 to 300 kgf cm)

Hexagonal wrench

­14.7 psi [Gauge] (­0.101 Mpa)
Stop valve for LIQUID
Handle Low
Stop valve for GAS

Compound pressure gauge (for R410A)
Pressure gauge (for R410A)
Gauge manifold valve (for R410A)
Handle High
Charge hose (for R410A)

Service port cap (Torque 10 to 13 ft -Ib, 13.7 to 17.7 N·m, 140 to 180 kgf·cm)

Adapter for preventing the back ow

Vacuum pump (or the vacuum pump with the function to prevent the back ow)

Precautions when using the control valve When attaching the control valve to the service port, valve core may deform or loosen if excess pressure is applied. This may cause gas leak.

A Control valve
Open Close Body

Service port Charge hose

When attaching the control valve to the service port, make sure that the valve core is in closed position, and then tighten part A. Do not tighten part A or turn the body when valve core is in open position.

3) Evacuate the system to 4000 microns from both service valves. System manifold gauges must not be used to measure vacuum. A micron gauge must be used at all times. Break the vacuum with Nitrogen(N2) into the discharge service valve to 0 PSIG.
4) Evacuate the system to 1500 microns. Break the vacuum with Nitrogen(N2) into the discharge service valve to 0 PSIG.
5) Evacuate the system to 500 microns. 6) Close gauge manifold valves, stop the pump, and conduct a 30 minute rise test. 7) System should hold 500 microns for a minimum of 1 hour. 8) Fully open the valve stem of all stop valves on both sides of gas pipe and liquid pipe
by the hexagonal wrench. If the valve stem hits the stopper, do not turn it any further. Operating without fully opening lowers the performance and this causes trouble. 9) Refer to 1-3 and charge the prescribed amount of additional refrigerant if needed. Be sure to charge slowly with liquid refrigerant. Otherwise composition of the refrigerant in the system may be changed and affect performance of the air conditioner. 10) Remove gauge manifolds and replace service port caps and tighten. 11) Leak test

4-2. TEST RUN
1) Insert power supply plug into the power outlet and/or turn on the breaker.
2) Press the E.O. SW once for COOL, and twice for HEAT (only MSZ series) operation. Test run will be performed for 30 minutes. If the power lamp blinks every 0.5 seconds, inspect the indoor/outdoor unit connecting wire (A). After the test run, emergency COOL mode (75ºF [24ºC] COOL) will start.
3) To stop operation, press the E.O. SW several times until all LED lamps turn off. Refer to operating instructions for details.

Emergency operation switch (E.O. SW)

Checking the remote (infrared) signal reception Press the ON/OFF button on the remote controller (3) and listen for an audible indicator from the indoor unit. Press the ON/OFF button again to turn the air conditioner off. · Once the compressor stops, the restart preventive device operates so the compressor
will not operate for 3 minutes to protect the air conditioner.
4-3. AUTO RESTART FUNCTION
This product is equipped with an auto restart function. When the power supply is cut off during operation, such as during blackouts, the function automatically starts operation in the previous setting once the power supply is resumed. (Refer to the operating instructions for details.)
Caution: · After test run or remote signal reception check, turn off the unit with the E.O. SW or
the remote controller before turning off the power supply. If this procedure is not performed, the unit will automatically begin operation when power supply is resumed. To the user · After installing the unit, explain to the user about auto restart function. · If auto restart function is unnecessary, it can be deactivated. Consult the service representative to deactivate the function. Refer to the service manual for details.
4-4. EXPLANATION TO THE USER
· Using the OPERATING INSTRUCTIONS, explain to the user how to use the air conditioner (the remote controller, removing the air lters, placing or removing the remote controller from the remote controller holder, cleaning methods, precautions for operation, etc.)
· Recommend that the user read the OPERATING INSTRUCTIONS carefully.

5. RELOCATION AND MAINTENANCE
5-1. REMOVING AND INSTALLING THE PANEL ASSEMBLY
Removal procedure (Fig. 1) 1) Open the front panel. 2) Remove the 3 screws which x the panel assembly. 3) Close the front panel. 4) Remove the panel assembly. Be sure to remove its bottom end rst.

1

3

42

22 4

Fig. 1

Installation procedure (Fig. 2)
1) Install the panel assembly following the removal procedure in reverse. 2) Be sure to press the positions as indicated by the arrows in order to attach the
assembly completely to the unit.

* Do not hold the A part when installing/removing or carrying the panel, or the panel might be damaged.

Fig. 2

A part : lower part of air outlet of the panel

5-2. REMOVING THE INDOOR UNIT
Remove the bottom of the indoor unit from the installation plate. When releasing the corner part, release both left and right bottom corner part of indoor unit and pull it downward and forward as shown in the gure on the right.

5-3. PUMPING DOWN
When relocating or disposing of the air conditioner, pump down the system following the procedure below so that refrigerant is not released into the atmosphere. 1) Connect the gauge manifold valve to the service port of the stop valve on the gas pipe side of the outdoor unit. 2) Fully close the stop valve on the liquid pipe side of the outdoor unit. 3) Close the stop valve on the gas pipe side of the outdoor unit almost completely so that it can be easily closed fully when the pressure gauge shows 0 psi [Gauge] (0 Mpa). 4) Start the emergency COOL operation.
To start the emergency operation in COOL mode, disconnect the power supply plug and/or turn off the breaker. After 15 seconds, connect the power supply plug and/or turn on the breaker, and then press the E.O. SW once. (The emergency COOL operation can be performed continuously for up to 30 minutes.) 5) Fully close the stop valve on the gas pipe side of the outdoor unit when the pressure gauge shows (0.1 to 0 psi [Gauge] (0.05 to 0 Mpa)). 6) Stop the emergency COOL operation. To stop operation, press the E.O. SW several times until all LED lamps turn off. Refer to operating instructions for details.
WARNING
When the refrigeration circuit has a leak, do not execute pump down with the compressor. When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes. The compressor may burst if air etc. get into it.

6. CONNECTING THE INTERFACE/CONNECTOR CABLE TO THE AIR CONDITIONER
· Connect the INTERFACE/CONNECTOR CABLE to the Indoor electronic control P.C. board of the air conditioner with the connecting cable. · Cutting or extending the connecting cable of the INTERFACE/CONNECTOR CABLE results in defects in connecting.
Do not bundle the connecting cable together with power supply cord, indoor/outdoor connecting wire, and/or earth wire. Keep as much distance as possible between the connecting cable and those wires. · The thin part of the connecting cable should be stored and placed where customers cannot touch it.

Connecting

Air conditioner

Thin part of the connecting cable. Place this part where customers cannot touch it.

Interface unit Connector

Indoor control P.C.

board

CN105

Thick part of the connecting cable

Indoor control P.C. board holder

(1) Remove the panel and the lower right corner box. (2) Open the indoor control P.C. board holder 90 degrees and remove it. (3) Join the connecting cable to CN105 on the indoor control P.C. board.
(4) Attach the cable clamp provided with the interface to the thick part of the connecting cable with a screw 4×16 as shown in the gure.
(5) Hook the connecting cable into the ribs as shown in the gure. (6) Install the indoor control P.C. board holder and then stow the extra connecting cable where
indicated in the gure. Install the lower right corner box and the panel to the original position.

WARNING
Fix the connecting cable at the prescribed position securely. Incorrect installaWLRQPDFDXVHHOHFWULFVKRFN¿UHDQGRUPDOIXQFWLRQ

HEAD OFFICE: TOKYO BUILDING, 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN