Indoor Unit Installation - Mitsubishi Electric MSZ-GS18NA Installation Manual

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 fix-
ing screws (2) firmly.
• 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 inch x 13/16 inch · 7/16 inch x 1 inch (11 mm × 20 mm
· 11 mm × 26 mm) oval hole (17-3/4 inches [450 mm] pitch).
• If the recessed bolt is too long, change it for a shorter one (field-supplied).
2-2. Drilling
1) Determine where the holes will be located on the wall.
2) Drill a ø 3 inches (75 mm) hole. The outdoor side should be 6/32 to 9/32 inch (5 to 7
mm) lower than the indoor side.
3) Insert wall hole sleeve (C).
2-3. Connecting Wires for the Indoor Unit
Note:
When the indoor unit is powered from the outdoor unit, depending on local code, a discon-
nect switch needs to be installed to a power supply circuit.
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 appear-
ing inside should be less than 3/8 inch (10 mm). (Fig. 1) Elbow joint should appear less
than 1-3/16 inches (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 fas-
tened.
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 termi-
nal in order to connect a
ground wire to terminal.
Grounding terminal**
OUTDOOR UNIT
<MUZ-GS18NA(H)>
<MUY-GS18NA>
Power supply
208/230 V AC,
1 phase 2 wires,
60 Hz
INDOOR UNIT
Terminal block
208/230 V AC,
1 phase, 60 Hz
OUTDOOR UNIT
<MUZ-GS18NAHZ>
Ground
Grounding terminal**
Lead
wire
• Make ground wire a little longer than
others. (More than 1-9/16 inches [40
mm])
Installation plate (1)
5 1/4 inches
(133 mm)
or more
Wall
Fixing
screw (2)
Fixing screw
Conduit cover
Indoor control
P.C. board holder
Grounding
• Connect wires to the appropriate terminals
terminal**
• For future servicing, leave some slack in the connecting wires.
Disconnect
switch*
Conduit plate
19/32 inch
(15 mm)
Remove corner box L for
piping on bottom side of unit.
Remove corner box L for
piping on left side of unit.
Fig. 3
Ceiling
4 3/8 inches (111 mm) or more
5 3/16 inches (132 mm) or more for
left and left back piping (using spacer)
Level
Insert
the
scale. *
Wall
Ø 3 inches
6/32-9/32 inch
(75 mm)
(5-7 mm)
Outdoor side
Electrical box
Electrical cover
Elbow joint
Lock nut
(for right, left, or downward piping)
Fixing screw
Conduit plate
Less than 3/8
inch (10 mm)
Lock nut
Conduit plate
Conduit pipe or
elbow joint
(for right, left, or downward piping)
Fig. 1
Corner box L
Corner box R
Remove corner box R for
piping on bottom side of unit.
Fig. 4
6 5/8 inches
(168 mm)
or more
4 inches (100 mm)
Wall
Center of
Align the
ø3 inches
scale with
(ø75 mm) hole
the line. *
* Same for left hole.
Grounding
terminal
Indoor terminal
block
Conduit pipe
(for rear piping)
or
Less than 1-3/16
inches (30 mm)
Elbow joint
Fig. 2
Remove corner box R for
piping on right side of unit.
Fig. 5