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Ceiling panel
(2) Fasten the indoor unit into place by tightening-up the special "B" bolts and the M10
nuts. Make sure that unit is secure and will not shift back and forth.
[For Half-Concealed Installation]
When installing the indoor unit in a semi-concealed orientation, make sure to reinforce the
insulation (fi eld supply) of the unit on all sides. Drops of water may fall from the unit if it is
not thoroughly insulated.
In order to check the drainage, be sure to use a level during installation of the indoor
unit. If the installation site of the indoor unit is not level, water leakage may occur.
4. PIPE INSTALLATION
]
Be more careful that foreign matter (oil, water, etc.) does not enter the piping than with
refrigerant R410A models. Also, when storing the piping, securely seal the openings
by pinching, taping, etc.
While welding the pipes, be sure to blow dry nitrogen gas through them.
] 1
4.1. Selecting the pipe material
Do not use existing pipes from another refrigeration system or refrigerant.
Use pipes that have clean external and internal sides without any contamination which
may cause trouble during use, such as sulfur, oxide, dust, cutting waste, oil, or water.
It is necessary to use seamless copper pipes.
Material : Phosphor deoxidized seamless copper pipes
It is desirable that the amount of residual oil is less than 0.04 oz /100 ft. (40 mg /10 m).
Do not use copper pipes that have a collapsed, deformed, or discolored portion
(especially on the interior surface). Otherwise, the expansion valve or capillary tube
may become blocked with contaminants.
Improper pipe selection will degrade performance. As an air conditioner using R410A
incurs pressure higher than when using conventional (R22) refrigerant, it is necessary
to choose adequate materials.
• Thicknesses of copper pipes used with R410A are as shown in the table.
• Never use copper pipes thinner than those indicated in the table even if they are
available on the market.
Thicknesses of Annealed Copper Pipes (R410A)
Pipe outside diameter [in. (mm)]
1/4 (6.35)
3/8 (9.52)
1/2 (12.70)
5/8 (15.88)
3/4 (19.05)
En-5
Wall
INDOOR UNIT
Glass wool insulate (Field supply)
(13/32 to 25/32 in. (10 to 20 mm) thick)
INDOOR UNIT
(Top view)
Wall
Ceiling panel
CAUTION
CAUTION
CAUTION
Thickness [in. (mm)]
0.032 (0.80)
0.032 (0.80)
0.032 (0.80)
0.039 (1.00)
0.047 (1.20)
1
4.2. Pipe requirement
Refer to the Installation Manual of the outdoor unit for description of the length of
connecting pipe or for difference of its elevation.
•
Use pipe with water-resistant heat insulation.
Install heat insulation around both the gas and liquid pipes. Failure to do so may
cause water leaks.
Use heat insulation with heat resistance above 248°F (120°C). (Reverse cycle model only)
In addition, if the humidity level at the installation location of the refrigerant piping is
expected to exceed 70 %, install heat insulation around the refrigerant piping.
If the expected humidity level is 70 to 80 %, use heat insulation that is 19/32 in.
(15 mm) or thicker and if the expected humidity exceeds 80 %, use heat insulation
that is 25/32 in. (20 mm) or thicker. If heat insulation is used that is not as thick as
specifi ed, condensation may form on the surface of the insulation.
In addition, use heat insulation with heat conductivity of 0.045 W/(m·K) or less
(at 68°F (20°C)).
1
4.3. Flare connection (pipe connection)
4.3.1. Flaring
Use special fl are tool exclusive for R410A.
(1) Cut the connection pipe to the necessary length with a pipe cutter.
(2) Hold the pipe downward so that cuttings will not enter the pipe and remove any burrs.
(3) Insert the fl are nut (always use the fl are nut attached to the indoor and outdoor units
respectively) onto the pipe and perform the fl are processing with a fl are tool. Use
the special R410A fl are tool. Leakage of refrigerant may result if other fl are nuts are
used.
(4) Protect the pipes by pinching them or with tape to prevent dust, dirt, or water from
entering the pipes.
B
Die
A
Pipe
Dimension A [in. (mm)]
Pipe outside diameter
Flare tool for R410A,
[in. (mm)]
1/4 (6.35)
3/8 (9.52)
1/2 (12.70)
5/8 (15.88)
3/4 (19.05)
When using conventional (R22) fl are tools to fl are R410A pipes, the dimension A should
be approximately 0.020 in. (0.5 mm) more than indicated in the table (for flaring with
R410A fl are tools) to achieve the specifi ed fl aring. Use a thickness gauge to measure the
dimension A. It is recommended that a R410A fl aring tool is used.
Pipe outside diameter
Width across
[in. (mm)]
fl ats
1/4 (6.35)
3/8 (9.52)
1/2 (12.70)
5/8 (15.88)
3/4 (19.05)
4.3.2. Bending pipes
•
The pipes are shaped by your hands or pipe bender. Be careful not to collapse them.
•
Do not bend the pipes in an angle more than 90°.
•
When pipes are repeatedly bend or stretched, the material will harden, making it diffi cult
to bend or stretch them any more. Do not bend or stretch the pipes more than 3 times.
To prevent breaking of the pipe, avoid sharp bends.
If the pipe is bent repeatedly at the same place, it will break.
CAUTION
CAUTION
Check if [L] is fl ared uniformly
and is not cracked or scratched.
L
Dimension B
[in. (mm)]
clutch type
11/32 (9.1)
17/32 (13.2)
0 to 0.020
21/32 (16.6)
(0 to 0.5)
25/32 (19.7)
15/16 (24.0)
Width across flats of Flare nut
[in. (mm)]
21/32 (17)
7/8 (22)
1-1/32 (26)
1-5/32 (29)
1-13/32 (36)
CAUTION
0 (0)
-0.015 (-0.4)
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