En-7
Drain
pipe
Outlet
air
fl
ow
Arrange the drain pipe
lower than this portion
GOOD
• When the pipe is long, install supporters.
Supporter
60 to 79 in (1.5 to 2 m)
Trap
Rise
PROHIBITED
Air bleeding
3. 5. 2. Check for drainage
Pour about 1 liter of water from the position shown in the diagram or from the air
fl
ow outlet
to the dew tray. Check for any abnormalities such as strange noises and whether the drain
pump functions normally.
CAUTION
Make sure the drain water is properly drained.
3. 6. Pipe installation
WARNING
• During installation, make sure that the refrigerant pipe is attached
fi
rmly before you
run the compressor.
Do not operate the compressor under the condition of refrigerant piping not attached
properly with 2-way or 3-way valve open. This may cause abnormal pressure in the
refrigeration cycle that leads to breakage and even injury.
• During the pump-down operation, make sure that the compressor is turned off before
you remove the refrigerant piping.
Do not remove the connection pipe while the compressor is in operation with 2-way
or 3-way valve open. This may cause abnormal pressure in the refrigeration cycle
that leads to breakage and even injury.
• When installing and relocating the air conditioner, do not mix gases other than the
speci
fi
ed refrigerant (R410A) to enter the refrigerant cycle.
If air or other gas enters the refrigerant cycle, the pressure inside the cycle will rise to
an abnormally high value and cause breakage, injury, etc.
• If refrigerant leaks while work is being carried out, ventilate the area. If the refrigerant
comes in contact with a
fl
ame, it produces a toxic gas.
CAUTION
• Be more careful so that foreign matter (oil, water, etc.) does not enter the piping than
with refrigerant R410A models. Also, when storing the piping, securely seal the open-
ings by pinching, taping, etc.
• While brazing the pipes, be sure to blow dry nitrogen gas through them.
3. 6. 1. Pipe connection
■
Flaring
Use special pipe cutter and
fl
are tool designed for R410A pipework.
(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 unit(s) and outdoor
unit or branch box respectively) onto the pipe and perform the
fl
are processing with a
fl
are tool. Use the special R410A
fl
are tool, or the conventional
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.
Check if [L] is
fl
ared uniformly
and is not cracked or scratched.
Pipe
Die
B
A
L
Pipe outside diameter
[in (mm)]
Dimension A [in (mm)]
Dimension B
0 (0)
-0.015 (-0.4)
[in (mm)]
Flare tool for R410A,
clutch type
1/4 (6.35)
0 to 0.020
(0 to 0.5)
3/8 (9.1)
3/8 (9.52)
1/2 (13.2)
1/2 (12.70)
5/8 (16.6)
5/8 (15.88)
3/4 (19.7)
3/4 (19.05)
15/16 (24.0)
When using conventional (R22) flare tools to flare R410A pipes, the dimension A should
be approximately 0.020 in (0.5 mm) more than indicated in the table (for flaring with
R410A flare tools) to achieve the specified flaring. Use a thickness gauge to measure the
dimension A. It is recommended that a R410A flaring tool is used.
Width across
fl
ats
Pipe outside diameter
[in (mm)]
Width across flats of Flare
nut [in (mm)]
1/4 (6.35)
11/16 (17)
3/8 (9.52)
7/8 (22)
1/2 (12.70)
1 (26)
5/8 (15.88)
1-1/8 (29)
3/4 (19.05)
1-7/16 (36)
■
Bending pipes
• If pipes are shaped by hand, 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 dif
fi
cult
to bend or stretch them any more.
• Do not bend or stretch the pipes more than 3 times.
CAUTION
• To prevent breaking of the pipe, avoid sharp bends. Bend the pipe with a radius of
curvature of 1- 15/16 in (50 mm) or over.
• If the pipe is bent repeatedly at the same place, it will break.
■
Flare connection
CAUTION
• Be sure to apply the pipe against the port on the indoor unit correctly. If the centering
is improper, the
fl
are nut cannot be tightened smoothly. If the
fl
are nut is forced to
turn, the threads will be damaged.
• Do not remove the
fl
are nut from the indoor unit pipe until immediately before con-
necting the connection pipe.
• Do not use mineral oil on
fl
ared part. Prevent mineral oil from getting into the system
as this would reduce the lifetime of the units.
(1) Detach the caps and plugs from the pipes.
(2) Centering the pipe against port on the indoor unit, turn the
fl
are nut with your hand.
(3) When the
fl
are nut is tightened properly by your hand, hold the body side coupling with
a separate spanner, then tighten with a torque wrench. (See the table below for the
fl
are nut tightening torques.)
9381386246_IM.indb 7
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