En-5
1
4.2. Pipe requirement
CAUTION
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.
CAUTION
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 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 15 mm or
thicker and if the expected humidity exceeds 80 %, use heat insulation that is 20 mm
or thicker. If heat insulation is used that is not as thick as speci
fi
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 20 °C).
1
4.3. Flare connection (pipe connection)
WARNING
Tighten the
fl
are nuts with a torque wrench using the speci
fi
ed tightening method.
Otherwise, the
fl
are nuts could break after a prolonged period, causing refrigerant to
leak and generate a hazardous gas if the refrigerant comes into contact with a
fl
ame.
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 (or
RB unit) 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.
L
Check if [L] is
fl
ared uniformly and
is not cracked or scratched.
Die
Pipe
A
B
Pipe outside diameter [mm
(in.)]
Dimension A [mm]
Dimension B
-
0
0.4
[mm]
Flare tool for R410A, clutch
type
6.35 (1/4)
0 to 0.5
9.1
9.52 (3/8)
13.2
12.70 (1/2)
16.6
15.88 (5/8)
19.7
19.05 (3/4)
24.0
When using conventional (R22)
fl
are tools to
fl
are R410A pipes, the dimension A should
be approximately 0.5 mm more than indicated in the table (for
fl
aring with R410A
fl
are
tools) to achieve the speci
fi
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
[mm (in.)]
Width across flats of Flare nut
[mm]
6.35 (1/4)
17
9.52 (3/8)
22
12.70 (1/2)
26
15.88 (5/8)
29
19.05 (3/4)
36
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 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.
If the pipe is bent repeatedly at the same place, it will break.
Width across
fl
ats
4.3.3. Pipe connection
Connect the silencer pipe to the small (liquid) pipe.
Centering the pipe against port on the indoor unit, turn the
fl
are nut with your hand.
Be sure that the small pipe is completely installed before connecting the large pipe.
Indoor unit side
Silencer pipe
(Accessories)
CAUTION
Be sure to install the pipe against the port on the indoor unit and the outdoor unit
correctly. If the centering is improper, the
fl
are nut cannot tightened smoothly. If the
fl
are nut is forced to turn, the threads will be damaged.
Do not remove the flare nut from the indoor unit pipe until immediately before
connecting 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.
If necessary, cut the silencer pipe and use it.
Silencer pipe
(Accessories)
CAUTION
Hold the torque wrench at its grip, keeping it at a right angle with the pipe, in order to
tighten the
fl
are nut correctly.
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.
Connection pipe
Torque wrench
Indoor unit pipe
(Body side)
Tighten with 2 wrenches.
Holding wrench
Flare nut
Flare nut [mm (in.)]
Tightening torque [N·m (kgf·cm)]
6.35 (1/4) dia.
16 to 18 (160 to 180)
9.52 (3/8) dia.
32 to 42 (320 to 420)
12.70 (1/2) dia.
49 to 61 (490 to 610)
15.88 (5/8) dia.
63 to 75 (630 to 750)
19.05 (3/4) dia.
90 to 110 (900 to 1,100)
9367701100-01_IM.indb Sec1:5
9367701100-01_IM.indb Sec1:5
2012-7-12 14:01:32
2012-7-12 14:01:32
