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Digital Inverter
Installation Manual
7
EN-13
EN-14
Refrigerant Piping Connection
CAUTION
TAKE NOTE OF THESE 4 IMPORTANT POINTS
BELOW FOR PIPING WORK
1.
Keep dust and moisture away from inside the
connecting pipes.
2.
Tightly connect the connection between pipes and
the unit.
3.
Evacuate the air in the connecting pipes using a
VACUUM PUMP.
4.
Check for gas leaks at connection points.
Piping connection
REQUIREMENT
On the gas side, be sure to use the Ø19.1 mm pipe
provided with the outdoor unit.
Flaring
1.
Cut the pipe with a pipe cutter.
Be sure to remove burrs that may cause a gas leak.
2.
Insert a flare nut into the pipe, and then flare the pipe.
Use the flare nuts supplied with the air conditioner
or those for R410A.
Insert a flare nut into the pipe, and flare the pipe.
As the flaring sizes of R410A differ from those of
refrigerant R22, the flare tools newly manufactured
for R410A are recommended.
However, the conventional tools can be used by
adjusting the projection margin of the copper pipe.
Projection margin in flaring: B (Unit: mm)
Rigid (Clutch type)
Flaring diameter size: A (Unit: mm)
* In case of flaring for R410A with the conventional flare
tool, pull the tool out approx. 0.5 mm more than that
for R22 to adjust it to the specified flare size.
The copper pipe gauge is useful for adjusting the
projection margin size.
Connecting the Gas Side Pipe
REQUIREMENT
• Be sure to use the Ø19.1 mm pipe and joint provided
as accessories of the outdoor unit to connect the gas
side Ø19.1 mm pipe and Ø28.6 mm pipe.
• When leading out the pipes toward the front, to one of
the sides or toward the rear, use the Ø19.1 mm pipe
and elbow provided as accessories of the outdoor unit,
and adjust the bending direction. Cut the Ø19.1 mm
pipe to the required length before using it.
Liquid side
Outer diameter
Thickness
Ø12.7 mm
0.8 mm
Gas side
Outer diameter
Thickness
Ø19.1 mm
1.2 mm
Ø28.6 mm
1.0 mm (half hard)
Outer diam. of
copper pipe
R410A tool
used
Conventional
tool used
R410A
1.0 to 1.5
12.7
0 to 0.5
19.1
Outer diam. of copper
pipe
A
12.7
16.6
19.1
24.0
B
A
+0
–0.4
1.
Align the provided Ø19.1 mm pipe with the pipe
lead-out direction, and shape it so that its end
comes out from the outdoor unit.
2.
On the outside of the outdoor unit, use the provided
joints, and braze the Ø19.1 mm pipe and Ø28.6 mm
pipe.
REQUIREMENT
• Before proceeding to weld the refrigerant pipe, be sure
to pass nitrogen through the pipe to prevent oxidation
inside it. If nitrogen is not passed through the pipe, the
refrigerating cycle may become clogged by oxidized
scales.
• The Ø28.6 mm pipe cannot be passed through the
pipe cover and knockout hole in the base plate so be
sure to connect the Ø19.1 mm pipe and Ø28.6 mm
pipe outside the outdoor unit.
Tightening of Connecting Part
1.
Align the centers of the connecting pipes and fully
tighten the flare nut with your fingers. Then fix the
nut with a wrench as shown in the figure and tighten
it with a torque wrench.
2.
As shown in the figure, be sure to use two wrenches
to loosen or tighten the flare nut of the valve on the
gas side. If you use a single crescent, the flare nut
cannot be tightened to the required tightening
torque.
On the other hand, use a single crescent to loosen
or tighten the flare nut of the valve on the liquid side.
(Unit: N•m)
Ø19.1 mm pipe
(accessory)
Ø19.1 mm pipe
(accessory)
Brazing
Elbow
(accessory)
Ø19.1 mm pipe
(accessory)
Ø19.1 mm pipe
(accessory)
Ø28.6 mm pipe
(procured locally)
Joint
(accessory)
Joint (accessory)
: Brazing
Outer dia. of copper pipe
Tightening torque
12.7 mm (diam.)
50 to 62
(5.0 to 6.2 kgf•m)
19.1 mm (diam.)
100 to 120
(10.0 to 12 kgf•m)
Half union or packed valve
Flare nut
Externally
threaded side
Internally
threaded side
Fix with wrench.
Tighten with torque wrench.
Cover
Piping valve
Tightened
Flare nut
Cap
Loosened
Valve at gas side
