6
English
•
Refer to Table 1 for tightening torque.
Table 1
CAUTION
Overtightening may damage the flare and cause leaks.
Be careful for oil not to adhere to any portions other
than a flare part. If oil adhere to resin parts etc., there is
a possibility of damaging by deterioration.
•
Refer to Table 2 if no torque wrench is available.
Using a wrench to tighten flare nuts causes the tightening
torque to suddenly grow much tighter after a certain point.
From there, tighten the nut further by the appropriate angle
listed in Table 2.
(2) After the work is finished, make sure to check that
there is no gas leak.
(3) After checking for gas leaks, be sure to insulate the
pipe connections referring to Fig. 8.
•
Insulate using the insulation for fitting (3) (4) included with
the liquid and gas pipes. Besides, make sure the insula-
tion for fitting (3) (4) on the liquid and gas piping has its
seams facing up.
(Tighten both edges with clamp (9).)
•
For the gas piping, wrap the mid. sealing pad (6) over the
insulation for fitting (4) (flare nut part).
CAUTION
Be sure to insulate any field piping all the way to the piping
connection inside the unit. Any exposed piping may cause
condensation or burns if touched.
•
When brazing the refrigerant piping, perform nitrogen
replacement first, or perform the brazing (CAUTION 2) while
feeding nitrogen into the refrigerant piping (CAUTION 1), and
finally connect the indoor unit using the flare connections.
(Refer to Fig. 9)
CAUTION
1. When brazing a pipe while feeding nitrogen inside the
pipe, make sure to set the nitrogen pressure to 0.02 MPa
(0.2 kg/cm
2
) using the pressure reducing valve. (This
pressure is such that breeze is blown to your cheek.)
2. Do not use a flux when brazing the refrigerant pipe joints.
Use phosphor copper brazer (BCuP-2: JIS Z 3264/B-
Cu93P-710/795: ISO 3677) which does not require flux.
(Using a flux containing chlorine may cause the piping to
corrode. Using a welding flux containing fluorine may
cause the refrigerant lubricant to deteriorate, and affect
adversely the refrigerant piping system.)
Not recommendable but in case of emergency
You must use a torque wrench but if you are obliged to install the
unit without a torque wrench, you may follow the installation
method mentioned below.
After the work is finished, make sure to check that there is
no gas leak.
When you keep on tightening the flare nut with a spanner, there
is a point where the tightening torque suddenly increases. From
that position, further tighten the flare nut the angle shown below:
Table 2
Pipe
size
Tightening torque
Flare dimen-
sion A (mm)
Flare shape
Ø6.4
15 – 17 N·m
8.7 – 9.1
Ø9.5
33 – 39 N·m
12.8 – 13.2
Ø12.7
50 – 60 N·m
16.2 – 16.6
Ø15.9
63 – 75 N·m
19.3 – 19.7
A
45
0
Ⳳ
2
0
R0.4-0.8
90
0
Ⳳ
2
0
Main unit
Wrap over the top of the
flare nut connection.
(accessory)
(accessory)
Insulation for fitting (3)
(accessory)
Liquid pipe
Fig. 8
Main unit
Attach to base
Piping insulation material
(main unit)
Piping insulation material
(Field supply)
Turn seams up
Flare nut connection
Clamp (9) (accessory)
Piping insulation material
(Field supply)
Clamp (9)
(accessory)
Liquid Piping Insulation Procedure
Gas Piping Insulation Procedure
Insulation for fitting (4)
Mid. sealing pad (6)
Turn seams up
Flare nut connection
Attach to base
Piping insulation
material (main unit)
Gas pipe
Pipe size
Further tightening angle
Recommended arm
length of tool
Ø6.4 (1/4”)
60 to 90 degrees
Approx. 150mm
Ø9.5 (3/8”)
60 to 90 degrees
Approx. 200mm
Ø2.7 (1/2”)
30 to 60 degrees
Approx. 250mm
Ø15.9 (5/8”)
30 to 60 degrees
Approx. 300mm
Fig. 9
Nitrogen
Nitrogen
Hands
valve
Pressure-reducing valve
Taping
Part to be brazed
Refrigerant piping
4PEN325876-1F.book Page 6 Thursday, April 20, 2017 8:20 AM
