4
Piping Works And Flaring Technique
Do not use contaminated or damaged copper tubing. If any
piping, evaporator or condenser had been exposed or had been
opened for 15 seconds or more, vacuum the system. Generally,
do not remove plastic, rubber plugs and brass nuts from the
valves, fittings, tubings and coils until it is ready for connection.
If any brazing work is required, ensure that the nitrogen gas is
passed through piping and joints while the brazing work is
being done. This will eliminate soot formation on the inside
walls of the copper tubings.
Cut the pipe stage by stage, advancing the blade of pipe cutter
slowly. Extra force and deep cut will cause more
distortion of pipe and therefore extra burr.
Remove burrs from cut edges of pipes with a remover as shown
in Fig. R. This will avoid unevenness on the flare faces which
will cause gas leak. Hold the pipe on top position and burr
remover at lower position to prevent metal chips from entering
the pipe.
Insert the flare nuts mounted on the connection parts of both
indoor and outdoor unit, into the copper pipes.
The exact length of pipe protruding from the face of the flare
die is determined by the flaring tool.
Fix the pipe firmly on the flare die. Match the centers of both
the flare die and the flaring punch, and tighten flaring punch
fully.
1/4t
Cutting Copper Tube
Copper Tube
Swaging Block
Ø Tube, D
A (mm)
Inch
mm
Imperial
Rigid
1/4"
6.35
1.3
0.7
3/8"
9.52
1.6
1.0
1/2"
12.70
1.9
1.3
5/8"
15.88
2.2
1.7
3/4"
19.05
2.5
2.0
Piping Connection To The Units
Align the center of the piping and sufficiently tighten the flare
nut with fingers.
Finally, tighten the flare nut with torque wrench
until the wrench clicks.
When tightening the flare nut with the torque wrench,
ensure that the direction for tightening follows the arrow on
the wrench.
The refrigerant pipe connection are insulated by polyurethane
(ARMAFLEX type or similar).
Pipe Size, mm (in)
Torque (Nm)
6.35 (1/4)
18
9.53 (3/8)
42
12.7 (1/2)
55
15.88 (5/8)
65
19.05 (3/4)
78
Spanar
Torque Wrench
Indoor Piping
Flare Nut
Flared Tube
Flare Joint
Fig. R
Remove Burr
Copper Tube