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.
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.
Ø Tube, D
Inch
mm
1/4"
6.35
3/8"
9.52
1/2"
12.70
5/8"
15.88
3/4"
19.05
Pipe Size, mm (in)
6.35 (1/4)
9.53 (3/8)
12.7 (1/2)
15.88 (5/8)
19.05 (3/4)
Cutting Copper Tube
1/4t
Copper Tube
Fig. R
Remove Burr
Copper Tube
Swaging Block
A (mm)
Imperial
Rigid
1.3
0.7
1.6
1.0
1.9
1.3
2.2
1.7
2.5
2.0
Torque, Nm (ft-lb)
18 (13.3)
42 (31.0)
55 (40.6)
65 (48.0)
78 (57.6)
1-9
Flared Tube
Flare Joint
Indoor Piping
Torque Wrench
Spanar
Flare Nut