Haier MRV 5-RC VP1-112B Service Manual page 120

<Table-3>
Tube size Tightening torque (N.m) Machined flare size A (mm)
Ø6.35 14.2~17.2
Ø9.52 32.7~39.9
Ø12.7 49.5~60.3
Ø15.88 61.8~75.4
Ø19.05 97.2~118.8
Ø22.22 117.2~138.8
<Table-4>
Pipe size Tightening angle
Ø6.35
Ø9.52
Ø12.7
Ø15.88
Ø19.05
Ø22.22
<Note>
• Excessive tightening will result in cracking at the flare and refrigerant leakage.
• To weld the refrigerant pipe, please make nitrogen replacement (*1), or send nitrogen (*2) into the refrigerant pipe
while welding the pipe (refer to Fig.9). Finally use the flare or flange to connect the indoor unit and valve box.
(*1) Nitrogen replacement method is provided in the multi-split system work manual.
(*2) If nitrogen flowing and welding proceed simultaneously, do use pressure reducing valve. Approximately 0.02
MPa (0.2 Kg/cm with a slight feeling of breeze) pressure is quite proper.
8.7~9.1
12.8~13.2
16.2~16.6
19.3~19.7
23.7—23.9
28.2-28.5
Recommended tool length (mm)
60°~90°
60°~90°
30°~60°
30°~60°
20°~35°
15°~30°
Apply refrigerant oil
Weld
Nitrogen
Refrigerant pipe
Flare shape
150
200
250
300
450
600
Fig.9
Nitrogen cylinder
Binding
Fig.10
117