InstallationManual.book Page 13 Tuesday, January 9, 2007 3:22 PM
Refrigerant Piping Connection
Flaring
1.
Cut the pipe with a pipe cutter.
2.
Insert a flare nut into the pipe, and flare the pipe.
• Projection margin in flaring: A (Unit: mm)
Rigid (Clutch type)
Outer diameter of copper pipe
6.35
9.52
12.7
Die
Pipe
3.
Flaring size : B (Unit : mm)
• In case of flaring for R410A with the conventional flare tool, pull it out approx. 0.5 mm more than that of R22 to adjust the
specified flare size. The copper pipe gauge is useful for adjusting projection margin size.
Tighten the connection
Align the centers of the connecting pipes and tighten the flare nut as much as possible with your fingers. Then tighten the nut with a
wrench and torque wrench as shown in the figure.
CAUTION
• Do not apply excessive force. Otherwise, the nut may break.
Outer diameter of copper pipe
φ6.35 mm
φ9.52 mm
φ12.7 mm
• Tightening torque for connection of flare pipe
The pressure of R410A is higher than R22. (Approx. 1.6 times.) Therefore securely
tighten the flare pipes which connect the outdoor unit and the indoor unit with the
specified tightening torque using a torque wrench.
If any flare pipe is incorrectly connected, it may cause not only a gas leakage but also trouble in the refrigeration cycle.
R410A tool used
0 to 0.5
0 to 0.5
0 to 0.5
Imperial (Wing nut type)
Outer diameter of copper pipe
6.35
9.52
12.7
Outer diameter of copper pipe
6.35
9.52
12.7
Half union
Externally threaded side
Use a wrench to secure.
Tightening torque
14 to 18 (1.4 to 1.8 kgf·m)
33 to 42 (3.3 to 4.2 kgf·m)
50 to 62 (5.0 to 6.2 kgf·m)
Roughness
Obliquity
R410A
Flare nut
Internally threaded side
Use a torque wrench to tighten.
(Unit: N·m)
13
Warp
Conventional tool used
1.0 to 1.5
1.0 to 1.5
1.0 to 1.5
R410A
1.5 to 2.0
1.5 to 2.0
2.0 to 2.5
+0
B
–0.4
R22
9.1
9.0
13.2
13.0
16.6
16.2
Flare at indoor
unit side
Flare at outdoor unit
side
EN