Toshiba RAS-10N3AV2-A Service Manual page 65

10-4-3. Refrigerant Piping Connection
<Flaring>
1. Cut the pipe with a pipe cutter.
90˚
Fig. 10-4-4
2. Insert a flare nut into the pipe, and flare the pipe.
• Projection margin in flaring : A (Unit : mm)
Rigid (Clutch type)
Outer dia. of R410A
copper pipe tool used
∅ 6.35
0 to 0.5
∅ 9.52
0 to 0.5
∅ 12.7
0 to 0.5
Imperial (Wing nut type)
Outer dia. of
R410A
copper pipe
∅ 6.35
1.5 to 2.0
∅ 9.52
1.5 to 2.0
∅ 12.7
2.0 to 2.5
Die
Fig. 10-4-5
Obliquity Roughness Warp
Conventional
tool used
1.0 to 1.5
1.0 to 1.5
1.0 to 1.5
A
Pipe
<Tightening 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.
Half union
Externally
threaded side
Use a wrench
to secure.
• Do not apply excessive force.
Otherwise, the nut may break.
Outer dia. of copper pipe
Ø6.35 mm
Ø9.52 mm
Ø12.7 mm
• Tightening torque of connection of flare pipe connections
The operating pressure of R410A is higher than that
of R22 (Approx. 1.6 times.) It is therefore necessary
to firmly tighten the flare pipe connecting
sections (which connect
the indoor and outdoor units)
up to the specifed tightening
torque. Incorrect
connections may
cause not only a
gas leakage, but also damage to
the refrigeration cycle.
– 64 –
FILE NO. SVM-13001
Flare nut
Internally
threaded side
Use a torque wrench
to tighten.
Fig. 10-4-6
CAUTION
(Unit : N·m)
Tightening torque
16 to 18 (1.6 to 1.8 kgf•m)
30 to 42 (3.0 to 4.2 kgf•m)
50 to 62 (5.0 to 6.2 kgf•m)
Flare at
indoor unit
side
Flare at
outdoor unit
side
Fig. 10-4-7