Toshiba RAS-B05BKVG-E Service Manual page 64

10-4-3. Refrigerant piping connection
<Flaring>
1. Cut the pipe with a pipe cutter.
90°
Fig. 10-4-3
2. Insert a flare nut into the pipe, and flare the pipe.
•
Projection margin in flaring : A (Unit : mm)
Die
Fig. 10-4-4
Ridgid (Clutch type)
Outer dia.
R32 tool used
of copper pipe
Ø6.35 0 to 0.5
Ø9.52 0 to 0.5
Ø12.70 0 to 0.5
Pipes thickness
Imper
ial (wing nut type)
Outer dia. of copper pipe
Ø6.35
Ø9.52
Ø12.70
Pipes thickness
CAUTION
• Do not scratch the inner surface of the flared part
when removing burrs.
• Flare processing under the condition of scratches
on the inner surface of fl are processing part will
cause refrigerant gas leak.
Roughness
Obliquity
A
Pipe
Conventional tool
used
1.0 to 1.5
1.0 to 1.5
1.0 to 1.5
0.8 mm or more
R32
1.5 to 2.0
1.5 to 2.0
2.0 to 2.5
0.8 mm or more
<Tightening connection>
Align the centers of the connecting pipes and tighten
the flare nut as far as possible with your fingers. Then
tighten the nut with a spanner and torque wrench as
shown in the figure.
Warp
Externally
threaded side
Use a wrench to secure.
CAUTION
• Do not apply excess torque.
•
Otherwise, the nut may crack depending on the
conditions.
Outer dia. of copper pipe
Ø6.35 mm
Ø9.52 mm
Ø12.70 mm
Tightening torque of flare pipe connections
The operating pressure of R32 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 specified tightening torque.
Incorrect connections may cause not only a gas
leakage, but also damage to the refrigerant cycle.
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FILE NO. SVM-18006
Half union Flare nut
Internally
threaded side
Use a torque wrench to tighten.
Fig. 10-4-5
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. 10-4-6
(Unit : N•m)