<Tightening connection>
Align the centers of the connecting pipes and tighten
CAUTION
Do not apply excess torque.
Otherwise, the nut may crack depending on the
conditions.
•
•
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.
Flare nut
Half union
Use a wrench to secure.
Use a torque wrench to tighten.
Fig. 10-4-
7
Externally
threaded side
Internally
threaded side
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.
Fig. 10-4-
8
Flare at
indoor unit side
Flare at
outdoor unit side
(Unit : N
•
m)
Outer dia. of copper pipe
Ø6.35 mm
Ø9.52 mm
Ø12.7
0
mm
Tightening torque
1
6
to 18 (1.
6
to 1.8 kgf•m)
3
0
to 42 (3.
0
to 4.2 kgf•m)
50 to 62 (5.0 to 6.2 kgf•m)
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.
10-4-
4
. Refrigerant piping connection
<Flaring>
1. Cut the pipe with a pipe cutter.
Fig. 10-4-
5
2. Insert a flare nut into the pipe, and flare the pipe.
Projection margin in flaring : A (Unit : mm)
Fig. 10-4-
6
90
°
Roughness
Obliquity
A
Die
Pipe
Warp
•
ial (wing nut type)
Ridgid (Clutch type)
Imper
Outer dia.
of copper pipe
R32 tool used
Conventional tool
used
Ø6.35
0 to 0.5
1.0 to 1.5
Ø9.52
0 to 0.5
1.0 to 1.5
Ø12.70
0 to 0.5
1.0 to 1.5
Pipes thickness
0.8 mm or more
Outer dia. of copper pipe
R32
Ø6.35
1.5 to 2.0
Ø9.52
1.5 to 2.0
Ø12.70
2.0 to 2.5
Pipes thickness
0.8 mm or more
FILE NO. SVM-19004
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