GB - 5
38VYX110/38VYX130
E N G L I S H
Refrigerant piping
Flaring
1. Cut the pipe with a pipe cutter.
2. Insert a flare nut into the pipe, and flare the pipe.
As the flaring sizes of R410A differ from those of refrigerant
R22, the flare tools newly manufactured for R410A are
recommended.
Table V: Pipe outer diameter
• 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 to
the specified flare size.
The copper pipe gauge is useful for adjusting projection
margin size.
A
B
Flare at indoor
unit side
Flare at outdoor
unit side
Align the centres of the connecting pipes and tighten the flare nut
as strong as possible with your fingers.
Then fix the nut with a spanner and tighten it with torque wrench as
shown in the figure.
• As shown in the figure, use two spanners to unscrew or tighten
the valve flare nut, at gas side.
If using a single spanner, the nut cannot be tightened with
necessary tightening torque.
On the contrary, use a single spanner to loosen or tighten the
flare nut of the valve at liquid side.
REQUIREMENT:
1. Do not put the spanner on the cap. The valve may be broken.
2. If applying excessive torque, the nut may be broken
according to some installation conditions.
• After the installation work, be sure to check gas leak of
connecting part of the pipes with nitrogen.
• Pressure of R410A is higher than that of R22 (Approx. 1.6
times).
Therefore, using a torque wrench, tighten the flare pipe
connecting sections which connect the indoor/outdoor units at
the specified tightening torque.
Incomplete connections may cause not only a gas leak, but
also a trouble of the refrigeration cycle.
IMPORTANT:
Do not apply refrigerating machine oil to the flared surface.
Cover
Half union or packed valve
Flare nut
Internally threaded side
Externally threaded side
C
D
C Fix with spanner.
D Tighten with torque wrench.
Cover
Piping valve
Flare nut
E Tightened
F Loosened
E
F
Outer dia. of copper pipe
A
+ 0
mm
-0,4
R410A
R22
9,52
13,2
13,0
15,87
19,7
19,4
90˚
Obliquity
Roughness
Warp
