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EN-13
EN-14
Refrigerant Piping Connection
CAUTION
TAKE NOTE OF THESE 4 IMPORTANT POINTS
BELOW FOR PIPING WORK
1.
Keep dust and moisture away from inside the
connecting pipes.
2.
Tightly connect the connection between pipes and
the unit.
3.
Evacuate the air in the connecting pipes using a
VACUUM PUMP.
4.
Check for gas leaks at connection points.
Piping connection
Flaring
1.
Cut the pipe with a pipe cutter.
Be sure to remove burrs that may cause a gas leak.
2.
Insert a flare nut into the pipe, and then flare the
pipe.
Use the flare nuts supplied with the air conditioner
or those for R410A.
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.
However, the conventional tools can be used by
adjusting the projection margin of the copper pipe.
Projection margin in flaring : B (Unit : mm)
Rigid (Clutch type)
Flaring diameter size : A (Unit : mm)
* In case of flaring for R410A with the conventional flare
tool, pull the tool out approx. 0.5 mm more than that
for R22 to adjust it to the specified flare size.
The copper pipe gauge is useful for adjusting the
projection margin size.
Liquid side
Outer diameter
Thickness
Ø9.5 mm
0.8 mm
Gas side
Outer diameter
Thickness
Ø15.9 mm
1.0 mm
Outer diam. of
copper pipe
R410A tool
used
Conventional
tool used
R410A
1.0 to 1.5
9.5
0 to 0.5
15.9
Outer diam. of copper
pipe
A
9.5
13.2
15.9
19.7
B
A
+0
–0.4
Tightening of Connecting Part
1.
Align the centers of the connecting pipes and fully
tighten the flare nut with your fingers. Then fix the
nut with a wrench as shown in the figure and tighten
it with a torque wrench.
2.
As shown in the figure, be sure to use two wrenches
to loosen or tighten the flare nut of the valve on the
gas side. If you use a single crescent, the flare nut
cannot be tightened to the required tightening
torque.
On the other hand, use a single crescent to loosen
or tighten the flare nut of the valve on the liquid side.
(Unit: N•m)
CAUTION
1.
Do not put the crescent wrench on the cap or cover.
The valve may break.
2.
If applying excessive torque, the nut may break
according to some installation conditions.
• After the installation work, be sure to check for gas
leaks of the pipe connections 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 that connect the indoor/
outdoor units at the specified tightening torque.
Incomplete connections may cause not only a gas
leak, but also trouble with the refrigeration cycle.
Outer dia. of copper pipe
Tightening torque
9.5 mm (diam.)
33 to 42 (3.3 to 4.2 kgf•m)
15.9 mm (diam.)
63 to 77 (6.3 to 7.7 kgf•m)
Half union or packed valve
Flare nut
Externally
threaded side
Internally
threaded side
Fix with wrench.
Tighten with torque wrench.
Cover
Piping valve
Tightened
Flare nut
Cap
Loosened
Valve at gas side
Do not apply refrigerant oil to the flared surface.
NO GOOD
Cover
Cap
