Hitachi AirCore 700 Installation & Maintenance Manual page 19

3. Processing of refrigerant piping
•
Pipe cutting
Cut the copper pipe correctly with a pipe cutter.
•
Burrs removal
Completely remove all burrs from the cross
section of the pipe.
Put the end of the copper pipe downward to
prevent burrs from dropping in the pipe.
•
Putting nut on
Remove flare nuts attached to indoor and outdoor
units, then put them on burrs removed pipe.
(Not possible to put them on after flaring work).
Flare nut for pipe depends on the diameter of pipe.
•
Flaring work
Perform flaring work with flaring tool as shown below.
•
Check
Compare the flared work with the figure below.
If flare is noted to be defective, cut off the flared section and perform flaring work again.
Good
o
90
Burr Copper pipe
Spare
reamer
Pipe
cutter
4. Piping connection
•
Confirm that the valve is closed
•
Connect the indoor unit and the outdoor unit with field-supplied
refrigerant piping. Suspend the refrigerant piping at certain points
and prevent the refrigerant piping from touching the weak part of
the building such as wall, ceiling, etc. (If touched, abnormal sound
may occur due to the vibration of the piping. Pay special attention
in case of short piping length.)
•
Tighten the flare nut with two spanners as shown in the right figure.
•
Apply the refrigerant oil (field-supplied) thinly at the seat surface of
the flare nut and pipe before connecting and tightening. And when
tightening the flare nut, use two spanners.
•
Outdoor refrigerant piping should be connected with stop valve.
•
After finishing connecting the refrigerant pipes, keep it warm with
the insulation material as shown in the right figure.For outdoor
unit side, surely insulate every piping including valves. Cover
piping joints with pipe cover.
Using piping tape, apply taping starting from the entry of outdoor unit.
Flaring tool
No good
Tilted Uneven Burred
Flare nut
Copper pipe
-15-
4. Installation Instructions
90 º + 2 º
ØA
0.4 ~ 0.8R
Ød
Clutch type
Inside is shining without any scratches
Yoke
Die
Flare Copper
Copper pipe
nut
pipe
φ15.88mm
(Unit: mm)
Diameter
+0
A
φd
-0.4
6.35 9.1
9.53 13.2
12.7 16.6
15.88 19.7
Wing nut type
Smooth all
around
Die
Use two wrenches as shown
Double spanner work
Tube size Torque (N•m)
φ6.35mm 20
φ9.52mm 40
φ12.7mm 60
80