Pipe outside diam-
Width across fl ats
4.3.2. Bending pipes
•
The pipes are shaped by your hands or pipe bender. Be careful not to collapse them.
•
Do not bend the pipes in an angle more than 90°.
•
When pipes are repeatedly bend or stretched, the material will harden, making it diffi cult
to bend or stretch them any more. Do not bend or stretch the pipes more than 3 times.
To prevent breaking of the pipe, avoid sharp bends.
If the pipe is bent repeatedly at the same place, it will break.
4.3.3. Pipe connection
• The gas and liquid pipes connections must be brazed.
• Be sure to braze them before performing any wiring work or installing the drain pipe.
Connection Pipe (Liquid)
Connection Pipe (Gas)
Rear Panel
Control Box
Maintenance Panel
Safety drain pan
When the fl are nut is tightened properly by your hand, hold the body side coupling with a
separate spanner, then tighten with a torque wrench.
• Hold the torque wrench at its grip, keeping it in the right angle with the pipe, in order
to tighten the fl are nut correctly.
Tighten with 2 wrenches.
Torque wrench
Indoor unit pipe
(Body side)
Connection pipe
Be sure to install the pipe against the port on the indoor unit and the outdoor unit
correctly. If the centering is improper, the fl are nut cannot tightened smoothly. If the
fl are nut is forced to turn, the threads will be damaged.
Do not remove the flare nut from the indoor unit pipe until immediately before
connecting the connection pipe.
Do not use mineral oil on fl ared part. Prevent mineral oil from getting into the system
as this would reduce the lifetime of the units.
En-5
9365748145-01_IM.indb Sec1:5
9365748145-01_IM.indb Sec1:5
Width across fl ats of
eter [mm (in.)]
Flare nut [mm]
6.35 (1/4)
17
9.52 (3/8)
22
12.70 (1/2)
26
15.88 (5/8)
29
19.05 (3/4)
36
CAUTION
Outer diameter of pipe
12.70 mm
22.22 mm
Connection Pipe
(Gas)
Connection Pipe
(Liquid)
CAUTION
Holding wrench
Flare nut
CAUTION
Flare nut [mm (in.)]
6.35 (1/4) dia.
9.52 (3/8) dia.
12.70 (1/2) dia.
15.88 (5/8) dia.
19.05 (3/4) dia.
1
WARNING
Be sure to use wet cloth, etc., to protect the pipe rubber, pipe heat insulation, and
the heat insulation of the safety drain pan as shown below. Because these parts are
extremely fl ammable, they can cause a fi re if they are not properly protected.
The heat exchanger contains a thermistor.
Do not expose the thermistor to the fl ame.
Protect these areas with wet cloth, etc.
Completely cover the pipe rubber
and pipe heat insulation with wet
cloth, etc., to prevent them from
burning.
Do not expose the unit (control box, rear panel, maintenance panel, etc.) and the inlet
grille to the fl ame. The exposure of these parts to the fl ame will adversely affect their
appearance and functions or cause a fi re.
CAUTION
If air or another type of refrigerant enters the refrigeration cycle, the internal pressure
in the refrigeration cycle will become abnormally high and prevent the unit from
exerting its full performance.
Apply nitrogen gas while
brazing the pipes. Nitrogen
gas pressure:
0.02 MPa (= pressure felt
sufficiently on the back of
your hand)
Brazing area
If a pipe is brazed without applying nitrogen gas, it will create an oxidation fi lm.
This can degrade performance or damage the parts in the unit (such as the
compressor or valves).
Do not use fl ux to braze pipes. If the fl ux is the chlorine type, it will cause the pipes to
corrode. Furthermore, if the fl ux contains fl uoride, it will adversely affect the refrigerant
pipe system such as by degrading the refrigerant oil.
For brazing material, use phosphor copper that does not require fl ux.
Tightening torque [N·m (kgf·cm)]
16 to 18 (160 to 180)
32 to 42 (320 to 420)
49 to 61 (490 to 610)
63 to 75 (630 to 750)
90 to 110 (900 to 1,100)
Pipe heat insulation
Pipe rubber
Brazing
Pipe rubber
Pipe heat insulation
Pressure regulating valve
Cap
Nitrogen gas
7/12/2012 11:09:12 AM
7/12/2012 11:09:12 AM