6
English
CAUTION
Follow the points at below.
•
Use a pipe cutter and flare suitable for the type of refrigerant.
•
Apply ester oil or ether oil to the flare section when using a
flare connection.
•
Only use the flare nuts included with the unit. Using different
flare nuts may cause the refrigerant to leak.
•
To prevent dust, moisture or other foreign matter from infil-
trating the piping, either pinch the end or cover it with tape.
•
Do not allow anything other than the designated refrigerant
to get mixed into the refrigerant circuit, such as air, etc. If any
refrigerant gas leaks while working on the unit, ventilate the
room thoroughly right away.
(1) Connect the piping.
•
The outdoor unit is charged with refrigerant.
•
Be sure to use both a spanner and torque wrench together,
as shown in the drawing, when connecting or disconnecting
pipes to/from the unit.
(Refer to the left picture below)
•
Refer to Table 1 for the dimensions of flare nut spaces.
•
Apply ester oil or ether oil to flare section (both inside and
out) when using flare nut connections and then turn 3 or 4
times by hand.
(Refer to the right picture above)
•
Refer to Table 1 for tightening torque.
Table 1
CAUTION
Overtightening may damage the flare and cause leaks.
Be careful for oil not to adhere to any portions other
than a flare part. If oil adheres to resin parts etc., there
is a possibility of damaging by deterioration.
•
Refer to Table 2 if no torque wrench is available.
Using a wrench to tighten flare nuts causes the tightening
torque to suddenly grow much tighter after a certain point.
From there, tighten the nut further by the appropriate angle
listed in Table 2.
(2) After the work is finished, make sure to check that
there is no gas leak.
(3) After checking for gas leaks, be sure to insulate the
pipe connections referring to the following picture.
•
Insulate using the insulation for fitting (3) (4) included with
the liquid and gas pipes. Besides, make sure the insula-
tion for fitting (3) (4) on the liquid and gas piping has its
seams facing up.
(Tighten both edges with clamp (9).)
•
For the gas piping, wrap the mid. sealing pad (6) over the
insulation for fitting (4) (flare nut part).
CAUTION
Be sure to insulate any field piping all the way to the piping
connection inside the unit. Any exposed piping may cause
condensation or burns if touched.
•
When brazing the refrigerant piping, perform nitrogen
replacement first, or perform the brazing (CAUTION 2) while
feeding nitrogen into the refrigerant piping (CAUTION 1), and
finally connect the indoor unit using the flare connections.
(Refer to the picture below)
CAUTION
1. When brazing a pipe while feeding nitrogen inside the
pipe, make sure to set the nitrogen pressure to 0.02 MPa
(0.2 kg/cm
2
) using the pressure reducing valve. (This
pressure is such that breeze is blown to your cheek.)
2. Do not use a flux when brazing the refrigerant pipe joints.
Use phosphor copper brazer (BCuP-2: JIS Z 3264/B-
Cu93P-710/795: ISO 3677) which does not require flux.
(Using a flux containing chlorine may cause the piping to
corrode. Using a welding flux containing fluorine may
cause the refrigerant lubricant to deteriorate, and affect
adversely the refrigerant piping system.)
Not recommendable but in case of emergency
You must use a torque wrench but if you are obliged to install the
unit without a torque wrench, you may follow the installation
method mentioned below.
After the work is finished, make sure to check that there is
no gas leak.
Pipe
size
Tightening torque
Flare dimen-
sion A (mm)
Flare shape
φ
6.4
15 – 17 N·m
8.7 – 9.1
φ
9.5
33 – 39 N·m
12.8 – 13.2
φ
12.7
50 – 60 N·m
16.2 – 16.6
φ
15.9
63 – 75 N·m
19.3 – 19.7
Flare nut
Piping union
Ester oil or ether oil
Spanner
Torque wrench
A
45
0
Ⳳ
2
0
R0.4-0.8
90
0
Ⳳ
2
0
Main unit
Wrap over the top of the
flare nut connection.
(accessory)
(accessory)
Insulation for fitting (3)
(accessory)
Liquid pipe
Main unit
Attach to base
Piping insulation material
(main unit)
Piping insulation material
(Field supply)
Turn seams up
Flare nut connection
Clamp (9) (accessory)
Piping insulation material
(Field supply)
Clamp (9)
(accessory)
Liquid Piping Insulation Procedure
Gas Piping Insulation Procedure
Insulation for fitting (4)
Mid. sealing pad (6)
Turn seams up
Flare nut connection
Attach to base
Piping insulation
material (main unit)
Gas pipe
Nitrogen
Nitrogen
Hands
valve
Pressure-reducing valve
Taping
Part to be brazed
Refrigerant piping
