English
5
CAUTION
Over-tightening may damage the flare and cause a
refrigerant leakage.
Use “ Table 3 ” as a reference if a torque wrench is not available.
Once work is complete, make sure there is no gas leaking. As
the flare nut is tightened with the wrench, the torque will
suddenly increase. From that position, tighten the nut to the
angle shown on “ Table 3 ”.
The turning torque of the hexagon head bolts (Accessory) to
connect the attached pipe (Accessory) to the unit is 21.5 –
28.9 N·m.
• After checking the pipe-connection for gas leakage, be sure
to insulate the liquid and gas piping, referring to the figure
below.
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.
NOTE
• Attached piping is needed for connecting gas piping.
When connecting the included piping, use the included
piping flange hex bolts (2) and spring washers (2).
• Connect refrigerant piping and branching according to the
attached installation manuals that come with the outdoor
unit.
CAUTION
CAUTION TO BE TAKEN WHEN BRAZING
REFRIGERANT PIPING
Do not use flux when brazing refrigerant piping. Therefore,
use the phosphor copper brazing filler metal (BCuP-2: JIS Z
3264/B-Cu93P-710/795: ISO 3677) which does not require
flux.
(Flux has extremely harmful influence on refrigerant piping
systems. For instance, if the chlorine based flux is used, it
will cause pipe corrosion or, in particular, if the flux contains
fluorine, it will damage the refrigerant oil.)
• Before brazing local refrigerant piping, nitrogen gas shall be
blown through the piping to expel air from the piping.
If your brazing is done without nitrogen gas blowing, a large
amount of oxide film develops inside the piping, and could
cause system malfunction.
• When brazing the refrigerant piping, only begin brazing after
having carried out nitrogen substitution or while inserting
nitrogen into the refrigerant piping. Once this is done,
connect the indoor unit with a flared or a flanged connection.
• Nitrogen should be set to 0.02 MPa with a pressure-reducing
valve if brazing while inserting nitrogen into the piping.
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.
When you keep on tightening the flare nut with a spanner,
there is a point where the tightening torque suddenly
increases. From that position, further tighten the flare nut
the angle shown below:
Table 3
Apply ester oil or ether oil only inside
Torque wrench
Spanner
Piping union
Flare nut
!
Indoor units to be
connected
Gas piping diameter
Liquid piping
diameter
FXTQ80
φ
19.1
Use attached piping.
φ
9.5
FXTQ100
φ
22.2
Use attached piping.
φ
9.5
Pipe size
Further tightening
angle
Recommended arm length of
tool
φ
9.5 (3/8”)
60 to 90 degrees
Approx. 200mm
φ
12.7 (1/2”)
30 to 60 degrees
Approx. 250mm
φ
15.9 (5/8”)
30 to 60 degrees
Approx. 300mm
Nitrogen
Refrigerant
piping
Part to be
brazed
Taping
Pressure-reducing valve
Hands
valve
Nitrogen
4PEN408655-1B_2016_02.book Page 5 Friday, February 19, 2016 1:33 PM
