
10
English
•
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 Fig. 12)
•
Refer to “Table 1” for the dimensions of flare nut spaces.
•
When connecting the flare nut, coat the flare section (both inside and
outside) with ester oil or ether oil, rotate three or four times first, then
screw in.
(Refer to Fig. 13)
• Keep all the screw mounting resin parts (e.g., piping presser
plates) away from oil.
If oil adheres, the strength of the screw mounting resin parts may drop.
CAUTION
•
Over-tightening may cause the flare nuts to crack or the refrigerant
to leak.
NOTE
•
Use the flare nut included with the unit main body.
Table 1
•
Refer to Table 1 to determine the proper tightening torque.
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 2
After the work is finished, make sure to check that there is no gas leak.
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.)
Pipe size
Tightening torque
(N·m)
Flare dimensions A (mm)
Flare
φ
6.4 (1/4”)
14.2 – 17.2
8.7 – 9.1
φ
9.5 (3/8”)
32.7 – 39.9
12.8 – 13.2
φ
12.7 (1/2”)
49.5 – 60.3
16.2 – 16.6
φ
15.9 (5/8”)
61.8 – 75.4
19.3 – 19.7
Pipe size
Further tightening angle
Recommended arm length of tool
φ
6.4 (1/4”)
60 - 90 degrees
Approx. 150mm
φ
9.5 (3/8”)
60 - 90 degrees
Approx. 200mm
φ
12.7 (1/2”)
30 - 60 degrees
Approx. 250mm
φ
15.9 (5/8”)
30 - 60 degrees
Approx. 300mm
Fig. 13
Apply ester oil or
ether oil only inside
Torque wrench
Spanner
Piping union
Flare nut
Fig. 12
R0.4-0.8
A
90
0
±2
0
45
0
±2
0
01_EN_3P156215-12U.fm Page 10 Thursday, August 27, 2009 4:09 PM