Daikin VRV FXAQ20MAVE, Installation Manual

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English 10
• Refer to Table 1 for tightening torque.
Table 1
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
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.)
• When brazing the refrigerant piping, only begin brazing after having carried out nitrogen substitution
(NOTE 1) or while inserting nitrogen into the refrigerant piping (NOTE 2). Once this is done, connect the
indoor unit with a flared or a flanged connection.
NOTES
1. Refer to the “Manual for Multi Installation for Buildings” for directions on how to carry out nitrogen
substitution. (Inquire with your dealer.)
2. Nitrogen should be set to 0.02 MPa with a pressure-reducing valve if brazing while inserting nitrogen into
the piping.
(Refer to Fig. 14)
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.
Pipe size Tightening torque
Flare dimensions A (mm)
Flare
FXA–LVE(C) FXAQ–M(A)VE
φ
6.4 (1/4”) 14.2 – 17.2N·m 8.6 – 9.0 8.7 – 9.1
φ
9.5 (3/8”) 32.7 – 39.9N·m 12.6 – 13.0 12.8 – 13.2
φ
12.7 (1/2”) 49.5 – 60.3N·m 15.8 – 16.2 16.2 – 16.6
φ
15.9 (5/8”) 61.8 – 75.4N·m 19.0 – 19.4 19.3 – 19.7
Pipe size Further tightening angle Recommended arm length of tool
φ
6.4 (1/4”) 60 to 90 degrees Approx. 150mm
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
R0.4-0.8
A
90
0
±2
0
45
0
±2
0
Refrigerant piping
Part to be
brazed
Taping
Pressure-reducing valve
hands valve
Nitrogen Fig. 14
Nitrogen
01_EN_3P156215-10P.fm Page 10 Wednesday, April 2, 2008 11:47 AM