Daikin BSVQ36PVJU Installation Manual page 9

• Use the following items for the refrigerant piping.
Material: Jointless phosphor-deoxidized copper pipe
Size: See "Example of connection" to determine the correct size.
Thickness: Select a thickness for the refrigerant piping which complies with national and local laws.
For R410A, the design pressure is 478 psi.
• For information regarding the piping allowable maximum length, allowable height difference, and allowable
length after a branch, refer to the installation manual that came with the outside unit or Engineering data book.
• The refrigerant branch kit (sold separately) is required for piping branches. For information on how to select a
refrigerant branch kit, refer to the Installation Manual that came with the outside unit or Engineering data book.
6-2 PROTECTION AGAINST CONTAMINATION WHEN INSTALLING PIPES
Protect the piping to prevent moisture, dirt, dust, etc. from entering the piping.
Place Installation period
More than a month
Outdoor
Less than a month
Indoor Regardless of the period
NOTE
Exercise special caution to prevent dirt or dust when passing piping through holes in walls and when passing
pipe edges to the exterior.
6-3 PIPING CONNECTION WORK PRECAUTIONS
• When brazing refrigerant piping, begin working after replacing the nitrogen (*1) or perform brazing while
nitrogen is flowing in the refrigerant piping (*2) (Refer to Fig. 5), and at the end made the indoor unit and
BS unit flare or flange connections.
(*1) For details on nitrogen replacement, see the "VRV Installation Manual" (available at any Daikin dealer).
(*2) The pressure regulator for the nitrogen released when doing the brazing should be set to about
2.9 psi (Enough to feel a slight breeze on your cheek).
NOTES
• Do not use an anti-oxidizing agent when brazing the piping. Residual debris could clog the piping or cause
parts to malfunction.
• Do not use a flux when brazing the refrigerant pipe joints.
Using a chlorine flux may cause the pipes to corrode, and if it contains fluoride it may cause the refrigerant
lubricant to deteriorate, adversely affecting the refrigerant piping system.
Use phosphor copper brazing (B-Cu93P-710/795: ISO 3677) which does not require flux.
6-4 PIPING SIZE SELECTION
From Example of connection 1 and 2 below and Table 1, 2, select the piping size between the outside unit
(refrigerant branch kit) and BS unit, and between the BS unit and the indoor unit (refrigerant branch kit).
English
Pressure-reducing valve
Part to be brazed Taping
Nitrogen
Refrigerant piping
Fig. 5
Protection method
Pinch the pipe
Pinch or tape the pipe
Nitrogen
Valve
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