Daikin VRV III BSVQ100P8V1B, Manual

8

English

6-2 PROTECTION AGAINST CONTAMINATION WHEN INSTALLING PIPES

Protect the piping to prevent moisture, dirt, dust, etc. from entering the piping.

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 

0.02 MPa (0.2kg/cm

2

: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 (BCuP-2: JIS Z 3264/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 outdoor unit 
(refrigerant branch kit) and BS unit, and between the BS unit and the indoor unit (refrigerant branch kit).

Example of connection 1: When 1 indoor unit is connected downstream from the BS unit

Place

Installation period

Protection method

Outdoor

More than a month

Pinch the pipe

Less than a month

Pinch or tape the pipe

Indoor

Regardless of the period

Refrigerant piping

Valve

Pressure-reducing valve

Part to be brazed

Taping

Nitrogen

Nitrogen

Fig. 5

To refrigerant branch 
kit or outdoor unit

*

Suction gas pipe

<Upstream>

<Downstream>

Gas pipe

Indoor unit

Liquid pipe

HP/LP gas pipe

Liquid pipe

Determine using Table 1 based 
on the total capacity of the indoor 
units connected downstream.

Select from Table 2 depending 
on the capacity type of the 
indoor unit.

BS

unit