Daikin VRV II Series - Page 175

Si39-303 Refrigerant Piping
Installation Manual 169
Caution Be sure to use the attached pipe when carrying out piping work in the field.
Be sure that the local piping does not touch other pipes, the bottom panel or side panel.
Especially for the bottom and side connection, be sure to protect the local piping with the
provided insulation, to prevent it from coming into contact with the casing.
Precautions when knocking out knock holes
!
Be sure to avoid damaging the casing
!
After knocking out the holes, we recommend you paint the edges and areas around the
edges using the repair paint to prevent rusting.
!
When passing electrical wiring through the knock holes, wrap the wiring with protective tape
to prevent damage.
!
Open knock holes around the 4 concave knock holes in the base frame, using a
φ
6mm-bit
drill.
2. Make sure to perform the piping installation within the range of the maximum allowable pipe
length, allowable level difference and allowable length after branching as indicated in
chapter “Example of connection”
3. For installation of the refrigerant branching kit, refer to the installation manual delivered with
the kit.
Mount the REFNET joint so that it branches either horizontally or vertically.
Mount the REFNET header so that it branches horizontally.
4. Pipe connection
•
Only use the flare nuts included with the unit.
Using different flare nuts may cause the refrigerant to leak.
•
Be sure to perform a nitrogen blow when brazing.
(Brazing without performing nitrogen replacement or releasing nitrogen into the piping will
create large quantities of oxidized film on the inside of the pipes, adversely affecting
valves and compressors in the refrigerating system and preventing normal operation.)
•
Do not use a flux when brazing the refrigerant pipe joints.
Use phosphor copper brazing (BCup) which does not require flux.
(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.)
Notes:
!
The pressure regulator for the nitrogen released when doing the brazing should be set to
0.02 MPa(0.2kg/cm
2
) or less.
1.Refrigerant piping
2.Location to be brazed
3.Nitrogen
4.Taping
5.Manual valve
6.Regulator
7.Nitrogen
Knock hole
Drill
Concave section
A
1
A-arrow diagram
2
1. Horizontal wires
2. Up to ±30× or vertically.
B
3
B-arrow diagram
3. Horizontal wires
1
2
4
5
6
3
7