Connecting The Refrigerant Piping; About Connecting The Refrigerant Piping; Precautions When Connecting The Refrigerant Piping; Pipe Bending Guidelines - Daikin Sky Air Advance Series Installer's Reference Manual

6.4

Connecting the refrigerant piping

6.4.1

About connecting the refrigerant piping

Before connecting the refrigerant piping
Make sure the outdoor and indoor unit are mounted.
Typical workflow
Connecting the refrigerant piping involves:
▪ Connecting the refrigerant piping to the outdoor unit
▪ Connecting the refrigerant piping to the indoor units (see the
installation manual of the indoor units)
▪ Connecting refrigerant branch kits
▪ Keeping in mind the guidelines for:
▪ Pipe bending
▪ Brazing
▪ Using the stop valves
▪ Removing pinched pipes
6.4.2 Precautions when connecting the
refrigerant piping
INFORMATION
Also read the precautions and requirements in the
following chapters:
▪ General safety precautions
▪ Preparation
DANGER: RISK OF BURNING
CAUTION
NEVER install a drier to this unit to guarantee its lifetime.
The drying material may dissolve and damage the system.
NOTICE
Take the following precautions on refrigerant piping into
account:
▪ Avoid anything but the designated refrigerant to get
mixed into the refrigerant cycle (e.g. air).
▪ Only use R32 when adding refrigerant.
▪ Only use installation tools (e.g. manifold gauge set) that
are exclusively used for R32 installations to withstand
the pressure and to prevent foreign materials (e.g.
mineral oils and moisture) from mixing into the system.
▪ Protect the piping as described in the following table to
prevent dirt, liquid or dust from entering the piping.
▪ Use caution when passing copper tubes through walls.
Unit Installation period
Outdoor unit >1 month
<1 month
Indoor unit Regardless of the
period
INFORMATION
Do NOT open the refrigerant stop valve before checking
the refrigerant piping. When you need to charge additional
refrigerant it is recommended to open the refrigerant stop
valve after charging.
RZA200+250D7Y1B
Sky Air Advance-series
4P573383-1 – 2019.04
6.4.3
Use a pipe bender for bending. All pipe bends should be as gentle
as possible (bending radius should be 30~40 mm or larger).
6.4.4
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 (see
view A) or vertically.
A
6.4.5
▪ When brazing, blow through with nitrogen to prevent creation of
large quantities of oxidised film on the inside of the piping. This
film adversely affects valves and compressors in the refrigerating
system and prevents proper operation.
▪ Set the nitrogen pressure to 20 kPa (0.2 bar) (just enough so it
can be felt on the skin) with a pressure-reducing valve.
a
▪ Do NOT use anti-oxidants when brazing pipe joints.
Residue can clog pipes and break equipment.
▪ Do NOT use flux when brazing copper-to-copper refrigerant
piping. Use phosphor copper brazing filler alloy (BCuP), which
does not require flux.
Flux has an extremely harmful influence on refrigerant piping
systems. For instance, if chlorine based flux is used, it will cause
pipe corrosion or, in particular, if the flux contains fluorine, it will
deteriorate the refrigerant oil.
Protection method
▪ Always protect the surrounding surfaces (e.g. insulation foam)
Pinch the pipe
from heat when brazing.
Pinch or tape the pipe
6.4.6
To handle the stop valve
Take the following guidelines into account:
▪ Make sure to keep all stop valves open during operation.
▪ The gas and liquid stop valves are factory closed.
▪ The figures below show the name of each part required in
handling the stop valve.

Pipe bending guidelines

To connect the refrigerant branching kit

c
a
a Horizontal surface
b Refnet joint mounted vertically
c Refnet joint mounted horizontally

To braze the pipe end

b c d
f
a Refrigerant piping
b Part to be brazed
c Taping
d Manual valve
e Pressure-reducing valve
f Nitrogen

Using the stop valve and service port

6 Installation
b
e
f
Installer reference guide
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