Pipe Bending Guidelines; To Braze The Pipe End - Daikin RXYSA4A7V1B Installer And User Manual

18 | Piping installation

18.2.3 Pipe bending guidelines

18.2.4 To braze the pipe end

Installer and user reference guide
82
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
Outdoor unit
Indoor unit
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.
Use a pipe bender for bending. All pipe bends should be as gentle as possible
(bending radius should be 30~40 mm or larger).
NOTICE
Precautions when connecting field piping. Add brazing material as shown in the
figure.
≤Ø25.4
1
1
▪ 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 b
f
a Refrigerant piping
b Part to be brazed
Installation period
>1 month
<1 month
Regardless of the period
c d e
f
Protection method
Pinch the pipe
Pinch or tape the pipe
RXYSA4~6A7V/Y1B
VRV 5-S system air conditioner
4P600330-1A – 2020.07