6 Installation
Installer and user reference guide
23
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546228-1 – 2018.09
X
Not allowed
O
Allowed
▪ Make sure that the total length of the piping connected to the joint
is absolute straight for more than 500 mm. Only if a straight field
piping of more than 120 mm is connected, more than 500 mm of
straight section can be ensured.
>120 mm
>500 mm
6.4.6
Multiple outdoor units: Knockout holes
Connection
Description
Front connection
Remove the front plate knockout holes to
connect.
Bottom connection
Remove the knockout holes on the bottom
frame and route the piping under the bottom.
6.4.7
To connect the refrigerant branching kit
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.
A
B
±3
0
°
a
b
c
a
a
Horizontal surface
b
Refnet joint mounted vertically
c
Refnet joint mounted horizontally
6.4.8
To protect against contamination
Protect the piping as described in the following table to prevent dirt,
liquid or dust from entering the piping.
Unit
Installation period
Protection method
Outdoor unit
>1 month
Pinch the pipe
<1 month
Pinch or tape the pipe
Indoor unit
Regardless of the
period
Seal the piping and wiring intake holes using sealing material (field
supply), otherwise the capacity of the unit will drop and small
animals may enter the machine.
Example: passing piping out through the front.
a
a
Close the areas marked with "
". (When the piping is
routed from the front panel.)
▪ Only use clean pipes.
▪ Hold the pipe end downwards when removing burrs.
▪ Cover the pipe end when inserting it through a wall, to prevent
dust and/or particles entering the pipe.
6.4.9
To braze the pipe end
NOTICE
Precautions when connecting field piping. Add brazing
material as shown in the figure.
1
1
1
1
2
2
≤Ø25.4
>Ø25.4
▪ 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
c
d
e
f
f
a
Refrigerant piping
b
Part to be brazed
c
Taping
d
Manual valve
e
Pressure-reducing valve
f
Nitrogen
▪ Do NOT use anti-oxidants when brazing pipe joints.
Residue can clog pipes and break equipment.
