Fig. 5-7
Fig. 5-9
Fig. 5-10
Note the precautions when connecting the
field piping for the refrigerant. Add brazing
material.
Use the attached piping fittings when working
on the pipeline engineering on site.
After installation, make sure the piping does
not come in contact with each other, or the
chassis.
NOTE
5.4.3 Outdoor refrigerant connecting pipe
position
5.4.4 Connecting refrigerant piping to
outdoor unit
5.4.5 Connecting VRF piping assembly
5.4.6 Brazing
5.4.7 Connect stop valves
The wrong installation will cause the unit to
malfunction.
CAUTION
During brazing, use nitrogen as protection to prevent
the formation of a large amount of oxide film in the
pipes. This oxide film will have adverse effects on the
valves and compressors in the cooling system, and
may hamper normal operations.
Use the reducing valve to set the nitrogen pressure
to 0.02~0.03 Mpa (a pressure that can be felt by the
skin).
Do not use antioxidants when brazing the pipe joints.
Use copper-phosphorus alloys (BCuP) when brazing
copper and copper, and no flux is required. When
brazing copper and other alloy, flux is required.
Flux produces an extremely harmful effect on the
refrigerant piping system. For example, using a
chlorine-based flux is used may corrode the pipes,
and when the flux contains fluorine, it will degrade
the frozen oil.
The following figure shows the names of all parts
required for the installation of the stop valves.
Stop valves are closed when unit is shipped from the
factory. Do not open any stop valves until it is ready
to start the system with all of the pre-commissioning
checks have been completed.
The stop valve
The outdoor refrigerant connecting pipe position is
shown in the following figure.
The fittings provided as accessories can be used to
complete the connection from the stop valve to the field
piping.
When there are multiple outdoor units, the branch joints
must not be higher than the refrigerant piping as shown
below:
The branch joints should be as level as possible, and the
angular error does not exceed 10°.
8~12HP
14~18HP
U type branch joint
A-direction view
Error
Level
Correct
A
10°
10°
Fig. 5-8
Nitrogen
Oxygen
Brazing part
Copper pipe,
+
Copper pipe,
fittings
Packless valve
Copper pipe
Pipe interface
fittings for
nitrogen filling
High pressure
hose for nitrogen
filling
20
