31
• When doing the flare connection, please do the following: When connecting the expanding
pipes, fasten the pipes with double spanners. The torque refers to the former info.
• The connection of outdoor gas pipe and the refrigerant distributing pipe, as well as the
connection of refrigerant distributing pipe and the branch pipe should be welded with hard
solder.
• Charge nitrogen when brazing the pipe, or it will cause a number of impurities (a film of
oxidation) to clog the capillary and the expansion valve, further cause the deadly failure.
• When doing the braze connection, please do the following: Charge nitrogen when brazing the
pipe, or it will cause a number of impurities (a film of oxidation) to clog the capillary and the
expansion valve, further cause the deadly failure.
Operation procedure
• Protect the pipe end against the water and impurity going into the pipes (brazing after being
flatted, or sealed with adhesive tape).
• When connecting the pipes, close the valves fully.
• When welding the valve and the pipes, use the wet cloth to cool down the valve and the pipes.
• The refrigerant pipe should be clean. The nitrogen should be charged under the pressure
of about 0.5MPa and when charging the nitrogen, stop up the end of the pipe by hand to
enhance the pressure in the pipe, then loose the hand (meanwhile stop up the other end).
Pipe outer
diameter
(mm)
A
6.35
9.1
9.52
13.2
12.7
16.6
15.88
19.7
Expanding pipe:A(mm)
Pipe outer
diameter
(mm)
When it is hard pipe
Special tool
for R-410A
The former
tool
6.35
0-0.5
1.0-1.5
9.52
12.7
15.88
Projecting length of pipe to be expanded:B(mm)
Installation procedure
Seal the pipe end with adhesive tape or the stopper to
increase the resistance, fill up the pipe with nitrogen.
Only nitrogen gas
can be used
brazing
<N2>
taping
flat
brazing
adhesive tape
1st side
hand
2nd side
source valve
0.2MPa
