Operation procedure
• Brazing the pipe at the same time charge the nitrogen. Or it will cause a number of impurity (a
fi
lm of oxidation) to clog the capillary and the expansion valve, further cause the deadly failure.
• Protect the pipe end against the water, impurity into the pipes (welding after being
fl
at, or
being sealed with adhesive tape).
• The refrigerant pipe should be clean. The nitrogen should
fl
ow 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).
• 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.
Seal the pipe end with adhesive tape or the stopper to
increase the resistance,
fi
ll up the pipe with nitrogen.
Only nitrogen gas
can be used
brazing
fl
at
brazing
adhesive tape
<N2>
taping
1st side
hand
2nd side
source valve
0.2MPa
• Since the unit is with R410A, the expanding oil is ester oil, not the mineral oil.
• When doing the
fl
are connection, please do the following: When connecting the expanding
pipe, fasten the pipes with double-spanner. The torque refers to the former info.
Pipe outer
diameter
(mm)
A
Ø6.35
9.1
Ø9.52
13.2
Ø12.7
16.6
Ø15.88
19.7
Expanding pipe:A(mm)
Pipe outer
diameter
(mm)
When it is hard pipe
Special tool
for R410A
The former
tool
Ø6.35
0-0.5
1.0-1.5
Ø9.52
Ø12.7
Ø15.88
Projecting length of pipe to be expanded:B(mm)
• The outdoor gas pipe and the refrigerant distributing pipe, as well the refrigerant distributing
pipe and the branch pipe should be welded with hard solder.
• When doing the braze connection, please do the following: Brazing the pipe at the same
time charge the nitrogen. Or it will cause a number of impurity (a
fi
lm of oxidation) to clog the
capillary and the expansion valve, further cause the deadly failure.
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