AHU-KIT
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(1) Make sure there is nitrogen protection during welding.
Brazing without carrying out nitrogen replacement or releasing nitrogen into the piping will create large
quantities of oxidized film on the inside of the pipes, adversely affecting valves and compressors in the
refrigerating system and preventing normal operation.
(2) When brazing while inserting nitrogen into the piping, nitrogen must be set to 0.02 MPa with a
pressure-reducing valve (=just enough so that it can be felt on the skin).
1) Refrigerant piping
2) Part to be brazed
3) Taping
4) Hands valve
5) Pressure-reducing valve
6) Nitrogen
For details, see manual of the outdoor unit.
(3) Make sure to cool the filters and valve body with a wet cloth and make sure the body temperature does not
exceed 120°C(248
℉
) during brazing.
(4) Make sure that the other parts such as electrical box, tie wraps and wires are protected from direct brazing
flames during brazing.
(5) The EXV box is required to be installed in a vertical direction within the range of 90±15° (not allowed for
horizontal work). Welding the connection tubes first before refrigerant pipes in order to avoid face-down
soldering.
(6) All field piping must be provided by a licensed refrigeration technician and must comply with the relevant
local and national codes.
a)
For refrigerant piping of outdoor unit, refer to the installation manual supplied with the outdoor unit.
b)
The maximum allowed piping length depends on the connected outdoor model.
(4) Secure the wire clamp (C) in place again (6xM4.2).
(5) Make sure that field pipes are fully insulated. Make sure that there is no gap between
both ends in order to avoid condensation dripping (finish the connection with tape
eventually).
4.2.3 Installation handbook of the EXV cable
4.2.3.1.Installation steps
(1) Making the cable terminal through the Cable-Cross Loop ( Fig.4.2.2), and then winding
the cable on the magnetic ring for three times( Fig.4.2.3), at last inserting the terminal into
