Panasonic U-72MF2U9 Installation Instructions Manual page 28

● Precautions for brazing
Be sure to replace the air inside the tube with nitrogen to prevent
oxide film from forming during the brazing process. Be sure to use
a damp cloth or other means to cool the valve unit during brazing.
Work method
Field-supply tube
Brazing locations
1. Be sure to use nitrogen. (Oxygen, CO
2. Use a pressure-reducing valve on the nitrogen tank.
CAUTION
3. Do not use agents intended to prevent the formation of oxide film.
4. The balance tube is not used if only 1 outdoor unit is installed.
Remote valve
Taping
They will adversely affect the refrigeration oil, and may cause equipment failure.
Use the unit in the same conditions as when it was shipped from the factory.
Pressure-reducing
valve (regulator)
, and CFC must not be used.)
2
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