MovinCool Office Pro W20 Service Manual - Manual (Page 65)

Repair Section
65
(4) Use of dry nitrogen gas
• During brazing, the inside of the pipe undergoes an oxidative reaction due to the brazing flame.
Introduce dry nitrogen gas (0.27 gal/min (1 L/min); adjust with the flow regulator) through the
pinch-off tube of the refrigerant.
< NOTE >
Take care not to allow dirt, water, oil, etc. to enter into the pipe.
(5) Vertical Joint
• Heat the whole brazed fitting to a proper
brazing temperature. Bring the brazing filler
metal into contact with the fitting so that the
brazing filler metal starts flowing by itself.
• Stop heating the fitting as soon as the brazing
filler metal has flown into the clearance. Since
the brazing filler metal flows easily into the
portion heated to a proper temperature, it is
essential to keep the whole fitting at a proper
brazing temperature.
I000564
Burner
45°
Tube
Brazing Filler Metal
Vertical Down Joint
I001725
Burner
45°
Tube
Brazing Filler Metal
Vertical Up Joint