Daikin GYEQ20AN Service Manual page 53

SiAUY361411EA
7 Installing the Outdoor Unit
When braze-welding a copper pipe, be sure to blow with nitrogen (this is an absolute requirement for
braze welding).
Perform braze welding with nitrogen gas flowing through the copper pipe from one end to the other end.
Cover the end of the copper pipe from which you blow in the nitrogen with tape to prevent air from getting
sucked in. Braze welding without blowing nitrogen would generate oxide layers that might possibly clog the
unit during operating cycles, resulting in a serious accident.
• Nitrogen blow prevents the formation of oxide layers in copper pipes.
• Do not blow with other gases than nitrogen.
• Do not use an antioxidant which may adversely affect the
refrigerant or refrigerating machine oil.
Phosphor copper braze is recommended as brazing filler metal.
During installation or repair, do not use fire if the air contains refrigerant gas.
After the braze welding, wipe off flux with a damp cloth or similar.
Avoid the use of a (reverse) right-angled expansion pipe for installation. It can cause serious damage
to the compressor.
Use a double-ended spanner to tighten the flare nut, and finally use a torque wrench to make sure
that the nut is tightened with the appropriate torque. Take care not to overtighten and break the flare.
Hold the union side securely so that it will not turn.
Union
side
Spanner
Device Overview
Flare nut
side
022619-00E
Torque wrench
Copper pipe
– 14 –
Installation Work Manual
Brazing section
Nitrogen
Taping Valve
022618-00E
0FGHP-EN0801 DGJ002
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