Fujitsu AUYG18LVLB, Design & Technical Manual

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4. Place the branch pipe in a horizontal position as far as possible.
a. Only place the branch pipe as shown below during unavoidable circumstances.
Liquid Gas
Horizontal
position
Horizontal
position
b. When connecting the main piping, do not bend it near the connection section. If the main
pipe must be bent due to unavoidable circumstances, ensure that the linear section is 10
times or more than the diameter of the connection piping.
Liquid Gas
To indoor unit To indoor unit
Main pipe Main pipe
Straight pipe =
(D x 10) or more
Straight pipe =
(D x 10) or more
To outdoor unit
ØD
ØD
R
R
To outdoor unit
To indoor unit
To indoor unit
5. Welding the piping
Check that the connection piping is securely inserted into the branch pipe before welding.
CAUTION
• During piping work, apply nitrogen gas while brazing the pipes. If pipes are brazed without ap-
plying nitrogen gas, it will create a large amount of oxidation film, which will cause a critical mal-
function.
• To prevent moisture or foreign matter from entering during work, do not leave the piping open.
• Refer to installation manual supplied with the outdoor unit for sealing test evacuation proce-
dures.
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3-4. Branch pipes 3. Pipe installation
SYSTEM DESIGN SYSTEM DESIGN