Design and Technical Manual

6. SYSTEM DESIGN
PIPE SIZE2-3.
PIPE DIAMETER, RECOMMENDED MATERIAL AND WALL THICKNESS
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Nominal Diameter (in) 1/4" 3/8" 1/2" 5/8" 3/4"
Outside Diameter (mm) 6.35 9.52 12.70 15.88 19.05
Material JIS H3300 C1220T-O or equivalent *1
Wall Thickness *2 (mm) 0.8 0.8 0.8 1.0 1.2
*1: Allowable tensile stress ≥ 33 (N/mm
2
)
*2: Endurance pressure of the pipe must be 609 psi (4.2 MPa).
Please select the pipe size in accordance with local rules.
PIPE SIZE SELECTION
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Branch box 1
(Primary)
First
Separation
tube
Outdoor unit
Indoor units
Branch box 2
(Secondary)
Branch box 3
(Secondary)
Pipe size
table"A"
Pipe size
table"B"
Pipe size
table"C"
Pipe size
table"D"
Second
Separation
tube
- (06 - 14) -
SYSTEM DESIGN SYSTEM DESIGN