Fujitsu AJ 126LELDH Series Design & Technical Manual page 746

• Selection of pipe size
Pipe no.
a
b
b1
c
d
e1
e2
f1
f2
f3
*: When the length of the pipe between outdoor unit and the first separation tube or header is
greater than 70 m, liquid pipe must be size up from 9.52 mm to 12.70 mm.
For details, refer to
• Limitation check
Total pipe length
Between outdoor unit and farthest indoor
unit
Between the first separation tube and the
farthest indoor unit
Between outdoor unit and the nearest
indoor unit
Between outdoor unit and the first
separation tube
• Calculation of additional charge refrigerant
– Calculation of additional amount for pipe length (A)
Diameter of liquid pipe (mm)
Ø12.70
Ø9.52
Ø6.35
A = (0.114 kg × 80 m) + (0.058 kg × 20 m) + (0.021 kg × 30 m) = 10.91 (kg)
– Calculation of factory charge amount (B)
Outdoor unit
B = 7.5 kg
– Total refrigerant amount check (C)
C = A + B = 10.91 + 7.5 = 18.41 (kg) < 20.0 (kg) → OK
Check pipe length and height difference between the units by comparing with
page 06-17.
2-6. Piping design example
Liquid pipe
Ø12.70
Ø12.70
Ø9.52
Ø9.52
Ø9.52
Ø6.35
Ø6.35
Ø6.35
Ø6.35
Ø6.35
"Pipe size selection"
Pipe
Additional amount for pipe
1
Pipe diameter (mm)
Gas pipe
Ø22.22
Ø22.22
Ø15.88
Ø15.88
Ø15.88
Ø12.70
Ø12.70
Ø9.52
Ø9.52
Ø9.52
on page 06-22.
Example
Diagram
Total 155
a + b + c + f3 110
b + c + f3
a + b1
a
length (kg/m)
0.114
0.058
0.021
Model name
AJ090LELDH
- (06-32) -
Length example
Limitation
m
400
or less
120
or less
90
30
or less
5
90
or more
3
75
or more
Liquid pipe length (m)
80
20
30
Factory charge amount (kg)
7.5
"Piping limitation"
(m)
75*
5
10
5
5
10
5
5
5
5
Judge
OK
OK
OK
OK
OK
on
2. Piping design