Fujitsu AIRSTAGE J-IIIL Design & Technical Manual page 552

• Calculation of additional charge refrigerant
– Calculation of additional amount for pipe length (A)
Diameter of liquid pipe
in (mm)
Ø1/2 (12.70)
Ø3/8 (9.52)
Ø1/4 (6.35)
A = (0.077 lb × 49 ft) + (0.039 lb × 180 ft) + (0.014 lb × 269 ft) = 14.559 (lb)
A = (0.114 kg × 15 m) + (0.058 kg × 55 m) + (0.021 kg × 82 m) = 6.622 (kg)
– Calculation of factory charge amount (B)
Outdoor unit
B = 24.25 lb (11.0 kg)
– Total refrigerant amount check (C)
C = A + B = 14.559 + 24.25 = 38.809 (lb) < 44.09 (lb) → OK
C = A + B = 6.622 + 11.0 = 17.622 (kg) < 20 (kg) → OK
Check pipe length and height difference between the units by comparing with
page 06-17.
2-6. Piping design example
Additional amount for pipe
1
length
lb/ft (kg/m)
0.077 (0.114)
0.039 (0.058)
0.014 (0.021)
Model name
AOU72RLAVL
- (06-30) -
Liquid pipe length
ft (m)
49 (15)
180 (55)
269 (82)
Factory charge amount
24.25 lb (11.0 kg)
"Piping limitation" on
2. Piping design