Fujitsu Airstage J-II Series - Page 585

2-5. ADDITIONAL CHARGE CALCULATION
● The outdoor unit is charged refrigerant at the factory.
● Additional refrigerant required to be charged on site depending on pipe length.
● The additional refrigerant charge amount is calculated according to the following formula.
● Round up the calculated result to two decimal places.
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CALCULATION OF ADDITIONAL CHARGE REFRIGERANT
1. Calculation of additional amount for outdoor unit
Model Ton
b
Factory charged
amount [lbs. (kg)]
AOU36RLAVM 3 10.6 (4.80)
AOU48RLAVM 4 11.7 (5.30)
AOU60RLAVM 5 11.7 (5.30)
Diameter of liquid
pipe [in. (mm)]
a
Additional amount for pipe
length [lbs./ft. (kg/m)]
ø1/4" (6.35) 0.014 (0.021)
ø3/8" (9.52) 0.039 (0.058)
2. Calculation of additional amount for pipe length
Total length
of ø
3/8"
(
9.52mm)
liquid pipe
a :
x 0.039 lbs/ft.
(0.058 kg/m)
ft. (m)
lbs. (kg)
Total
length
of ø
1/4"
(
6.35mm)
liquid pipe
a :
x 0.014 lbs/ft.
(0.021 kg/m)
ft. (m)
lbs. (kg)
+
A=
=
Total
lbs. (kg)
3. Calculation of additional charge refrigerant
A =
lbs. (kg)
Round up A to 2 decimal place.
4. Factory charged amount
b : Outdoor unit
factory charged amount
lbs. (kg)
B=
5. Total refrigerant amount check
C = A + B =
lbs. (kg)
Note : Check the total refrigerant amount under the following conditions.
Condition Computational formula
Total amount of refrigerant ≤ 34.61 lbs. (15.70kg) C ≤ 34.61 lbs. (15.70kg)
When total refrigerant amount exceed limitation.
● Reduce pipe length for refrigerant system.
● Change the refrigerant system configuration.
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