
3.8.2 Refrigerant charge
The calculation of the additional charge should be taken into account for the additional length of pipe.
n
(1Ø)
Additional charge (g)
= ((A Room Installation Length – Standard Length (A) ) x a
+ (B Room Installation Length – Standard Length (A) ) x a +.. )
- CF(Correction Factor) x 150
h
CF = Max. number of connectable indoor unit – Total number of connected indoor unit
Model
Standard length, A (m)
Additional refrigerant, a (g/m)
A2UW16GFA0
7.5
20
A3UW21GFA0
7.5
20
A5UW30GFA0
7.5
20
A5UW40GFA0
7.5
20
Heat pump
60Hz/R410A
_
52
3. Installation of outdoor unit
Part 3 Design and installation
• Each branch pipe
a = 5m
b = 10m
c = 15m
d = 25m
❖
Additional Charge
= (5-7.5) x 20
+ (10-7.5) x 20
+ (15-7.5) x 20
+ (25-7.5) x 20
– (5-4) x 150
= 0+50+150+350-150 = 400g
a
b
c
d
7k
7k
9k
12k
Ex) A5UW30GFA0[MU5M30 U42]
Additional refrigerant charge calculation example - 1