Daikin VRV II Series - How to Calculate the Additional Refrigerant to be Charged

Si39-303 Appendix
General Information 117
7.6 How to calculate the additional refrigerant to be charged
Additional refrigerant to be charged R (Kg)
R should be rounded off in units of 0.1Kg.
Note: If a negative result is gotten for R from the formula at right, no refrigerant needs to be added.
Note:
The amount of refrigerant to be added to the unit should be written on the included “Added Refrigerant”
plate and attached to the rear side of the front cover. Refer next page.
*Example for refrigerant branch using refnet joint and refnet header for RXYQ34MY1B
R=
+
+++
×0.35
Total length (m)
of liquid piping
size at ø22.2
×0.25
Total length (m)
of liquid piping
size at ø19.1
×0.17
Total length (m)
of liquid piping
size at ø15.9
×0.11
Total length (m)
of liquid piping
size at ø12.7
+-
×
0.054
Total length (m)
of liquid piping
size at ø9.5
× 0.022
Total length (m)
of liquid piping
size at ø6.4
Model name
RXYQ5 ~ 16MY1B
RXYQ18 ~ 32MY1B
RXYQ34 ~ 48MY1B
Amount of refrigerant
0 kg
3 kg
6 kg
H1
H2
a
i
b
Outdoor unit
cde f
g
h
123456
Indoor units (1-8)
Refnet header
k
j
78
H3
REFNET joint (A • B)
AB
If the outdoor unit is
RXYQ34MY1B and the
piping lengths are as at
right
R=
a b j c+d+e+f g+h+j+k
+30×0.25
a: ø19.1 × 30m
b: ø15.9 × 10m
c: ø 9.5 × 10m
d: ø 9.5 × 10m
e: ø 9.5 × 10m
f:ø 9.5 × 10m
g: ø 6.4 × 10m
h: ø 6.4 × 20m
i:ø12.7 × 10m
j:ø6.4 × 10m
k: ø6.4 × 9m
+10×0.17 +10×0.11 +40× 0.054 - 6 = 7.35840× 0.022
7.5
ò