DC Inverter Multi VRF System
20
Diameter of
liquid pipe
(mm/inch)
Φ
22.2
(
Φ
7/8)
Φ
19.05
(
Φ
3/4)
Φ
15.9
(
Φ
5/8)
Φ
12.7
(
Φ
1/2)
Φ
9.52
(
Φ
3/8)
Φ
6.35
(
Φ
1/4)
kg/m
0.35
0.25
0.17
0.11
0.054
0.022
oz/inch
0.314
0.224
0.152
0.099
0.048
0.020
NOTICE!
Liquid pipe that is within 20m (65
feet) doesn’t need added
refrigerant.
First confirm that there is no leakage from the system. When compressor is not working,
charge additional R410a with specific amount to the unit through the filling opening of the liquid
pipe valve of the outdoor unit. If required amount cannot be quickly filled due to pressure increase
of the pipe, set the unit in cooling startup and fill refrigerant from the low pressure check valve of
the outdoor unit.
(3) Calculation example
Fig. 23
IDU
No.
IDU
ķ
IDU
ĸ
IDU
Ĺ
IDU
ĺ
Model
Duct type
BDDL-5.6(18)SAK
Duct type
BDDL-3.6(12)SAK
Duct type
BDDL-2.8(09)SAK
Duct type
BDDL-2.8(09)SAK
Liquid pipe:
No.
A
B
C
D
Pipe size
φ
9.52
mm
(
φ
3/8inch)
φ
9.52mm
(
φ
3/8inch)
φ
9.52mm
(
φ
3/8inch)
φ
6.35mm
(
φ
1/4inch)
Length
10m
(32-3/4feet)
5m
(16-3/8feet)
5m
(16-3/8feet)
5m
(16-3/8feet)
No.
a
b
c
d
Pipe size
φ
9.52mm
(
φ
3/8inch)
φ
6.35mm
(
φ
1/4inch)
φ
6.35mm
(
φ
1/4inch)
φ
6.35mm
(
φ
1/4inch)
Length
3m
(9-3/4feet)
3m
(9-3/4feet)
2m
(6-5/8feet)
1m
(3-1/4feet)
Total length of each liquid pipe
φ
9.52
˖
A+B+C+a=10+5+5+3=23m
3/8Inch: A+B+C+a = 32-1/2 + 16-1/2 + 16-1/2 + 10 = 75-1/2 feet
φ
6.35: D+b+c+d=5+3+2+1=11m
