Technical Data Manual

Design of Mini VRF SYSTEM
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2. System Design
Material O
Copper tube
Outer diameter 1/4 (6.35) 3/8 (9.52) 1/2 (12.7) 5/8 (15.88) 3/4 (19.05)
Wall thickness 1/32 (0.8) 1/32 (0.8) 1/32 (0.8) 5/128 (1.0)
over 5/128 (1.0)
Table 2-7 Required Copper Tubing Dimensions
Unit: in. (mm)
Gas tubing size (in. (mm))
90°
elbow
45°
elbow
Trap bend
1/2" (12.7)
1
0.8
3
7.5
5/8" (15.88)
1.1
0.9
3.4
9.2
3/4" (19.05)
1.4
1
4.1
10.5
Y-branch distribution joint
Ball valve for ser
vice
U-shape tube bend (R2-3/8" – 4" (60 – 100))
Equivalent length conversion not needed.
Equivalent length conversion not needed.
2-6. Straight Equivalent Length of Joints
Design the tubing system by referring to the following table for the straight equivalent length of joints.
Table 2-6 Straight Equivalent Length of Joints
Unit: ft.
Table 2-5 Indoor Unit Tubing Connection (
1
,
2
...
n–1
)
ø5/8" (ø15.88)
ø3/8" (ø9.52)
ø1/2" (ø12.7)
ø1/4" (ø6.35)
7 9 12 18 3624 48Indoor unit type
Gas tubing
Liquid tubing
Unit: in. (mm)
5415 19
24,200
(
2.5 h
p)
ø
5/
8
"
(
ø
1
5.
88
)
ø
1/2"
(
ø
12.7
)
ø
3
/4"
(
ø
19.05
)
ø
3
/
8
"
(
ø
9.52
)
ø
3
/
8
"
(
ø
9.52
)
24,200
(
2.5 h
p)
–
38
,200
(
4 h
p)
4
7
,
8
00
(
5 h
p)
52,900
(
6 h
p)
B
e
l
o
w BT
U/h
Ov
er BT
U/h
Tubing size
Total capacity
after distribution
s
t
u
bi
n
g
Liqui
d
t
u
bi
n
g
h
p
= ho
r
sepower
U
n
it: in. (mm)
2-5. Tubing Size
Table 2-3 Main Tubing Size (LA)
ø 3/4" (ø19.05)
6
Unit: in. (mm)
52,900 (15.5)
ø 3/8" (ø9.52)
ø5/8" (ø15.88)
4
38,200 (11.2)
BTU/h (kW)
System horsepower
Gas tubing
Liquid tubing
Note: If the system consists of only one indoor unit with an outdoor 6HP (Type 52), the main tube of the unit (LA) should be
ø19.05. Convert ø19.05 to ø15.88 using a reducer (field supply) close to the indoor unit and then make the connection.
Table 2-4 Main Tubing Size After Distribution (LB, LC...)
Note: In case the total capacity of connected indoor units exceeds the total capacity of the outdoor units, select the main
tubing size for the total capacity of the outdoor units.
TD831156-00_MINI_VRF_SYS.indb 14TD831156-00_MINI_VRF_SYS.indb 14 2012/01/31 14:38:442012/01/31 14:38:44