LG ARWN Series, Installation Manual

Page: 32 / 75

Refrigerant piping system
Y/Header branch method
* For the first branch pipe (B), use the branch pipe
that fits the main pipe diameter (A)
Outside unit capacity Liquid pipe (mm) Gas pipe (mm)
8HP Ø9.52 Ø22.2
16 HP Ø12.7 Ø28.58
Ú
Refrigerant pipe diameter from
branch to branch (B, C)
Ú
Total pipe length
=A +B +C +a +b +c +d +e ≤ 300 m
Ú
Outside unit
Ⓐ
~ 1st Y branch
part
Ⓑ
: Main pipe diameter (A)
L Below 150 m
Belo
w H 50 m
Below 40 m
h Belo
w 15 m
• When the pipe diameter (B) connected after 1st branching is larger than the main pipe diameter (A), Install the pipe
with the pipe diameter (B) after 1st branching that is the same as the main pipe diameter (A). Ex) When connecting
with 150% of the indoor unit to 8 HP.
1) Outside unit main pipe diameter: 22.2 (Gas pipe) / 9.52 (Liquid pipe)
2) Pipe diameter after 1st branching by 150% indoor unit combination : 28.58 (Gas pipe) / 12.7 (Liquid pipe)
Therefore set the pipe diameter (B) after 1st branching to 22.2 (Gas pipe) / 9.52 (Liquid pipe) of main pipe diameter (A).
• For the pipe length after the header branch (c~e), it is recommended to install the unit so that the difference of the pipe
distance connected to the indoor unit is minimized.
• The large difference in pipe distance can cause performance difference between indoor units.
• After the header branch, you cannot use the Y branch and header branch.
• When the pipe distance corresponding to the farthest indoor unit from the outside unit is 90m or above, you must
change the main pipe diameter according to the outside unit capacity in accordance with the following table. (This
applies to both the liquid and gas pipes.)
Total capacity of indoor units con-
nected to after branching (kW)
≤ 5.6 Ø6.35 Ø12.7
< 16 Ø9.52 Ø15.88
< 22.4 Ø9.52 Ø19.05
< 33 Ø9.52 Ø22.2
< 47 Ø12.7 Ø28.58
< 71 Ø15.88 Ø28.58
< 104 Ø19.05 Ø34.9
104 ≤ Ø19.05 Ø41.3
Liquid pipe
(mm)
Gas pipe
(mm)
1. When installing 1 outside unit indepen-
dently
Ex) 5 indoor units connected
Ⓐ
: Outside unit
Ⓑ
: 1st Y branch
Ⓒ
: 2nd Y branch
Ⓓ
: Indoor unit
Ⓔ
: Header branch
Ⓕ
: Seal
Longest pipe length (Equivalent pipe length)
A +B +b,A +C +e ≤ 150 m(175 m)
Longest pipe length after 1st branching
B +b,C +e ≤ 40 m
High/Low difference (Outside unit
÷
Indoor unit)
H ≤ 50 m
High/Low difference (Indoor unit
÷
Indoor unit)
h ≤ 15 m
L
ℓ
H
h
Gas Pipe Liquid Pipe
8 HP .............................................Ø22.2
’
Ø25.4 8 HP .............................................Ø9.52
’
Ø12.7
16 HP ...........................................Ø28.58
’
Ø31.8 16 HP ...........................................Ø12.7
’
Ø15.88
32 Outside Unit