LG MULTI V Installation Manual page 39

u Outdoor unit Connection
WARNING
• In case of pipe diameter B connected after first branch is bigger than the main pipe diameter A, B should be of the same
size with A.
Ex) In case indoor unit combination ratio 120% is connected to 70kW outdoor unit.
1) Outdoor unit main pipe diameter A : Ø34.9(1-3/8, gas pipe), Ø15.88(5/8, liquid pipe)
2) Pipe diameter B after first branch according to 120% indoor unit combination(84kW) : Ø34.9(1-3/8, gas pipe),
Ø19.05(3/4, liquid pipe)
Therefore, pipe diameter B connected after first branch would be Ø34.9(1-3/8, gas pipe) / Ø15.88(5/8, liquid pipe)
which is same with main pipe diameter.
[Example]
Instead of using indoor unit total capacity, use outdoor unit model name in order to choose main pipe diameter by
downward.
Do not let the connection pipe from branch to branch exceed the main pipe diameter chosen by outdoor unit model name.
EX) Where connecting the indoor units to the 22 HP (61.6kW) outdoor unit to 120% of its system capacity (73.8 kW) and
branching 7k Btu/h(2.2kW) indoor unit at the 1st branch
Main pipe diameter(22 HP outdoor unit): Ø28.58(1-1/8, Gas pipe) Ø15.88(5/8, Liquid pipe)
Pipe diameter between 1st and 2nd branch (71.7kW indoor units):
Ø34.9(1-3/8, Gas pipe) Ø19.05(3/4, Liquid pipe) in conformity with downward indoor units.
Since the main pipe diameter of 22HP outdoor unit is Ø28.58(1-1/8, Gas pipe) and Ø15.88(5/8, Liquid pipe), Ø28.58 (1-
1/8, Gas pipe) and Ø15.88(5/8, Liquid pipe) is used as the main pipe and the connection pipe between 1st and 2nd
branch.
* High/Low Pressure Common Pipe: Ø19.05(3/4) ; 14HP or more
u Indoor Unit Connection
Ú Indoor Unit connecting pipe from branch (a,b,c,d,e,f)
Indoor Unit capacity [kW(Btu/h)]
≤ 5.6(19,100)
< 16.0(54,600)
≤ 22.4(76,400)
* ARNU093TN*2, ARNU123TN*2, ARNU153TN*2, ARNU183TM*2, ARNU243TM*2 : Liquid pipe Ø9.52(3/8), Gas pipe
Ø15.88(5/8)
ARNU153BG*2, ARNU183BG*2, ARNU243BG*2 : Liquid pipe Ø9.52(3/8), Gas pipe Ø15.88(5/8)
Pipe connections between indoor and outdoor unit
Liquid pipe Gas pipe
[mm(inch)] [mm(inch)]
Ø6.35(1/4) Ø12.7(1/2)
Ø9.52(3/8) Ø15.88(5/8)
Ø9.52(3/8) Ø19.05(3/4)
Installation Manual 39