LG MULTI V WATER IV ARWN120LAS4, Installation Manual, Page: 36 / 79

36 Outside Unit 36 Outside Unit
Refrigerant piping system
Required Example
1
Select the diameter of the pipe be-
tween the 1st branch and the last
branch to be 1 level larger.
Provided that, it is not necessary if
the pipe diameter is the same as the
main pipe.
40 m < B+C+D+e ≤ 90 m
→
Change B, C, and D pipe
diameter.
Ø6.35 Ø9.52, Ø9.52 Ø12.7,
Ø12.7 Ø15.88, Ø15.88 Ø19.05,
Ø19.05 Ø22.2, Ø22.2 Ø25.4,
Ø25.4 Ø28.58, Ø28.58 Ø31.8,
Ø31.8 Ø34.9, Ø34.9 Ø38.1
2
During the calculation of the total re-
frigerant pipe length, the above pipe
length shall be calculated as twice.
A+Bx2+Cx2+
Dx2+a+b+c+d+e ≤ 500 m
L
H 50 m
40 m
IDU
Direction
3
The length from each indoor unit to
the nearest branch pipe ≤ 40 m
a,b,c,d,e ≤ 40 m
4
Length from outdoor unit to the far-
thest indoor unit] – [Length from out-
door unit to the nearest indoor unit] ≤
40 m
(A+B+C+D+e)-(A+a)
≤ 40 m
WARNING
To install maximum pipe length after the 1st branch exceeding 40 m and 90 m or less, the following condi-
tions must be satisfied.
WARNING
• It is recommended to install the difference between the length of the pipe after header branch(a~f) and the
length of the pipe connected to indoor unit to be the minimum.
• As the pipe length difference increases, there may be performance differences between indoor units.
• Y branch and header branch cannot be used after header branch.
WARNING
If the pipe diameter(B, C) connected after the 1st branch is larger than the main pipe diameter(A), install the
pipe diameter(B, C) connected after the 1st branch to be the same as the main pipe diameter(A).
Example) If indoor units are connected 120 % to 29 kW
• Outdoor unit main pipe diameter(A): (Gas pipe) (Fluid pipe)
• Pipe diameter(B, C) after the 1st branch according to 120% indoor unit combination(34.8kW):
(Gas pipe) (Fluid pipe)
Therefore, select the pipe diameter(B, C) after the 1st branch to be main pipe diameter(A) (Gas pipe) (Fluid pipe)
◆
Cautions for Y branch pipe
◆
Cautions for header branch pipe
◆
(Table 1) Cautions during the installation of Maximum pipe length 90m after the 1st branch