LG Multi V ARWN Series Installation Manual page 16

16
! WARNING
Pipe length after header branching (a~f)
It is recommended that difference in length of the pipes con-
nected to the Indoor Units is minimized. Performance difference
between Indoor Units may occur.
Outside 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
20HP(58kW) outside unit .
1) Outside unit main pipe diameter A : Ø28.58(Gas pipe),
Ø12.7(liquid pipe)
2) Pipe diameter B after first branch according to 120% indoor unit
ombination(69.6kW) : Ø28.58(gas pipe), Ø15.88(liquid pipe)
Therefore, pipe diameter B connected after first branch
would be Ø28.58(gas pipe) / Ø12.7(liquid pipe) which is
same with main pipe diameter.
Indoor Unit Connection
Indoor unit connecting pipe from branch (a~f)
Indoor Unit capacity Liquid pipe
[kW(Btu/h)] [mm(inch)]
≤ 5.6(19,100)
Ø6.35(1/4)
< 16.0(54,600) Ø9.52(3/8)
< 22.4(76,400) Ø9.52(3/8)
< 28.0(95,900) Ø9.52(3/8)
! CAUTION
• Bending radius should be
at least twice the diameter
of the pipe.
• Bend pipe after 500 mm or
more from branch(or
header).
Do not bend U type.
It may cause Performance
unsatisfactory or noise.
Pipe Connection Method/Precautions for
Series connections between Outside units
- Separate Y branch joints are needed for series connections between
outside unit s.
- Please refer to the below connection examples to install pipe connec-
tions between outside unit s.
Pipe connection between outside
unit s (General Case)
Pipes between outside unit s
are 2m or less
Gas pipe
[mm(inch)]
Ø12.7(1/2)
Ø15.88(5/8)
Ø19.05(3/4)
Ø22.2(7/8)
500mm or more 500mm or more
The maximum pipe
length after the first
branching between the
outside unit is 10m or les
2m or less
Pipes between outside unit
s are 2m or longer
- If the distance between the outside unit s becomes more than 2m,
apply Oil Traps between the gas pipes.
- If the outside unit is located lower than the main pipe, apply Oil Trap.
Oil trap application method between outside units
- Because of the possibility of oil being accumulated in the outside unit
that has stopped, when there is a height difference between outside
unit pipes or if the pipe distance between the outside units is over
2m, you must always apply an oil trap. (But, the oil trap between out-
side units is limited to 1 time and is only applied to the gas pipe.)
- If the pipe distance between the outside units is 2m or below, and if
the location of the main pipe is lower than that of the outside unit and
if the location of the main pipe is lower than that of the outside unit,
the oil trap does not have to be applied.
- If the location of the main pipe is higher than the location of the out-
side unit, be careful since the oil can be accumulated in the stopped
outside unit.
- If there is high/low difference between the outside unit pipes, oil can
be accumulated to the outside unit on the lower location until the unit
stops.
Examples of Wrong Pipe Connections
If the main pipe is
higher than the
outside unit, oil is
accumulated in the
outside unit.
If there are differences in the height
between the outside unit, oil is
accumulated in the lower outside unit.
- The pipes between the outside unit s must maintain horizontal level-
ness or give an inclination to prevent a back flow toward the slave
outside unit . Otherwise, the unit may not operate properly.
(Example 1)
Toward indoor unit
(Example 2)
Toward indoor unit
Pipe inclination
(2 or more)
(Example 3)
Toward indoor unit
Oil Trap
0.2m or more
2m or less
2m or longer
Oil Trap Oil Trap
2m or less 2m or less
2m or longer 2m or longer
Oil Trap
Toward indoor unit
Toward indoor unit
Toward indoor unit