LG Multi V IV PRHR041 Installation Manual page 17

Pattern 7
A
HR1
1 2
48k 48k
• * : Serial connection of HR units : Capacity sum of indoor units ≤ 192 kBtu/h
Pattern 8
A
HR1
1 2
48k 48k
• * : Maximum indoor units per a branch are 8 indoor units
Indoor Unit Y Branch pipe
1
Low pressure Gas pipe
Outdoor
High pressure Gas pipe
Unit
Liquid pipe
• Pipe installation from outdoor units to HR units
: 3 pipes(Low pressure Gas pipe, High pressure Gas pipe, Liquid pipe)
• Pipe installation from HR units to indoor units
: 2 pipes(Gas pipe, Liquid pipe)
Keep the 40m distance from the first branch to the farthest indoor.
1) under 40m
Indoor Indoor
Y branch
Unit Unit
Keep the sum of indoor capacity under 56.4kW(192 kBtu/h).
1) under 40m
Indoor Indoor Indoor Indoor
Unit Unit Unit Unit
Keep the sum of indoor capacity under 56.4kW(192 kBtu/h).
HR2 HR3
3 4 5 6
48k 48k 48k 48k
HR2
A
B
3 4 5 6 7
12k 12k 12k 12k 24k
Head Branch pipe
B
A
Gas pipe
Indoor
HR1
Unit
Liquid pipe
Indoor Indoor
Unit Unit
Indoor Indoor Indoor Indoor
Unit Unit Unit Unit
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(Low pressure
gas pipe), Ø15.88(liquid pipe), Ø28.58(High Pressure liq-
uid pipe)
2) Pipe diameter B after first branch according to 120% in-
door unit combination(84kW) : Ø34.9(Low pressure gas
pipe), Ø19.05(liquid pipe), Ø28.58(High Pressure liquid
pipe)
Therefore, pipe diameter B connected after first branch
would be Ø34.9(Low pressure gas pipe), Ø15.88(liquid
*
pipe), Ø28.58(High Pressure liquid pipe) which is same
with main pipe diameter.
[Example]
Do not choose the main pipe diameter by downward indoor unit
total capacity but its outdoor unit model name.
Do not let the connection pipe from branch to branch exceed the
main pipe diameter chosen by outdoor unit model name.
8
EX) Where connecting the indoor units to the 22 HP (61.5 kW)
24k
outdoor unit to 120% of its system capacity (73.8 kW) and
branching 7k (2.1kW) indoor unit at the 1st branch
Main pipe diameter(22 HP outdoor unit): Ø28.58(Low pressure
gas pipe), Ø15.88(Liquid pipe), Ø22.2(High pressure gas pipe)
Pipe diameter between 1st and 2nd branch (71.7kW indoor units):
Ø34.9(Gas pipe) Ø19.05(Liquid pipe) in conformity with down-
ward indoor units.
Since the main pipe diameter of 22HP outdoor unit is
Ø28.58(Low pressure gas pipe), Ø15.88(Liquid pipe), Ø22.2(High
pressure gas pipe) is used as the main pipe and the connection
pipe between 1st and 2nd branch.
Indoor Unit Connection
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)
< 28.0(95,900)
CAUTION
!
• Bending radius should be
at least twice the diameter
of the pipe.
• Bend pipe after 500mm or
more from branch(or
header).
Do not bend U type.
It may cause Performance
unsatisfactory or noise.
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)
Ø9.52(3/8) Ø22.2(7/8)
500mm or more 500mm or more
17