Refrigerant Piping System - LG MULTI V Series Installation Manual

Refrigerant piping system

Y branch method
Example : 5 Indoor Units
connected
Ⓐ : Outdoor Unit
Ⓑ : 1st branch (Y branch)
Ⓒ : Indoor Units
Total pipe length = A+B+C+D+a+b+c+d+e ≤ 150 m
Longest pipe length
L
A+B+C+D+e ≤ 80 m
Longest pipe length after 1st branch
B+C+D+e ≤ 40 m
Difference in height (Outdoor Unit ÷ Indoor Unit)
H
H ≤ 30 m (20 m : Outdoor Unit is lower than Indoor Units)
Difference in height (Indoor Unit ÷ Indoor Unit)
h
h ≤ 15 m
• * : Assume equivalent pipe length of Y branch to be 0.5 m, that
of header to be 1 m, calculation purpose.
Refrigerant pipe diameter from outdoor unit to first branch. (A)
Outdoor unit
Liquid pipe [mm(inch)]
total capacity (HP)
6 Ø 9.52(3/8)
5 Ø 9.52(3/8)
4 / 3 Ø 9.52(3/8)
Refrigerant pipe diameter from branch to branch (B,C,D)
Downward Indoor
Unit total capacity Liquid pipe [mm(inch)]
[kW(Btu/h)]
≤ 5.6(19 100)
Ø 6.35(1/4)
< 16.0(54 600) Ø 9.52(3/8)
≤ 22.4(76 400)
Ø 9.52(3/8)
WARNING
!
When the any one (or both ) of below conditions are satisfied, the
diameter of main pipe (A) must be increased according to below
table.
- The equivalent length between outdoor unit and the farthest
indoor unit is 90 m or more.
(Liquid and Gas pipes are increased.)
L80 m
l 40 m
Equivalent pipe length(*)
A+B+C+D+e ≤ 100 m
Gas pipe [mm(inch)]
Ø 19.05(3/4)
Ø 15.88(5/8)
Ø 15.88(5/8)
Gas pipe [mm(inch)]
Ø 12.7(1/2)
Ø 15.88(5/8)
Ø 19.05(3/4)
Header Method
Example : 6 Indoor Units
connected
Ⓐ : Outdoor Unit
Ⓑ : 1st branch
Ⓒ : Indoor Units
Ⓓ : Sealed piping
Total pipe length = A+a+b+c+d+e+f ≤ 150 m
Longest pipe length
L
A+f ≤ 80 m
Longest pipe length after 1st branch
f ≤ 40 m
Difference in height (Outdoor Unit ÷ Indoor Unit)
H
H ≤ 30 m (20 m : Outdoor Unit is lower than Indoor Units)
Difference in height (Indoor Unit ÷ Indoor Unit)
h
h ≤ 15 m
WARNING
!
Pipe length after header branching (a~f)
It is recommended that difference in length of the pipes
connected to the Indoor Units is minimized. Performance
difference between Indoor Units may occur.
• * : Assume equivalent piping length of Y branch to be 0.5 m,
that of header to be 1 m, calculation purpose.
• Indoor Unit should be installed at lower position than the header.
Combination of Y
branch/header Method
Example : 5 Indoor Units
connected
Ⓐ : Outdoor Unit
Ⓑ : 1st branch (Y branch)
Ⓒ : Y branch
Ⓓ : Indoor Unit
Ⓔ : Header
Ⓕ : Sealed piping
Branch pipe can not be used after header.
Total pipe length = A+B+C+a+b+c+d+e ≤ 150 m
Longest pipe length
L
A+B+b ≤ 80 m
Longest pipe length after 1st branch
B+b ≤ 40 m
Difference in height (Outdoor Unit ÷ Indoor Unit)
H
H ≤ 30 m (20 m : Outdoor Unit is lower than Indoor Units)
Difference in height (Indoor Unit ÷ Indoor Unit)
h
h ≤ 15 m
• * : Assume equivalent pipe length of Y branch to be 0.5 m,
that of header to be 1 m, calculation purpose.
• Indoor Unit should be installed at lower position than the
header.
17
L 80 m
40 m
Equivalent pipe length(*)
A+f ≤ 100 m
L 80 m
40 m
Equivalent pipe length(*)
A+B+b ≤ 100 m