Refrigerant Pipe Length Limits
Proper system operation depends on the installer using utmost care while assembling the piping system. The following pages are an over-
view of best practices when installing the refrigerant piping system.
One of the most critical elements of a Multi V system is the refrigerant piping. The table below lists pipe length limits that must be followed in
the design of a Multi V refrigerant pipe system:
Table 9: Multi V Refrigerant Piping System Limitations.
Longest total equivalent piping length
Longest distance from outdoor unit to RTU
Distance between fittings and RTU
Pipe Length
Distance between fittings and Y-branches
(ELF = Equivalent Length
Distance between two Y-branches
of pipe in Feet)
Minimum distance between RTU to any Y-branch
Maximum distance between first Y-branch to farthest RTU
Elevation
If outdoor unit is above or below RTU
(All Elevation Limitations
are Measured in Actual
Between RTUs
Feet)
Table 10: Equivalent Piping Length for Y-branches, Headers, and Other Piping Components.
Component
Long Radius Elbow (ft.)
Y-branch (ft.)
1
Kit contains two Y-branches: one for liquid and one for vapor.
1
Selection of Pipe Sizes
For piping work, follow the maximum tolerated length, difference in height, and length after a branch. Determine the proper size referring to
following tables and reference figure (only for indication)
Table 11: Piping Outer Diameter (O.D.) size.
ODU Capacity
Liquid pipe (O.D.) Low Pressure pipe (O.D.)
Ton (kBtu/h)
6 (72)
3/8 in
8 (96)
10 (119.7)
1/2 in
12 (144)
14 (168)
5/8 in
16-18 (192-206)
20 (233.1)
22-28 (264-336)
3/8 in
30-42 (360-504)
1/4
3/8
1/2
5/8
3/4
0.5
0.6
0.7
0.8
1.2
3/4 in
7/8 in
1-1/8 in
1-3/8 in
1-3/8 in
Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. "LG" is a registered trademark of LG Corp.
REFRIGERANT PIPING
131 feet (295 feet for conditional applications)
Size (Inches)
7/8
1
1-1/8 1-1/4 1-3/8 1-1/2 1-5/8
1.3
1.5
1.6
1.8
2.0
High Pressure pipe (O.D.)
5/8 in
3/4 in
7/8 in
1-1/8 in
3,280 feet
656 feet (Actual) 738 feet (Equivalent)
≥20 inches
≥20 inches
≥20 inches
3 feet from RTU to Y-branch
164 feet
98 feet
1-3/4
2-1/8
2.1
2.3
2.5
2.8
35