LG LC187HV, Engineering Manual, Page: 57 / 76

Figure 37: Installing Piping Above and Below an Obstacle.
Above an obstacle.
3X
Minimum
Below an obstacle.
obstacles
When an obstacle, such as an I-beam or concrete T, is in the path
of the planned refrigerant pipe run, it is best practice to route the
pipe over the obstacle. If adequate space is not available to route
the insulated pipe over the obstacle, then route the pipe under the
obstacle. In either case, it is imperative the horizontal section of pipe
above or below the obstacle be a minimum of three (3) times greater
than the longest vertical rise (or fall) distance.
refrigerant Piping System Layout
reFrigerant PiPing DeSign
Pipe Slope
The horizontal pipe slope cannot exceed 10° up or down.
in-line refrigeration Components
The designer and installer should verify the refrigerant piping system is free of traps, sagging pipes, sight glasses, filter dryers, solonoid
valves, tee fittings, etc., on the refrigerant piping system between the outdoor units and the indoor units. The components may cause vapor
to form in the liquid stream. Over time, dryers may deteriorate and introduce debris into the system.
no Pipe Size Substitutions
Use only the pipe size as conveyed in the product installation instructions. Using a different size is prohibited and may result in a system
malfunction or failure to work at all.
using elbows
Field-supplied elbows are allowed as long as they are designed for
use with R410A refrigerant. The designer, however, should be cau-
tious with the quantity and size of fit-tings used, and must account
for the additional pressure losses in equivalent pipe length calcu-
lation. The equivalent pipe length of each elbow must be added to
each pipe segment.
Table 39: Equivalent Piping Length for Piping Components.
Component Size (Inches)
Elbow (ft.)
1/4 3/8 1/2 5/8 3/4
0.5 0.6 0.7 0.8 1.2
Due to our policy of continuous product innovation, some specifications may change without notification.
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Refrigerant Piping Design and Best Practices