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MUL
TI V S System Installation Manual
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.
Pipe Slope
The horizontal pipe slope cannot exceed 5° up or down.
In-line Refrigeration Components
Components such as oil traps, solenoid valves, filter-dryers, sight glasses, tee fittings, and other after-market accessories are not permitted
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assure oil is properly returned to the compressor. Sight-glasses and solenoid valves may cause vapor to form in the liquid stream. Over time,
dryers may deteriorate and introduce debris into the system. The designer and installer should verify the refrigerant piping system is free of
traps, sagging pipes, sight glasses, filter dryers, etc.
GENERAL INSTALLATION GUIDELINES
Piping Preparation
Field-Provided Isolation Ball Valves
LG maintains a neutral position on using isolation valves in VRF refrigerant piping systems. LG does not endorse any manufacturer of isola-
tion valves. It is recognized that installing isolation valves may simplify future maintenance requirements, and, if used, considerations should
be taken including, but not limited to, the following:
• Pressure drops for any component used, including isolation valves, must be known in equivalent pipe length and calculated into the total
and segment equivalent piping lengths and compared to product design limitations.
• In all cases, materials must be suitable for the application and any applicable codes, including, but not limited to, diameter and wall
thickness continuity per ACR standards.
Failure to do so may cause significant performance degradation. Proper leak checks must be performed. Using isolation valves does not
automatically void any LG product warranty; however, a limited warranty may be voided in whole or part should any field supplied accessory
fail in any way that causes product failure.
In-line Refrigeration Components
Components such as oil traps, solenoid valves, filter-dryers, sight glasses, tee fittings, and other after-market accessories are not permitted
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with redundant systems that assure oil is properly returned to the compressor. Sight-glasses and solenoid valves may cause vapor to form
in the liquid stream. Over time, dryers may deteriorate and introduce debris into the system. The designer and installer should verify the
refrigerant piping system is free of traps, sagging pipes, sight glasses, filter dryers, etc.
No Pipe Size Substitutions
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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 long radius and designed for use with R410A refrigerant. The designer, however, should
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-
tion for each branch. The equivalent pipe length of each elbow must be added to each pipe segment in the LATS program.
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problems or damages as a result of interconnecting piping, their joint connections, isolation valves, introduced debris inside the piping system, or
other problems caused by the interconnecting piping system.
Pipe Bends
When bending soft copper, use long radius bends. Refer to the “Radii of Coiled Expansion Loops and Developed Lengths of Expansion
Offsets” table for minimum radius specifications, page 23.
