Refrigerant Piping Insulation - LG MULTI F Installation Manual

F
MULTI
F
MULTI MAX
Tightening the Flare Nuts
Tightening Torque for Flare Nuts.
Pipe Size (in. O.D.) Outside Diameter (mm)
1/4
3/8
1/2
5/8
3/4
1. When connecting the flare nuts, coat the flare (outside only) with polyvinyl ether (PVE) refrigeration oil only.
Do not use polyolyester (POE) or any other type of mineral oil as a thread lubricant. These lubricants are not compatible with the PVE oil
used in this system and create oil sludge leading to equipment damage and system malfunction.
Do not add any contaminants inside the refrigerant piping.
2. Initially hand tighten the flare nuts using three (3) or four (4) turns.
3. To finish tightening the flare nuts, use both a torque wrench and a backup wrench.
4. After all the piping has been connected and the caps have been tightened, check for refrigerant gas leaks.
Loosening the Flare Nuts
Always use two (2) wrenches to loosen the flare nuts.
Brazing Procedure
WARNING
Do not braze in an enclosed location.
If the refrigerant combusts, it generates a toxic gas the will cause physical injury or death.
Braze the pipes to the service valve pipe stub of the outdoor unit.
1. All joints are brazed in the field. LG HVAC refrigeration system components contain
very small capillary tubes, small orifices, electronic expansion valves, oil separators,
and heat exchangers that can easily become blocked. Proper system operation de-
pends on the installer using best practices and utmost care while assembling the piping
system.
2. Store pipe stock in a dry place; keep stored pipe capped and clean.
3. Blow clean all pipe sections with dry nitrogen prior to assembly.
4. Use adapters to assemble different sizes of pipe.
5. Always use a non-oxidizing material for brazing.
oxidized film will accumulate and clog or damage the compressors. Flux can harm the copper piping or refrigerant oil.
6. Use a tubing cutter, do not use a saw to cut pipe. De-bur and clean all cuts before assembly.
7. Brazing joints:
• Use a dry nitrogen purge operating at a minimum pressure of three (3) psig and maintain a steady flow.
• Use a 15% silver phosphorous copper brazing alloy to avoid overheating and produce good flow.
• Protect isolation valves, electronic expansion valves, and other heat-sensitive control components from excessive heat with a wet rag or
heat barrier spray.
FLARING AND BRAZING PROCEDURES
Tightening Torque (ft-lbs.)
13.0 - 18.0
6.35
9.52 24.6 - 30.4
39.8 - 47.7
12.7
15.88 45.4 - 59.3
71.5 - 87.5
19.05
Do not allow the refrigerant to leak during brazing. Always test for gas leaks before and after brazing.
Do not use flux, soft solder, or anti-oxidant agents. If the proper material is not used,
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.
Figure 42: Refrigerant Pipe Brazing.
Refrigerant
Piping
Pipe to
be brazed
Nitrogen
Taping
Pressure-reducing
Valve
Valve
47