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General Refrigerant Piping System Information
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.
Flaring Procedure
Flaring and Brazing Procedures
One of the main causes of refrigerant leaks is a defective connection. For LG HVAC systems, the installer needs to know how perform both
flared and brazed connections successfully.
When selecting flare fittings, always use a 45° fitting rated for use with high pressure refrigerant R410A. Selected fittings must also comply with local,
state, or federal standards.
• During installation, it is imperative to keep the piping system free of contaminants and debris such as copper burrs, slag, or carbon dust.
•
Do not use kinked pipe caused by excessive bending in one specific area on its length.
3. Flaring the pipe end.
• Use the proper size flaring tool to finish flared connections as
shown.
• ALWAYS create a 45° flare when working with R410A.
1. Cut the pipe to length.
• Measure the distance between the indoor unit and the outdoor unit.
• Cut the pipes a little longer than measured distance.
2A. Remove the burrs.
• Completely remove all burrs from pipe ends.
• When removing burrs, point the end of the copper pipe down to
avoid introducing foreign materials in the pipe.
2B. Slide the flare nut onto the copper tube.
90°
Slanted Uneven Rough
Pipe
Reamer
Point
down
Flare nut
Copper
tube
Bar
Copper pipe
Clamp handle
Red arrow
Cone
Bar
Slanted
Smooth
Uneven
Thickness
1.
2A.
2B.
3.
4.
4. Carefully inspect the flared pipe end.
• Compare the geometry with the figure to the right
• If the flare is defective, cut it off and re-do procedure.
• If flare looks good, blow the pipe clean with dry nitrogen.
90°
45°
“A”
R=0.4
– 0.8
Dimensions of the Flare.
Pipe Size (in. O.D.)
“A” Dimension (mm [in.])
1/2
1/4
5/8
3/8
3/4
Flared Connection Dimensions / Tightening Torque.
Handle
Incorrect Flare
Even Length
Cracked
Yoke
Inside is shiny with no scratches
Surface
Damaged
Copper
tube
Outside Diameter (mm)
6.35
9.52
12.7
15.88
19.05
~
9.1 (11/32 - 23/64)
~
13.2 (1/2 - 33/64)
~
16.6 (41/64 - 21/32)
~
19.7 (49/64 - 25/32)
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FLARING AND BRAZING PROCEDURES
