45
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.
CONDENSATE PIPING
Install the Condensation Drain Pipe
•
Drain piping must slope down or flow may reverse back to unit.
• During drain piping connection, be careful not to exert extra force
on the drain port on the indoor unit.
• Refer to Table 17 for drain pipe sizing.
• Use polyvinyl chloride pipe.
• Install insulation on the drain piping.
• Use polyethylene foam greater than 5/16 inch thick for insulation.
1. Refer to Figure 30 and plan the drain pipe routing so that the pipe
will slope downward from the indoor unit to its end drain location.
2. Connect the provided flexible drain pipe to the main drain pipe.
3. Pour water into the flexible pipe as shown in Figure 33 to test for
leaks. Repair leaks if necessary.
4. Route the flexible drain pipe to the indoor unit and connect the
flexible drain pipe to the drain port of the indoor unit.
5. Install field-supplied thermal insulation on the flexible drain pipe
and position snugly against indoor unit.
Figure 28: Vertical / Horizontal Air Handler Unit Drain Piping System.
Drain for Upflow Installations
Horizontal-Left
Drain Access Hole
Air Filter Cover
Main drain along with suitable trap.
(A field-supplied trap with sufficient depth can be used. Standard-sized traps
are not sufficient. Refer to the U-Trap Specifications figure for the recommended
condensate trap.)
Supplementary drain
with proper trap. (Field-
supplied kit can be used.)
Drain for Horizontal-Left Installations
Figure 29:
Vertical / Horizontal Air Handler Unit U-Trap Specifications.
U-Trap
B
C
A ≥ 2-9/16 inch
B ≥ 2C
C ≥ 2 x SP
SP = External Pressure
(in. WG)
Ex) External Pressure
= 0.4 in. WG
A ≥ 2-9/16 inches
B ≥ 1-7/12 inches
C ≥ 13/16 inches
A
Applied U-Trap Dimensions
• Install the U-Trap to prevent leaks
caused by blocking the intake air filter.
3/4 inch
connector
Vertical/Horizontal Air Handler Unit Drain Information
Note:
Install a field-supplied external condensate pan underneath the entire
vertical air handler unit to avoid damage due to condensate overflow.
Vertical / Horizontal Air Handler units have a gravity drain.
•
Avoid blocking filter access panel when connecting drain lines.
• An additional external condensate line should run from the unit
into the pan.
• The entire condensate line should be drained from the external
condensate pan.
•
Point the drain hose downward for easy drain flow.
•
Do not use pipe joint connection or PVC/CPVC for the unit
drain line connection. Use Teflon® tape.
Maintenance
drain port
Upward
routing
not allowed
Pipe clamp
Indoor unit
Figure 30: Drain Piping Slope.
Insulation
Required
Insulation
Not Required
Properly Fitting Insulation
Figure 31: Properly Insulating the Drainage Piping.
Pour water to
test for proper
drainage and
no leaks
Drain Pump
Drain pan
Flexible drain hose
Main drain pipe
Glue the joint
Drain
port
Drain hose clip (provided)
Flexible drain hose
Figure 32: Do Not Sharply Bend Drain Pipe.
Figure 33: Testing the Drain Pipe.
