Condensate Piping - LG Multi V ARNU073M2A4 Installation Manual

General Condensate Piping Information
All ducted indoor units except the vertical air handling unit have a
factory-mounted condensate pump that runs continuously while the
unit is in cooling mode. The pump has an internal high-level float
switch that stops the unit if the water level in the pan rises too high.
All ducted indoor units have a flexible drain hose kit and one or
two clamps. The hose can be used to connect the condensate pipe
to the condensate pump connection. On mid and high-static units,
there is the option to directly connect a 3/4 inch FPT fitting to the
drain pan's gravity drain connection.
Note:
When making condensate pipe connections, be careful not to exert lateral force on the drain nipple. Internal damage may occur. Refer to the
table above for condensate pipe connection sizes.
High Static, Mid Static, Low Static Ducted Condensate Pump
Connections
High Static, Mid Static, Low Static Ducted units have a condensate
pump. Note the following when connecting the condensate pipe to
the unit (See Figure at right).
• Indoor units DO NOT come with check valves or a backflow preven-
tion device. If check valves are needed, they must be field supplied.
• The maximum lift of all condensate pumps is 27 in.-wg.
• Measure lift distance from the bottom surface of the indoor unit,
NOT from the condensate pipe connection.
• Slope all horizontal condensate pipe segments a minimum of 1/4
inch per foot away from the indoor unit.
High Static, Mid Static, Low Static Ducted Unit Drain Information
When the bottom surface of the indoor unit is at an elevation below
the receiving building drain line connection, install an inverted trap at
the top of the condensate pump discharge riser before connection to
the building drain pipe.
When the receiving drain line is mounted horizontal, connect the
inverted trap to the top half of the pipe. The connection point of the
inverted trap to the building drain pipe should always be to the top
half of the pipe and should never be over 45° either side of the up-
per most point of the horizontal building drain line.
If connecting to a vertical drain line or plumbing system vent line,
connect the IDU condensate pump discharge line using a Y-45 fitting
with the double end of the Y-45 fitting facing up. When connecting
to a vertical drain line include an inverted trap at the top of the IDU
condensate pump discharge riser before connection to the Y-45
fitting.
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

Table 23: Indoor Unit Drainage Specifications.
Indoor Unit
B8, MA, M1, M2, M3 Frame
Mid Static Ducted and High
Static Ducted
L1, L2, L3 Frame
Low Static Ducted
NJ, NK Frame Vertical/Horizontal
Air Handler Unit
Figure 41: High Static, Mid Static, Low Static Ducted Indoor Unit Drain
Pump to Drain Piping System
Metal
clamp
Drain pump
Figure 42: Gravity Condensate Trap..
• Install the U-Trap to prevent leaks
caused by blocking the intake air filter.
Applied U-Trap Dimensions
A ≥ 2-3/4 inch
B ≥ 2C
C ≥ 2 x SP
SP = External Pressure
(in. WG)
Ex) External Pressure
= 0.39 in. WG
A ≥ 2-3/4 inches
B ≥ 1-9/16 inches
C ≥ 25/32 inches
Drain Pipe Dia.
Drain Type
(ID, in.)
27 in. Lift
Drain Pump, Ø1
Factory Installed
Gravity Ø1
Hanger distance
Max.
3.3~4.9 feet
Hanger Bracket
11-13/16 inches
1/50~1/100
slope
PVC Elbow
Max.
27 in. lift
PVC Piping
Flexible drain hose
Insulation
C
U-Trap
A
B
51