LG A2UQ166FA0, Service Manual, Page: 71 / 238

Service Manual 71
Installation
6. CST Type Indoor Unit
• Drain piping must have down-slope (1/50 to 1/100):
be sure not to provide up-and-down slope to prevent
reversal flow.
• During drain piping connection, be careful not to
exert extra force on the drain port on the indoor
unit.
• The outside diameter of the drain connection on
the indoor unit is 32mm.
• Be sure to install heat insulation on the drain piping.
Piping material: Polyvinyl chloride pipe VP-25
and pipe fittings
Heat insulation material: Polyethylene foam with
thickness more than 8 mm.
The air conditioner uses a drain pump to drain water.
Use the following procedure to test the drain pump operation:
• Connect the main drain pipe to the exterior
and leave it provisionally until the test comes
to an end.
• Feed water to the flexible drain hose and
check the piping for leakage.
• Be sure to check the drain pump for normal
operating and noise when electrical wiring is
finished.
• When the test is completed, connect the flexi-
ble drain hose to the drain port on the indoor
unit.
Drain test
Feed water
Drain Pump
Drain pan
Flexible drain hose
(accessory)
Main
drain pipe
Glue the joint
Drain
port
Drain hose connection
Use the clip (accessory)
Maintenance
drain port
Upward
routing
not allowed
Pipe clamp
Indoor unit
1/50~1/100
MAX 700mm