LG LMNH122LRA0 Service Manual page 45

2. Duct Type Indoor Unit
1. Install declination of the indoor unit is very important for the drain of the duct type air conditioner.
2. Minimum thickness of the insulation for the connecting pipe shall be 5mm.
• The unit must be horizontal or declined to the drain hose connected when finished installation.
CORRECT
CAUTION FOR GRADIENT OF
UNIT AND DRAIN PIPING
• Always lay the drain with downward inclination
(1/50 to 1/100).
Prevent any upward flow or reverse flow in any part.
• 5mm or thicker formed thermal insulator shall
always be provided for the drain pipe.
(Drain pump model only)
CORRECT
• Install the P-Trap (or U-Trap) to prevent
a water leakage caused by the blocking
of intake air filter.
Drainage hole
Front of view
Ceiling
INCORRECT
Lay the drain hose with a downware
inclination so water will drain out.
Unit
Make sure to be closed.
• Upward routing not
allowed
700mm
INCORRECT
Applied U-Trap Dimension
A ≥ 70mm
B ≥ 2C
C ≥ 2 x SP
SP = External Pressure
(mmAq)
Ex) External Pressure
= 10mmAq
A ≥ 70mm
B ≥ 40mm
C ≥ 20mm
Drainage hole
Thermal insulator
(Local supply)
Drainage pipe
(Local supply)
Drainage hole
C
A
Service Manual 45
Installation
B
U-Trap