LG Air Conditioner Installation Manual page 22

Flaring Work and Connection of Piping
Piping Connection
1. Form the piping according to its routing.
Avoid bending and bending back the same
piping point more than three times. (This will
result in hardening the pipe.)
2. After deforming the piping, align centers of
the union fitting of the indoor unit and the
piping, and tighten them firmly with
wrenches.
3. Connect pipe to the service valve or ball
valve which is located below the outdoor unit.
4. After completing the piping connection, be
sure to check if there is gas leakage in indoor
and outdoor connection.
Vacuum drying
After completing the piping connection,
execute vacuum drying for the connecting
piping and the indoor unit.
The vacuum drying must be carried out
using the service ports of both the liquid and
gas side valves.
CAUTION: Use two wrenches and
tighten with regular torque.'
Outside diameter
mm
Ø6.35
Ø9.52
Ø12.7
Ø15.88
Ø19.05
22 Air Conditioner
torque
kgf . m(lbf . ft)
inch
1.8~2.5 (13~18)
1/4
3.4~4.2 (24~30)
3/8
5.5~6.6 (40~48)
1/2
5/8 6.3~8.2 (46~59)
3/4 9.9~12.1 (72~88)
Liquid side
Outdoor
unit
Gas side
Flare connection
Indoor
unit
Flare connection
Union