LG LAN091CNP, LAU091CNP, LAN121CNP - Page 61

Service Manual 61
Troubleshooting Guide
Additional gas charging
(Gas leakage)
• When refrigerant is insufficient by leakage, recharge the unit with the refrigerant up to normal operating suc-
tion pressure.
• Use the graph or the equation below to get operating suction pressure according to indoor and outdoor tem-
perature.
Suction pressure was measured at 3-way valve service port after operating the unit for 10 minutes.
The method of using graph
- Find outdoor temperature.
- Find indoor temperature onto the curve of outdoor temperature.
- Read suction pressure at the axis of ordinates.
The method of using equation
-. Calculate suction pressure after putting indoor and outdoor temperature into the equation.
13
(At operating the Unit for 10 minutes)
Suction Pressure
(Kg/cm
2
.g)
Outdoor Temp.
(˚C)
Indoor Temp. (˚C)
12
11
10
9
8
7
6
5
5 10152025303540
50˚C
40˚C
30˚C
20˚C
10˚C
0˚C
P = 3 + 0.0123 x Tout
1.5
+ 0.8 x Tin
0.5
Where, P : Suction Pressure(kg/cm
2
.
g)
Tout : Outdoor Temperature(˚C)
Tin : Indoor Temperature(˚C)
Operating Suction Pressure (For R410A)
(According to Indoor & Outdoor Temperature)