Function Of Outdoor Unit - LG AMNH096VEA0 Service Manual

Operation

Function of Outdoor Unit

Outdoor Unit
Two Comp algorithm
• Inverter Comp is first priority and then Constant Comp is turning on responding to load condtion.
Operating Frequency
• Inverter Frequency varies considering condition such as room temp,outdoor temp, operating room
number,Temp gap between room temp and set temp and so on.
LEV Control
• LEV pulse is modulated to keep constant superheat or subcooling.
Out door Fan Control
• Outdoor fan operates at High/Low or Off to respond to the load condition.
R/Valve Control
• Convert R/Valve to change cooling to heating, heating to cooling.
Comp Pre-Heat Logic
• Checking outdoor temp, D-Pipe temp,Heat Sink Temp, operate compressor at low frequency upto
5min to preheat oil.
Defrost Function
• After 35 min heating operation, check the defrost condition and if outdoor pipe temp is below -6°C and
released from deice operation in case outdoor pipe temp is over 15°C or 7 min cooing mode.
• To deice outdoor heat exchanger in low temp condtion, convert operating mode from heating to
cooling, in this case, indoor and outdoor fan is off.
Oil Return System
• In heating operation, every 3 hours, changes from heating to cooling for 5 min to return the oil in piping
to compressor.
IPM Over Heat Protection
• To protect IPM overheat, down comp Hz.
Comp Overload Protection
• To protect comp from being overload, down comp Hz.
Low Pressure Protection
• If cylce pressure is low (around 0.3kgf/cm2), turn off comp and outdoor fan.
104 Multi type Air Conditioner