LG ARUB80LT2 Installation Manual page 41

(3) Refrigerant Charged Method
After vacuum completion, primarily charge the calculated amount of additional refrigerant through the high
pressure gas pipe and the liquid pipe. If the refrigerant is not charged any more, secondarily charge the
remaining refrigerant through the low pressure gas pipe and the liquid pipe.
Vacuum and Primary charging
High pressure gas pipe
WARNING
• If the primary charging through the high pressure gas pipe and the liquid pipe is not performed after vacuum, wet
air may go into the outdoor unit. If air is mixed with the refrigerant, the refrigerant cycle may malfunction and the
unit may be damaged.
• Charging of refrigerant while the compressor is working is prohibited. Otherwise, liquid may go into the compres-
sor. It may cause faults of the compressor.
• Use a gravimeter accurate to 0.1kg.
• Pipe to be vacuum: liquid pipe, high pressure gas pipe (low pressure gas pipe is vacuumed via the HR unit).
• If other refrigerants are mixed in the original refrigerant, a refrigerant cycle may cause malfunction or damage.
• Add accurate refrigerant quantity via calculation.
Too much or too little refrigerant may cause problems
• Repeated on and off of the indoor units without charging refrigerant may cause faults of EEV.
• Since R410A is a mixed refrigerant, the required additional refrigerant must be charged in its liquid state. If the
refrigerant is charged in its gaseous state, its composition changes and the system will not work properly.
Liquid pipe
Low pressure gas pipe
Refrigerant piping installation
Secondary charging
High pressure gas pipe Liquid pipe
Low pressure gas pipe
Installation Manual 41