GMV5 Compact Series VRF Outdoor Unit 
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(5)  Turn off vacuum pump, “LO” knob and “HI” knob, and observe the manometers value. If the pressure value 
doesn’t increase in 2 hours, the units don’t exist any leaks and air. If not, please check the units seriously and 
find leaks. 
4.5.3  Additional Refrigerant Charge 
1)The refrigerant mass of outdoor unit before installation 
The refrigerant mass (kg) 
Note: 
☆The  refrigerant  mass  of  outdoor  unit  before  installation  doesn’t  include  of  the  refrigerant  mass  of 
connection pipe. 
☆The refrigerant mass of connection pipe is determined by the actual connection pipe length. 
2)The method of computing the refrigerant mass of connection pipe based on liquid pipe 
If  the  length  of connection  pipe  is  more  than 50m,  then the refrigerant  mass  should  be charged  for  every 
excess meter. 
The refrigerant mass of connection pipe =∑the length of liquid pipe × Refrigerant mass for every excess meter 
Refrigerant mass for every 
excess meter(kg/m) 
After  confirming  that  there  is  no  leakage  from  the  system  and  compressor  is  not  at  operation,  charge 
additional R410A with specified amount to the unit through the filling opening of the liquid pipe valve of outdoor 
unit. If required additional refrigerant cannot be quickly filled because of increase of pipe pressure, then turn on the 
units at cooling mode and charge refrigerant from outdoor unit gas valve. 
4.6 Electric Wiring 
4.6.1 Wiring Precautions 
◆ Wiring should conform to national rules. All the parts, materials, electric work should be in accordance with 
local codes. 
◆ Power supplies of indoor unit and outdoor unit can be uniform or separate, but power supplies of indoor units 
must be uniform.   
◆ Rated voltage and exclusive power supply should be used.   
◆ Power cord should be fixed soundly and reliable. Never forcibly pull the power cord. 
◆ Wire size of power cord should be large enough. The damaged power cord and connecting wire should be 
replaced by exclusive cable.   
◆ All the electrical work should be performed by professional personnel as per local  law, regulation and this 
manual.