GMV DC Inverter VRF 
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4) Manifold attached foam can not be taken as insulating material. 
5) When wrapping the tape, the later circle should cover half of the former one. Don’t 
wrap the tape so tightly, otherwise the insulation effect will be weakened. 
6) After wrapping the pipe, adopt sealing material to completely fill the hole so as to 
prevent wind and rain from entering the room. 
4.3.4 Support and protection for pipeline 
(1) Support should be made for hanging connection pipe. Distance between each support 
can not be over 1m. 
(2) Protection towards accidental damage should be made for outdoor pipeline. When the 
pipeline exceeds 1m, a pinch board should be added for protection. 
 
4.4 Air Purging and Refrigerant Charge 
4.4.1 Air purging 
(1) Confirm outdoor liquid and gas valves are closed. Air puring from the nozzel located on 
liquid and gas valves by vacuum pump.See Fig. 4.4.1. 
(2) When there are more than 2 outdoor units, air purging from the nozzel located on the 
oil balance valve. Confirm outdoor oil balance valves are closed. See Fig. 4.4.2.   
 
Fig. 4.4.1                                                                           Fig. 4.4.2 
4.4.2 Additional refrigerant charging 
Outdoor unit has been charged refrigerant before delivery.   
Charge additional refrigerant for field-installed connecting pipe. If the pipeline is longer 
than 1m, please refer to the following table for charging amount of refrigerant. (Liquid pipe 
prevails) 
How much additional refrigerant should be charged. 
Total refrigerant charging amount R= Pipeline charging amount A + ∑charging amount B 
of every module