Gree Ultra Heat GMV-VQ72W/A-F, Service Manual

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Ultra Heat GMV VRF Technical Service Manual_Heat Recovery Serial INSTALLATION
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Before connecting the flare opening of the pipe to the IDU, connect the pressure regulator valve on
the nitrogen cylinder to the liquid pipe in the outdoor pipe system. Regulate the nitrogen pressure to
about 5 kgf/cm² and blow nitrogen into the pipe for 1 minute. Repeat this operation for three times till the
dirt and water are discharged. After cleaning the liquid pipe, perform the same operation to clean the gas
pipe.
Perform an air-tightness test and a vacuum test to the entire refrigerant pipe system after the
construction is finished.
There must be a secure distance between pipes. Pipes in different types must be fixed separately.
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When all of the pipes of indoor unit finish welding, dry nitrogen must be used to blow and clean the
pipes. Otherwise, the remaining substance in pipeline will cause blockage or leakage to the system (e.g.
electronic expansion valve), which result in abnormal operation or even damage the compressor.
1.3.8 Refrigerant pipe installation
During refrigerant pipe installation, ensure a distance above 500 mm (19.7inch) between the pipe
and the electric box of the unit for maintenance. In a case when the space is not enough, the final piping
way must be determined by the technical personnel.