BGH GMV6 Technical Sales Manual page 7

Leading technology ensures stable reliability
Gree DC inverter multi VRF system is famous in the industry with the advanced technology. After ten
years of research and experiment, the technology of DC inverter multi system is more mature. From
electrical component to mechanical assembly and control technology to communication technology,
Gree DC inverter multi VRF has been upgraded comprehensively. The continued technology innovation
will surely bring more reliable and efficient services for the user.
Oil return control technology
Gree has two exclusive oil return control technologies.
New generation of oil return control
Gree new generation of oil return control technology has implanted pressure control oil return
technology, through pressure control, it controls system oil return and oil storage status of each
compressor effectively, thus improving the service life of compressor greatly.
Exclusive oil storage technoloy of compressor
Gree DC inverter unit has exclusive compressor oil storage technology and it controls the minimum oil
level required when operating the compressor by judging the parameter.
Refrigerant storage and distribution technology
Adopt non-accumulator system circuit, reduce refrigerant charge drastically and improve system
refrigerant control precision, then store the surplus refrigerant in the pipe.
Balancing oil control technology
Balancing oil technology among modules
Change the defect of traditional timer oil return; it's needless to turn off the unit to balance the oil, judge
the operation status of each module and compressor, calculate the oil reserve capacity of compressor,
adjust the operation status of compressor to realize oil balance among modules. The non-balancing oil
pipe design ensures the reliability and will not affect the capacity output of the system to maintain AC
comfort.
Oil balance technology among compressor
The refrigerant has a suction pipe in the compression working chamber of the compressor, and is
compressed and discharged into the cavity of the totally enclosed compressor, and then flows through
the refrigeration system through the exhaust pipe. According to the principle of motion fluid mechanics
and the actual amount of oil required in the working process of the compressor, the height of the oil
balance pipe is determined, the oil level of the oil pool is controlled; the minimum oil quantity required
for each compressor during operation is ensured to realize the oil balance among the compressors.
Cooling adopts the subcooling control technology to reduce cooling capacity substantially
New generation of efficient plate subcooler and condensate depression control method is adopted, the
maximum condensate depression is 35℃ , AC effect is more obvious.
Unique comfort control
ODU adopts dual electronic expansion valve for adjustment, the grade of main electronic expansion
valve is 3,000 and the subcooling electronic expansion valve is 480, precisely controlling the flow of
modules in IDU and ODU.
Considering the installation characteristic (IDU type, pipe length, fall etc.), actual startup rate of IDU,
ambient indoor and outdoor temperature, diversified system startup is realized under different ambient
temperature and installation condition, the fastest startup is completed in 75s.
Humanized operation
Auto address allocation and non-polarity communication;
Auto debugging and error detection
Five kinds of auto debugging function
Auto allocation of IDU and ODU address
Auto detection of IDU and ODU quantity
Auto detection of internal error of the unit
GMV6 DC Inverter VRF Units Technical Sales Guide
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