Hanbell RC2-AVI Series, Manual

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7.2 Parallel system applications
In the rack or parallel system, it is possible to happen the unequal-distribution of returned oil from the evaporator that
could cause low oil level in one or more of the compressors. Be sure to install the oil level switch inside each
compressors and oil flow switch installed in each oil return line to ensure the returned oil in each compressor with
normal oil level.
The basic design of the system is shown in Figure 7.8, twin compressor parallel system connections. The accessories
installed are the basic and if there are more applications or protection required, contact HANBELL or local
distributor/agent for more information or further confirmation.
Figure 7.8 Parallel system with two compressors
Item Description Item Description Item Description
1 Filter 6 Flow switch 11 Dryer
2 Compressor 7 Oil filter 12 Secondary cooler
3 Check valve 8 Oil cooler 13 Muffler
4 Sight glass 9 Expansion valve
5 Solenoid valve 10 Oil separator
7.3 Oil pump application
An additional oil pump is recommended to install to the system when the differential pressure of oil pressure and
suction pressure is less than 4 bar (for example: water cooled flooder chiller). If compressor is operating at the
mentioned condition, the failure of modulation and lubrication will be happened and will seriously damage the
compressor. Besides the installation of additional oil pump, a high – low pressure differential switch is also
recommended to install to this kind of system. Please contact Hanbell for more detailed information of oil pump.
Figure 7.9 Additional oil pump
Item Description Item Description Item Description
1 Oil pump 5 Solenoid valve 9 External oil separator
2 Compressor 6 Flow switch 10 Service valve
3 Check valve 7 Oil filter cartridge
4 Sight glass 8 Oil cooler