Hanbell RC2-100AF, Manual

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Discharge bypass line
Discharge bypass line is widely used to reduce the pressure differential between low and high pressure side. In
this kind of application, the discharge check valve is normally installed on the oil separator outlet which can isolate
the high pressure side (condenser) from the oil separator side. Because a suction check valve is usually installed
on the compressor
’s suction port, the pressure in oil separator and compressor will be equalized in the end. Using
a discharge by pass line which connects the oil separator and the suction pipe line can reduce the pressure in the
oil separator to ensure a light-duty-start of the compressor.
Oil cooler
Oil cooler is often used to control the oil temperature at desire setting. The proper oil temperature can ensure the
oil viscosity and lubricity and can provide necessary help for chamber cooling and discharge temperature control.
Because the oil temperature in the beginning of system running is not high (normally around 20 to 30
℃
), oil
cooling will not be necessary during this period. By pass the oil at oil cooler can help to increase the oil
temperature faster to the desired temperature and having system stabilized. When the oil temperature reaches
the setting, oil cooler can start to work to control the oil temperature for the system.
Oil cooler should be installed as close as possible to the compressor and preferably below the level of compressor
/ oil separator to avoid gas pads or any drainage of oil into the oil separator during standstill.
Oil filter
Oil filter is usually installed on the oil line. User should consider installing a pressure differential protector which
helps to monitor the pressure drop between both sides of oil filter. When oil pressure drop reaches 1 to
1.2
2
/ cm kg
, this means the oil filter is clogged by debris or dirt and user should clean it to ensure sufficient oil
supply to compressor. Insufficient oil supply leads to severe damage to internal moving parts and malfunction of
capacity control.
Oil pump
When pressure differential between main oil inlet port and suction side is less than 4
2
/ cm kg
, it means using an
oil pump for the oil circuit becomes important. The oil pump should start and stop simultaneously with the
compressor to ensure sufficient oil supply.
Oil return valve (for fine/secondary oil separator)
In the case of using fine/secondary oil separator, an oil return line from the bottom of fine/secondary oil separator
to compressor
’s suction side is very important. The control of oil return valve can be simply by a solenoid valve
with a regulation valve or using a floating ball as a trigger and be opened only after the compressor starts. User
should adjust the flow volume during the initial start up to ensure a steady oil return to the system.
Pressure regulation valve
Pressure regulation valve is suggested to be installed on the exit of the external oil separator when oil pump is not
applied in the system. With its help, the oil pressure can be built up quickly to ensure sufficient oil supply to