Hanbell RC2-AV Series, Manual

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7.5 Important notes about applications of compressor
1. Pump down
Do not pump down the compressor on the chiller as a routine operation. Only pump down for urgent maintenance
or a long term shut down. Because pump down will cause extremely high temperature in the compression chamber
and overheat of the motor as well due to less amount of refrigerant in the suction side. When doing the pump down,
be sure to take notice of the items listed below:
a. Pump down should be done once each time. Repeated pump down may damage the compressor.
b. The minimum suction pressure when pumping down should is 0.5kg/cm2.
c. Time for pumping down should be shorter than 15 seconds.
d. When doing pump down, notice the high discharge temperature. It should not go over 110
℃
.
e. Notice oil level of the compressor and the sound of running as well. If there is any abnormal value or situation,
emergently stop pumping down.
2. Low pressure receiver
When a compressor operates in the following application conditions, installation of a low pressure receiver is
recommended in order to prevent massive liquid refrigerant from returning to the compressor under momentary
changes of operation condition.
●
Heat pump
●
Parallel system
●
system with long piping
●
operating in the low ambient temperature area
●
system heating load varies extremely