GEA Bock F18 - Manual (Page 18)

18
D
GB
F
E
96246-07.2014-DGbRu
5| Commissioning
5.7 Shaft seal change
5.8 Start-up
Check that the safety and protection devices (pressure switch, motor protection, electrical
contact protection measures, etc.) are all functioning properly.
Switch on the compressor and allow to run for a minimum of 10 min.
Check the oil level by: The oil must be visible in the sightglass.
5.9 Avoiding slugging
To prevent slugging:
The complete refrigeration system must be properly designed.
All components must be compatibly rated with each other with regard to output
(particularly the evaporator and expansion valves).
Suction gas superheat at the compressor input should be min. 7 - 10 K. (check the setting
of the expansion valve).
The system must reach a state of equilibrium.
Particularly in critical systems (e.g. several evaporator points), measures are recommended such
as replacement of liquid traps, solenoid valve in the liquid line, etc.
There should be no movement of coolant whatsoever while the compressor is at
a standstill.
WARNING Ensure that both shut-off valves are open before starting the
compressor!
ATTENTION If larger quantities of oil have to be topped up, there is a risk of
oil hammer effects.
If this is the case check the oil return!
ATTENTION Slugging can damage the compressor and cause refrigerant to
leak.
As changing the shaft seal involves opening the refrigerant circuit, this is recommended only if the
seal is losing refrigerant. Replacing the shaft seal is described in the spare part kit concerned.