Operating instructions
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0175-168 - ENG
Rev. 2005.09
Operating Manual - SAB 202
Stopping routine
Brief stop
The compressor can be stopped at any capacity
setting. However, under normal conditions it is
recommended to reduce the capacity to a mini-
mum before stopping the compressor.
Leave all valves in their in-operation positions as
stated in the table,
Position during operation
,
Table 1, unless servicing or repair work is to be
performed.
Do not turn off power to the screw compressor unit
as the oil heater must be connected to keep the
correct oil temperature.
Shutting down for long idle period
The compressor can be stopped at any capacity
setting. However, under normal conditions it is
recommended to reduce the capacity to a mini-
mum before stopping the compressor.
The valves can be left in their in-operation posi-
tions. However, to permit servicing and repair
work, the necessary valves must be closed.
If necessary, the refrigerant can be moved to parts
of the system where no intervention will take
place. Note that the system parts which are shut
down must not be filled to the top with liquid refrig-
erant.
If the screw compressor unit is exposed to vibra-
tions during a long idle period, the compressor
and motor bearings may be damaged. To prevent
this, the motor and the compressor should be
started for a short period of time once a week, i.e.
in operation approx. 30-60 min.
Problems
Some frequently encountered errors that can be
remedied by the operator are described below.
In more complex situations, please call in skilled
personnel who have access to the appropriate
documentation.
Fault finding
The compressor does not start.
1.
No demand for chilling (refrigeration). Wait
until the temperature rises and the compres-
sor starts automatically.
2.
Incorrect set point setting. Check the set
point and, if necessary, change the setting.
3.
One of the following digital entries has not
been activated:
•
External start permission/immediate
stop and/or
•
External start/Normal stop.
4.
Oil temperature too low.
Wait until the temperature is high enough
(40°C [104°F]). Check that the heating ele-
ment is turned on and functioning properly.
5. Restarting
delay.
6.
Emergency stop activated.
If an alarm caused by a tripped monitor occurs,
call in experienced personnel who have access to
the document entitled Fault-finding
instructions.
