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Documents are only to be used and distributed completely and unchanged. It is strictly the users´ responsibility to check carefully
the validity of this document with respect to his product. Manual-no.: 999198 / 29/09/2009
Troubleshooting
Fault
Possible cause
Remedy
❑
Pump does not start or
stops immediately.
➨
Knob for motor speed is
turned to the left stop?
✔
Turn the knob to the right.
➨
Supply voltage is missing or
too low?
✔
Check or connect the supply
voltage; check the mains
fuse.
➨
Overpressure in the exhaust
line?
✔
Open exhaust line, ensure a
free (pressureless) outlet line
➨
Motor overloaded?
✔
Allow motor to cool. Identify
and eliminate the cause of
failure.
➨
VACUU•BUS fuse has been
triggered, e.g. load in the
VACUU•BUS system too high
or short circuit in valves?
✔
Remove VACUU•BUS com
-
ponents (e.g. valves). The
fuse is self-resetting.
❑
Pump does not achieve
ultimate vacuum or nor-
mal pumping speed.
➨
Centring ring at a small flange
connection not correctly posi-
tioned or leak in the pipeline
or vacuum system?
✔
Check pump directly - con-
nect vacuum gauge directly
at pump inlet - then check
connection, pipeline and
vacuum system if necessary.
➨
Long, narrow vacuum line?
✔
Use lines with larger dia-
meter, length as short as
possible.
➨
Pump has been exposed to
condensate?
✔
Allow pump to run for some
minutes with atmospheric
pressure at the inlet.
➨
Deposits have been formed
inside the pump?
✔
Clean and inspect the pump
heads.
➨
Diaphragms or valves defec-
tive?
✔
Replace diaphragms and/or
valves.
➨
Outgassing substances or
vapour generated in the pro-
cess?
✔
Check process parameters.
➨
Pump temperature too high
(reduced motor speed)?
✔
Ensure sufficient cooling
of the pump or reduce inlet
pressure.
❑
Pump too noisy.
➨
Loud exhaust noise?
✔
Connect hose or silencer to
pump outlet.
➨
Diaphragm crack or dia-
phragm clamping disc loose?
✔
Perform maintenance.
➨
Other than above mentioned
causes?
✔
Contact local distributor.
❑
Pump seized.
✔
Contact local distributor.
