User Manual

page 15 of 27
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 ange
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 sufcient 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.