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Troubleshooting
P1700040
29
7
Troubleshooting
Only manufacturing firm and authorized service workshops may work on the pump and their
accessories during the warranty period.
Trouble
Cause
Remedy
by:
with:
Vacuum pump
does not start
No power supply
Qualified
electrician
Check electrical installation
Motor defective
Service
workshop
Exchange
Coupling defective
Repair and/or exchange
Starting temperature too low
User
Put vacuum pump in a warm
place corresponding
to the starting temperature
Oil is resinous after too long storage
User or
Service
workshop
General maintenance / cleaning
Vacuum pump
does not
generate a
vacuum
Ultimate pressure few mbar
or atmospheric pressure, oil shortage
User
Top-up oil
Oil is dirty
Operate with gas ballast, or
perform oil change with flushing
Oil supply to pump unit interrupted
or reduced
User
Check that the oil circulation
is functioning, measure the oil
pressure at operating
temperature, 1
– 1.2 bar
overpressure, check that the
pipes are clear and have no
leaks
Gas ballast valve open
User
Close the gas ballast valve
Shaft seals defective
User or
Service
workshop
Exchange
Work or pressure control valve
defective
Exchange
Intake valve defective
Repair
Oil supply to pump aggregate reduced,
Oil superimposition interrupted
by work valve
Repair
Built-up pressure in the oil casing too
high because of exhaust gas pipe
or oil mist filter
User or
Service
workshop
Check exhaust pipe, change
filter insert
Vacuum pump
runs very
loudly
Motor, rotary vanes and/or shaft seal
rings defective,
rotary vane spring broken
Repair and/or exchange
Vacuum pump
runs hot
Vacuum pump oil supply interrupted
Check that the oil circulation
is functioning, measure the oil
pressure at operating
temperature, 1
– 1.2 bar
overpressure, check that the
pipes are clear and have no
leaks
Oil with too low a viscosity used
Oil change
Ambient temperature around vacuum
pump too high
User
Change location
Motor defective
User or
Service
workshop
Exchange
Built-up pressure in the oil casing too
high (
0.5 bar)
Check exhaust pipe, change
filter insert
Heavy loss of
oil
Through oil mist emission:
work or pressure control valve
defective
Exchange
Because of leak from oil casing:
shaft seal defective, oil casing seals
defective
Repair and/or exchange
Vacuum pump
is not vacuum-
tight when
Intake valve defective
Repair and/or exchange
Shaft seal ring on the drive side
or oil pump defective
Repair and/or exchange