Problem
Possible causes
Remedy
Vacuum pump does
not reach ultimate
pressure
● Intake line plugged
● Intake lines are too long or
diameter is too short
● Use a greater diameter or shorter
lines.
● Lubricant soiled
● Change the lubricant.
● Intake strainer plugged
● Clean the intake strainer.
● Incorrect direction of rota-
tion of the motor
● Check direction of rotation of the mo-
tor.
● Escaping lubricant at the
radial shaft seal rings or
on the axial face seal
● Check the radial shaft seal rings or
the axial face seal.
● Have the seals affected replaced, if
necessary.
● If necessary, contact Pfeiffer Vacuum
Service.
Unusual noises during
operation
● Suction chamber dirty
● Switch off the vacuum pump immedi-
ately.
● Clean suction chamber.
● Damage to the bearing or
gear wheels
● Switch off the vacuum pump immedi-
ately.
● Contact Pfeiffer Vacuum Service.
● Damage to motor bearing
● Switch off the vacuum pump immedi-
ately.
● Change the motor.
● If necessary, contact Pfeiffer Vacuum
Service.
Excessive generation
of heat during opera-
tion
● Cooling inadequate
● Ambient temperature too
high
● Temperature of process
gas in intake too high
● Lubricant level low
● Ensure that the cooling water com-
plies with the respective require-
ments.
● Ensure that the permissible ambient
conditions are observed.
● Observe the permissible intake tem-
peratures for process gases.
● Check the lubricant level.
Lubricant is black
● Intervals for lubricant re-
placement exceeded
● Excessive generation of
heat during operation
● Change the lubricant
● Check the measures for excessive
heat generation
Tbl. 10:
Troubleshooting
Malfunctions
44/52
