9 Malfunctions
CAUTION
Danger of burns on hot surfaces
In the event of a fault, the surface temperature of the vacuum pump can increase to above 105 °C.
► Allow the vacuum pump to cool down before carrying out any work.
► Wear personal protective equipment if necessary.
NOTICE
Danger of property damage from improper maintenance
Unprofessional work on the vacuum pump will lead to damage for which Pfeiffer Vacuum accepts no
liability.
► We recommend taking advantage of our service training offering.
► When ordering spare parts, specify the information on the nameplate.
Problem
Possible causes
Remedy
Vacuum pump will not
start up
● Mains voltage is missing or
the incorrect operating volt-
age is present
● Check the mains voltage.
● Check the mains fuse.
● Check the motor switch.
● The circuit breaker trips;
the circuit breaker may be
of the wrong type
● Check the terminal connection in the
motor terminal box
● Check the circuit breaker type; use
type “K” with slower tripping charac-
teristic
● Thermal protection switch
has triggered
● Determine the cause and eliminate
the fault.
● Allow the vacuum pump to cool if
needed.
● Suction chamber contami-
nated
● Clean suction chamber.
● If necessary, contact Pfeiffer Vacuum
Service.
● Gear (gear wheels) dam-
aged
● Switch off the vacuum pump immedi-
ately.
● If necessary, contact Pfeiffer Vacuum
Service.
● Bearing damage present
● Have the bearing changed.
● Contact Pfeiffer Vacuum Service.
● Motor faulty
● Change the motor.
Vacuum pump
switches off after a
while after being start-
ed
● Thermal protection switch
of the motor has triggered
● Fore-vacuum pressure
possibly too high
● Determine the cause of the overheat-
ing and eliminate the fault.
● Check the fore-vacuum pressure
● Allow the motor to cool if necessary
Vacuum pump/pump-
ing station does not
reach ultimate pres-
sure
● Suction chamber dirty
● Clean suction chamber
● Lubricant soiled
● Change the lubricant
● Backing pump operates in-
correctly
● Check the backing pump
● Leak in system
● Examine the system for leaks and, if
necessary, carry out a leak test.
● Eliminate leaks.
● Loss of lubricant at the lu-
bricator or the radial shaft
seal rings
● Check the radial shaft seal rings.
● Have the radial shaft seal rings re-
placed if necessary.
● If necessary, contact Pfeiffer Vacuum
Service.
● Overflow valve does not
close completely
● Check the overflow valve; replace if
necessary
Malfunctions
40/52
