9 Malfunctions
WARNING
Danger to life from electric shock in the event of a fault
In the event of a fault, devices connected to the mains may be live. There is a danger to life from
electric shock when making contact with live components.
► Always keep the mains connection freely accessible so you can disconnect it at any time.
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
Damage from incorrect maintenance work
Unprofessional work on the vacuum pump will lead to damage for which Pfeiffer Vacuum accepts no
liability.
► Ensure that only the following categories of persons are authorized to perform servicing tasks:
– Pfeiffer Vacuum employees with corresponding qualifications.
– Persons who have undergone training from Pfeiffer Vacuum and have subsequently taken
part in refresher courses at intervals of no more than every two years.
– Persons who have been awarded official certification in accordance with Article 14 (6) Betr-
SichV (Ordinance on Industrial Safety and Health).
► We recommend taking advantage of our service training offering.
Problem
Possible causes
Remedy
Roots pump will not start
up
● Mains voltage is miss-
ing or the incorrect op-
erating voltage is
present
● Check mains voltage
● Check mains fuse protection
● Check motor switch
● Thermal protection
switch has triggered
● Detect and fix the cause; allow roots
pump to cool down if necessary
● Suction chamber con-
taminated
● Clean the suction chamber; contact
Pfeiffer Vacuum Service if necessa-
ry
● Gear (gear wheels)
damaged
● Switch the roots pump off immedi-
ately; contact Pfeiffer Vacuum Serv-
ice
● Bearing damage
present
● Change the bearing; contact Pfeiff-
er Vacuum Service if necessary
● Motor faulty
● Replace the motor
Roots pump switches off
after a while after being
started
● Thermal protection
switch of the motor has
triggered
● Detect and fix the cause of over-
heating; allow the motor to cool
down if necessary
Roots pump/pumping sta-
tion does not reach ulti-
mate pressure
● Suction chamber dirty
● Cleaning the suction chamber
● Lubricant soiled
● Changing the lubricant
● Backing pump oper-
ates incorrectly
● Check the backing pump
● Leak in system
● Check the system for leaks; carry
out a leak test if necessary
● Fix leak
For pumps with overflow
valve:
● Overflow valve does
not close completely
● Check the overflow valve; replace if
necessary
Malfunctions
48/60
