KNF N 811, Translation Of Original Operating And Installation Instructions

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Diaphragm vacuum pump N 89/N 811/N 814/N 815 Troubleshooting
Translation of original Operating and Installation Instructions, english, KNF 121242-121509 04/20 29
9. Troubleshooting
DANGER
Extreme danger from electrical shock!

Disconnect the pump power supply before work-
ing on the pump.

Make sure the pump is de-energized and se-
cure.

Check the pump (see Tab. 15 and Tab. 16).
Pump does not transfer
Cause Fault remedy
For pumps with a thermal
switch:
Thermal switch has opened due
to over-heating of motor.

Disconnect pump from power supply.

Allow pump to cool.

Identify and eliminate cause of overheating.
Connections or hoses are
blocked.

Check connections and hoses.

Remove blockage.
External valve is closed or filter
is clogged.

Check external valves and filters.
Condensate has collected in the
pump head.

Detach the condensate source from the pump.

Flush the pump with air (or with inert gas if required for safe-
ty reasons) under atmospheric conditions for a few minutes.
Diaphragm or valve
plates/sealings are worn or de-
fective.

Replace diaphragm and valve plates/sealings (see
Chapter 8.3).
Tab. 15
Flow rate, pressure or vacuum too low
The pump does not achieve the output specified in the Technical data or the data sheet.
Cause
Fault remedy
Condensate has collected in the
pump head.

Detach the condensate source from the pump.

Flush the pump with air (or with inert gas if required for safe-
ty reasons) under atmospheric conditions for a few minutes.

Cross-section of pneumatic
hoses or connectors too narrow
or restricted.

Disconnect the pump from the system and determine output
values.

Remove restriction (e.g. valve) if necessary.

If applicable, use larger-diameter hoses or connectors.
Leaks in connections, hoses or
pump head.

Repair leaks.
Pump head components are
soiled.

Clean head components.
Diaphragm or valve
plates/sealings are worn or de-
fective.

Replace diaphragm and valve plates/sealings (see
Chapter 8.3).
Tab. 16