KNF N 143 AN.12 E, Operating And Installation Instruction

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Diaphragm Pumps N 143/186.12 Troubleshooting
Translation of original Operating and Installation Instructions, english, KNF 121610-121613 07/16 25
9. Troubleshooting
DANGER
Extreme danger from electrical shock!

Disconnect the pump power supply before working
on the pump.

Make sure the pump is de-energized and secure.

Check the pump (see Tab. 16 and 17).
Pump does not transfer
Cause Fault remedy
Pump is not connected with the
power source.

Connect pump with the power source.
No voltage in the power source

Check room fuse and switch on if necessary.
Thermal switch has operated
following to over-heating.

Disconnect pump from mains.

Allow pump to cool.

Trace cause of over-heating and eliminate it.
Connections or lines blocked.

Check connections and lines.

Remove blockage.
External valve is closed or filter
is clogged.

Check external valves and filters.
Condensate has collected in
pump head.

Detach the condensate source from the pump.

Flush the pump under atmospheric conditions some minutes
with air (if necessary for safety reasons: with an inert gas).
Working diaphragm or valve
plate are worn.

Replace working diaphragm, safety diaphragm andvalve
plate (see chapter 8.3).
Tab. 16
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
Working diaphragm has broken.

Immediately shut down pump.

Check whether the pressure in innerspace (evacuated)
between working diaphragm and safety diaphragm has ele-
vated. If the pressure has elevated, replace working dia-
phragm and safety diaphragm (see chapter 8) before further
operating the pump.
Condensate has collected in
pump head.

Detach the condensate source from the pump.

Flush the pump under atmospheric conditions some minutes
with air (if necessary for safety reasons: with an inert gas).
There is gauge pressure on
pressure side and at the same
time vacuum or a pressure
above atmospheric pressure on
suction side.

Change the pressure conditions.
Pneumatic lines or connection
parts have an insufficient cross
section.

Disconnect pump from system to determine output values.

Eliminate throttling (e.g. valve) if necessary.

Use lines or connection parts with larger cross section if
necessary.