Diaphragm pump N87.9 EX
Troubleshooting
Translation of Original Operation and Installation Instruction, english, KNF 323252 04/21
35
Flow rate, pressure or vacuum too low
The pump does not reach the performance stated in the technical data or data
sheet.
Cause
Fault remedy
Condensate has collected in the
pump head.
à
Separate the source of the condensation from the
pump.
à
Flush the pump with air at atmospheric pressure
for a few minutes (if necessary for safety reasons:
with an inert gas).
à
Install the pump at the highest location in the sys-
tem.
There is overpressure on the pres-
sure side and at the same time
vacuum or pressure above atmo-
spheric pressure on the suction
side.
à
Change the pneumatic conditions.
Pneumatic lines or connection
parts have insufficient cross sec-
tion or are throttled.
à
Disconnect the pump from the system to deter-
mine the output values.
à
Eliminate any throttling (e.g. valve) if necessary.
à
Use lines or connection parts with a larger cross
section if necessary.
Leaks occur at pneumatic connec-
tions, lines or pump head.
à
Eliminate the leaks.
Pneumatic connections or lines are
completely or partially clogged.
à
Check the pneumatic connections and lines.
à
Remove any parts and particles that are causing
blockages.
Head parts are soiled.
à
Clean the head components.
Diaphragm or valve plate/seal is
worn.
à
Change the diaphragm and the valve plate/seal
(see Chapter
Working diaphragm broken
à
Stop the pump immediately.
Pump exhibiting changed running
noises and vibrations.
à
Stop the pump immediately.
à
Contact KNF Customer Service.
Tab.20
Pump exhibiting changed running noises and vibrations.
Cause
Fault remedy
Pump bearing worn or defective.
à
Determine the cause.
à
Contact KNF Customer Service.
Motor worn or defective.
à
See operating instructions for the motor.
Tab.21