Diaphragm Pumps NMP850 HP
Troubleshooting
KNF Micro BA321648-321651 NMP850_HP-EN 0921.docx
Translation of original Operating and Installation Instructions, English
17
8. Troubleshooting
Pump does not work
Cause
Fault remedy
Pump not connected to power
supply
➔
Connect pump to power
supply
Power supply is not switched on
➔
Switch on power supply
Thermal switch or pump elec-
tronics have responded
➔
Disconnect pump from mains power supply.
➔
Allow pump to cool.
➔
Identify and eliminate cause of overheating/overload
Connections or pipes are
blocked.
➔
Check pipes and connections.
➔
Remove blockage.
External valve is closed or filter
is blocked
➔
Check external valves and filters.
Diaphragm, valves or gaskets
are worn out
➔
Service according 7.3
➔
Contact customer service
Tab. 13
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
Components in the system
connected to the suction and
pressure sides, such as hoses,
valves or filters, are causing too
much resistance
➔
Modify installation, check the cross-sections of components
Hose connections are not leak
tight
➔
Secure transition joints between hose and hose connections
➔
with clamps or clamping elements
Particles in the pump
➔
Clean the pump head, install suction-side filter if required
Incorrect interchange of pres-
sure and suction line connec-
tions
➔
Remove pressure and suction lines and reconnect correctly
The pump parts are not re-
sistant to the medium to be
transferred
➔
Replace the pump head with a compatible version
Diaphragm, valves or gaskets
are worn out
➔
Service according 7.3
➔
Contact customer service
Tab. 14
Fault cannot be rectified
If you are unable to identify any of the above causes, please send
the pump to KNF customer service (see address on last page).
1. Isolate the pump from the power supply and remove the pump
from the system.
2. Clean the pump (see Chapter 7.2.1)
3. Send the pump, with completed decontamination declaration
(see Chapter 9), to KNF customer service stating the nature of
the transferred medium.
