Diaphragm liquid pump NF 25, NFB 25
Troubleshooting
KNF Flodos AG BA_NF25_NFB25_EN_07_159615
Translated from the Original Operating and Installation Instructions
23
Flow rate, suction head or pressure head is too low
The pump does not achieve the performance stated in the technical data or on the data sheet.
Possible cause
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
(see Chapter 8.2)
Viscosity of the transferred
medium is too high
Contact KNF
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
Tab. 10
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).
Flush the pump to clear the pump head of any hazardous or
aggressive liquids (see Chapter 8.2.1).
Dismantle the pump.
Clean the pump (see Chapter 8.2.2).
Send the pump, with completed decontamination declaration
(see Chapter 10), to KNF customer service stating the nature
of the transferred medium.