Grundfos S Series User Manual

Fault Cause Remedy
The pump head is too high.
Measure the differential pressure
and compare the value with the
pump performance curve. Remove
the blockage in the outlet pipe.
Contact Grundfos, if necessary.
The valves are closed or blocked.
The non-return valve is not operat-
ing.
Open, clean or replace the valves
as required.
There is air in the pump or the inlet
pipe.
Vent the pump or the inlet pipe. Set
a higher stop level in the pit.
The pumped liquid is too dense. Dilute the pumped liquid.
The pump is improperly connected
to the auto coupling.
Pump down the liquid level in the
pit. Lift out the pump and relocate it
on the auto coupling.
There is leakage in the pipes. Repair or replace the pipes.
The pump pit flushing system is in-
advertently activated.
Check the function of the flushing
system and repair as required.
The pump starts but stops immedi-
ately.
A clogged pump causes the motor-
protective circuit breaker to trip out.
Clean the pump.
An overheated motor causes the
thermal switches to trip out.
Allow the pump to cool. Clean the
pump.
The level switch is out of adjust-
ment or defective.
Clean or reset the level switch or
replace as required.
The pump is vibrating or emitting
excessive noise.
The pump is partly clogged by im-
purities.
Clean the pump.
Wrong direction of rotation.
Interchange two phases in the pow-
er supply to the motor.
The pump is operating outside the
specified operating range.
Re-establish proper operating con-
ditions.
The pump is defective.
Repair the pump or contact an au-
thorised workshop, if necessary.
The pump is improperly connected
to the auto coupling.
Pump down the liquid level in the
pit. Lift out the pump and relocate it
on the auto coupling.
The pump is cavitating. Clean the inlet.
The base stand, the auto coupling,
the ring stand or the guide rails are
installed incorrectly.
Install the components correctly.
The oil is watery or emulsified.
The lower mechanical shaft seal is
leaking.
Contact an authorised service work-
shop.
The oil level is low.
The upper mechanical shaft seal is
leaking.
Contact an authorised service work-
shop.
Related information
8.1 Safety instructions and requirements
39
English (GB)

Grundfos S Series Specifications

General

Brand	Grundfos
Model	S Series
Category	Water Pump
Language	English