English
15
SALMSON 08/2014
9. Faults, causes, remedies
WARNING! Switch the pump OFF before doing
any work on it!
10. Spare parts
All spare parts must be ordered through the Wilo
customer service.
Please state all data shown on the rating plate
with each order to avoid queries and incorrect
orders.
Faults
Causes
Remedies
The pump does not start or
stops during operation
Current supply interrupted
Check fuses, cables and electrical con-
nections
Motor protection switch has tripped
Allow the pump to cool down, it will start
again automatically
Fluid temperature too high
Allow to cool down
Pump silted up or blocked
Disconnect the pump from the mains
and remove from the shaft
Remove the suction strainer and rinse
the suction strainer / impeller under run-
ning water
Pump does not switch ON/OFF
Float switch blocked or cannot move
freely
Check float switch and ensure mobility
Pump does not pump
Air in the installation cannot escape
Place the pump at an angle in water brie-
fly until the air escapes
Vent the installation / drain if necessary
Clean the degasification hole located on
the pump housing
Check the switch-off level "h1"
Water level below the intake port
If possible, submerge the pump deeper
(observe the switch-off level)
Pressure pipe / hose diameter too small
(losses too high)
Bigger dimensioning of the pressure
pipe / hose diameters
Non-return valve sticking in the
pressure port
check function
Hose kinked / check valve closed
Clear kink in hose / open check valve
Flow rate drops during operation
Suction strainer blocked /
impeller blocked
Disconnect the pump from the mains
and remove from the shaft
Remove the suction strainer and rinse
the suction strainer / impeller under run-
ning water
