Wilo -CronoLine IL 250 series Einbau- Und Betriebsanleitung Seite 46

8 Faults, Causes and Remedies
Faults
Pump does not start or
fails to run
Pump runs at reduced
capacity
Pump makes noise
If the fault cannot be remedied, please contact your local plumbing and heating
specialist or WILO customer services.
Installation and operating instructions
Wilo-CronoLine IL 250...
Possible cause
Pump chocked up
Loose terminals
Defect fuses
Faulty motor
Tripped overload relay
Incorrectly set trip relay
Thermal overload are
influenced by excessive
ambient temperature
Tripped PTC-relay
incorrect rotation
Discharge valve throttled too
far
Speed too low
Air in suction pipe
insufficient inlet pressure
Faulty motor bearings
Impeller scratches
Remedy
switch off power supply, take-off pump head, remove
obstruction; if motor blocked, overhaul/exchange
motor/pump head
tighten all terminals
check fuses, change defect fuses
call service
throttle hydraulic flow rate down to nominal at
discharge side of pump
reset thermal overloads to name plate FLC-value
reposition overload relay or protect by thrmal
insulation
check motor and fan cover for dirt/dust accumulation
and clean if necessary; check ambient temperature
and if necessary, ensure an ambient temperature
40 °C by forced ventilation.
check direction of rotation, if necessary
slowly open isolating valve
correct wrong terminal bridging (Y in lieu )
check and correct flange leakages, eventually vent
pipe section
raise inlet pressure, ensure minimum required inlet
pressure at suction port, check and if necessary clean
suction-side isolating valve and strainer
Arrange for pump to be inspected and, if necessary,
to be repaired by Wilo or other authorized service.
Test the contact between motor and lantern and the
contact between lantern and pumphousing. Clean it, if
necessary
Controll the fitting surface of the coupling and the
shaft and clean and oil it, if necessary.
39
English
WILO AG 08/2006