8. Fault finding chart
PROBLEM
1. The pump does not
deliver
The motor does not
start
2. The pump does not
deliver
The motor does not
start
3. Insufficient delivery
4. Pump stops at short in-
tervals
PROBABLE CAUSE
A) No power
B) Automatic switch tripped or fuses
blow
C) Overload protection tripped
D) Faulty capacitor
E) Impeller jammed
A) Water level too low: the foot valve
is not submerged
B) Pump not filled.
Check for leaks
A) Suction lift exceeds pump suction
capacity.
Excessive flow resistance
B) Pump or pipes obstructed
C) Incorrect direction of rotation
(three-phase versions only)
A) Overload protection activation
The pump does not rotate freely.
Viscous liquid
POSSIBLE REMEDIES
A) Supply electrical power
B) Reset the switch or replace the
fuses
C) Single-phase: it will reset automati-
cally after cooling down
D) Replace the capacitor
E) Foreign matter between fixed and
rotating parts
A) The mechanical seal could be da-
maged
B) Same as per above
A) Replace suction pipe with one of
larger diameter
Reduce elbows
Remove deposits
Reduce suction lift
B) Clean or unclog
C) See point 6.2
en
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