22 22
ENGLISH
• Thermal cutout protection setting or
fuses not suitable = check protection
devices with respect to rated current
of pump
• Power cable damaged = replace
component
• Motor damaged = replace component
The pump starts up but does not deliver
liquid
• Pump is not primed = repeat the
"pump priming" procedure
• The pump takes in air = check the
liquid level, operation of the foot valve
and the suction pipeline
• The foot valve is blocked in the closed
position = replace or clean the valve
• For self-priming pumps only: The
liquid column above the check valve
on the delivery pipeline prevents
self-priming of the pump = drain the
delivery pipeline Check that check
valve does not retain liquid in the
delivery pipeline Repeat the start-up
procedure.
Pump performance is reduced
• Pipelines obstructed = check pipelines
• Pump is not primed correctly = repeat
the "pump priming" procedure
• The pressure switch setting is low =
adjust the pressure switch
• For self-priming pumps only: the in-
ternal valve has not closed = gradually
close a valve until there is a visible in-
crease in pressure or flow. Then open
the valve gradually until the required
flow rate is reached.
Pump performance is unstable
• Pump suction pressure too low or
cavitation = check the pump inlet
conditions
• Suction pipe is partially obstructed
with impurities = clean the suction
pipe
• Leak from suction pipe = repair or
replace suction pipe
• air in suction pipe = bleed the suc-
tion pipe, repeat the "pump priming"
instructions
• For self-priming pumps only: The dif-
ferential pressure inside the pump is
too low = gradually close a valve until
delivery pressure stabilizes and the
noise level is reduced
The pump rotates in the opposite direc-
tion when shut down
• Foot valve or check valve defective or
blocked in the open position = remove
and clean or replace the valves
• Leak from suction pipe = remove and
repair suction pipe
The pump starts and stops frequently
• The membrane inside the tank is
damaged = replace the internal mem-
brane of the tank
• The gas pressure in the expansion
tank is incorrect with respect to the
pressure switch setting = adjust the
gas pressure to approximately the
pump intervention pressure minus
10%.
• Leak from foot valve = clean or repla-
ce the foot valve.
The pump does not stop
• The pressure switch setting is incor-
rect (too high) = adjust the pressure
switch to within the pump pressure
limits
• air in suction pipe = bleed the suc-
tion pipe, repeat the "pump priming"
instructions
To Next Page
Loading...
