Grundfos SB Serie Instrucciones De Instalación Y Funcionamiento página 12

Fault
2. The pump runs but
gives no water.
3. The pump runs at
reduced
performance.
4. Frequent starts
and stops.
12
Cause
a) The outlet valve is closed.
b) No water or too low water level in
tank.
c) The non-return valve is stuck in its
closed position.
d) The inlet strainer is clogged.
e) The pump is defective.
a) The valves in the outlet pipe are
partly closed or blocked.
b) The outlet pipe is partly blocked by
impurities.
c) The non-return valve in the outlet
pipe is partly blocked.
d) The pump and outlet pipe are
partly blocked by impurities.
e) The inlet strainer is clogged.
f) The pump is defective.
g) Leakage in the pipework.
h) The outlet pipe is defective.
i) Undervoltage has occurred.
a) The float switch has not been
adjusted correctly.
b) The non-return valve is leaking or
stuck half-open.
c) The supply voltage is unstable.
d) The motor temperature is too high. Check the water temperature.
e) The pump is blocked.
f) Leakage in the pipework.
Remedy
Open the valve.
Increase the installation depth of the
pump. The maximum installation depth is
10 metres. Reduce the pump
performance, or replace the pump by a
pump with a lower performance.
Pull out the pump, and clean or replace
the valve.
Pull out the pump, and clean the inlet
strainer with a brush and a water jet.
Repair or replace the pump.
Check and clean or replace the valves.
Clean or replace the pipe.
Clean or replace the valve.
Pull out the pump. Check and clean or
replace the pump. Clean the pipes.
Clean the inlet strainer.
Repair or replace the pump.
Check and repair the pipework.
Replace the outlet pipe.
Check the power supply.
Adjust the float switch to ensure suitable
time between the cutting-in and cutting-
out of the pump.
Clean or replace the non-return valve.
See figures 1 and 2 on pages
263.
SB: (149)
SBA: (151)
Check the power supply.
Check and clean the pump.
1. Switch off the power supply to the
pump.
2. Remove the eight screws (84b) with a
cross-head screwdriver.
3. Remove the pump base (56). See
figures 1 and 2 on pages
263.
4. Clean the inlet strainer and hydraulic
parts with a brush and a water jet.
5. Reassemble the pump.
Check and repair the pipework.
262 and
262 and