Grundfos 97896311, Installation And Operating Instructions Manual

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