Grundfos Unilift CC 5 M1, Инструкция по эксплуатации

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2. Fault finding
Switch off the electricity supply before dismantling the pump.
Fault Cause Remedy
1. Pump does not
run.
a) Electricity supply switched off. Switch on the electricity supply.
b) Fuses in installation blown. Replace defective fuses.
c) The pump thermal switch has tripped out. The thermal switch restarts the pump when the motor has
cooled to normal temperature.
d) The main winding is defective, see 5. Winding resist-
ances.
Replace the motor, see 4.1 Removing the motor.
2. The pump does
not run, but hums.
a) The capacitor is defective. Replace the capacitor, see 4.2 Replacing the capacitor .
Replace the motor, 4.1 Removing the motor.
b) The auxiliary winding is defective.
3. The pump stops
after short time of
operation (ther-
mal switch tripped
out).
a) The pumped liquid temperature is too high. The pump restarts automatically after sufficient cooling.
b) Pump partly blocked by impurities or blocked. Clean the pump, see 3.2 Cleaning the impeller .
c) Water level too low when the pump is started. The
pump cannot self-prime.
Move the pump to a position with higher water level or add
water until the pump starts sucking.
4. Pump runs but
gives insufficient
water.
a) Pump is partly blocked by impurities. Clean the pump, see 3.2 Cleaning the impeller .
b) Discharge pipe/hose partly blocked by impurities. The
hose may be sharply bent.
Check and clean the non-return valve, if fitted.
c) Impeller, bottom part or diaphragm defective. Replace defective parts.
5. Pump runs but
gives no water.
a) Pump is blocked by impurities. Clean the pump, see 3.2 Cleaning the impeller .
b) Non-return valve in discharge pipe/hose blocked in
closed position or blocked by impurities. The hose may
be sharply bent.
Check the non-return valve. Clean or replace the valve, if
necessary.
c) Pumps with float switch:
The pump does not stop because the free cable length
of the float switch is too long.
Reduce the free cable length.