Fault Finding; Service Documentation; Disposal - Grundfos CM Instrucciones De Instalación Y Funcionamiento

14. Fault finding

Warning
Before removing the terminal box cover, make sure that the power supply has been switched off.
The pumped liquid may be scalding hot and under high pressure. Before any removal or dismantling of the pump, the
system must therefore be drained, or the isolating valves on either side of the pump must be closed.
Fault
1. The pump does not run.
2. Motor-protective circuit breaker has tripped
(trips out immediately when supply is
switched on).
3. The motor-protective circuit breaker trips out
occasionally.
4. The motor-protective circuit breaker has not
tripped out, but the pump is inadvertently
out of operation.
5. The pump performance is unstable.
6. The pump runs, but gives no water.
7. The pump runs backwards when switched
off.
8. The pump runs with reduced performance.

15. Service documentation

Service documentation is available on www.grundfos.com >
International website > WebCAPS > Service.
If you have any questions, please contact the nearest Grundfos
company or service workshop.
12
Cause
a) Supply failure.
b) Fuses are blown.
c) Motor protection tripped.
d) Control-current circuit defective.
a) Fuses are blown.
b) Contacts of the motor-protective circuit breaker
or magnet coil defective.
c) Cable connection is loose or faulty.
d) Motor winding is defective.
e) The pump is mechanically blocked.
f) The setting of the motor-protective circuit
breaker is too low.
a) The setting of the motor-protective circuit
breaker is too low.
b) Periodic supply failure.
c) Periodically low voltage.
a) See 1. a), b), d) and 2. e).
a) Pump inlet pressure too low.
b) Suction pipe is partly blocked by impurities.
c) Leakage in suction pipe.
d) Air in suction pipe or pump.
a) Pump inlet pressure too low.
b) The suction pipe is partly clogged by impurities. See 5. b).
c) The foot or non-return valve is stuck in its
closed position.
d) Leakage in suction pipe.
e) Air in suction pipe or pump.
a) Leakage in suction pipe.
b) Foot or non-return valve defective.
c) The foot valve is stuck in completely or partly
open position.
a) Wrong direction of rotation.
b) See 5. a), b), c), d).

16. Disposal

This product or parts of it must be disposed of in an
environmentally sound way:
1. Use the public or private waste collection service.
2. If this is not possible, contact the nearest Grundfos company
or service workshop.
Remedy
Turn on the switch.
Check cables and cable connections for defects and
loose connections.
Check cables and cable connections for defects, and
replace the fuses.
See 2. a), b), c), d), e), f).
Repair or replace the control-current circuit.
See 1. b).
Replace the contacts of the motor-protective circuit
breaker, the magnet coil or the entire motor-protective
circuit breaker.
Check cables and cable connections for defects, and
replace the fuses.
Repair or replace the motor.
Switch off the power supply, and clean or repair the
pump.
Set the motor-protective circuit breaker according to
the rated current of the motor (I ). See nameplate.
1/1
See 2. f).
See 2. c).
Check cables and cable connections for defects and
loose connections.
Check that the supply cable of the pump is correctly
sized.
Check the inlet conditions of the pump.
Remove and clean the suction pipe.
Remove and repair the suction pipe.
Vent the suction pipe/pump.
Check the inlet conditions of the pump.
See 5. a).
Remove and clean, repair or replace the valve.
See 5. c).
See 5. d).
See 5. c).
See 6. c).
See 6. c).
Three-phase pumps only:
Switch off the power supply with the external circuit
breaker, and interchange two phases in the pump
terminal box. See also section 9.2 Checking the
direction of rotation.
Subject to alterations.