Fault Finding; Pump Set With Diesel Engine - Grundfos Fire HSEF FM Europe Series Installation And Operating Instructions Manual

13. Fault finding

13.1 Pump set with diesel engine

Warning
Before starting service work, make sure that the
pump set cannot accidentally start.
Fault Cause
1. Pump delivers no or a) Air in suction pipe.
too little water.
b) Pump draws in air due to defective seals.
c) Counter-pressure is too high.
d) Inlet pressure is too low.
e) Suction pipe or impeller is blocked.
2. Pump makes too a) Inlet pressure is too low (cavitation).
much noise. Pump
runs unevenly and
vibrates.
b) Air in suction pipe.
c) Impeller out of balance.
d) Inner parts worn.
e) Pump stressed by the pipework.
f)
g) Defective coupling.
h) Foreign bodies in the pump.
3. Leaking pump a) Pump stressed by the pipework.
housing.
b) Pump housing gaskets or flange gaskets
4. Leaking shaft seal. a) Shaft seal dirty or seized up.
b) Shaft seal defective.
c) Shaft surface or shaft sleeve defective.
5. Too high pump a) Air in pump.
temperature.
b) Inlet pressure is too low.
c) Bearings lubricated with too little, too
d) Pump bearing seat stressed by pipework.
e) Axial pressure too high.
22
Defective bearings.
defective.
much or unsuitable lubricant.
Remedy
Fill priming tank with water and vent pump. Make sure that
the suction pipe has been installed according to section
6.5 Pipe connection.
Check pipe and pump housing gaskets, and replace if
necessary.
Check the sprinkler system for impurities and blockages.
Make sure that the storage tank is filled with water and that
the conditions in section 15.6 Minimum inlet pressure are
complied with.
Clean the suction pipe and pump.
Make sure that the storage tank is filled with water and that
the conditions in section 15.6 Minimum inlet pressure are
complied with.
Fill priming tank with water. Vent pump. Make sure that the
suction pipe has been installed according to section 6.5 Pipe
connection.
Clean the impeller and remove foreign particles.
Replace defective parts. See service instructions for the
pump.
Mount the pump so that it is not stressed. Support the pipes.
See section 6.5 Pipe connection.
Replace bearings.
Replace the coupling.
Clean the pump and remove foreign bodies.
Mount the pump so that it is not stressed. Support the pipes.
See section 6.5 Pipe connection.
Replace defective gaskets.
Check and clean the shaft seal.
Replace the shaft seal. See service instructions for the pump.
Replace the shaft or the shaft sleeve. See service instructions
for the pump.
Fill the priming tank with water and vent the pump.
Make sure that the storage tank is filled with enough water
and that the conditions in section 15.6 Minimum inlet
pressure are complied with.
Replenish, reduce or replace the lubricant.
Mount the pump so that it is not stressed. Support the pipes.
Check the alignment of the pump, and correct, if necessary.
See section 6.5 Pipe connection and 6.4 Alignment.
Check the relief holes of the impeller and the lock rings on the
suction side.