Grundfos BMP 0.2, Installation And Operating Instructions Manual

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English (GB)
8
18. Fault finding chart
Warning
Before starting work on the pump, make sure that the
electricity supply has been switched off and that it
cannot be accidentally switched on.
Fault Possible cause Remedy
1. The pump stops during
operation.
a) No water supply.
The low-pressure switch has cut out.
The level switch has cut out.
Check that the low-pressure switch functions normally
and is adjusted correctly.
Check that the minimum inlet pressure is correct. If not,
check the feed pump.
Check the water level in the water tank.
b) The fuses are blown. Check and replace the main fuses and/or fuses for
control circuit, if necessary.
c) The motor starter overload unit has tripped. Reset the starter overload, see also sections
9.2 Motor protection and 10. Start-up .
d) The magnetic coil in the motor starter/
contactor is defective (not cutting in).
Replace the coil. Check the coil voltage.
e) The control circuit has cut out or is defective. Check the control circuit and the contacts in the
monitoring devices (low-pressure switch, level switch,
etc.).
f) The motor/supply cable is defective. Check motor and cable, see section 9. Electrical
connection .
2. The pump runs, but
gives no water or
develops any pressure.
a) No or insufficient water supply at the pump
suction port.
Check that the inlet pressure during operation is at least
0 bar, see section
8.1 Inlet pressure .
Restart the pump as described in section 10. Start-up .
b) The piping system or pump is choked up. Check the piping system and pump.
c) The prefilter is clogged. Clean the prefilter.
d) The pump is worn. Replace the wear parts. Contact Grundfos Service.
e) Wrong direction of rotation. See section 10. Start-up .
3. The pump runs at
reduced capacity.
a) The pump is partly blocked by impurities. Dismantle, clean and check the pump.
Replace defective parts. Contact Grundfos Service.
b) The pump is defective. Replace defective parts. Contact Grundfos Service.
c) The prefilter is clogged. Clean the prefilter.
d) The motor speed is too low. Check the electricity supply.
Contact the electricity supply authorities, if necessary.
If a frequency converter is used, adjust the speed.