10.2 The pump(s) does/do not run
Cause
No power supply.
None of the indicator lights are on.
The ON-OFF-AUTO selector is in position OFF.
Control circuit fuses are blown.
The motor or supply cable is defective or the
connections have become loose.
10.3 The sensor signal is out of range
All pumps are started, and the high level alarm is on.
Cause
Not all outlet valves are open.
There is a blockage in the tank or pump.
The pump is not vented correctly. The pump cannot
build up pressure.
The lifting station is undersized.
10.4 The pump(s) is/are starting/stopping too frequently even if there is no inflow
Cause
The level sensor fails. The sensor gives wrong signal. •
10.5 One pump starts sometimes without visible reason
Cause
Test run 24 hours after last operation.
Remedy
•
Switch on the level controller or wait until the power
cut is over. During the power cut, drain the collecting
tank with the diaphragm pump.
•
Press the ON-OFF-AUTO selector into position
ON or AUTO.
•
Check and eliminate the cause.
•
Replace the control circuit fuses.
•
Check motor and supply cables.
•
Replace the cable or retighten connections, if
necessary.
Remedy
•
Open all outlet isolating valves.
•
Remove the blockage.
•
Check that the vent hose is correctly fitted between
the vent flange and the tank.
•
Remove any blockage from the vent hole at the
outlet port.
•
Recalculate the inflow parameters and compare the
result with the tank volume and pump performance.
•
If you need a new product, contact Grundfos.
Remedy
Check for air leakages between the level controller
and the sensor tube on the collecting tank.
Remedy
•
No action necessary. It is a safety function that
prevents the shaft sealing from seizing up.
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