FLYGT 3085 - 7.2 The pump does not stop when a level sensor is used; 7.3 The pump starts-stops-starts in rapid sequence

Cause Remedy
The installation is not receiving
voltage.
Check that:
• The main power switch is on.
• There is control voltage to the start equipment.
• The fuses are intact.
• There is voltage in all phases of the supply line.
• All fuses have power and that they are securely fastened to the fuse
holders.
• The overload protection is not tripped.
• The motor cable is not damaged.
The impeller is stuck. Clean:
• The impeller
• The sump in order to prevent the impeller from clogging again.
Always state the serial number of your product, see Product Description (page 10).
7.2 The pump does not stop when a level sensor is used
DANGER: Crush Hazard
Moving parts can entangle or crush. Always disconnect and lock out power before
servicing to prevent unexpected startup. Failure to do so could result in death or serious
injury.
WARNING: Electrical Hazard
The permanent-magnet motor generates voltage when the shaft rotates, even if power
sources are disconnected. Never perform any electrical work if the shaft could rotate.
Cause Remedy
The pump is unable to empty the
sump to the stop level.
Check that:
• There are no leaks from the piping and/or discharge connection.
• The impeller is not clogged.
• The non-return valve(s) are functioning properly.
• The pump has adequate capacity. For information:
Contact the local sales and service representative.
There is a malfunction in the level-
sensing equipment.
• Clean the level regulators.
• Check the functioning of the level regulators.
• Check the contactor and the control circuit.
• Replace all defective items.
The stop level is set too low. Raise the stop level.
Always state the serial number of your product, see Product Description (page 10).
7.3 The pump starts-stops-starts in rapid sequence
Cause Remedy
The pump starts due to back-flow
which fills the sump to the start level
again.
Check that:
• The distance between the start and stop levels is sufficient.
• The non-return valve(s) work(s) properly.
• The length of the discharge pipe between the pump and the first non-
return valve is sufficiently short.
7 Troubleshooting
64 Flygt 3085 Installation, Operation, and Maintenance Manual