Troubleshooting; The Booster Set Is Off; Motor Does Not Start; Frequent Start-Ups And Stops - Xylem LOWARA SMB /SVE Series Installation, Operation And Maintenance Manual

7 Troubleshooting

Precautions
WARNING:
 Faults must be corrected by a technician possessing the technical-professional requirements
 Observe the safety requirements in the chapters on Use and Operation and Maintenance
 If a fault cannot be corrected or is not mentioned, contact Xylem or the Authorised Distributor.
The frequency converter saves the last alarms that have occurred. Refer to the instructions on
use of the frequency converter for the types of fault and how to check the last alarms that have
occurred.

7.1 The booster set is off

Cause
Power supply cut off
Switch in OFF position

7.2 Motor does not start

Cause
Power supply cut off
The thermal overload protection of
the motor has been triggered
Motor (coil) faulty

7.3 Frequent start-ups and stops

Cause
Diaphragm pressure tank faulty
Incorrect pre-charge of the
diaphragm pressure tank
The pre-charge value of the
diaphragm pressure tank is at zero
7.4 The speed of the pump unit increases and decreases without
stopping and without consumption of water (utility closed)
Cause
Loss of water from the non-return
valve
The diaphragm pressure tank is
damaged or undersized
outlined in the current regulations
Remedy
Restore the power supply
Turn the switch ON
Remedy
Restore the power supply
Eliminate the fault and reset the switch
Check and repair or replace the motor
Remedy
Repair or replace the diaphragm pressure tank
Set the new pressure pre-charge value according to the pump unit and
setpoint
The diaphragm pressure tank must be pre-charged
Remedy
Check the hydraulic system and the valve
Repair or replace the diaphragm pressure tank
en – Original instructions
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