Troubleshooting - Lowara GEM Instrucciones Para La Instalación Y El Uso

10

TROUBLESHOOTING

A few troubleshooting operations can be performed directly by the user, while others must be carried out by a qualified
maintenance technician.
Important: before carrying out any of these operations, refer to the relative section on putting the electric
pump in safe mode.
Fault
1. Set is off
2. Motor does not start
3. The motor runs but
no water is delivered
4. Pump leaks water
5. Too noisy
6. The pump does not
prime
7. The stop button does
not stop the pump
8. The unit does not
provide the required
level of performance.
Cause
1. Power supply disconnected
2. Fuse blown
1. Power supply disconnected
2. Fuse blown
3. Panel automatic switch
4. Defective motor
1. No water on suction side or inside
pump
2. Air in suction piping or pump
3. Loss of pressure on suction side
4. Check valve jammed
5. Clogged pipe
6. Incorrect rotation of three-phase motors
1. Defective mechanical seal
2. Undue mechanical stress on pump
1. Water return when pumps stop
2. Cavitation
3. Pump rotation hindered
1. Suction piping of insufficient width;
excessive use of fittings that cause
sudden changes in direction of the
suction piping; siphon effect
2. Clogged suction piping
3. Air leaking into the suction line of the
pump
4. Base valve clogged or blocked
5. On-off valve on suction line partially
closed
1. Considerable loss of water in the system
meaning the pressure cannot reach the
level required to open the pressure switch
(about 1.5 bar above the closing pressure
of the pressure switch, i.e. the starting
pressure of the electric and diesel pump)
2. A jumper has been used for the
terminals to connect the float in the
priming tank (installed in the case of a
suction lift installation)
1. Use of a unit of insufficient size in
relation to the nature of the system.
2. Excessive consumption of water in
relation to the amount supplied by
the water source (tank, well,
aqueduct, etc.)
3. Motors turn in the wrong direction
4. One or more pumps are clogged
5. Clogged pipes.
6. Base valves clogged or blocked
(suction lift installation)
7. On-off valves on suction and delivery
lines partially closed.
8. Leaking of air in the inlet pipes of the
pumps of the unit.
Solution
Connect the power supply
Replace the fuse
Connect the power supply
Replace the fuse
Reset the automatic switch
Repair/replace motor
Fill the pump or suction piping / open the on-off valves
Bleed the pump, check the suction connections
Check the NPSH and, if necessary, modify the system
Clean the valve
Clean the pipe
Change direction of rotation
Replace the mechanical seal
Support the pipes
Check the check valve
Check suction
Check for undue mechanical stress on pump
Check correct layout and installation of the suction
piping with reference to the section on "Installation.
Clean or replace it.
Carry out a pressure test to check the airtightness of
the fittings, joints and pipes.
Clean or replace it.
Open it fully.
Check the seals, fittings and pipes.
Remove the bridge in the case of a positive suction
head installation. Insert the float for the priming tank in
the case of a suction lift installation.
Replace it with one that meets
the requirements.
Increase the amount supplied by the
water source.
Change this with reference to the section on "Start-up".
Disassemble these and clean the body of the pump and
the impellers,
checking that these are in good condition.
Clean or replace them.
Clean or replace them.
Open these fully.
Carry out a pressure test to check the airtightness of
the fittings, joints and pipes.
74