10. Troubleshooting
The maintenance and repair operations must be performed by qualified personnel.
Before sevicing the set, disconnect the power supply and make sure there is no pressure in the
hydraulic components.
Problem
1. Set is off
2. Motor does not start
3. Frequent start-ups
and stops
4. The moor starts up
but it stops immedia-
tely
5. The motor runs but
no water is delivred
6. Pump leaks water
7. Too noisy
11.Disposal
Proceed in compliance with local codes an regulations pertaining to disposal of waste, including packa-
ging materials.
Cause
1. Power supply disconnected
2. Blown fuse
1. Powe supply disconnected
2. Triggering of motor protector
3. Single-phase: motor thermal pro-
tector
4. Three-phase: automatic switch in
electric panel
5. Defective motor
1. Defective tank
2. Incorrect adjustment of pressure
switch or sensor thresholds
1. Incorrect tank precharge pressure
2. Incorrect adjustment of pressure
switch or sensor thresholds
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 mehanical stress on pump
1. Water return when pumps stop
2. Cavitation
3. Pump rotation hindered
Solution
Connect power supply
Replace fuse
Connect power supply
Eliminate malfunction.
Single-phase: wait for automatic reset
Three-phase: Reset the atomatic
switch
Repair/replace motor
Repair/replace tank
Increase the differential pressure or
the stop pressure
Check tank precharge
Increase the differential pressure or
the stop pressure
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
en
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