Faults, Causes And Remedies - Wilo -Zeox FIRST Installation And Operating Instructions Manual

10 Faults, causes and remedies

WARNING! Electrical shock hazard!
Danger from electrical current must be eliminated.
• All electrical work must be performed after the electrical supply has been switched off
and secured against unauthorized switching.
WARNING! Risk of scalding!
At high water temperatures and system pressure close isolating valves before and
after the pump.
First, allow pump to cool down.
Blocked pump
Pump does not prime
Insufficient capacity
Insufficient pressure
Installation and operating instructions Wilo-Zeox FIRST
• Moving parts rusted due to
longstop period.
• Foreign matter inside the pump.
• Partial priming due to air inside
the pump or suction pipes.
• Defective or clogged foot-valve
which cannot close and that
does not allow pipe and pump
filling.
• Air leaks in the suction pipe.
• Excessive suction head (NPSH
too low).
• Wrong rotation direction.
• Clogged or badly functioning
foot valve.
• Inadequately dimensioned suc-
tion pipe or foot valve.
• Impeller worn or clogged.
• Impeller wear rings are worn.
• Excessive suction head (NPSH
too low).
• Water contains gas.
• Suction pipe with curve
upwards where air collects.
• Air leaks in the suction pipe.
• Check, repair or replace.
• Check, remove the obstruction.
• Remove air in the pump through
the breather holes.
• Clean or replace the foot valve.
• Locate air passage and stop it.
• Reset head of dynamic level,
reduce capacity or replace the
pump with a suitable model.
• Exchange two of the three
phases.
• Disassemble, clean or replace.
• Disassemble and replace with a
more suitable pipe.
• Disassemble, clean or replace.
• Disassemble the electric pump
and repair. Caution! Follow
instructions foreseen in the
warranty conditions.
• Reset head of dynamic level,
reduce capacity or replace the
pump with suitable model.
• Call WILO Customer Service.
• Eliminate critical point respect-
ing the requested inclination to
the suction pipe.
• Locate air passage and stop it.
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