Wilo SiFire, Installation And Operating Instructions Manual

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English
44 WILO SE 10/2013
10 Faults, causes and remedies
The operations indicated in the table below must
be carried out ONLY by expert personnel. Never
carry out any work without having first carefully
read and understood this manual. Never attempt
to carry out repairs of materials and equipment
without a fully and correctly understanding of this
one.
If people do not have sufficient knowledge about
the product and the operating logic required by
specific standards relatives to fire extinguishing
systems, or if people do not have the technical
skills needed, contact Wilo to make regular main-
tenance checks.
Faults Causes Remedy
The control panel is off. No power supply Make sure that the supply line is con-
nected and voltage is present.
Out-of-order fuses Check and/or replace fuses. Check and/
or replace the control panel.
Auxiliary circuit failing Check voltage of primary and secondary
circuits in the transformer. Check and/or
replace fuses of the transformer.
Motor does not start No power supply Check connections and electric control
panel.
Short-circuit in winding Check windings of motor
Control panel faulty/Wrong connections Check connections
Overload
Check sizing of the supply line. Make
sure that the pump is not blocked.
Pump works, but does not supply water,
or has a low flow/height. Wrong direction of rotation Invert two of the motor supply phases.
Excessive suction depth. Pump in cavita-
tion Review calculations to suit pump NPSHr.
Wrong diameter of the suction pipe and
valves Pump in cavitation Review calculations to suit pump NPSHr.
Air inlet in the suction line Make sure that there are no leaks in the
suction line. Check the distance
between the suction points if several
pumps have been installed. Fit anti-vor-
tex plates.
Valves partially/totally closed Open the suction and discharge valves.
Worn pump Check and repair.
Pump rotor obstructed Check and repair.
Strainer/filters obstructed Check and repair.
Coupling between pump and worn
motor Check and repair.
Motor fails to reach nominal speed or has
vibrations Check speed,
see above
Pump bearings are worn or not oiled Lubricate with lubricators.
Motor fails to reach nominal speed Too low voltage at motor terminals Check power supply voltage, connec-
tions and the cross-section of the cables
in the power line.
False contacts in the power contactor or
problem with the start-up device Check and repair.
Phase failure Check line, connection and fuses.
False contacts in power supply cables
Check terminal fixing.
Winding to the earth or short-circuit Dismantle the motor, repair or change it.
Non-operational pumps once started Incorrect sizing of power line Check and replace.
Insufficient voltage Check power supply.
Pump sizing Remove the rotating parts then check.
Presence of voltage on motor carter Contact between line cables and earth Correct connections.
Humid or old Insulation Wipe motor or re-wind it.
Short-circuit between terminals and
external housing Check insulation between terminals and
carter.