CAUTION! Risk of material damage!
If for maintenance or repair work the motor head is detached from the pump
housing, the O-ring located between the motor head and pump housing must
be replaced with a new one. Care must be taken to position the O-ring cor-
rectly when installing the motor head.
• To release the motor, undo the 4 internal hexagon head screws.
CAUTION! Risk of material damage!
Do not damage the O-ring located between the motor head and the pump
housing. The O-ring must lie in the angled end of the bearing plate that faces
the impeller, and must not be twisted.
• After the installation, tighten the 4 internal hexagon head screws again
crosswise.
• For the commissioning of the pump, see section 8.
10 Faults, causes and remedies
Have faults remedied by qualified personnel only!
Observe the safety instructions in section 9!
Fault
The system is making
noises.
Pump is making
noises.
The pump power is too
low.
Installation and operating instructions Wilo-TOP-Z
Cause
Air in the system.
The flow rate at the pump
is too high.
The pump delivery head is
too high.
Cavitation due to insuffi-
cient inlet pressure.
Foreign bodies in the
pump housing or impeller.
Air within the pump.
The shut-off devices in
the system are not fully
open.
Foreign bodies in the
pump housing or impeller.
Incorrect flow direction.
The shut-off devices in
the system are not fully
open.
Remedies
Vent the system.
Reduce the pump power by
switching to a lower speed.
Reduce the pump power by
switching to a lower speed.
Check pressure stability / supply
pressure and, if necessary, increase
them within the permissible range.
After dismantling the motor impel-
ler unit, remove the foreign body.
Vent the pump/system.
Fully open the shut-off devices.
After dismantling the motor impel-
ler unit, remove the foreign body.
Interchange the pressure side and
suction side of the pump. Refer to
the direction of flow symbol on the
pump housing or pump flange.
Fully open the shut-off devices.
English
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