Wilo Wilo-Star AC, Installation And Operating Instructions Manual

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ENGLISH
8 Problems, Causes
and Remedies
Motor is switched on but fails to
run:
– Check electrical fuses,
– Check voltage of pump (observe
rating plate data),
– Check capacitor size (observe
rating plate data!).
– Motor is blocked, e.g. by deposits
from the heating water.
– Remedies: Fully remove vent plug,
check and if necessary rectify free
running of pump rotor by turning
the slotted end of the shaft with a
screwdriver (Fig. 9).
At high water temperatures
and system pressure close
isolating valves before and
after the pump. First, allow
pump to cool down
Noisy pump operation
– Cavitation due to insufficient inlet
pressure.
– Remedies: increase system pressu-
re within the permissible range.
– Check speed setting, if necessary
switch to a lower speed.
If the fault cannot be rectified,
contact your nearest WILO
Customer Service.
9 Spare parts
All rating plate data must be stated
when ordering spare parts.
Subject to technical alterations!