Wilo Wilo-Star-AC Series, Installation And Operating Instructions Manual

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17
ENGLISH
temperature) the pump/mo-
tor can become very hot.
– Close the valve on the discharge
side.
Risk of scalding!
Depending on the fluid
temperature and the sys-
tem pressure, if the vent
screw is completely loose-
ned hot liquid or vapour
can escape or even shoot
out at high pressure.
– Carefully loosen and fully remove
the vent plug with a suitable scr-
ewdriver (Fig. 9).
– Carefully push pump shaft back
several times with screwdriver.
– Protect all electrical parts against
the leaking water.
– Switch-on pump.
It is possible that the
pump blocks with the
vent plug open, de-
pending on the sys-
tem pressure.
– After 15...30 s tighten the vent
plug.
– Re-open isolating valve,
Speed setting
If the rooms cannot be sufficiently
heated, the speed of the pump may
be too low. In this case you will
need to switch to a higher speed.
If, on the other hand, the pump is
set at too high a speed, flow noise
may occur in the lines and in parti-
cular at throttled thermostatic val-
ves. This can be rectified by swit-
ching to a lower speed.
The speed is changed by means of
a rotary button at the terminal box.
3 represents the lowest and 1 the
highest speed.
7 Maintenance
Prior maintenance or repair
work switch off the pump
and secure against unaut-
horized switching.
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 depo-
sits 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
ATTENTION!