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Installation and operating instructions Wilo-MVIS 15, 30, 50
7
8.4 Confirm correct rotation
Prior to turning the pump on ensure the rotating
assembly is free of any binding.
•
A red reverse rotation troubleshooting light in the
terminal box
( see figure 1,item 9) lights when the
direction of rotation is incorrect.
• If the red light is on this is due to reverse rotation.
After insuring the main power supply is off, inter-
change two or three leads to reverse the rotation -
the red light should not appear after the rotation has
been corrected and the power has been turned on.
9 Maintenance / Service
All servicing should be performed by an authorized
service representative!
• These pumps are maintenance free. Self-lubricated
by the system fluid, these pumps have no seals to
leak or coupling to break.
• Always keep the pump perfectly clean.
• It is best not to empty the pump for a prolonged
shutdown if there is no risk of frost. If the place of
installation is not protected from frost, the pumps
and pipes must be emptied for the winter:
- Close the isolation valves, open the discharge
screws at the base of the pump (see Fig. 3, item 6)
and the air bleed screw (see Fig. 3, item 5). You must
absolutely close the isolation valves before opening
the screws.
WARNING! Electrical shock hazard
Dangers caused by electrical energy must be
excluded.
Do not attempt the following unless 100% sure
power is off.
WARNING! Risk of scalding
Under some pump or installation operating condi-
tions (temperature of pumped liquid, volume
flow), the whole pump, including the motor, may
become very hot. There is a real risk of burns just
from touching the pump.
WARNING! Electrical shock hazard
Dangers caused by electrical energy must be
excluded.
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.
