Cleaning Prior To Start; Filling And Venting; Starting The Pump - Wilo -SCP Installation And Operating Instructions Manual

8.1.2 Cleaning of bearings
SCP pumps are fitted with pre-lubricated, sealed bearings which
do not require external lubrication for life. For Ball bearings which
require external greasing (Ref. table Pg. 30&31) and if the unit
has been in store for a long period before commissioning, the
bearings should be cleaned and flushed out with clean white
spirit or good quality paraffin. Waste oil/paraffin & used cotton
cloth should not be used for this purpose, as particles of foreign
matter may be left behind which would cause damage when the
bearing is in service. Bearings should be then filled with
recommended grade and quality of fresh lubricant to the level.
Refer list of lubricants at the end of this manual.

8.2 Filling and venting

Fill and vent the system correctly, through air cock. Brief dry
running will damage the pump. Please also note that these
pumps are not self-priming, which means that the impeller &
casing must always be fully filled with fluid to be handled before
putting in operation.
WARNING! Danger of injury!
There is a risk of burns if the pump is touched! The entire pump may
become very hot, depending on the operating state of the pump or
system (fluid temperature).
CAUTION! Danger sealing system damage!
Any attempt to run the pump dry or partially full may result in seizure
of the rotating internal components.
8.2.1 Pumps operating on flooded suction head
When these pumps operate on a flooded suction head open the
air release valve situated on top of the pump casing, open the
pump inlet isolating valve and vent the air out of the casing.
When the liquid issues from the air vent, free of air, the pump is
properly primed. The air vent must be closed after priming and
before the pumping set is started.
Installation and operating instructions WILO-Split Case Pumps
8.2.2 Pumps operating on negative suction head
There are two methods of priming pumps that draw their
liquid from an elevation lower than the pump inlet
branch:
• If the inlet pipe work is fitted with a non-return foot valve,
the pump casing and inlet pipe work can be filled with
liquid from an external source under pressure. The pressure
imposed on the pump by this method must not exceed
that for which the pump is designed. In certain cases
priming can be achieved by flooding back from the delivery
side of the pump.
• By extracting air or gas from the pump casing. To enable
this method to be used, the gland arrangement must be
sufficiently airtight or it should be liquid sealed from an
external supply. For operation details of gas exhausts
reference should be made to the manufacturer's
instructions. Some form of priming indicator is usually
fitted to indicate when the priming operation is complete.
8.2.3 Pumps operating on hot liquids
Pumps operating on hot liquids are usually so arranged
that the liquid flow into the pump is under pressure. If the
saturation pressure of such liquids is above atmospheric
pressure, any attempt to prime the pump will result in the
liquid "flashing" from the air cocks. For these reasons, the
air cocks at the top of the pump casing should be left
slightly open when priming boiler circulating pumps until
air has been driven out of the casing completely.
The cooling water services of a pump handling hot liquids
should be turned on before the pump is primed. These
services may supply cooling water to the bearings and / or
stuffing boxes. Where the services are functioning, open
the inlet valves and start warming the pump throughout.
Never cut off the water services while the pump is "on
temperature". Where bearings are water cooled, adjust
the cooling water supply until the bearings have a running
heat. Over-cooling may lead to condensation of moisture
from the atmosphere inside the bearing with consequent
contamination of the oil. The suction valve, if provided,
must be fully open and the delivery valve must be closed.

8.3 Starting the pump

8.3.1 Direction of rotation
Disconnect the drive coupling and run the motor to check
its direction of rotation. A directional arrow is provided on
the pump unit.
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