Starting And Checking Operations; Switch Off Of The Pump - FLOWTECH flowboost F.V Operation And Maintenance Manual

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When the liquid level on the suction side is above the pump (inflow under positive suction head, fig. 3B),
fill the pump by slowly and completely opening the inflow gate valve while keeping the delivery gate valve and
air vent holes open to release the air.
During filling, keep the air vent holes open only if the inflowing liquid presents no possible danger on account
of its nature, temperature or pressure.
Only for 50-65-80, if necessary, install joints with a tap/valve device to holes 1 and 2, to control the outflow of
the liquid and its direction of flow.
With a delivery pipe arranged horizontally, or lower than the pump, keep the delivery gate valve closed during
the filling operation.

Starting and checking operations

Close the air vent holes (fig.4), 25-32-40 Tighten the needle screw in the drainage plug (fig. 4b) and close
the air vent hole. Start the pump with the delivery gate valve closed and with the suction gate valve fully open.
Immediately afterwards, gradually open the delivery gate valve, adjusting the point of operation within the
limits indicated on the name plate.
When starting, with a three-phase motor, check if the direction of rotation is as shown by the arrows on the
lantern bracket. Otherwise disconnect electrical power and reverse the connections of two phases.
Check that the pump works within its field of performance and that the absorbed current shown on the
name-plate is not exceeded. Otherwise adjust the delivery gate valve or the setting of any pressure switches.
If a priming loss occurs (interruption of delivery flow, despite opened gate valves) or if a pressure oscillation
is indicated on the pressure gauge, repeat the venting operation on the suction side (2), make sure all the
suction pipe couplings are perfectly sealed and tighten the air vent plug (2) and the draining plugs (3) on the
suction side (fig.4).
ATTENTION: when the pump is located above the water level (suction lift operation, fig. 3A), after a long idle
period, before restarting the unit, check that the pump is still filled with liquid and vented. Otherwise, check for
proper operation (opening and closing) of the foot valve and fill the pump with liquid.
Never run the pump for more than five minutes with a closed gate valve. Prolonged operation without a
change of water in the pump causes dangerous increases of temperature and pressure. In systems in which
it may be possible to operate with a closed delivery gate valve, install a bypass valve (fig. 3) to ensure a
minimum flow.
When the water is overheated due to prolonged operation with a closed port, stop the pump before opening
the gate valve.
To avoid any risk of danger to users and the creation of harmful thermal stress in the pump and system due
to large temperature differentials, wait until the water has cooled inside the pump before starting again or
before opening the drainage and filling plugs.
Care must be taken when the pumped fluid has a high temperature. Do not touch the fluid when its
temperature is higher than 60 ˚C.
Do not touch the pump or motor when their surface temperature is higher than 80 ˚C.

Switch off of the pump

The appliance must be switched off every time there are faults. (See troubleshooting).
The product is designed for a continuous duty, the switch off is performed by disconnecting the power
supply by means the expected disconnecting devices. (See Electrical connection).