Flotec EVOTRONIC 350 Betriebsanleitung Seite 21

To avoid the need to drain the system
in the event of pump maintenance, the
installation of a shutoff valve is recom-
mended, on the suction and delivery pipe-
lines.
If the pump remains in operation
with the delivery valve closed for
more than a few seconds, the liq-
uid will overheat. Never use the pump
with the shutoff valve closed on the deliv-
ery side.
The pump should be installed in such
a way to avoid the risk of air pockets in
the body or pipelines, in particular on the
suction side of the pump.
Pipelines and valves must be correctly
sized according to the installation.
Pipelines must not cause excessive me-
chanical stress on pump suction or de-
livery with excessive loads and torque
values.
If flexible hoses are used, fit a semi-rigid
pipe on suction to avoid the risk of shrink-
age due to negative pressure on suction.
It is recommended to fit a filter on the in-
let of the suction pipeline where the pump
is used for pumping water from a well or
tank used for the recovery of rain water.
Periodically check the condition
of the filter and regularly clean
or replace this element.
The pump is installed with positive suc-
tion head when it is located below the liq-
uid in suction. Figure 1
1. Shutoff valve
2. Filler cap
3. Check valve
4. Expansion tank
The pump is installed with negative suc-
tion head when it is located above the liq-
uid to be received. Figure 2
1. Shutoff valve
2. Filler cap
3.
4. Expansion tank
5. Foot valve
Correct pump installation is essential to
ensure priming.
• Position the pump in the vicinity of
the well or tank to ensure that the
suction pipe is as short as possible. In
this way, the priming time is reduced,
above all in the case of large differ-
ences in height between the liquid and
suction point.
• Use a pipeline that is at least the
same diameter as that of the pump
suction port.
• To avoid the formation of air vortexes,
immerse the suction pipe by at least
0.5m in the liquid to be pumped (Fig-
ure 2, H1>=0.5m);
• Install a foot valve with filter at the
end of the suction pipe ( Figure 2)
• Ensure complete sealing of the suc-
tion pipe;
• Use wide bends on the suction sec-
tion;
In the case of self-priming pumps ensure
that the minimum height H3 (between the
center of the suction port and the check
valve or between the center of the suction
port and first point of use) in the table1
are observed to guarantee suction height
H2 (Figure 3).
ENGLISH
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