Light Signal Operation Check; Pressure Switch Functionality Test; Emergency Starting Circuit Check; Pressure Switches Settings - Grundfos Hydro EN Installation And Operating Instructions Manual

Diesel pump speed adjustment
The speed of rotation of the motor pump is fixed in the fac-
tory during testing operations; it remains possible to make an
adjustment in the phase of the first start up to be able to better
meet the demands of the plant and for this purpose there are
provided fasteners on accelerator which limit the adjustment
possibilities.
A low rotation speed implies a lower flow of wa-

ter to the heat exchanger and a possible engine
damage due to overheating.
Changing the speed of the motor pump can

compromise the proper functioning of the
pumping unit. The procedure described below
should only be performed by qualified person-
nel.
In the case an adjustment is necessary, proceed as follows:
• leave any electric pumps totally deactivated, cutting off the
voltage to their control panels,
• set the operation selector on MAN on the diesel control
panel,
• close all the discharge gate valves,
• open the suction gate valve,
• open the flow rate test loop,
• start the diesel pump and open the throttling valve down-
stream of the flow meter in order to meet the design duty
point,
• if necessary, change the speed use the diesel engine throttle
than block the accelerator in the position determined.

15.2 Light signal operation check

Press the specific button and all the warning lights will light up,
showing their correct operation.

15.3 Pressure switch functionality test

Two control pressure switches for each duty pump on the
fire-fighting pumping sets are required, as specified in the EN
12845 standard.
The operation of every single pressure switch is then to be
checked regularly, and for this reason the control panels are
equipped with a device that allows the check of the proper
operation for every single pressure switch.
Refer to the paragraphs dedicated to the control panel of the
electric and/or diesel duty pump.

15.4 Emergency starting circuit check

As specified in the EN 12845 standard, two buttons protected
by glass for the emergency starting of the diesel engine are
envisaged on the pumping set; a periodical test must be
executed for checking the operation of these buttons without
breaking the protective glass.
The control panel of the diesel pump has two buttons to test the
functionality of the starting circuit of emergency that become
active only in the following two cases, as prescribed by the
standard (refer to specific paragraph):
• after an automatic engine start followed by a stop,
• after 6 unsuccessful attempts to start.

15.5 Pressure switches settings

All piumping sets are factory setted and tested before shipment
to ensure the optimum performance; can still be the case of
having to make settings changes to better meet the demands of
the system.
Refer to the specific documentation of the pressure that is an
integral part of this manual.

15.6 Timer UNI 10779 settings

See paragraphs dedicated to electric and diesel pump control
panel.
16.

Maintenance

Before starting work on any of the pumps, en-

sure that it cannot be accidentally activated.
The terminals and wires upstream of the panel
mains switch are supplied even if the switch is
in the OFF position. Cut off the voltage by us-
ing the mains general switch and block it in the
OFF position to e sure that it cannot acciden-
tally reactivate.

16.1 Electric pump

Check regularly the alignment of the spacer

coupling based on the operation time of the
pumping set.
For electric pumps the check and replacement (if needed) of
wear parts is normally left to good workmanship practices.

16.2 Diesel pump

Check regularly the alignment of the spacer

coupling based on the operation time of the
pumping set.
For the diesel engine, as for all internal combustion engines,
are scheduled service intervals regular depending, in general,
from the hours of operation of the engine or the time since
commissioning (example: periodic check of engine oil or cooling
liquid).
For all information on diesel engine maintenance, refer to the
specific documentation provided with the pumping set.
Cooling circuit of the diesel engine
Do not open the cap of the heat exchanger

when the motor is running, and in any case not
before you are sure that the heat exchanger is
cold.
The cooling circuit needs periodic checking, the frequency of
which usually depends on the hours of operation, the time that
has elapsed since it has been put into operation, the quality
of the water used for the secondary exchanger circuit (water
coming from the fire fighting network).
Check the water flow in the heat exchanger
Through the pressure gauge upstream of the exchanger, check
that the pressure, during operation of the diesel pump, remains
within the area highlighted on the gauge.
Excessive pressure indicates that there is an obstruction inside
the heat exchanger or on the output of the circuit; check imme-
diately that there are no obstructions in the outlet branch or in
the exchanger.
Coolant level check
Make sure that the motor is off, open the cap of the exchanger
and check the level of coolant inside the water/water heat
exchanger and restore it, if necessary.
Use a mixture of de-mineralised water and antioxidant anti-
freeze fluid (inhibited ethylene glycol type) appropriate for the
purpose.
Avoid contact with eyes and skin, and do now swallow the cool-
ant.
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