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STEEkW ed 12/03 EOLO Eco kW
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STEEkW ed 12/03 EOLO Eco kW
Technical Documentation
Technical Documentation
Technical Documentation
Technical Documentation
Loads.
e board is always powered, regardless of the position of the main selector switch (R10)
(see integrated board operation).
Integrated board
It is powered by the integrated board following a d.h.w., central heating or antifreeze
request.
It permits water circulation in the primary circuit.
Boiler circulator
(M1)
It is powered at mains voltage by the integrated board when burner ignition is neces-
sary.
It allows passage of gas to the burner.
Gas valve (Y1)
(main coils)
It is controlled by the integrated board’s ignition circuit that produces an electric discharge
between its end and the earthed electrode
(dummy).
Upon contact the air-gas mixture ignites.
Ignition electrode
(E1)
is ensures the flow of air inside the sealed chamber and the extraction of flue produced
by combustion.
It is powered by the integrated board.
Fan
(M20)
Low voltage circuit.
It permits operation of the boiler with 3 zone valves or external
pumps controlled by the relevant room thermostats.
Zone 1 is controlled
(times and temperatures)
by the CAR
.
Zone control unit (CZ)
(external optional)
It permits the remote control of the generator
(SUMMER/WINTER
switch, temperature setting and indication, alarms display, reset, etc.)
and acts as a weekly timer-thermostat.
Remote Control
(CAR)
(optional)
See Remote Con-
trol operation
(CAR)
See zone control
unit operation
After running domestic hot water, it acts on the integrated board
that starts the d.h.w. phase.
When idle it enables operation in the central heating phase.
D.h.w. flow switch
(S4)
Interrupted
contact
It diverts the primary circuit water flow from the central heating system to the d.h.w. plate
exchanger and vice versa.
It is powered by the integrated board.
3-way diverter valve
(M30)
Safety devices and controls.
When the pressure in the boiler circuit is less than 0.3 bar it turns
the burner out.
System pressure switch
(S5)
Interrupted
contact
It is a clock that acts on a switch (
see the low voltage circuit controls and safety devices)
enabling
or preventing boiler operation in the central heating phase during preset time intervals.
If the timer is connected it is always powered regardless of the position of the main selec-
tor switch (R10).
Central heating timer (P1)
(External optional)
