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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
Electrical circuit.
Domestic hot water phase.
Operation.
e domestic hot water phase is enabled when the main selector
switch (R10) is on “SUMMER” or “WINTER”.
By running off some domestic hot water, the contact of the
d.h.w. flow switch (S4) closes and, if the temperature measured
by the d.h.w. NTC probe (B2) is less than the temperature
set on the control panel
(or on the CAR if mounted)
, the inte-
grated board powers the boiler circulator (M1) by means of
relay K3 and, by deviating the contact of relay K1, powers the
motor (M) of the 3-way diverter valve (M30) that continues
working until limit switch “3” opens when the d.h.w. position
is reached.
In the meantime, if the flue pressure switch (S6) contact is
idle, “NC”, the adjustment circuit powers the fan (M20) by
means of relay K4.
If the contact of the system pressure switch (S5) is closed
(the
pressure measured in the primary circuit is higher than the
mini-
mum value)
, with the enable of the safety thermostat (E4) and
consequent switching over of the flue pressure switch to “NO”
(S6), the board closes the contact of the request relay K2, so
the ignition cycle can be started, first controlling the ignition
electrode (E1) and then both gas valve coils (Y1).
Burner ignition is detected by the integrated board by way of
the ionisation electrode (E2).
LOW
VOLTAGE
HIGH
VOLTAGE
RELAY BOARD
SUPPLY
RELAY BOARD
CONTROL
CONTROLS-LOGIC MICROPROCESSOR
ZONE CONTROL UNIT
central heating
d.h.w
.
