Immergas VICTRIX 75 - Printed Circuit Board (PCB); PCB Layout and Functions; Boiler Operation Modes

23
STV75 ed 01/08 VICTRIX 75
P.C.B.
Inside the boiler’s panel there is an electronic microprocessor
board that controls the appliance’s electrical devices which,
by varying fan speed, permit linear modulation of burner
output.
A “BOARD DISPLAY” is connected to the boiler board that,
by means of a display, indicates boiler operating status and, by
means of keys, it can be RESET and its operating values can
be set, modied and stored.
e integrated board is powered with the main switch (S1)
in "ON" position.
Operation.
Central heating request with a room thermostat.
When the main switch (S1) is ON it powers the integrated
board, the fan (M20) and enables operation in the central
heating mode.
If the system pressure switch (S5) contact is closed (pressure
detected in the primary circuit higher than the minimum value),
after having obtained the enable from the safety thermostat
(E4) and the ue thermostat (E6) and the room thermostat
contact has closed (S20), the board powers the boiler pump
(M1) by means of relay K1.
In the meantime, the adjustment circuit controls the fan
(M20) speed.
If the temperature measured by the ow NTC probe (B1) is
below the set parameter No. 4 “Central heating ow tempera-
ture”, the board enables the start of the ignition cycle.
During ignition, the fan works at a speed that is given by the
value set with parameter No. 28 - between maximum and
minimum.
When the ame is detected, fan speed goes to minimum or
to the value set with parameter No. 29 for a variable period of
time settable in seconds with parameter No. 30 "Stabilisation
time"; subsequently the speed is varied (modulated) directly
proportionate to the dierence between the value set with
parameter No. 4 “Central heating ow temperature” and the
temperature measured by the ow NTC probe (B1).
When the central heating set-point is reached the burner is
turned o and the post-ventilation function is activated for
30 seconds after which the central heating post-circulation
function is activated for a time that can be set with parameter
No. 32.
Re-ignition of the burner for the same request is inhibited for
a time that can be set with parameter No. 40.
Central heating request with thermoregulation.
Utilising the zones and cascade regulator, the operating request
is controlled by the regulator itself which, depending on the
settings, interacts with the boiler’s integrated board by means
of the BUS cables.
Fuse F1
Fuse
F2
BOARD DISPLAY
Technical Documentation
Technical Documentation