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44
AST 14 C 255/00
Ventilatore di combustione
ON/OFF
Elettrovalvola
Pressostato aria
Termostato fumi
Accensione
Rilevazione
Blocco
Tempo verifica pressostato aria
o termostato fumi
TW tempo di attesa
Accensione
del bruciatore
Bruciatore acceso
funzionamento normale
Tempo di sicurezza Ts
Blocco
Funzioni
Tempi
AUTOMATIC FLAME CONTROL
The device is always enabled and constantly performs self-check functions.
Upon an operation request, the fan is supplied with power after checking that the air
pressure switch (C type) is in rest condition. As soon as the air pressure switch enabling is
output, the flame control device starts measuring the waiting time TW (1.5 seconds); after
such time, gas valve and igniter will be energised for a maximum safety time TS (10
seconds). If a flame is detected within such time, the gas valve is kept open (energised)
and the igniter is cut-out.
Hereinafter is boiler operation logical diagram:
In case no flame is detected during an ignition attempt, the automatic flame control will
repeat the ignition sequence, performing up to 5 ignition attempts, with a 10-second
ventilation cycle to flush the chamber after each attempt.
In case of flame detection, even if just for a moment, only one ignition attempt will be
performed.
The flame control shut-down will be activated if no flame is detected within the TS safety
time since the last ignition attempt, or if a parasitic flame (while the gas valve is not
energised) is detected for over one minute.
After 5 seconds, reset the shut-down status by pressing the “reset” key on the boiler board
or on the remote control.
WARNING: maximum 5 reset attempts are allowed, both from remote control and from the
boiler interface. After such attempts, the error E98 or E99 will be displayed (no more shut-
down-reset attempts allowed).
Alarm counting is reset each time the board detects a flame or its power supply is
interrupted.
