EN
Function
General safety functions
Description of functions
When the system is switched on for the
first time, after a power failure or safety
shutdown, after a lack of gas or after the
system has been out of operation for 24
hours, the pre-ventilation period of 30
seconds begins.
During prepurge period:
- blower pressure is monitored
- the combustion chamber is monitored for
flame signals.
At the end of the prepurge period:
- ignition is switched on.
- main and safety valve are opened.
- burner starts.
Monitoring
The flame is monitored by an ionization
probe. The probe is insulated and
1
108
143
F4
Minimum gas pressure switch
F6
Air pressure switch
Y13
Solenoid valve
Y12
Solenoid valve
1
Thermally-triggered safety shut-off valve (installation resident).
104
Gas pressure regulator
106
Filter
108
Gas ball valve (installation resident)
119pBr Measuring point for gas outlet pressure.
143
Antivibration coupling (installation resident).
8
fitted to the gas head and is routed
through the flame disc into the flame
zone. The probe must not have any
electrical contact with earthed parts.
The burner switches to lock-out if a short
circuit occurs between the probe and
the burner earth.
During burner operation, an ionised
zone is produced in the gas flame
through which a rectified current flows
from the probe to the burner
Safety functions
- If no flame is produced when the burner
is started (gas release), the burner will be
switched off at the end of the safety
period, and the gas valve will close.
- If the flame goes out during operation,
the gas supply is interrupted and the
control unit goes to block.
- If there is a lack of air during reventilation
or operation, the control unit goes to
block.
- If there is a lack of gas, the burner does
not begin operation or switches off.
106
F4
Y12
104
head.
Y13
119 pBr
In the event of controller shutdown
- Controller thermostat interrupts heat
request.
- Gas solenoid valves close.
- Flame goes out.
- Burner motor switches off.
- Burner is ready for operation.
F6
420010605300