7.3.4 Variable Ignition
Time : 4 minutes (TIMER t02)
This stage starts the ignition process.
The heat from the ignition element is directed at the pellets by the
combustion fan which runs at a relatively slow speed.
At intervals the auger introduces more pellets once the flame has begun
to establish.
The photocell monitors the light level as the flame develops.
The flue gas temperature probe measures the temperature in the flue.
At the end of this stage the photocell checks to make sure the flame
intensity is over a pre-defined level and the flue gas temperature is over a
pre-defined temperature. If both of these variable are satisfied then the
process continues to the next stage (Stabilisation)
If these variables are not satisfied then this stage continues for another 3
minutes (second ignition attempt) and if the variables have not reached
their values by the end of the second attempt, EXTINGUISHING will occur
and an Er12 (Failed Ignition) will be displayed on the screen).
7.3.5 Stabilisation
Time : 60 seconds (TIMER t03)
This stage develops the flame even further before allowing the system to enter RUN
mode.
The auger introduces pellets more frequently into the burner.
The combustion fan and exhaust fan increase in speed to speed up the
combustion process.
The ignition element remains on in this stage.
At the end of this stage the photocell checks to make sure the flame
intensity is over a pre-defined level and the flue gas temperature is over a
pre-defined temperature. If both of these variable are satisfied then the
process continues to the next stage. (Run mode)
If these variables are not satisfied then this stage continues for another 3
minutes (second ignition attempt) and if the variables have not reached
their values by the end of the second attempt, EXTINGUISHING will occur
and an Er12 (Failed Ignition) will be displayed on the screen.
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