Herz pelletfire, Operating Instructions Manual

Page: 16 / 96

9 Operating conditions
16 Betriebsanleitung_pelletfire_Touch_Englisch_V1.2
9.2 Operating conditions with
pellet
9.2.1 Heating off
In this condition the equipment is switched off, i.e.
the burner is blocked.
9.2.2 Ready
The boiler or buffer temperature is sufficient to
sustain the loads or the boiler temperature has
reached the switch-off temperature.
9.2.3 Prepare ignition
In this condition the grate has been cleaned and
the lambda probe pre-heated.
9.2.4 Pre-ventilate
This condition serves to flush the combustion
chamber and the chimney with air.
9.2.5 Cold start
If the boiler room temperature is below the boiler
room ignition identifying temperature (standard
150 °C), a cold start is carried out. Materials are
pushed in at intervals. At the same time the
material is ignited by the ignition fans. During the
ignition phase there is a check as to whether the
ignition was successful.
After successful ignition, the equipment changes
over to the burning phase. At the same time the
final ignition fan phase is carried out. During the
final ignition fan phase the ventilator of the ignition
fans runs for a minute longer in order to cool down
the heating element.
Should there be no ignition in the maximum
ignition period (3 x the set time) then the
equipment is switched off using the remote status
signal => F: IGNITION (see Error 66)
9.2.6 Scorch phase
This phase serves to achieve an even fire bed.
The length of the phase is set in the fuel values
(only in the service area available). Care should
be taken here that combustion takes place with a
higher surplus of oxygen. This serves to achieve
the desired even fire bed more quickly. This
phase should not be set for longer than 5 minutes.
9.2.7 Run up phase
In the run up phase the equipment runs at rated
output. When the boiler temperature is reached it
then goes over to the control phase.
9.2.8 Control phase
In this phase the boiler is modulated between
nominal load and partial load. When the partial
load stage generates too much energy, i.e. the
target boiler temperature + regulation hysteresis
are exceeded and are then changed to the ready
condition.
9.2.9 Burn out phase
When the boiler switches off, then the fuel
remaining in the combustion chamber is burnt out.
Care should be taken here that this time is set
exactly, as otherwise it is possible that material
present in the combustion chamber will not be
burnt correctly.
9.2.10 Burner cleaning
During burner cleaning the burner is cleaned of
ash. Firstly the fuel is burnt out. When the burnout
time is completed, then the burner plate is
cleaned. After successful cleaning the equipment
goes back into normal mode. The interval is
calculated via the runtime of the plug-in screw.
This can be set via the “Cleaning interval”
parameter in the service area, i.e. in order to
achieve more frequent cleaning of the combustion
chamber the parameter simply has to be
shortened.
9.2.11 Heatexchanger cleaning
Heat exchanger cleaning serves to increase the
degree of efficiency. Here the heat exchanger is
automatically cleaned and the fly ash falls into the
so-called fly ash chamber. The interval and
duration of the cleaning can be set in the service
area via the “HEC INTERVAL” or “HEC
DURATION.
9.2.12 Output control
The output control is controlled within the boiler
target temperature and the control end phase.
The control end phase is the boiler target
temperature + control hysteresis. When the
control end phase is reached the equipment goes
to burnout.
9.2.13 Flue gas temperature control
When the maximum flue gas temperature is
exceeded, then the output of the equipment is
reduced. If the temperature is not reached the
equipment goes back to normal output control.
9.2.14 Flame monitoring
Where the combustion values fluctuate too greatly
during operation, this is detected and the
equipment is switched off.
9.2.15 Frost protection
When the equipment goes into frost protection
then the return flow bypass pump is switched on
provided that the equipment is in “HEATING OFF”
or “BURNER STOP” condition. Otherwise the
equipment is started up and started up to a
minimum temperature of 65°C
9.2.16 Lambda control
The amount of material and the suction ventilator
are controlled via the lambda control. This serves
to optimise the combustion and can detect slight
fuel fluctuations. Therefore, it is not necessary to
re-set the combustion after the silo is filled.