Strebel Biotec 25, Инструкция пользователя

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Operational phases
Ignition phase
If the flue gas temperature is above the temperature requir-
ing auto ignition of the pellets, the controller knows that the
combustion chamber holds enough ember temperature to
successfully continue combustion. In this case the ignition
device is not required . The dosage of pellets continues.
If the flue gas temperature shows the temperature to be low
the controller knows that the combustion chamber has not
enough ember temperature to successfully continue combus-
tion.
First the fan is switched on to purge the combustion chamber
and vents before the ignition device is energised.
Second the pellet auger pushes enough pellets for light up
into the combustion chamber.
Third the ignition device is switched on
The Boiler now enters the warm up phase of operation.
Warm-up phase
The ignition device is switched off and the dosage of pellets is
reduced. The fan runs with increased speed (according to the
setting). in comparison to the combustion phase. The warm-
up phase has the purpose to “fan the fire” and let it spread
across the pellets in the combustion chamber. The duration of
the warm-up phase is fairly short. After this phase, the normal
run combustion phase starts.
In the case that the flue gas temperature does not rise be-
yond a pre programmed set temperature the controller rec-
ognises that the pellets can not be burning and the boiler
stops operation. The display shows “FAILED IGNITION“.
Combustion phase
During combustion phase, the pellet and air supply are regu-
lated based on the parameter settings. The controller aims for
the boiler to increase the temperature up to the „Maximum
boiler temperature“. when this is reached the boiler slowly
reduces its output to prevent repeated turning off and on .
The boiler shifts to pause mode when the temperature reach-
es the „Maximum boiler temperature“. On the top row the
display shows „Rated temp reached“. The boiler re starts op-
eration when the temperature of the boiler flow drops below
the set parameter “Maximum boiler temperature“. The de-
tected flue gas temperature determines if the boiler opera-
tion starts with the warm-up phase or the ignition phase as
described above
If a room thermostat or on off control (if used ) switches off,
it activates the setting that turns off the boiler and therefore
it sends the boiler into a phase of
after-run., the boiler will
then quickly reach the required temperature and operation
will stop.
The pump will start if the boiler temperature rises beyond
the required temperature and also if the room thermostat
demands heat.
If the room thermostat /control does not call for heat the
pump runs for a period of 5 minutes after the boiler has
switched off then the pump stops until the room thermo-
stat/control calls for heat again.
OPERATIONAL PHASES
Programming the Control
Programming the Control should be carried out before
lighting the Boiler. Follow the logical steps shown on the
next pages.
The Boiler Commissioning must be carried out by a
trained engineer with the necessary approvals