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TEMPERATURE PROTECTION
The controller is provided with additional software (digital) tempera-
ture protection against dangerous increase in the temperature. When the
alarm temperature (set within the 80 °C–85 °C range) is exceeded, the
blower fan and the fuel feeder are disconnected. At the same time, active
pumps start to work to distribute heat in the system. When the boiler alarm
temperature is exceeded, the audio alarm is activated and the message
is displayed
"Temperature too high”
. When the temperature returns to
the safe value, the alarm is switched off by pressing the
encoder
, and the
regulator returns to the last set operating mode.
THERMAL PROTECTION
The boiler controller is equipped with the
safe temperature limiter
protecting against boiler overheating (water boiling in the system) when
the controller is damaged. The safe temperature limiter is a protecting
device in form of a bimetallic sensor installed near the boiler water tem-
perature sensor, cutting off power supply to the blower fan and the fuel
feeder when the limit temperature exceeds 90 °C (central heating pump
remains switched on). The equipment cannot be restarted automatically,
even when the temperature is lowered. The user must switch them on, re-
setting the sensor (with the STB button) after the temperature is reduced.
When this sensor is damaged or overheated,
the fan and the feeder are
switched off
(do not work either in the manual or the automated mode).
FUEL TANK SECURITY DEVICES
To ensure safe operation of the boiler, the fuel feeder is equipped with a
security system consisting of several steps.
Components of this system
include a protection against flashback to the fuel tank through the
feeder (a mechanism of two transport screws separated with a trans-
fer duct, a temperature sensor in the fuel route) and additional protec-
tion against overheating – a thermal switch installed in the boiler
. The
fuel from the fuel tank is transported to the furnace chamber in such way
as to eliminate a risk of flashback to the fuel tank during normal operation
or feeder downtime, as well as during power outages or power supply
failure. The mechanism protect against uncontrolled flashback into the
fuel tank without a need to install a water extinguishing system. Safe fuel
transport is ensured by location of loading openings for fuel distribution
pipes and by a distance between these pipes. The screw conveyors are
rotated by gear wheels driven by a chain driven by a gearmotor. For safety
reasons a flap closing the fuel tank during the biomass burning must be
tightly closed.
