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8 SAFETY AND ALARMS
8.1 Safety devices
CAUTION: During operation, some parts of the boiler (door, handle, ceramic parts) may reach very
high temperatures,
therefore be extremely careful,
use caution
, and always follow the instructions.
If during operations any part of the boiler or the exhaust pipe leaks smoke, immediately turn off the boiler
without removing the power supply and ventilate the room. Then, once cooled down, check the reason for
the leak and, if necessary, call the specialised technical personnel.
The boiler is equipped with several devices which intervene in order to ensure safe operation.
CAUTION
:
Safety devices are designed to eliminate any risk of damage to persons, animals or
things, and tampering with them or having unauthorised personnel operate may compromise their
safety.
Safety devices on the boiler are the following:
8.1.1 Fume exhaust pressure sensor
This sensor is connected to the fume exhaust pressure duct. It controls the negative pressure inside the
boiler, monitoring any clogging of the chimney flue, the opening of the combustion chamber door, and the
block of the pellet duct allowing a safe use of the boiler.
When it activates
As already said, the causes that may trigger this alarm are multiple. Below the main ones:
•
If, in the fumes exhaust duct the conditions of correct operation are changed (improper installation, the
presence of obstacles or impediments in the exhaust tube, negligent maintenance, adverse weather
conditions such as persistent wind, etc.).
•
If the boiler flue gas pass contains an accumulation of ash that obstructs the normal passage of the
combustion fumes (poor or negligent maintenance, low quality pellet, improper combustion, etc.).
•
If the boiler has combustion parameters not adjusted correctly (in particular, the low power combustion
parameters).
•
If the combustion chamber door is left open.
•
If pellet accumulates inside the brazier supply duct (result of incorrect combustion).
In each of the cases above, the vacuum pressure sensor (vacuum thermostat) stops electrical power supply
to the pellet feed screw, thus blocking pellet feeding to the brazier and sending an alarm signal to the board.
When the alarm is triggered, the display shows the message "
AL 8 – NO VACUUM
”.
8.1.2 Boiler / Structure temperature sensor
This line boilers are equipped with a manual reset bulb thermostat, which prevents the boiler water
temperature from exceeding 85°C. It is also equipped with a safety thermostat (klixon) which prevents the
structure from reaching excessive temperatures.
When it activates
The bulb thermostat is triggered if the temperature of the water in the boiler exceeds the 85°C threshold while
the klixon triggers if the temperature in the pellet duct exceeds the same 85°C threshold. In both situations
the thermostat interrupts the electrical power supply to the screw feeder, thereby blocking the pellet supply
to the brazier and sending an alarm signal to the board.
The display will show the message “
AL 7 – Thermal safety
”.
8.1.3 Smoke temperature sensor
The smoke sensor is directly connected to the electronic board and keeps operating temperature of exhaust
fumes from the boiler under constant control, allowing safe use of the boiler.
How it works
If fume temperature exceeds the first pre-set temperature limit, the board passes into modulation mode. The
display will show the message “
MODULATE / MAX SMOKE
”. At the same time if, despite passage to
modulation, the fume temperature continues to increase and exceeds the second pre-set safety limit, the
boiler will pass into alarm mode. Pellet flow is interrupted and fume exhaust speed is set to maximum.
