Stroco 15.00 M, Service Instructions Manual

Page: 17 / 38

DESCRIPTION OF FUNCTIONALITY - OPERATION
PAGE 17
T he heater can be started using the main switch on the dashboard. Alternatively, a stating clock can
function as main switch.
The start-up process connects control current from the installation (12V or 24V battery).
The main power supply is connected directly to the heater’s control system, which controls the power
supply to the heater.
The pump relay is activated immediately on start-up to start the circulation pump. The pump runs
constantly when the main switch is activated.
The control thermostat sends a signal to start up the combustion unit when the boiler temperature
drops below the set value.
During the pre-ventilation period, the ignition electrodes (sparks) receive current, the fan motor runs,
and the nozzle pre-heater is engaged.
The fuel pump solenoid valve is switched on approx. 60 seconds after system start-up to release fuel
to be vaporised in the nozzle. The safety timer is engaged at the same time.
Once the flame is established, the nozzle pre-heater and ignition are disengaged. The starting
sequence is now complete, and the combustion unit remains operational until the control thermostat
cuts it off and the ventilation period begins.
When the control thermostat completes the circuit again, the starting sequence repeats with a
pre-ventilation period of 10 seconds.
The control system’s monitoring is focused primarily on the combustion process.
If the fuel does not ignite on start-up, the safety relay remains active. After approx. 10 seconds, the
safety relay disconnects, and post-ventilation begins.
If the flame goes out during operation, the safety relay switches on the ignition to attempt a restart. If
the fuel does not ignite, the safety relay disconnects, the fuel supply stops, and the alarm is activated.
If the fuel does ignite successfully, the combustion process continues until the control thermostat cuts
it off.
The electronic circuit is controlled automatically, so fuel supply stops in case of component failure in
photoelectric or engine circuits. In case of abnormal operating conditions, such as flame failure
during operation or false light during pre-ventilation, the automatic safety system stops the heater
and activates Alarm functions. It is therefore important to install the LED lamp that displays this
alarm from the system within the driver’s field of vision so that potential errors can be detected
quickly.
The control system has an integrated motor voltage regulator, which maintains a constant approx.
21V/11.8V on the fan motor.
The heater’s pre- and post-ventilation and low voltage logic is also controlled by the automatic system.