70 3064810_201804
36.Safetydevices
Combustionchambertemperaturesensor(eHLSC)
The combustion chamber temperature sensor is a contact sensor on the indirect
coil. It consists of 2 sensor beads which together act as a high limit safety cut-out
(eHLSC). At the same time, the combustion chamber temperature sensor acts as a
temperature monitor (TM).
The TM shutdown temperature is > 102 °C. When this temperature is reached, the
burner shuts down without locking out the boiler. Fault Þ Fault code 06. Once the
temperature falls below the shutdown point, the boiler automatically restarts.
Thetemperaturelimitershutdowntemperatureis≥108°C.Whenthistemperatureis
reached, the burner is shut down, resulting in a lockout fault Þ Fault code 02. When
the temperature drops below the shutdown point, the boiler will restart once the fault
has been acknowledged.
Boilerwatertemperaturesensor(controlsensor)
Theboilerwatertemperaturesensorintheowpipe,upstreamofthe3-wayvalve
is used as the control sensor. The appliance is controlled via the temperature
determined here.
The maximum possible boiler water temperature 85 °C (factory setting). Exceeding
this temperature causes the boiler to shut down and results in a burner cycle block
(factory setting 7 min.).
Fluegastemperaturesensor
Theuegastemperaturesensorshutsdowntheboilerwhentheuegas
temperature exceeds 110 °C. This results in a lockout fault Þ Fault code 07.
Theuegastemperatureisdeterminedbyasensorinthecondensatepan.
CombustionchambercoverHLSC(thermostat)
The high limit safety cut-out shuts down the boiler if the temperature exceeds 185 °C.
This results in a lockout fault Þ Fault code 01.
Temperaturemonitoring
Systempressuremonitoring
Dryreprotection
The appliance is equipped with a pressure sensor that monitors the operating
pressure in the heating circuit. If the system pressure drops below 0.8 bar, a warning
appears on the display. If the system pressure drops below 0.5 bar, the burner is
shut down without locking out the boiler. Once the pressure exceeds the shut-down
threshold again, the appliance restarts automatically.
The appliance also monitors the water pressure increase in the system every time
the power supply is switched ON. If the pressure does not increase by at least
150 mbar when the pump starts, the appliance will not start. This results in a lockout
fault Þ Fault code 107, i.e. boiler dry.