5
CHANGES IN THE ELECTRICAL SYSTEM
Changes in the electrical system from chassis number 0E527418
5-28
40A EBERSPÄCHER CAB HEATER (WITH THERMOSTAT UNIT)
The air heater is a separate heater which
functions entirely independent of the vehicle. A
temperature sensor which is installed in the
thermostat unit (E566) measures the cab
temperature. This sensor sends a signal to the
electronic unit (D871) which controls the
heating.
As a result, the cab temperature automatically
remains at the preset temperature. In that case,
the blower is in continuous operation.
OPERATION OF CAB HEATER
The air heater can be activated using the button
on thermostat unit E566. If this button is
switched to the “interior heating” position, the
heater will be activated. A green lamp will now
light up in the thermostat unit.
If the heater is on, it will activate the fan in the
heating unit.
At the same time the fuel feed pump for the
Eberspächer cab heater (B122) is activated, so
that the correct amount of fuel is fed to the
ignition chamber of the heating unit.
If the fuel is ignited, a temperature sensor
(installed in the thermostat unit) will apply a
voltage to the heating unit so that the heating
unit switches off when a certain temperature is
reached.
If the sensor measures a lower temperature
than the temperature preset by the driver (using
the temperature adjusting knob on the
thermostat unit), the heating power will be
adjusted.
In the case of overheating, the thermal
protection will switch off the fuel pump. This will
switch off the heating.
SEE THE SYSTEM MANUAL FOR MORE
INFORMATION
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