Spheros Thermo E 320 - Heater Functions; General Heater Functionality Description

Thermo E 200 / 320 4 Heater functions
401
4 Heater functions
4.1 General heater functionality
description
The heater principle is based on a high-pressure atomizer
burner and is monitored by an integrated control unit.
The burner motor powers the fan and the fuel pump. The
fuel pump is coupled to the motor using a coupling.
The fan produces the required combustion air, the
combustion air volume is impacted by the burner motor
speed.
The first CO
2
adjustment was made at Spheros.
For adaption to different applications (extension of
combustion air intake or exhaust line) and after any main-
tenance and repair the CO
2
content is to be readjusted in
a workshop.
The fuel pressure is generated in the fuel pump and
reduced to the required pressure using a pressure limiting
valve.
A solenoid valve releases the fuel via the atomizer nozzle
for combustion in the combustion chamber.
As an option, the fuel pump can be equipped with a nozzle
block preheater. The nozzle block preheater heats the
nozzle holder with the atomizer nozzle at temperatures
below 5°C and thus the fuel. The fuel air mixture is ignited
in the combustion chamber via a high-voltage ignition
spark.
The flame is monitored by a optical flame detector inte-
grated into the control unit.
Depending on the equipment, the heater is switched on
and off using a
• digital timer
• switch
• or climate control.
During heating operation the burner is automatically
switched on and off. For regulation a temperature sensor
is installed in the coolant outlet of the heat exchanger. The
heater is switched on, when the temperature falls short of
a lower temperature threshold (72°C), and is switched off,
if the upper temperature threshold is reached (82°C).
A distinction between parking heating and auxiliary
heating mode does not exists.
For overheating protection of the heater the switching
thresholds are modified by the control unit, if specified
temperature gradients are exceeded (gradient evalua-
tion).
An operating display is available for monitoring the
operating status. The operating display is also used to
output error messages in flash code.