Eberspächer B1LC compact Operating Instructions Manual - page 17
Functional d escrip tion
Controls
1. Operating unit
The operating unit is for switching the heater on and off
and for setting the desired cabin temperatures (intake air
temperature between 10 °C and 30 °C). The integrated
green LED indicates wheter the heater is on.
2. Heater timer (optional)
With the heater timer, the heater can be switched on or off
immediately or the switch-on time preset (between 24 h
and 7 days depending on version).
Mode of operation
Switch-on
The green pilot light comes on when the heater is switched
on. The glow plug is switched on and the blower starts up at
a low speed.
Note: If the heat exchanger still contains residual heat, only
the blower runs (cold-blowing phase). The start-up procedure
commences after residual heat has dissipated.
Start-up procedure
Fuel feed starts after approx. 15 seconds. The fuel/air mixture
ignites. Blower speed and fuel feed are increased continuosly.
Once a flame has been detected and the combustion process
has stabilized, the glow plug is switched off. The heater is
heated up rapidly in the >P0WER< setting at maximum heat
flow until the heat exchanger reaches its operating tempera
ture.
Note: The duration of max. heat flow is temperature-
dependent.
Control during heating
During heating, the cabin temperature or the intake heating
air temperature is measured constantly and compared with
the temperature set at the operating unit. If the measured
temperature exceeds the desired cabin temperature, the
heater switches to the >LOW< setting and continues to run at
low blower motor speed. If the heating capacity in the >LOW<
setting is insufficient, the heater switches to the >MEDlUM<
setting. The blower continues to run at low speed. In most
cases, the LOW-MEDIUM-LOW control sequence at low
blower speed w ill supply the required heat.
If the >MEDIUM< setting is not sufficient, the heater switches
back to >HIGH<. This again entails full blower speed. If, in spe
cial cases, an even lower heating capacity is required than the
heater delivers in the >LOW< setting, the heater switches to
the >OFF( setting. Restart is generally in the >MEDIUM< setting
at low blower motor speed.
Switch-off
When the heater is switched off, the green pilot light goes
out and the fuel feed is shut off. The blower continues to run
to cool down the heater.
The glow plug remains switched on for another 15 seconds to
clear the heater of combustion residues.
Note: If no fuel feed took place during the start-up procedure
or if the heater is in the >OFF< setting, the heater is switched
off immediately without afterrun.
Once the normal afterrun period has elapsed, the heater is
constantly after-ventilated at minimum blower speed (in re-
circulated-air operation only) until the heater is restarted.
Controls and safety equipment
The flame is monitored by the flame sensor, and the max.
permissible temperature by the safety thermal cutout switch.
Both affect the control unit, which shuts down the heater in
the event of faults.
1. If the heater fails to ingnite within 90 seconds of fuel
starting to be pumped, starting is repeated as described.
If the heater still fails to ignite after 90 seconds of fuel
pumping, fault shutdown takes place.
2. If the flame goes out spontaneously during operation, a
restart is first attempted.
If the heater fails to ignite within 90 seconds of fuel
pumping, or if it does ignite but goes out again within 10
minutes, fault shutdown takes place.
The heater can be reset by switching it off and then back
on again.
3. In the event of overheating the safety thermal cutout
switch is operated, the fuel supply is interrupted, and fault
fault shutdown takes place.
If the fault shutdown is due to overheating, the switch-
on pilot light (green) in the operating unit flashes at a
steady rate. Further fault indication signals can be called
using an additional unit - also see Troubleshooting and
Repair Manual.
Once the cause of the overheat has been removed, the
unit can be restarted by switching it off and then back
on again.
4. If the voltage drops below 10.5 or 21 V or rises above
16 or 32 V as the case may be, fault shutdown takes
place.
5. If the glow plug is defective and the electric cable to the
metering pump is interrupted, the heater w ill not start.
6. When the heater starts the operation of the blower mo
tor is checked once. If it does not start, the heater reacts
as for fault.
During operation, the blower motor is monitored in cyc
lic manner (every 4 minutes). If the motor speed is below
the allowed limit, fault shutdown follows.
7. When the heater is switched off the glow plug is swit
ched on during the delayed shutdown for about 30 se
conds (after-glow) to clear the heater of combustion
residues.
Please note:
When carrying out electric welding work on the vehicle, dis
connect the positive terminal from the battery and earth it in
order to protect the control unit.
The heater must always be switched off when the tank is
being filled.
The heater must not be operated in garages.
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