Eberspächer B1L Installation Instructions Manual - page 14
Description of operation
Heaters D 1 L and B 1 L are of identical design wherever practicable.
The differing fuel types however make design differences unavoidable.
Control elements
A choice is possible between:
1.Universal switch (22)
Switch position: Heating or Ventilation
If other switches generally used in motor vehicles are employed, they
must be able to take at least 10 A.
2. Timer (23125)
Using the timer, the heater can be switched on at once or the switchon
time can be preselected in advance.
3. Room thermostat (24)
A room thermostat can also be used in conjunction with the universal
switch or timer. It should however be remembered that the load on the
battery is greater and that wear on plugs will be heavier.
Mode of operation
The pilot lamp comes on when the heater is switched on. With a time-
lag of approx.. 5 sets., the hot-air blower starts to convey hot air, the
combustion air blower combustion air and the fuel metering pump fuel,
in exactly metered amounts, into the combustion chamber Fuel and
combustion air here form an inflammable mixture which is ignited at
the glow plug. The combustion gases now pass through the heat
exchanger and activate the temperature switch, which switches off the
glow plug. The hot air is heated at the heat exchanger and passes
through the exhauster into the area to be heated. When the heater is
switched off, the pilot lamp goes off, but the blower motor runs until the
heater has cooled down. Then it is automatically switched off by the
temperature switch.
Controls and safety equipment
The flame is monitored by the temperature switch- This switch acts on
the safety switch in the control unit, which switches off the heater in the
event of a malfunction.
Sequence after switching on:
a) The temperature switch switches off the glow plug when a stable
flame has been obtained. In addition, after the heater has been
switched off, it automatically stops the blower when the heater has
cooled down.
b) If the heater fails to ignite, it switches off automatically not more
than 3 minutes after being switched on.
If a defect in the blower motor has caused the heater to switch off, the
motor current fuse installed in the control unit may have been tripped.
Check it and replace if necessary. The heater can be switched back on
by briefly switching it off and back again. If the motor current fuse
blows repeatedly, have the blower fault remedied. Do not switch the
heater back on more than twice. I f it still does not start, remedy the
malfunction in accordance with the Troubleshooting and Repair
Manual.
c) Should the flame extinguish spontaneously during operation, the
heater will automatically switch off after no more than 4 minutes. It can
be switched back on in accordance with b).
d) The safety thermal cutout switch stops the fuel metering pump if the
maximum permissible temperature for the heating air is exceeded (e.
g. in the event of the heating air ducts becoming blocked). The heater
then switches off automatically. After removal of the cause of
overheating and pressing of the knob on the safety thermal cutout
switch, the heater can he put back into operation by switching it off and
on again.
e) If the glow plug is defective, the temperature fuse on the glow plug
series resistor (D 1 L - 24 V only) has blown, or the electric line to the
fuel metering pump is broken, the heater will not start.
f) If the voltage drops below 10.5 V or 21 V, or rises above 15 V or 30
V, as the case may be, the heater switches off automatically.
IMPORTANT! Heaters with undervoltage safety device may
only be operated with the appropriate control units (with
replaceable motor current fuse),
You can remedy the following malfunctions yourself:
1. The blower cannot be heard after the heater is switched on:
a) Check the 16 A fuse in the cable harness of the heater.
h) Check the motor current fuse in the control unit
(heaters Nos. 25 1531 05 and 25 1532 05 only).
Important! Only the following Eberspacher spare part fuse inserts
(special monitored design) may be used:
for 12 V fuse insert TT 4, blue marking, no 460 26 016 Cat. No., for
two: 25 1531 05 02 00
for 24 Vfuse insert TT 2, yellow marking, no 460 26 000 Cat. No., for
two: 25 1532 05 02 00
The use of other fuse inserts may lead to damage in the control unit in
the event of a fault.
c) Check the glow plug and replace it if necessary.
2. After the heater is switched on, the blower only runs for about 3
minutes, the heater does not ignite and automatically switches off.
Briefly switch the heater off and back on again (not more than twice). If
the heater still does not ignite, have the trouble seen to in a workshop.
3. The heater goes off during operation:
If the fault is due to overheating, switch the heater off, eliminate the
cause of the overheating (e. g. blocked hot-air pipe), press the safety
thermal cutout switch (1) and switch the heater back on.
Please remember that the heater does not start to work until about
5 seconds after being switched on.
The pilot lamp in the universal switch comes on immediately after the
heater is switched on.
The heater must never be switched on while the tank is being filled.
The heater must not be operated in garages.
When carrying out electric welding work on the vehicle, disconnect the
positive pole from the battery and earth it, in order to protect the
control unit.
Only our warranty conditions are valid for warranty claims.
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