27
EN
according to DIN EN 230:2005). The oil firing unit Siemens LOA 24 may
be combined with all presented flame monitoring systems, while the oil
firing unit Siemens LMO 14, according to DIN EN 230:2005 may only be
used in connection with the KLC 2002 optical flame detector and with the
ionising flame control ZTÜ. The sequence of the program of both oil firing
units only differs primarily in the program times. The advantages of elect-
ronic firing units over electromechanical firing units rests in the comforta-
ble display of status and interference messages by blinking codes, and
the possibility of electric remote unlocking.
The starting sequence of the burner starts as soon as the boiler thermo-
stat is closed and current is flowing on the T2 terminal of the Euro plug.
In this switching status the oil pre-heater is provided with current through
the terminal 8 (see Chapter 6). As soon as the pre-heating phase is con-
cluded (release time 145 seconds at an initial temperature of 31°C) the
heat valve, which is installed into the oil pre-heater, is closed by means
of which current is available on terminal 3 and the motor starts up. The
oil firing unit simultaneously initiates the time of pre-purge with pre-
ignition. If no flame is detected after the expiry of pre-purge the control
will open the solenoid valve of the oil pump and the fuel will be injected.
However, if during pre-ventilation a flame or a secondary light appears
the unit will be de-activated and the burner will be locked. The unlocking
of an electromechanical oil firing unit (Siemens, LOA 24) is only possible
after the cooling of the bi-metal (approximately 50 seconds after the error
shutdown). This attendance time will not apply for electronic oil firing unit
(Siemens, LMO 14).
Upon the release of fuel the ignition will be “switched on” for another time
span (post-ignition). With a normal start-up the flame will be generated
within the safety time. The burner will then remain ON until the boiler ther-
mostat opens and the voltage drops on terminal T2. But if the flame is not
generated within 10 seconds after the release of fuel (safety time), or if it
goes out within this period of time, the solenoid valve will be closed and
the burner locked. An automatic attempt to restart will not be carried out.
The fault clear button of the burner must be activated to re-commission
the burner. But if the flame extinguishes after the expiration of the safety
time the burner undertakes a new start attempt with pre-purge and pre-
ignition.
The oil-firing unit is low voltage protected. In the event of mains voltages
below 165V the start-up of the burner will be prevented, and respectively
a fault shutdown will be invoked during the operation. A minimum voltage
of 175V is required to initiate the start-up sequence.
Program process of oil firing unit
In the event of a fault shutdown the outlets for the fuel valves, the burner
motor and the ignition device are principally switched off immediately (<1
second). After the fault shutdown the burner will remain locked and the
fault signal lamp lights red. This state will also remain in the event of in-
terruption of the mains voltage.
The LMO14 electronic oil firing unit also features a visual operating display
and trouble-shooting diagnosis that are displayed through the multi-co-
loured LED (red/yellow/green) in the unlock button.
Heat demand
Oil preheater
Thermostat oil preheater
Burner motor
(Blower/Pump)
Ignition
Magnet valve
Signal flame
th
ts
tpoi
tprp,tpri
th
Heat uptime oil preheater
tprp Pre-purge (13 s)
tpri Pre-ignition (13 s)
tpoi Post-ignition (15 s)
ts
Safety time (10 s)
Operating mode
ED flashing code
Waiting time
OFF
Oil pre-heater is heating
yellow
Permanently
Ignition phase, ignition triggered
yellow
Blinking
Operation, flame OK
green
Permanently
Operation, flame insufficient
green
Blinking
Secondary light at start-up of burner
green-red Blinking
Low voltage
yellow-red Blinking
Fault, alarm
red
Permanently
Error code output
red
Blinking
PC interface diagnosis (specialist required)
red
Flickering
After the fault shutdown of the oil firing unit LMO14 and the permanently
shining red LED fault signal lamp, the visual troubleshooting diagnosis
may be activated by pressing the unlock button for >3 seconds. During
the troubleshooting diagnosis the control outputs are without current and
the burner remains switched off.
Cause of fault
LED blinking code
No flame formation at the end of the
safety time
red
2 x flashing
Secondary light when starting the burner
red
4 x flashing
Loss of flame too often during the operation
(limit of repetition)
red
7 x flashing
Time monitoring of oil pre-heater
red
8 x flashing
Wiring error or internal error, permanent error
at output contacts, other errors
red
10 x flashing
Leaving the troubleshooting diagnosis and re-starting the burner occurs
by a single short-term, approximately 1 second (< 3 seconds), activation
of the unlocking button.
3.
Initial operation
3.1 Assembly of the burner
Shift flange model:
– Assemble the shift flange including the sealing by means of the atta-
ched M8 screws onto the heat generator. The clamping screw of the
shift flange arrangement must be positioned upwards.
– Push the burner with burner tube (without recirculation tube) into the
flange until the edge of the recirculation opening that is facing the bur-
ner connects flush with the insulation of the inside of the combustion
chamber. The recirculation openings must not be covered with the com-
bustion chamber insulation (see illustration).
– Tighten the clamping screw of the flange. Thereafter put on the recir-
culation tube and twist it into the bayonet socket until it locks.
Unit flange model:
– Assemble the flange and the sealing including the burner tube, by me-
ans of the attached M8 screws onto the heat generator. Make sure to
orientate the wedge shaped unit flange so that the thicker side points
downwards.
– Insert the burner without the burner tube into the flange and fasten it
by means of the service screw. Make sure that the edges of the recir-
culation opening that is facing the burner connects flush with the insu-
lation of the inside of the combustion chamber. The recirculation ope-
nings must not be covered with the combustion chamber insulation (see
illustration).
– Put on the recirculation tube and twist it into the bayonet socket until it
locks.
The re-circulation openings should not be covered by the insulation of the
combustion chamber.