1101
Illustrations may differ from actual product
Subject to printing/proofreading errors
1 6
OPERATION
POWER
FLAME
ALARM
Normal operation
High
Low
Start phase
Start delay
Cooling phase
Flame
High temperature in downpipe
Failed start
High ambient temperature
Fan not working
Excess pressure, combustion chamber
Starter element not working
Operation, start to stop
Operation, start to stop
The Viking Bio's operating process is reminiscent of that of an oil burner.
One major difference is that the start and stop phases take longer. Under
normal conditions it takes four to five minutes until the flame is estab-
lished.
The burner's operating cycle from start to stop is divided into four phases:
I. Start
II. Establish flame
III. Operation
IV. Cooling/blowing clean
Start
Start conditions:
• Overheating protection, thermostat and any hatch switch closed.
• Any alarm reset.
• The burner receives pellets.
• The thermostat requests heat.
If start delay is selected, the 'OPERATION' indicator will flash during the
time for which the delay is set.
• The fan starts and operates at maximum speed for twenty seconds to
ventilate the boiler and flue gas duct.
• The fan stops. A start dose of pellets is supplied and the ignition ele
-
ments begins to heat. For the factory-set start dose, the feed auger
rotates through roughly two revolutions, which produces approximately a
decilitre of pellets.
• The fan operates periodically at low speed. The 'FLAME' indicator
flashes. When the photoresistor senses that there is a flame, 'FLAME'
lights up constantly.
The burner has three attempts to start. The first attempt is described
above. If no flame is established during the first attempt, the fan will stop
for a brief time and then operate at low speed while the ignition element
is also in operation. The third attempt to start is identical to the second.
If there is no flame after the third attempt to start, the fan stops for a
brief time and then speeds up in three steps to high speed.
The burner normally ignites during the first attempt to start and the
flame is established after four to five minutes. If the burner fails to create
a flame as described above, it will stop and produce the 'Failed start'
alarm. The most probable causes of this are excessive draught, the grate
is in the incorrect position or the burner is not receiving pellets.
Establish flame
• The burner is in operation with a flame.
• The fan speed increases in steps to establish a stable bed of embers on
the grate.
• Pellets are supplied. The feed auger rotates through roughly one revolu
-
tion for each supply. The pause time depends on the power set.
If the flame disappears during this phase, the control switches to the start
phase but no pellets will be supplied.
Operation
• The fan speed is determined by the power set. The 'POWER' indicator
lights up constantly or flashes, depending on the operating mode. The
'FLAME' indicator lights up constantly.
• Pellets are supplied. The feed auger rotates through roughly one revolu
-
tion for each supply.
If the flame disappears during operation, a smaller volume of pellets is
supplied and the ignition element attempts to create a flame. 'FLAME'
flashes and lights up constantly when there is a flame.
The burner then switches to 'establish flame' to create a stable bed of
embers in steps and then switches to the operation phase.
If the attempt to create a flame fails, the burner will stop and produce a
'Failed start' alarm.
The reason why the flame disappears may be high draught, no or uneven
pellet supply or a clogged grate.
Cooling/blowing clean
• Stoppage by thermostat.
• Pellet supply ceases.
• 'POWER' indicator flashes, one long + two short.
• The fan operates at maximum speed and continues at this speed for 90
seconds after the flame has gone out. This is so that all pellets on the
grate are combusted. The 'FLAME' indicator goes out.
• For four cycles, the fan is in operation at maximum speed, blowing clean,
to blow away the ash from the grate and to cool the burner.
• The burner stops. Only the 'OPERATION' indicator is on.
Long operating time
When the heating requirements are high in relation to the burner's power,
the burner's operating time is extremely long. To retain good combustion
and reliable operation, after around three hours of operation the burner
switches automatically to its cooling/blowing clean phase to blow away
the ash residue that is formed on the grate. The burner starts operating
again automatically.
