8
Värmebaronen Vedolux -350, -450 and -650
Combustion control
The combustion in Vedolux boilers is set automatically
via the O
2
value for optimum combustion
Output reduction
A high boiler temperature produces a high charging
capacity but increases the risk of an over temperature
situation. To minimise this risk, reduce the boiler’s
power by approximately 20% if the boiler temperature
exceeds the desired boiler temperature by more than
35°F. The power is reduced by closing the primary air
damper so that the flue gas temperature falls.
Switching off the boiler
The boiler can be switched off automatically or manually.
When the wood has been burned up, the boiler is
switched off via the O
2
value (there is also an option
to do this via the flue gas temperature). The boiler is
switched off when it has been in operation for at least
45 minutes and when the O
2
value has subsequently
been over 14% for 15 minutes. After the boiler has
been switched off, the flue gas fan is stopped and the
primary air damper closed. The secondary air damper
is open 25% until the flue gas temperature is lower
than 210°F. This position should be standard as it
reduces the cooling of the boiler via the chimney. The
remaining embers make the next firing easier and
result in the minimum possible emissions during firing.
If the boiler is set to be switched off via the flue gas
temperature, it is switched off 15 minutes after the
flue gas temperature is less than 25% of the nominal
value. This option should only be used if the wood is
bulky or damp.
Residual heat
If the boiler’s temperature rises to 113°F after the
wood has burned up, the charging pump starts in
order to withdraw the remaining heat from the boiler.
The charging pump is in operation for at least three
minutes.
Frost protection
If the boiler temperature falls to 45°F, the charging
pump starts. This reduces the risk of freezing on
account of the flowing water.
When the boiler temperature rises to 46°F, the charging
pump is switched off.
Restart after power cut
When the power returns, the secondary air damper
is opened fully for 30 seconds so that the chimney
is ventilated. The operating status is then restored to
the status before the power cut.
Hatch lock
The boiler’s hatches are locked to prevent
unintentional opening.
Safety functions
If the boiler has not been fired for seven days, the
flue gas fan starts for two minutes and ventilates the
boiler with fresh air to keep it dry. The charging pump
operates at the same time for ten seconds.
Over temperature in the boiler
When the accumulator tank is fully charged
because too much wood has been inserted, the
boiler temperature rises to over 194°F and an over
temperature situation arises. In this case, the flue gas
fan is stopped and the primary air damper is closed,
while the secondary air damper is opened to 25%.
indication flashes and the display shows:
Over temp.
DO NOT OPEN!
Max. temperature thermal
relay, STB
If the boiler temperature rises over 203°F, the max.
temperature thermal relay is triggered. The reason
may be too much wood or a fault in the heat removal,
charging pump or charging valve. The flue gas fan
and charging pump are stopped and the primary air
damper is closed, while the secondary air damper is
opened 25%. indication lights up and the display
shows:
STB triggered
Reset!
Operation