
5VEDEX 1000
For Home Owners
Wood firing
General instructions
The wood is placed on the ceramic grate. Suitable wood
size is 0.3-0.4 m. To facilitate starting the boiler open the
direct damper (5) (pressed in position), this gives a shorter
smoke by-pass.
The combustion process works by reverse combustion.
The air in the boiler enters through the damper (61)
and is pushed down to the lower part of the fire where
combustion is concentrated. The combustion gases are
drawn through the ceramic grate down into the sec-
ondary chamber. The ceramic inserts cause the tempera-
ture to increase to almost 900 °C. More oxygen is supplied
through the secondary damper and is mixed well, thanks
to the turbulent flow, with the hot gases in the secondary
combustion chamber where full combustion is achieved.
Then these pass into the generously sized heat retaining
surfaces. The convection part is equipped with removable
turbulators.
Type of wood, quality and moisture content are determin-
ing factors regarding lighting and fuel consumption. Dry
wood can have a moisture content of 15–25%. If the
moisture content increases to 30%, wood consumption
becomes 10% greater.
The heating value for softwood is about 1000–1300 kWh/
m3. The heating value for hardwood is about 1100-1500
kWh/m3
Extremely dry wood usually produces a large fire where
unusually large amounts of gases are created, resulting in
uneven combustion. To prevent this type of problem, it is
recommended to use hard wood or a mixture of woods
with a moisture content of about 18–20%. Carpentry off
cuts should not be used.
When the wood starts to burn it breaks up, whereupon
combustible gases are created. These burn at tempera-
tures between 300–900°C. The gases make up 3/4 of the
wood’s energy content, the rest is in the created charcoal,
which also eventually burns.
Adjusting the draught regulator
Remove the front panel between the doors by pulling it
straight out. The regulator is installed so that the lever
presses the damper. The door should be closed at the
desired boiler temperature. If, for example, 85 °C is de-
sired, the boiler is fired to that temperature, whereupon
the lever is adjusted so that the damper is closed when the
knob is set to position 4. If a lower or greater temperature
is required, turn the knob to the relevant setting. Moving
between each marking on the knob changes the tempera-
ture by about 7 °C.
It is important that sufficient secondary air is supplied so
that the gases burn off completely.
Lighting for the first time
It is important that lighting is carried out carefully in a new
boiler so that any remaining crystallisation water in the ce-
ramics is condensed slowly to prevent cracking.
Before inserting wood
Check that the boiler and other heating systems are filled
with water. Flue gas thermometer (accessory) should be
installed in the flue pipe.
The turbulators should not be installed during the first few
lightings. This is to increase the flue gas temperature and
produce a better chimney draught until the boiler is lit and
going.
Wood firing