© 2017 Brunner GmbH
User guide (1.1)
9
Damp, freshly cut or improperly stored wood has a high water content,
therefore does not want to burn, makes a lot of smoke and gives not much
of heat. Use only firewood which has been stored for at least two years in
a dry place with sufficient air circulation. Because dry wood is much more
calorific, you can save on fuel costs.
For example: Dry wood has a calorific value of approx. 4 kWh/kg, freshly
cut wood only 2 kWh/kg. You will need twice the amount of wood to achieve
the same heating power.
Water content g/kg
wood
Calorific value
kWh/kg
Consumption
raised by %
very dry
100
4.5
0
stored for 2 years
200
4
15
stored for 1 year
350
3
71
freshly cut wood
500
2.1
153
Natural firewood (left) is the
best fuel for fireplaces, but you
can use also wood briquettes
according to DIN 14961-3,
Class A1, length >14 cm (5.51
in), diameter >8 cm (3.15 in)
(right).
What amount of heat will I get when
buying wood per weight?
500 kg freshly cut wood
Water content 50%
500 kg x 2.0 kWh/kg = 1000 kWh
