6.3. Wood fuel considerations
As noted earlier in this manual, the moisture content of the wood used to fuel the boiler
should be between 20 and 25%. Hardwoods such as beech, oak, maple, hickory, etc. are
best. While it is possible to burn dry softwood such as pine, spruce, fir, hemlock, etc,. they
will burn faster and require more frequent loading of the boiler than with hardwood. One way
to determine wood moisture content is with a moisture meter (see next page). As a general
rule, hardwood cut, split and stacked for one year under cover is usually ready for burning in
an EKO boiler. Wood properly stored for two years is best.
The manufacturer and distributor
are not responsible for problems related to using wood that is not adequately dry or dense.
Wood density table
wood type
density of green wood [kg/m]3
]
density of dry wood [kg/m]3
]
pine
700
480
larch
760
600
spruce
740
430
fir
1000
450
elm
950
680
ash
920
750
beech
990
730
hornbeam
1080
830
alder
690
530
birch
650
650
maple
870
660
A hydrometer is used to measure the
moisture content of wood.
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