3
General instructions about the fuels wood and coal
Logano G201 - Subject to technical modifications.
8
3
General instructions about the fuels wood and coal
Wood and coal can be used as fuels.
The flue gas temperatures are generally 212 – 392 °F.
Depending on local conditions, fuels used (wood or coal),
and how clean the boiler is, these values can be
exceeded.
3.1
Wood firing
Prescribed is split and dried wood with a diameter of
6 inches and a maximum wood humidity of 20 %.
Only use dry, natural, chunky wood. With a wood humidity
of more than 20 %, the boiler output is reduced. In addi-
tion, there can be increased tar formation, which reduces
the life span of the boiler. The specified output values and
the unfettered function of the boiler can only be guaran-
teed with a maximum wood humidity of up to 20 %.
As substitute fuels, the following are permissible (reduced
output and shorter maintenance intervals): wood briquets
and wood chips.
3.2
Coal firing
Best suited are anthracite coal and coke – any kind of
lump 1 (0.8 – 1.6 inches). The burning times for coal are
significantly longer than the burning times for wood.
As substitute fuels, the following are permissible (reduced
output and shorter maintenance intervals): anthracite coal
and coke type lump 2 (0.4 – 0.8 inches) or fragments
(1.6 – 4.0 inches) and pressed fuels.
3.3
Condensate and tar formation
Improper operation of the boiler causes excessive con-
densate and tar formation. This way, damage to the boiler
and the flue gas system can occur.
When heating up the cold boiler, water condenses in the
boiler, which runs down on the interior walls. This way,
you might think that the boiler is draining off. This "sweat-
ing" of the boiler ends as soon as the ashes accumulate
on the interior walls of the boiler.
In case of operation at low boiler temperature (return temp
less than 131 °F) and fuel with too high a humidity con-
tent, condensation can also form on the heating surfaces.
Here too, the condensation runs downwards.
Heating with too low a boiler temperature causes tar for-
mation and can cause premature damage to the flue gas
system due to sooting.
V
Follow the operating instructions for the boiler.
V
Operate the boiler at the recommended operating tem-
peratures.
V
Only heat the boiler with the recommended fuels
(
Æ
Chapter 3.1 and 3.2).
V
Remove tar accumulations with the cleaning scraper
when the boiler is warm.
DANGER:
Danger of fatal accident due to
escaping carbon monoxide (CO)!
In case of firing with brown coal, the boiler
can silt up and CO can escape.
V
Do not use brown coal for firing.
WARNING:
Health and/or system damage
due to the use of unsuitable fuels!
The use of unsuitable fuels can create mate-
rials that endanger health and/or the heating
system.
V
Do not use plastics, household waste,
chemically-treated wood, old paper, chips,
bark or chipboard waste for firing.
Boiler type
Maximum length of split
or chipped wood
27
15 ¼ inches
35
19 ¼ inches
40
27 ¼ inches
Tab. 1
Maximum length of split or chipped wood
Type of
wood
Heating value
(with wood humidity of 20 %)
Weight per
cord LBs
BTUs per cord
air-dried wood
Beech
3000
24,000,000
Oak
3250
26,000,000
Pine
1800
17,000,000
Spruce
2100
18,000,000
Tab. 2
Energy value of various types of wood
