MORE HEAT WITH LESS WOOD

MORE HEAT WITH LESS WOOD
THE OVEN
BURN-OFF PRINCIPLES OF FURNACES
Under burn-off and side burnoff are more efficient and
produce less emissions.
However, they are more
complex, which makes them
more expensive.
Primary air supply
Flue gas
Burn-through
Upper burn-off
Under burn-off
Side burn-off
Fig. 1 Burn-off principles of stoves and boilers hand fed with wood logs
FUEL TYPES
WOOD HEAT SYSTEMS
Central heating
Single room
Fig. 2 Illustration of a wood pile, split wood bag,
hardwood briquettes, pellets, kindling (from top
left to bottom right)
Open fireplace
Closed stove
Modern stove
Thermal storage heating stove
Wood log boiler
Room heater
Central heating stove
Pellet stove
Pellet stove with water system
Cooking stove (wood log or pellet)
Cooking stove with water system
Fig. 3 Examples of wood firing types: open fireplace, cooking stove, closed fireplace, pellet stove, tiled stove
Circulating
Umluft
air
Verbrennungsluft
Combustion air
Abgas
Flue gas
EXAMPLES OF OPERATION
VorratsPellet
behälter
reservoir
Auger
Förderfeeder
schnecke
Elektrische
Electrical
Zündeinrichtung
ignition
Door with
Feuerraumtür
viewing
mit Sichtscheibe
glass
Brennertopf mit
Firepot
Luftdüsen
Aschekasten
Ash tray
AbgasExhaust
gebläse
fan
Fig. 4 Closed fireplace (hand crafted),
burn-through principles
Sources:
Hartmann, H., FNR, Handbuch Bioenergie Kleinanlagen, 2013
HKI Industrieverband, Haus-, Heizen- und Küchentechnik e. V.
Fig. 5 Modern stove (industrial built
appliance), burn-through principle
Fig. 6 Upper burn-off in a pellet stove
Umluftgitter
Air grid