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Holz Master - wood gasifying boiler

HolzMaster is a wood gasifying central heating boiler. Thanks to this process, the effectiveness of the boiler is even three times higher than when combusting wood in a traditional way. The boiler is equipped with a fully ceramic furnace, while the charging chamber is lined with stainless steel plates, ensuring low emissions and long life. A purification system is installed in the exchanger which is moved with a lever placed on the side of the boiler. The furnace is controlled by means of a regulator with a PID algorithm and a flue gas sensor that cooperates with the room panel and thermostat, fuel level indicator and the weekly program. As a standard, the weather regulation operates one thermal cycle, and after expansion – up to four cycles. Because of the application of an exhaust fan and a short cycle leg, the possibility of flue gas entering the boiler room has been minimized. The HolzMaster boiler has a large charging chamber for up to 50-cm long chunks of wood.








Power: 20 kW
material: Steel fuel: Seasoned wood
burner: chamotte Efficiency: 90,6%
controller: With PID algorithm and flue gas sensor, possibility of connecting a room panel volume of charging chamber: 120 L


This is explanatory drawing and may differ from the actual design of the boiler. Boiler Holz Master Boiler Holz Master Boiler Holz Master Boiler Holz Master Boiler Holz Master Boiler Holz Master Boiler Holz Master
The Holz Master boiler was constructed based on a steel exchanger, thanks to which the boiler is easy to operate and has high efficiency and long life. The advantages of a steel exchanger were combined with a modern ceramic burner. Such solution enabled also the construction of a device fired with solid fuels, combining the advantages of a manually charged boiler with ecological advantages of biomass-fired boilers.
The upper chamber serves as a combustion chamber and is charged with wood which is then fired and gasified. Doors placed at its top are used for loading fuel, cleaning and maintaining the upper chamber. Moreover, in its lower part the chamber has a washout hole closed with two butterfly holders. Its purpose is the removal of ash gathered at the bottom of the combustion chamber.
The upper and lower chambers are separated with a ceramic burner for combusting gases created during the pyrolysis of wood burned in the upper chamber. Gases flowing through the burner are combusted in the lower chamber. Inspection doors of the lower chamber are used for the operation, maintenance and cleaning of the chamber and the ceramic burner surfaces.
On the back of the furnace there is a pipe exchanger constructed from vertical combustion tubes. It connects the lower chamber of the boiler with the flue gas collector. The exchanger is equipped with a manual purification system which makes it possible to maintain cleanliness of its surface. Flue gas from the exchanger is transferred to the flue gas collector and then directed to the conduit at the top of the boiler through the exhaust fan.
The exhaust fan sucks air into the ceramic burner and combustion chamber. The amount of air sucked into the burner and upper chamber may be regulated manually thanks to dampers placed on both sides of the boiler. The inlet and outlet of heating water, used for connecting the furnace to a central heating installation, are located on the back wall and the top of the boiler, respectively. They have the form of ports with a G 1Ľ” internal thread. On the back wall of the boiler there is also a conduit for carrying away flue gas to the chimney.
The boiler's exchanger is isolated with mineral wool which protects it against heat losses during operation. The casing of the boiler is made of steel plates covered with high-quality resistant powder paint.

Cross-section of the boiler:


Model   HM 20
Height: mm 1565
Width: mm 770
Depth: mm 1075

Dimensions detailed

Model   HM 20
A mm 650
B mm 1455
C mm 135
D mm 290
E mm 935
F mm 160


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