Wood gasifying boiler ATTACK SLX

The wood gasifying boilers ATTACK SLX are intended for economical and ecological heating of dwelling houses, cottages, small plants, work rooms and similar objects. Prescribed fuel for SPX boilers is dry wood. The volume of the SLX boiler´s feeding chamber is unique and ensures longer burning on fuel load. This unique chamber also makes possible to load big wood logs and enables to load the wood logs of half-meter, which saves time by chopping the wood.

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The new boiler line ATTACK 7000 – SLX is equipped with the more efficient tubular exchanger flue gas – water. Special movable turbulators installed inside the exchanger serve to brake and to make the turbulent flow of the flue gas through the exchanger. Thereby it comes to higher heat transfer through the steel exchanger wall into the heating water. There is also option of the dry coat placed around the whole feeding chamber – increased protection against tar creation.


The volume of the SLX boiler´s feeding chamber is unique: 200 – 230 l and ensures longer burning on fuel load. This unique chamber also makes possible to load big wood logs – length of the feeding chamber is 690 and 790 mm and enables to load the wood logs of half-meter, which saves time by chopping the wood.



From technical view it is a boiler line with high efficiency, low flue gas temperature and more effective combustion process. Achieved efficiency of the ATTACK SLX boiler is up to 92 %. By installation of more efficient boiler of the ATTACK SLX line it comes to significant decrease of the operating costs, projected into the fuel savings, in comparison with less efficient boilers that combust same fuel.

From the social-wide view, it is an enviroment-friendly source, combusting wooden biomass, which is a kind of CO2-neutral fuel. Considering the harmful emissions, the average concentration of CO value in the flue gas, is during operation of the LAMBDA version under the level of 200 mg/m3 related to 10 % of O2. Under the valid European norm EN303-5, classifying the solid fuel boilers by efficiency and emissions to individual classes, the ATTACK SLX boiler (version LAMBDA) reaches 25 times lower concentration of harmful CO emisions in the flue gas incomparison with the allowed level of this norm!



Regulation PROFI

The ATTACK PROFI of the „PID“ generation is a kind of the advanced regulator, which enables to modulate the heat output in the ATTACK® wood gasifying boilers by regulation of the fan rotations. The well-readable display shows the necessary information and makes the boiler control easier.
The ATTACK SLX PROFI boiler brings the improvement of the PID regulation to control the fan rotations according to the temperature of water and flue gas and thereby to achieve the optimal efficiency. The regulator uses the advanced Fuzzy logic system for control to regulate the wood gasification system in the optimal way – to ensure the lowest heat loss possible.
The boiler equipped with the regulator ATTACK PROFI „PID” can control the heating system equipped with the following items: a pump for charging the accumulation tank, accumulation tank, circuit pump of heating circuits and room thermostat, by the lowest loss of heat energy possible. The regulator can be connected and set in the way enabling to control the pump of heating circuits and pump to charge the tank for domestic hot water.


Properties – regulation PROFI

  • innovated electronics with fluent PID regulation of the fan rotations according to the flue gas temperature
  • Fuzzy logic – optimal regulation of the operating cycle of wood burning
  • increased boiler efficiency and stable burning
  • several options of control, including the pump to charge the accumulation tank, pump to charge the D.H.W. tank and the circuit pump of the heating circuits
  • option to control the circuit pump by thermostat
  • well-readable display indicating the operation of particular elements




ATTACK SLX LAMBDA Touch electronics consists of the well-readable touch display for quick access to the necessary information and settings. Software of electronics can be anytime upgraded by the USB key. The boiler can be connected to internet by the LAN cable and controlled from the distant point, even by the Smartphone.

The boiler is designed with reference to the user comfort. Thereby is the exchanger cleaned automatically by motor and turbulators. The boiler electronics can be extended with additional external modules to control the heating mixing circuits, D.H.W. tank, solar panels or other automatic boiler ATTACK LAMBDA Touch.


Properties –  regulation LAMBDA TOUCH

  • for boilers SLX and Wood&Pellet
  • smart design
  • new 7″ touch display
  • current status of the boiler
  • change of bolier parameters
  • internet connection configuration
  • remote service diagnostics
  • system update
  • the possibility of connection of external heat sources
  • suitable for complex heating control of buildings
  • equithermal regulation

Boiler parameters

Boiler type
Parameter Unit SLX20 SLX25 SLX30 SLX35 SLX40 SLX45 SLX50 SLX55
Nominal output of the boiler kW 20 25 30 35 40 45 50 55
Output range kW 10 – 20 12,5 – 25 15 – 30 17,5 – 35 20 – 40 22,5 – 45 25 – 50 27,5 – 55
Area of the exchanger 2,95 3,32
Volume of the feeding chamber dm³ 200 230
Dimensions of the feeding hole mm 235×445
Prescribed chimney draught Pa 23
Prescribed chimney draught mbar 0,23
Max. working overpressure of the water kPa 250
Pressure loss of the water (ΔT 10K) kPa 1,9 2,1 2,4 2,7 3,9 4,5 5,2 6,1
Pressure loss of the water (ΔT 20K) kPa 0,8 0,9 1,2 1,6 1,9 2,1 2,4 3,2
Weight of the boiler kg 570 650
Diameter of the flue gas outlet mm 150
Height of the boiler mm 1472
Width of the boiler mm 703
Depth of the boiler mm 1337 1506
Depth of the feeding chamber mm 690 790
Diameter of the riser pipe “E” G 6/4″ G 2″
Diameter of the reverse “F” G 6/4″ G 2″
Protection class IP 21
Electrical input at the nominal output W 42 78
Electrical input at the minimal output W 31 52
Electrical input at the standby mode W < 15
Boiler efficiency % 91,8 91,6 90,3 90,3 90,4 90,4 90,3 90,3
Boiler class 5
Temperature of the flue gas by the nominal output °C 165 170 175 180 165 170 170 180
Temperature of the flue gas by the minimal output °C 130 135 140 145 135 140 140 145
Mass flow of the flue gas by the nominal output kg/s 0,018 0,02 0,021 0,023 0,027 0,029 0,031 0,033
Mass flow of the flue gas by the minimal output kg/s 0,008 0,011 0,014 0,016 0,017 0,021 0,022 0,023
Max. noise level dB 65
Class and type of the fuel A, Wood logs with relative humidity of 12 % – max. 20 %, ∅ 50 – 150 mm
Average wood consumption kg/h 5,2 6,5 7,8 9,1 10,4 11,7 13 14,3
Indicative consumption of the wood per season 1 kW = 1 m3
Max. length of logs mm 650 750
Time of burning by nominal output * h 8 7,2 6,5 5,8 6 5,1 4,6 4
Volume of the water in the boiler l 117 136
Recommended volume of the accumulation tank l 1000 – 2000 2500 – 3500
Voltage V/Hz ~230/50
Range of the setting the temperature of the heating water °C 65 ÷ 85
Capacity of the contacts of the boiler regulator (PROFI version) 2 A/ ~230 V

* dependent on type of fuel and the perfection of feeding the chamber by wood.


Instructions for Use


User manual for correct installation, operation and cleaning


Energy Labels


Information Letters



Certificate SLX (B-00678-19 EN)


Certificate SLX (E-30-01049-14 CZ/EN)