Wood gasification boilers - DOKOGEN

Wood gasification boiler DC25GD

Ecological wood gasification boilers

Generator Dokogen boilers are characterized with a special chamber which is on both sides laid with special ceramic shaped parts, with primary air inlets in the lower section and with ceramic nozzle and in lower chamber with spherical ceramic parts. Rear flue duct is equipped with a tubular heat exchanger.

Gasification of wood (inverse burning) with subsequent combustion of wood gas in ceramic combustion chamber ensures optimum burning of all combustible components. The air supply and combustion process are controlled with exhaust fan. This allows quick ignition and good combustion of the boiler since the firing up. The flame temperature is 1000 - 1250 ° C.

Inverse burning (gasification) and ceramic combustion chamber enable practically complete combustion with a minimum of harmful exhalations. The boilers meet limits of European regulations for environmental friendly product and belong to 5th class of boiler standard ČSN EN 303-5. Meet the most demanding requirements of the EU - ECODESIGN 2015/1189.
 

 

Advantages of wood gasification boilers ATMOS

  • Option to burn large pieces of wood
  • Large fuel container - long time of burning
  • Tube heat exchanger
  • High efficiency over 90 % - primary and secondary air is preheated to a high temperature
  • Ecological burning - boiler class 5 - ČSN EN 303-5, ECODESIGN 2015/1189
  • Exhaust fan - ash cleaning without dust, boiler room without smoke
  • Cooling loop protecting against overheating – without risk of boiler damage
  • Exhaust fan automatically switches off when the fuel burns out – exhaust (flue gas) thermostat
  • Comfortable ash removing – large space for ash (when burning wood you have to clean it once per week)
  • Small size and low weight
  • High quality
View of top feeding chamber
Filling hole dimensions

 

 

View of bottom feeding chamber
Flame in the bottom combustion chamber

 

Tube heat exchanger
Exhaust fan and flue gas neck

 

Installation

ATMOS boilers must be connected via the LADDOMAT 22 or thermoregulatory valve (three-way valve controlled with actuator) to achieve keeping the minimum temperature of water returning to boiler at 65 °C. The temperature of water exiting the boiler must be permanently kept between 80 - 90 °C.
The default configuration of all boilers includes a cooling circuit to prevent overheating. We recommend installing boilers with accumulation tanks.

MODEL OF DCxxGD BOILERS ARE ONLY INTENDET FOR CONNECTION WITH ACCUMULATION TANKS OF SUFFICIENT CAPACITY WITH A MINIMUM OF 55 LITRES PER 1 kW OF INSTALLED BOILER OUTPUT.

 

Laddomat 22 a termoregulační ventil
Laddomat 22 and thermoregulatory valve
Cooling loop of the boiler

 

Zapojení kotle
Boiler connection with Laddomat 22 and with an accumulation tanks

 

Zapojení kotle s regulací ACD 01
Boiler connection with regulator ACD 01 and an accumulation tanks

 

Regulation of the boilers

Electrical - mechanical - output of the boiler is controlled with a regulating air flap operated with the draught regulator, FR 124 type, which automatically opens or closes the safety valve according to a set output temperature of water (80 - 90°C). When setting the power regulator, much attention should be paid because the regulator has another important function other than power regulation - it also secures the boiler against overheating. A controlling thermostat located on the boiler panel regulates the exhaust fan according to a set temperature (80 - 85°C). A temperature lower by 5°C should be set on the controlling thermostat rather than on the FR 124 draught regulator.

Boilers are also equipped with the waste gas thermostat which serves to switch off the exhaust fan after the wood burns out.

The boiler runs at a reduced output even without a fan - heating is not lost when the electric power fails. At up to 70 % of its rated output, the boiler can be operated without a ventilator (for boilers DCxxGD we do not recommend operation when an exhaust fan is switched off).

Air regulating flap
Exhaust fan and flue gas neck

 

Control panel with standard regulation


Each boiler can be fitted with Equithermal regulation ATMOS ACD 01 for control of the heating system depending on the outdoor temperature, room temperature and time. This regulation is able to control boiler with a fan and many other features.

Control panel with equithermal regulation ATMOS ACD 01
 

 

Technical data

Boiler drawings key

1. Boiler body 18. Thermometer
2. Filling door (upper) 19. Intake duct - air duct
3. Ash-pan door (lower) 20. Main switch
4. Exhaust fan (S) 22. Draught regulator - Honeywell FR 124
5. Heatproof shaped piece - nozzle 23. Cooling loop protecting against overheating
6. Control panel 24. Ventilator control thermostat (boiler)
7. Safety thermostat 25. Door filling - Sibral
8. Regulating flap 26. Door sealing – cord 18 x 18
9. Heat proof shaped piece – for type GD - combustion area side 27. Flue gas thermostat
10. Heat proof shaped piece – for type GD - spherical space 30. Capacitor of exhaust fan
11. Sealing – nozzle - 12 x 12 (14 x 14) 33. Tube heat exchanger
12. Heatproof shaped piece – half moon    
13. Ignition valve K flue gas duct neck
14. Heat proof shaped piece – for type GD - rear face of spherical space L water outlet from the boiler
15. Cleaning lid M water inlet to the boiler
16. Frame shield N filling valve
17. Ignition valve pulling rod P pipe sleeve – sleeve for cooling loop control valve sensor
Boiler dimensions
Boiler type DC18GD DC25GD DC30GD DC40GD DC50GD
A 1281 1281 1281 1435 1435
B 820 1020 1020 1120 1120
C 680 680 680 680 680
D 945 945 945 1095 1095
E 150/152 150/152 150/152 150/152 150/152
F 87 87 87 82 78
G 185 185 185 185 185
H 1008 1008 1008 1152 1152
CH 256 256 256 256 256
I 256 256 256 256 256
J 6/4" 6/4" 6/4" 2" 2"
Technical data
Boiler type   DC18GD DC25GD DC30GD DC40GD DC50GD
Boiler output kW 19 25 29,8 40 49
Specified chimney draught Pa 16 18 20 22 24
Boiler weight kg 376 469 466 548 565
Boiler water volume l 73 105 105 112 128
Fuel chamber volume dm3 85 125 125 170 170
Maximum wood length mm 330 530 530 530 530
Boiler efficiency % 90,3 90,5 90,8 90,5 92,0
Flue gas temperature at nominal output °C 145 132 155 175 183
Specified fuel (preffered)  

Dry wood with heating capacity 15 - 17 MJ.kg1,
water content at least 12 % - max. 20 %, average 80 - 150 mm

Min. return water temperature °C 65
Boiler class   5 5 5 5 5
Energy efficiency class   A+ A+ A+ A+ A+