Dragon Heat Ltd

Single Pass Dragon and Double Pass Dragon


All Dragons have a thermostatically controlled fan to modify the rate of burning. The ratio of primary air (under the fire) and secondary air (over the fire to burn the gases) can be adjusted to suit your fuel and your heat demand. All Dragons are heavily insulated to reduce heat loss, and the furnace walls are boiler plate – thicker than most to increase the life of your heater. Dragon Biomass have developed two ranges The range you choose depends on the moisture content of your fuel.

Similar to the basic heaters with the same furnace dimensions. However the hot gases pass through 120mm tubes surrounded by water and up to 30% more heat can be transferred into water. The D6, D8, D12, D20, D30, D40 are RHI compliant, allowing you to take advantage of the world’s first long term financial support programme for renewable heat.

When the moisture content of your fuel is likely to be over 22% tarring can occur if the gases drop below dewpoint (58C). By allowing some of the heat to go up the flue the temperature is kept above critical level, thus reducing tarring and maintenance.

  • The 2 and 4 models are fine for timber and small bales.
  • The 6, 8 and 12 models are easy to load with bales and longer wood.
  • The 20 model will accept a 5′ round bale and the 30 will take 2 bales.
  • The 40 and 50 models give the extra width for Heston bales or whole pallets.

  • The easiest way is to check the plate on your existing boiler (1 kW = 3412 btu).
  • Measure the property in cubic metres, divide by 31 = Kilowatts.
  • Count the number of all radiators and refer to the specification page.
  • The outputs in the tables on the Specifications page are shown for loading both once and twice a day, most of the year it will be once a day. Heaters requiring 3 loads a day will need attention late at night. If an accumulator tank is fitted loading can be eliminated at week-ends.

The outputs on the specifications sheet below, are achieved by loading twice a day, most of the year it will be once a day. If an accumulator is fitted loading can eliminate week-end and late night loading.

Calculate your daily rate and multiply by 180 days. The savings made in spring and autumn will be sufficient for the summer. The full specification page for all our dragons can be found  can be found on the Specifications page.

Customer reviews

No reviews were found for Single Pass Dragon and Double Pass Dragon. Be the first to review!