Adobe heater functioning

An adobe heater operates using the countercurrent principle. By using this principle, the hot combustion gases first flow upwards, then all the way down through the whole heater. On this long route the hot gases transmit their heat to the stone mass of the heater before they leave through the chimney. The great mass of the masonry heater accumulates the energy from the gases and radiates it into the house efficiently and for long periods. Because of the very efficient combustion of the fire, flue gases are very clean and the heater will burn extremely economical.

The temperature measured in the combustion room is about 1000 C, while the flue gas temperature measured in the chimney is about 200 C. The stove mass,which varies from 500 to approximately 7000 kg, depending on size and design, accumulates this heat difference. With regular firing a heavy heater will stay warm continually and will therefore radiate pleasant warmth at all times. Due to the higher heat capacity a heavier heater needs to be fired less often compared to a lighter one.

Our solid masonry heaters have an output of 2-4 kW and can provide 48-96 kWh every 24 hours. In a well-insulated house a massive heater remains warm longer and sometimes only needs to be fired once every two days in order to heat the whole house. Adobe heaters are ideal as the main heating source, but can also be used without any problems alongside an existing heating system.

Adobe masonry heaters are fired with wood, which completely decomposes in a specially designed firing room. In this firing room the fire not only gets oxygen through the grate but also through specially designed slits in the side or back. This allows so-called secundary combustion to take place, where flue gases decompose totally. The fire receives sufficient oxygen at all times, making it clean and efficient. This means that the firing room and the ceramic window are clean, little ashes and soot remain and there is minimal emission of smoke. The energy from the wood is transferred to the heater with an efficiency of approximately 85%. This efficiency is in stark contrast with for example a metal stove which has an efficiency of approximately 40% or an open fireplace with an efficiency of approximately 5%. Each adobe heater from Vuurmeesters comes with extensive oral and written instructions to achieve the best combustion, adapted to the specific design of your heater.

Wood is a renewable biofuel and is carbon-neutral. In our stoves you can fire all types of untreated wood without problems. Willow, poplar, pine and pallet timber burns in our stoves without the problems frequently encountered in metal stoves, such as soot and chimney fires. A single basket of dry wood is enough for a whole day of comfortable warmth. Freshly cut wood must, depending on the type of wood and the humidity, dry for one to two years. Chopped wood that is bought commercially often has a moisture content of 20% to 40%. It is therefore advisable to give this wood some additional time to dry as well. A moisture content of approximately 15% or lower is optimal for all varieties of wood.
The specific energy value of a log of wood varies by wood species, both by volume and weight.