Fireplace’s Fire Plus system ensures an optimum combustion of the flue gases generated, at low harmful emissions. Combined with effective heat exchange system, fireplace-stoves give high efficiency.
After the first batch of wood used to make a fire is burnt to glowing embers, the next step is to place on it the amount of wood complying with the output of the fireplace-stove, and wait until it lights. This is the first stage of the combustion process, i.e. the period of „high flames” when gases arising from the wood are burnt.
In the second stage of the combustion process, the size of flames is reduced. That is the time when residual (elementary) carbon is burnt. This time the embers are of light colour in the firebox and the flames are very small.
Low harmful emissions and high efficiency combustion can only be achieved if the amount of air required for combustion is available in the right place in all stages of combustion. Long retention time in the firebox of gases mixed with air required for combustion and the hot firebox itself have a favourable influence on combustion.
This effective method of firing technique can be achieved by Fireplace’s Fire Plus system. Primary air entering from the base of the firebox through the grate is supplemented by secondary air („glass washing” air) and terciary air entering through slots at various heights of the firebox.
Wood, wood briquette and brown coal briquette burn with high flames. In the flame range and afterwards in the range above the embers, secondary and terciary air is introduced by the system to the firebox in such a way that as a result of the mixture of gas and air required for combustion as well as long retention time of gases in the firebox, perfect combustion should occur. Good quality lining of the firebox ensures high temperatures resulting in an increase of the efficiency of combustion.
After that, heating gases pass through one or more baffle systems in the upper part of the stove to enter the heat-exchanger which usually consists of a pipe system. Here heating gases lose heat again.
Finally, flue gas exits from the fireplace-stove through the flue gas pipe-end and is passed, through a connection piece, to the chimney. Depending on the type of the stove, the length of the connection piece and the method of connection, flue gas enters the chimney with temperatures about 230-300 degrees. The remaining amount of energy ensures the necessary delivery pressure in the chimney which is the „engine of the stove”.