Recuperative burners are primarily used for indirect heating in condensed furnaces. They work as counter-current heat exchangers and use the energy of hot waste gasses for pre-heating the fuel gasses. This principle increases the efficiency considerably.

In the recuperative burner high requirements are put to the material just like in conventional indirect burner systems. On the one hand, the temperatures are high, regular changes of temperature have to be coped with without damage and, moreover, the components are in contact with the hot fuel and waste gasses. This means a high thermal conductivity forms the basic precondition since a high efficiency can only be achieved in this way. These very demanding conditions are well fulfilled by ceramic materials which, moreover, have a considerably lower specific density compared with steels and which, hence, have a much lower thermal mass. Since a direct contact of the fuel and waste gasses with the atmosphere of the furnace has to be avoided in indirect burners, the ceramics used have to be manufactured to be gas tight, i.e. without open porosity. Furthermore, this improves the corrosion stability. For this reason, silicon-infiltrated silicon carbide ceramics (SiSiC), in which free metallic silicon completely fills the remaining porosity of the ceramic frame, are best suited for this application.