The Mammutti soapstone injector unit (Patent no. 122079) rapidly recovers the great heat generated by burning through its four channels, thanks to the great thermal conductivity of the Mammutti type of soapstone. This heats the injector unit, which stores an exceptional amount of heat in regard to its mass. As the injector unit recovers the heat from the combustion gas, which is cooled to a safe temperature before reaching the flue.
The higher temperature the storing material is increased to, the more thermal energy it contains.