Prefabricated condensation flue for heating system with low flue gas temperature

摘要

Heating system with low flue gas temperature is provided with a ready-made condensation flue having an inner pipe (2) through which the flue gas passes and an outer wall (5) extending over several storeys, with an air gap (6) being formed between the tube and the wall. The wall comprises a one-piece outer shell (7) of cast reinforced concrete and a one-piece thermally insulating inner shell (8) around which the outer shell is cast. The inner shell is prefabricated from separate pipe sections. The outer shell is preferably manufactured from structural lightweight concrete, with a dry density of 1.3 to 1.8 kg/dm3 and a thermal diffusivity of 0.80 W/mK, while the inner shell is of porous non-structural concrete.