Premodern heating systems are still a less mentioned and unattended subject in the general history of technology. Especially the discussion about origin and development of the medieval type of hot-air heating remains confusing and contradictory. Due to a new discovered air heating in the Cistercian abbey of Doberan from 1280/1290 A.D. the history of this type of heating occurs in a different light. First of all it appears that hot-air heating systems did not exist in ancient times. Although various authors use two passages of letters by Pliny the Younger to proof the existence of those. The archaeological evidence is still outstanding. Up to this point the classical, also called true hypocaust, persists as the dominant ancient heating system. In the migration period the true hypocaust transforms into the much simpler, but likewise efficient, channel hypocaust. Those remains as a construction without air supply and without any elements of a hot-air heating. However, the air heating arises in the Early Middle Ages. Their first examples are located between the regions of Bodensee and Harz, whereas their genesis stays ambiguous so far. Till 1500 A.D. the hot-air heating becomes the leading version of heating in the medieval areas of Baltic Sea and Central Europe. Thereby the air heating undergoes some crucial developments and improvements. The most important and powerful enhancement is the adding of a stone filled cell above the heating room, which causes a much higher heat accumulation. In the 1990’s Klaus Bingenheimer drafted an enumeration and classification of all known hot-air heatings. Nowadays, this list should be updated with new findings and also be reconsidered in the light of various factors and outcomes through new discovered archaeological sites like the air heating of the Cistercian abbey of Doberan.