Wood burning kilns can reach temperatures of 1300 degrees Celsius with natural draft, but require dry timber, preferably hardwood, and often several days to reach this. Wood firing can thus be used for smelting non ferrous metals, and is are hot enough for porcelain. However, to reach temperatures high enough for iron and steel wood is not sufficient, and it needs to be converted to charcoal.
Additionally most charcoal forges or furnaces require forced draft to reach temperatures hot enough to reduce iron ore (typically 1900 degrees C at the bottom, 1300 degrees C at the top), and the additional carbon that is present in charcoal to aid the reduction process.
I guess also at high altitudes there is a need for much greater volumes of air than at sea level. Iron furnaces were present in the French Alps at heights from 500 to 1000m, but the Andes have an average height of over 4000m.
Large volumes of air require some form of mecahnical blower - bellows or fan, and a power source, e.g. water wheel - so most iron and steel works were situated at the lower end of valleys with a good flow of water.
Small pot bellows, as used in the African furnaces can be used to smelt small ingots of iron, enough for one or two blades - but again the fuel is charcoal, not wood.
Iron working tends also to a result of a stable population, not a migrant community as much of North America indian populations were - they tended to pack up their tents and follow the herds of bison - so I guess this explains why it was never developed there, and the Inuit only used meteroric iron...
The stable societies of the central and south Americas, e.g. Maya amd Inca, did have metal working as demonstrated by their gold objects - but it would appear they never progressed to iron smelting. Question - did they have the knowledge of charcoal making?? This may have been a significant limiting factor......
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