brenndatomu
Minister of Fire
Chimney draft is a column of lighter warm/hot air rising into the colder heavier atmosphere (think hot air balloon) if you have draft pulling with a cold furnace/chimney then you have a breeze blowing across you chimney causing it (remember as a kid how you could blow across the end of a clear straw and watch your drink pull up into it a little bit?) That makes it nice for cold starts!
