How do chimneys work?
A. Think of a chimney as the engine that drives the heating system. Think of the heat as fuel. Think of the draft as power. The more fuel (heat) you give this engine (chimney), the more power (draft) it will deliver. The hotter the exhaust gases, the more draft produced. Draft is the suction that exhausts fumes and keeps smoke from coming into the room. Insulation in the chimney is important because it helps to keep the exhaust hot until it is expelled outside, and so, increases draft. The chimney works with the stove or fireplace in a kind of feedback loop. Heat in the chimney makes a draft, which pulls in more combustion air, which makes the fire burn hotter, which delivers more heat to the chimney which makes more draft and so on. An Insulated Chimney keeps flue gases hotter and makes more draft with less heat. When you build a fire in a stove connected to a well installed chimney, the kindling ignites easily, draft increases rapidly and you have a bright, hot fire right away withou