There is a flue inside the inner box that takes away the smoke of the fire. But i am confused as to how heat is taken from the outer chamber and transfered to the air which gets routed to the house?
It's just radiant heat, like in the old radiator days. The heated inner chamber heats the outer casing and from there the air is heated and by natural convective currents travels throughout the room/house.
A wood furnace burns wood in a sealed firebox to heat an exchanger. With the help of a blower, air is forced over the exchanger or the space in between the two chambers and ducted into the room. It’s basic components include the cabinet or jacket, firebox, blower, access doors for stoking and cleaning, and a small blower to fan the fire when more heat is needed. Some are strictly convection type, but are not as efficient. Hope that explains it ok.
