External air or direct air? An important decision when you decide to fit a stove in your new house. Especially, when you have gone to great lengths to ensure that the house is virtually air tight and that very little heat (and therefore air) is allowed to escape.
The external air feature in a stove will allow the appliances main combustion air to be taken from outside of the buildings. Therefore, external air should be a prerequisite for any stove planned for a new home.
This makes the stove more efficient and safer because it is not using the warm air it has just created (well, at least not much) or the air that the room's occupants will also need to breath.
In a new dwelling an external air supply to the stove ensures that there's an unlimited flow of combustion air which will help with the effectiveness of the flue up-draught thus also helping to avoid the potential escape of dangerous carbon monoxide from the stove as the stove's fire burns down.