With all stoves air comes in two flavours. Primary air, which feeds the bed of the fire, and secondary air feeds the flames above it.   Nearly all the energy from wood comes from burning gases released when it is  heated – which means that secondary air is much more important than primary.   There are some golden rules namely:

• Never completely close the secondary air vent. Never (I really mean it).   It’s the easiest way to create soot and tar and completely coat the glass on   the front of your stove with gunk (a technical term).

• Don’t leave the stove door open, unless you have been specifically   instructed to by the manual when lighting the fire. You are crippling your   stove’s efficiency and allowing all the lovely warm air in the room to shoot   off straight up the chimney.

• Remember you’re always looking for a hot, fast burn, as this will be the   cleanest, most efficient way of running the stove. A small hot fire is much   more efficient than a large slow-burning one.