Fire’s food is oxygen, so regulate this and you can control your closed combustion fireplace. More oxygen means more heat output as the combustion processes is accelerated and vice versa.

Closed combustion stoves have a combustion chamber and will have a primary air intake control. Some stoves have a secondary and even tertiary controls which may or may not be adjustable.

Usually the primary control is at the bottom of the stove and secondary at the top. The secondary air intake supplies oxygen to the top part of the combustion chamber for secondary combustion of gasses/volatiles. The secondary air intake also acts as air wash system to keep the glass of the unit clean.

Please refer to your manual for specific instructions.


All oxygen controls fully open. It may also be necessary to leave the door/glass a crack open until the wood has properly caught fire (Few minutes).

Please be aware that leaving the door/glass open for extended periods of time will overheat and damage the fireplace.


 Depending the required heat output the air controls can be opened up or closed down accordingly.

More oxygen – bigger flames, higher kW output, higher temperatures and higher fuel consumption.

Less oxygen – smaller flames, lower kW output, lower temperatures and lower fuel consumption.


Before new wood is added to the combustion chamber – open all oxygen controls fully. Do this by slowly open the door/glass of the unit to prevent smoke from entering the room.

Leave all oxygen controls open until the newly loaded wood is well lit, before the oxygen controls are set lower.


Load the maximum allowed load of wood. Open all air vents and ensure the wood is well lit. Completely close or choke down the primary and if possible, secondary, air intakes.

A slow rolling flame in the top part of the combustion chamber is the optimal result.

Leave a Reply