Thanks guys.
Peter. The output of our small log burner was based on the calorific value of burning Beech.
It's a small Scandinavian model (3 to 4 KW.), but it is fine for what we need.
I have found, however, that moderation is needed when burning offcuts of wood like Iroko!
Here's an old English poem, relating to open fires.
Hope you can see this.
This forum seems to have gone very slow for me tonight.
Every thing else seems OK.
Neil