A twenty litre pail was two thirds filled with dry wood pellets and lit on top. After a few minutes to allow the fire to spread evenly over the surface, the lid and burner were put in place. This extingushes the flame in the can, but it is relit in the burner. During the start up phase the paint on the top portion of the can was blackend. The painted portion corresponds to the depth of the pellet fuel at start up. For the following couple of hours the pellets pyrolysed into charcoal without burning the paint on the can. This test lasted about two hours.