Hi, Im sorry Eamonn, I don't understand the question, how do you get ash from an oil burner?, I would have thought you may get a little bit of sooty substance near the burner, but I thought you only got ash from solid fuel, such as wood, coal etc, Derek.

You get a sooty deposit from oil boilers, Derek, and, Eamon, I would not put it anywhere near the garden as it will be toxic due to the hydro-carbons in the soot.