DEFRA Approved. Output - 5kW. Item Grisedale Wood Stove - 5kW - ECODesign. - 12mm decorative hearth compatible. - 5mm and 8mm steel seam welded stove body construction. Preheated air is drawn into the fire chamber and injected into the path of the gases produced during primary combustion, this reignites the gases resulting in a significantly cleaner and more efficient fire.