Various foods will produce different degrees of soot during the heating process. These soots will carbonize on the high temperature metal surface. If the processed food contains too much fat, a large amount of heavy liquid grease will accumulate on the surface of each part in the furnace. . The grease is not cleaned for a long time, which affects the precise control of the temperature and speed of the oven, and the introduction of fuel grease; a reasonable cleaning frequency is established according to the usage.