Because every manufacturer makes a different oven, the recipe says it is placed in the middle of the baking, generally can not adjust the upper and lower fire oven, because the upper and lower fire is a temperature, in order to ensure even heat, so it said in the middle. Most of these ovens are just for home use too.

If it is for commercial use, it is possible to adjust the upper and lower fire, so that it does not matter which is in which layer, just adjust the fire one by one.

Extended information:

If you are baking cookies, you can bake according to your own taste, it is recommended that the cake is placed in the lower layer, baking cookies can be on the upper layer.

Medium-sized ovens usually contain upper, middle and lower heights to choose from, as long as the recipe does not specify the upper and lower heat temperatures, the baking tray in the middle can be; if the upper heat temperature is high and the lower heat temperature is low, unless the upper and lower heat of the oven can be adjusted independently of the temperature, or this time it is usually the upper and lower heat temperatures are divided by two, and then the baking tray can be placed on the upper level, but you need to keep an eye on the surface of the scorched.

The oven is a sealed appliance used to bake food or dry products, divided into household appliances and industrial ovens.

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