What differentiates convection bake from convection roast is basically how the heat gets applied or supplied while the fan is working. In convection bake, the baking process is almost similar to a regular oven.
The device uses heating elements both at the top and bottom parts so as to provide a more uniform heat to the food. The air circulation is minimal to allow the food to cook or bake thoroughly. It’s ideal for making cakes and bread as it ensures you don’t end up with a crunchy shell and an unbaked center.
In convection roast on the other hand, the fan and the broil elements are actively used during the cooking process. The broil elements heat the air while the fun circulates the air around the oven. It circulates the air on the bake as well as the broil elements as needed so as to control the heat.