Convection wall ovens are by far the most universal oven design. The ability to cook on each and every rack in the oven at the same time is a huge time saver. "European Style" ovens take this a step further. Fuel types are gas and electric.
These are technically not true convection ovens, rather they are forced convection because they use fans to evenly distribute the heat throughout the entire oven. In conventional built in ovens the temperatures can vary greatly from the bottom to the top.
Conventional ovens are less able to cook in all areas of the oven. In a true convection oven it doesn't matter on which rack you place your food, just as long as there is one inch of space around the food being cooked. Long gone are the days when you have to place the food you want to cook in the center of the oven, and wasting the rest of the space because of heat variations.
Heated air that is forced around foods is more efficient at cooking. The reasons for this is food absorbs heat and therefore lowers the temps in the oven. By moving the air in the oven around it eliminates the cooler areas and evens out the air temp. If the air is not moved mechanically, then hot spots can develop and food can cook unevenly.
You may also care to know that this type of unit is also available in a portable convection oven. It's essentially a big toaster oven with forced convection technology. Maybe a good idea for the small kitchen? Or those who bake only occasionally?
These convection wall ovens are also more expensive than their conventional counterparts. The reasons for this the extra engineering involved in placing fans in the oven. The fans need to be able to take high heat and not fail. To accomplish this more shielding insulation is needed for the motors to be kept at an acceptable operating temperature.
The European Style convection wall oven takes this one step further by using a separate heating element to preheat the air coming out of the fan. These are the most expensive type of convection oven and this style is the most effective at cooking. This type of oven can reduce cooking times by 35 to 40% over a conventional oven.
Because these ovens are so good at cooking in less time the extra costs associated with these ovens can be offset by the energy savings. Of course this depends on how much cooking you do. Over the lifetime of the appliance you may be able to make up the extra cost in energy savings.
These ovens are very good at sealing in juices, therefore your food will be more flavorful. This is accomplished because lower temps can be used to cook foods. Cooking times are also reduced by 25 to 30% in this type oven. If you bake a lot these ovens are the top choice because the cookies and pastries are much flakier.
These ovens are so good at keeping the temps even, when cooking with these ovens it's necessary to lower the cooking temps. There may be a bit of a learning curve with these appliances because the cooking is so much different than the conventional types.
Until you get a good grasp on the differences in cooking times I recommend getting a cook book that deals with true convection ovens, as most cook books deal with conventional ovens. Be sure to check out my page on combination wall ovens as the convection oven is also available in that heating type.
The oven cavity is often smaller in this type oven therefore reducing the amount of air needing to be heated. The smaller size oven is of little concern because you can use all of the oven and not just the center rack.
These convection wall ovens are a great choice for any kitchen and their smaller sizes, 24 to 30 inches, can fit into any kitchen. The smaller kitchens lend themselves to this type of oven if a range is not used.