Convection ovens are less common in American homes than the standard radiant ovens. However, cooks who prefer quick, uniform results enjoy cooking with a convection oven. The difference between the two is the way each heats food. In a convection oven, hot air is circulated around the food with a fan, cooking it more quickly than a thermal oven. There are advantages and disadvantages to this method.
Convection ovens cook food more quickly than conventional ovens, which are called radiant or thermal ovens. This is because a convection oven uses a fan to move hot air around food, actively transferring heat and causing food to cook more quickly than it would in a conventional oven. Because a conventional oven does not have a fan, hot air is not directed at the food but merely surrounds it. A convection oven cooks food 25 percent more quickly than a conventional oven, saving you time in the kitchen.
A convection oven uses heat more efficiently than a conventional oven, so it requires a lower temperature and a shorter cooking time. A recipe that would be cooked at 350 degrees for an hour in a conventional oven would be cooked at 325 degrees for 45 minutes in a convection oven, saving energy and money.
The position of food in relation to the heating elements of an oven is key factor in cooking results. When you place food on more than one rack in a conventional oven, even multiple batches of the same food, cooking times vary because each rack has different access to the heat. In a convection oven, the fan blows heat evenly, giving uniform results.
Because convection ovens are not standard in homes, they require an adjustment on the part of the cook. Though it is desirable for food to quick more quickly and uniformly, this can be a disadvantage if you are not accustomed to using a convection oven. Recipes are written with a conventional oven in mind, so you must convert temperatures and times to those appropriate for a convection oven to prevent overcooking.
A convection oven saves money in energy, but they are more expensive than standard ovens. Prices for kitchen-sized convection ovens start about $1,500 (as of 2010).