A convection oven has five major components.Oven enclosure (shell):contains the environment necessary for the curing process, including a support structure, insulated panels, and product opening seals.Heater unit: the second system at work in an oven is the heater unit.The heater generates the energy for curing and beings the distribution of energy.The most of the heater are the burner, supply fan and filters.Supply air system.Recirculated air system, the recirculating system returns oven air to the heater unit so that energy is continually added to the oven. Exhaust air system, every oven must be exhausted, Exhausts create a negative environment so that air seals operate properly  .