A convection oven includes a convection fan assembly and a trough assembly that surrounds a portion of the heating element(s) of the convection fan assembly. Fluid in the trough assembly is heated and turned into steam by the heating element(s) and blown into the cooking cavity of the convection oven by the convection fan of the convection fan assembly. The steam in the cooking cavity provides moisture to the items that are being cooked and/or heated in the cooking cavity.