Abstract: A fireplace cap is positioned outside the firebox of the fireplace. The cap has a framework comprised of first and second side members, an upper cross member and a lower damper section. A pair of hinged doors are mounted to this framework. Dampers selectively control the passage of primary combustion air directly to the firebox. A mantel overlies the upper cross member and a secondary air deflector baffle extends downwardly from the underside of the mantel. This baffle, together with the upper cross member, defines a transversely extending secondary air preheating chamber. Preheated air from the chamber is directed by the baffle across the doors prior to passing into the firebox. In one embodiment, secondary air enters the chamber through a space between the mantel and upper cross member. A valve controls the flow of secondary air to this space.

Abstract: A fireplace cap includes a pair of hinged doors supported by a rectangular framework of first and second side rails, a header section, and a damper section. The components forming the framework are formed with flanges positioned at the rear of the cap for reinforcing purposes and to act as heat exchangers, picking up heat from a fire within the fire box of the fireplace. This cap can be easily custom fit to fireplaces having fire boxes of various sizes by selecting appropriate components for the framework. A top piece mounted to the header section may serve as a cooking surface. The doors may include optional glass plates supported for easy removal by angle members mounted to the back side of the doors. A latching mechanism, including eccentrically mounted latching arms, holds the doors tightly closed when latched. The top piece and side rails define sealing material receiving pockets and include retainers for holding sealing material to seal the cap against the front of the fireplace.