Fireplace adapter

Claim 1

A universal fireplace flue adapter assembly for sealably connecting the flue outlet of a heating device to the fireplace chimney flue through a fireplace throat having an existing damper assembly including a damper frame with an opening, the plane of the opening making a given angle with the horizontal up to a maximum angle, and a movable damper element normally adaptable to open or close the opening to the chimney flue, movable to a position out of the way of the opening, comprising an adapter plate having an opening smaller than the damper frame opening, means for sealably securing said adapter plate parallel to and in juxtaposition with the damper frame so that the adapter plate opening is encompassed by and substantially coplanar with the damper frame opening, a curved duct extending through the adapter opening, said curved duct having a lower inlet end below the adapter plate and an upper outlet end extending upwards behind the adapter plate, the angle between the direction of the inlet and outlet ends corresponding to the maximum angle, said curved duct further including a curved transition section between said inlet and outlet ends with a geometry such that the outer surface of said curved duct which intersects said adapter plate opening is substantially congruent to the inner periphery of the opening for any angle made by said existing damper frame, said curved transition section being a hollow section formed by front and back walls and a pair of sidewalls, at least the front wall being curved for allowing angular movement such that when the duct is tilted on the line where the back wall meets the back edge of the opening, the cross section of the curved duct intersected by the plane of the adapter opening continuously matches that of the adapter opening, and means for securing said curved duct in said adapter plate so that the lower inlet end is substantially vertical regardless of the damper frame angle.