Abstract: A circulating air building temperature control system includes a pumped air circulation conduit for distributing controlled temperature air throughout the building and collecting return air, and a fireplace for burning solid fuel, the air circulation conduit being positioned about the exterior of the fireplace chamber walls and sealed from the fireplace chamber. An outer housing is also provided to define an outer chamber positioned about the air circulation conduit, and connected to air inlets and outlets to limit the upper temperature of the outer housing wall even in the event of a hot fire and no circulation through the air circulation conduit.

Abstract: A circulating-fluid building heating system, such as a forced air system, is positioned in heat transfer relationship to fireplace chamber-defining walls which sealingly separate the fireplace chamber from the fluid circulation conduit. The fireplace chamber-defining walls have an upper portion which defines wall means which are horizontally extensive and thermally conductive. Accordingly, rising hot gases from a fire in the fireplace chamber impinge the horizontally extensive wall means, for heat exchange with fluid in the circulation conduit. Additionally, solid, transparent, openable and closable doors separate, in closed position, the fireplace chamber from the building interior. Accordingly, a fire in the fireplace chamber may be viewed without removal of large amounts of air from the building interior by means of the fireplace draft.