Abstract: A blower forces outside air into a heat conductive shell located within a fireplace. A partition separates the shell into inlet and outlet sides, and a baffle causes the air to follow a tortuous path through the inlet side. Heat conductive pipes extending above the shell direct the air between the inlet and outlet sides of the shell. The heated air is distributed within the building through ducts that connect with the outlet side of the shell. The blower forces air to flow through the device at a rate at least as great as the rate of flow through the flue plus the rate of air consumption by the fire.