Abstract: A fireplace heat exchanger unit including a forward section disposed outside of the fireplace and a rearward section disposed within the fireplace. The forward section provides upper air inlet openings for admitting cool air into an air inlet chamber and a pair of lower air outlet openings having electric blowers for discharging warmed air from air outlet chambers housing electric blowers. The rearward section is generally U-shaped and provides a duct connection between the inlet and outlet chambers. It is disposed about the heat source and the duct connection provides air heating chambers to warm the air during passage from the inlet to the outlet chambers.