Abstract: Disclosed is a heat exchanger having an economizer configured as a ring of tubes in a periphery of the heat exchanger. The heat exchanger includes a cylindrical flue collector and a manifold at either end of the cylindrical flue collector. The manifold has a plurality of chambers. The manifold can be made of steel or plastic and governs fluid flow rate and direction within a ring of tubes. At least two rings of heat exchanging tubes, an outer ring and an inner ring, are within the cylindrical flue collector. The rings of tubes are concentric with respect to each other.

Abstract: A condensing fuel-fired appliance has a condensate trap that includes a trap body; a float; a flue gas inlet port for the introduction of flue gas into the interior region of the trap body; a condensate outlet port for the discharge of condensate from the interior region; and a flue gas outlet port for the discharge of flue gas from the interior region of the trap body. The float is configured to move in response to condensate collected in the interior region of the trap body to a position to substantially block the discharge of flue gas from the interior region through the flue gas outlet port. The float is also configured to move to a position to substantially block the discharge of flue gas from the interior region through the condensate outlet port when there is little or no condensate in the interior region of the trap body.

Abstract: A drain system is configured to collect condensate from flue gas generated by a condensing fuel-fired appliance. The drain system includes a drain body defining an inlet positioned to receive condensate in the drain body, a drain opening positioned to deliver condensate from the drain body, a passage extending between the inlet and the drain opening, and a seat surface disposed within the passage. A float moves within the passage of the drain body at a location between the inlet of the drain body and the seat surface of the drain body. The float moves to a position contacting the seat surface defined by the drain body to block the flow of flue gas through the passage of the drain body when there is little or no condensate in the passage. A neutralizing agent is positioned along the passage of the drain body for contact with condensate in the passage.

Abstract: A condensing fuel-fired appliance has a condensate trap that includes a trap body; a float; a flue gas inlet port for the introduction of flue gas into the interior region of the trap body; a condensate outlet port for the discharge of condensate from the interior region; and a flue gas outlet port for the discharge of flue gas from the interior region of the trap body. The float is configured to move in response to condensate collected in the interior region of the trap body to a position to substantially block the discharge of flue gas from the interior region through the flue gas outlet port. The float is also configured to move to a position to substantially block the discharge of flue gas from the interior region through the condensate outlet port when there is little or no condensate in the interior region of the trap body.