Abstract: An improved heat exchange system comprising a housing (66) having an upper portion (22), a middle portion (23), and a lower portion (24), a heat exchange conduit (25) transmitting a fluid from a fluid input (26) to a fluid output (27) through the upper zone, the transitional zone and the lower zone, a burner (28) configured and arranged to produce combustion flue gases that can flow through at least a portion of the upper zone, the transitional zone and the lower zone, a baffle (30) disposed in the lower portion of the housing, and a gas flow diverter (40) disposed above the baffle and at least partially in the transitional zone. The gas flow diverter is configured and arranged to divert the flue gas into multiple flow paths.

Abstract: A heat exchange system comprising a housing (66) elongated along a longitudinal axis (x-x) having an upper portion (22) defining an upper zone, a middle portion (23) defining a transitional zone, and a lower portion (24) defining a lower zone, a heat exchange conduit (25) elongated along the longitudinal axis interior to the housing and configured and arranged to transmit a fluid from a fluid input (26) to a fluid output (27) through the upper zone, the transitional zone and the lower zone, a burner (28) configured and arranged to produce combustion flue gases that can flow through at least a portion of the upper zone, the transitional zone and the lower zone, a hot flue gas flow path (35) between the upper zone and the lower zone, a baffle (30) disposed inside of the heat exchange conduit relative to the longitudinal axis and in the lower zone of the lower portion of the housing, and a gas flow diverter (40) disposed inside to the heat exchange conduit relative to the longitudinal axis and above the baffle a

Abstract: A steam boiler (15) comprising a fuel burning device (16) disposed in a combustion chamber and adapted to burn a fuel to form combustion gases (19), a passage (30) extending between a water inlet (20) and a steam outlet (23), the passage having a water space (31) and a steam space (32), a flue passage (33) extending between the combustion chamber and a flue outlet (24) and having a gas heat transfer space (34), a heat exchange element (43) between the gas heat transfer space and the water and steam spaces, the heat exchange element having a gas-side surface (35) that absorbs heat from the combustion gases and an opposed water-side surface (38) that radiates heat, the water-side surface having a first portion (39) adjacent to the water space and a second portion (40) adjacent to the steam space, the gas-side surface having a first portion (36) opposite the water-side first portion and a second portion (37) opposite the water-side second portion, the water-side first portion having a surface area and the water