Abstract: An apparatus for heating, ventilation and/or air conditioning of an interior space includes a heat exchanger core and a heating/cooling device in fluid connection with the heat exchanger core. A recirculation port is arranged between a supply air chamber and an outside air chamber. A damper is adapted to move between a first position in which the damper blocks the recirculation port and a second position in which the recirculation port is unblocked. When the damper is in the second position, at least a portion of supply air is guided to flow from the supply air chamber through the outside air chamber to the heat exchanger core so as to defrost the heat exchanger core.

Abstract: An apparatus for heating, ventilation and/or air conditioning of an interior space includes a heat exchanger core and a heating/cooling device in fluid connection with the heat exchanger core. A recirculation port is arranged between a supply air chamber and an outside air chamber. A damper is adapted to move between a first position in which the damper blocks the recirculation port and a second position in which the recirculation port is unblocked. When the damper is in the second position, at least a portion of supply air is guided to flow from the supply air chamber through the outside air chamber to the heat exchanger core so as to defrost the heat exchanger core.

Abstract: A boiler that enhances the efficiency of the use of heated gas streams to generate steam is provided. The boiler includes a lower drum, an upper drum, a plurality of conduits adapted to transfer heated fluid from the lower drum to the upper drum, a combustion chamber, and a series of heat transfer chambers adapted to receive combustion gases from the combustion chamber. The first of the heat transfer chambers is positioned above the second heat transfer chamber and receives the heated gas from the combustion chamber prior to the second heat transfer chamber. A method of operating the boiler is also provided. Though aspects of the invention are applicable to package boilers, other aspects of the invention are applicable for use in residential, commercial, or industrial settings.

Abstract: A boiler that enhances the efficiency of the use of heated gas streams to generate steam is provided. The boiler includes a lower drum, an upper drum, a plurality of conduits adapted to transfer heated fluid from the lower drum to the upper drum, a combustion chamber, and a series of heat transfer chambers adapted to receive combustion gases from the combustion chamber. The first of the heat transfer chambers is positioned above the second heat transfer chamber and receives the heated gas from the combustion chamber prior to the second heat transfer chamber. A method of operating the boiler is also provided. Though aspects of the invention are applicable to package boilers, other aspects of the invention are applicable for use in residential, commercial, or industrial settings.

Abstract: A boiler is described comprising a housing with a flue gas inlet for receiving a hot gas flame and an outlet for venting a hot gas produced by the hot gas flame, and a tube assembly mounted within the housing. The tube assembly comprises a lower manifold for receiving a liquid, an upper manifold for receiving a heated version of the liquid; and, a plurality of tubes disposed between the lower and upper manifolds. Each tube is shaped to provide a hot gas pathway that travels in a parallel fashion along at least a lower portion of the longitudinal extent of each tube in the tube assembly to the outlet, whereby the liquid introduced into the lower manifold travels in the plurality of tubes and receives heat from the hot gas along the extent of the hot gas pathway.

Abstract: A boiler is described comprising a housing with a flue gas inlet for receiving a hot gas flame and an outlet for venting a hot gas produced by the hot gas flame, and a tube assembly mounted within the housing. The tube assembly comprises a lower manifold for receiving a liquid, an upper manifold for receiving a heated version of the liquid; and, a plurality of tubes disposed between the lower and upper manifolds. Each tube is shaped to provide a hot gas pathway that travels in a parallel fashion along at least a lower portion of the longitudinal extent of each tube in the tube assembly to the outlet, whereby the liquid introduced into the lower manifold travels in the plurality of tubes and receives heat from the hot gas along the extent of the hot gas pathway.