A heat exchanger for a water heater having a burner includes a tube extending longitudinally along a centerline from a first end adjacent the burner to a second end. The tube defines a passage. Strips extend within the passage and are arranged about the centerline. Each strip includes a base and fins extending from opposite sides of the base such that flue gases from the burner flow from the first end to the second end of the outer tube and in channels between the fins.

The present invention relates to a heat exchanger pipe enabling heat exchange between fluid flowing through the pipe and fluid existing outside the pipe, and a method of manufacturing the heat exchanger pipe. In particular, the present invention relates to a heat exchanger pipe that improves a heat exchange rate by making flow of fluid through the pipe more active and increasing a contact amount, that has an improved contact characteristic and a sealing characteristic between an outer pipe and an insert inserted in the outer pipe in the process of manufacturing, and that is easily manufactured; and a method of manufacturing the heat exchanger pipe.

A furnace for a heating, ventilation, and/or air conditioning (HVAC) system includes a heat exchanger tube including a tube inlet and a tube outlet, such that the heat exchanger tube is configured to receive combustion products via the tube inlet, circulate the combustion products through the heat exchanger tube, and discharge the combustion products via the tube outlet. Additionally, the furnace includes a collector box coupled to the heat exchanger tube and having a cavity configured to receive the combustion products via the tube outlet. The furnace includes a diverter plate disposed within the cavity, where the diverter plate overlaps the tube outlet to disperse the combustion products received via the tube outlet throughout the collector box.

A biomass heating system for burning fuel in the form of pellets and/or wood chips is disclosed, the system comprising the following: a boiler with a combustion device, a heat exchanger with a plurality of boiler tubes, wherein the combustion device comprises: a combustion chamber with a rotating grate, with a primary combustion zone and with a secondary combustion zone; wherein the primary combustion zone is enclosed by a plurality of combustion chamber bricks laterally and by the rotating grate from below; wherein a plurality of secondary air nozzles is provided in the combustion chamber bricks; wherein the primary combustion zone and the secondary combustion zone are separated at the level of the secondary air nozzles; wherein the secondary combustion zone of the combustion chamber is fluidically connected to an inlet of the heat exchanger.

A rotating grate for a biomass heating system is disclosed, the grate comprising: at least one rotating grate element; at least one bearing axle, by means of which the rotating grate element is rotatably mounted; at least one cleaning device attached to one of the rotating grate elements, wherein the cleaning device comprises a mass element movable relative to the rotating grate element; wherein the cleaning device is arranged in such a way that, upon rotation of the rotating grate element, an acceleration movement of the mass element is initiated so that the cleaning device exerts a knocking effect on the rotating grate element in order to clean the rotating grate element.

A biomass heating system for firing fuel in the form of pellets and/or wood chips is disclosed, comprising: a boiler with a combustion device; a heat exchanger with an inlet and an outlet; wherein the combustion device comprises a combustion chamber with a primary combustion zone and with a secondary combustion zone provided downstream thereof; the combustion device having a rotating grate on which the fuel can be burned; the secondary combustion zone of the combustion chamber being fluidically connected to the inlet of the heat exchanger the primary combustion zone being laterally enclosed by a plurality of combustion chamber bricks.

A water heater includes an outer casing defining a longitudinal axis, an axial direction being defined as extending along the longitudinal axis. The water heater further includes a combustor for production of hot flue gases, a primary heat exchanger including a tube positioned within the outer casing, and a secondary heat exchanger including a plurality of plates coupled together by brazing to form a brazed plate heat exchanger. The secondary heat exchanger includes a first set of passages defined between the plates, and a second set of passages defined between the plates and alternating with the first set of passages in the axial direction. The primary and secondary heat exchangers are in fluid communication such that the flue gases flow through the second set of passages before being exhausted, and water to be heated flows through the first set of passages to a delivery point for use upon demand.

A heat exchanger for a water heater having a burner includes a tube extending longitudinally along a centerline from a first end adjacent the burner to a second end. The tube defines a passage. Strips extend within the passage and are arranged about the centerline. Each strip includes a base and fins extending from opposite sides of the base such that flue gases from the burner flow from the first end to the second end of the outer tube and in channels between the fins.

A furnace for a heating, ventilation, and/or air conditioning (HVAC) system includes a heat exchanger tube including a tube inlet and a tube outlet, such that the heat exchanger tube is configured to receive combustion products via the tube inlet, circulate the combustion products through the heat exchanger tube, and discharge the combustion products via the tube outlet. Additionally, the furnace includes a collector box coupled to the heat exchanger tube and having a cavity configured to receive the combustion products via the tube outlet. The furnace includes a diverter plate disposed within the cavity, where the diverter plate overlaps the tube outlet to disperse the combustion products received via the tube outlet throughout the collector box.

A draft inducer blower assembly for use with a water heater has a housing, a motor, and a fan. The housing has an exhaust volute surrounding the fan and a base adapted to be mounted atop a water heater. The housing has an inlet port adapted to receive exhaust gas from the water heater. The fan is connected to the motor for rotation about a rotation axis. The exhaust volute has a cut-off at a cut-off angle relative to the rotation axis. The exhaust volute has an exhaust outlet passageway that extends to an exhaust port. The exhaust port is lower than the top of the exhaust volute.