An apparatus includes a high-pressure tank, a controller, a valve, controlled by the controller, and a heater.

A flue baffle for a water heater comprises a plurality of holes along a length of the baffle and a plurality of bent blades along the length of the baffle, where each hole of the plurality of holes is adjacent to a bent blade of the plurality of bent blades. The holes are configured to permit flue gas to pass through the holes. The bent blades can have an alternating pattern where a first bent blade extends from one side of the baffle and the next bent blade extends from an opposite side of the baffle. A press tool for forming the baffle comprises a piercing tool for forming the plurality of holes and a lance and fold die for forming the bent blades.

A draft inducer blower assembly includes a blower having a fan, a dilution air intake passage, an exhaust gas intake passage, and a discharge passage. The blower is configured to operatively connect to a heater system in a manner to facilitate flow of combustion air into a combustion chamber and to draw dilution air into the blower and to mix the dilution air with the exhaust gases and to facilitate flow of the mixed air and exhaust gases through the vent. The dilution air intake passage is positionable in at least a low flow configuration and a high flow configuration. The dilution air intake passage is more restrictive of intake of dilution air in the low flow configuration than in the high flow configuration.

A boiler system having a generally cylindrical housing or shell includes a main or fire tube with a furnace or combustion chamber extending longitudinally near the bottom of the housing and a burner to accomplish combustion within the combustion chamber. The combustion chamber opens at its rear end to furnace tube sheet, and to a first set of tubes extending longitudinally of the boiler. The first set of tubes extends to and through the rear tube sheet of the boiler to a turnaround space, which transitions to a second set of tubes located above the combustion chamber and first set of tubes to generally span a length extending from the rear tube sheet of the boiler to the front tube sheet. The boiler system as disclosed has a reduced size while maintaining efficiency in steam and hot water applications.

A heat pump boiler is disclosed. The heat pump boiler includes a compressor. The heat pump boiler further includes an exterior heat exchanger that is configured to transfer heat between refrigerant and exterior air. The heat pump boiler further includes an interior heat exchanger that is configured to transfer heat between refrigerant and water. The heat pump boiler further includes a channel change valve that is configured to provide refrigerant compressed by the compressor to the exterior heat exchanger or the interior heat exchanger. The heat pump boiler further includes a first boiler heat exchanger that is configured to heat water that has passed through the interior heat exchanger from heat generated through combustion. The heat pump boiler further includes a second boiler heat exchanger that is configured to transfer heat between refrigerant and gas discharged from the first boiler heat exchanger.

An apparatus includes a high-pressure tank, a controller, a valve, controlled by the controller, and a heater.

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 base 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 and the base are non-adjustably fixed relative to each other. The exhaust volute has a cut-off at a cut-off angle relative to the rotation axis. The cut-off angle extends at an angle that is no more than twenty degrees positive from horizontal. The exhaust volute has an exhaust outlet passageway that extends to an exhaust port. The exhaust outlet passageway extends beneath the cut-off before reaching the exhaust port.

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 base 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 and the base are non-adjustably fixed relative to each other. 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.

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 base 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.

A flue baffle for a water heater comprises a plurality of holes along a length of the baffle and a plurality of bent blades along the length of the baffle, where each hole of the plurality of holes is adjacent to a bent blade of the plurality of bent blades. The holes are configured to permit flue gas to pass through the holes. The bent blades can have an alternating pattern where a first bent blade extends from one side of the baffle and the next bent blade extends from an opposite side of the baffle. A press tool for forming the baffle comprises a piercing tool for forming the plurality of holes and a lance and fold die for forming the bent blades.