A water heating system can include a first tank-based water heater having a first inlet line and a first outlet line, where the first inlet line provides unheated water to the first tank, and where the first outlet line draws heated water from the first tank. The system can also include a first tankless water heater having a second outlet line, where the second outlet line of the first tankless water heater provides the heated water to a first heated water demand. The system can also include a first valve that controls an amount of the unheated water flowing through the first inlet line to the first tank-based water heater. The system can further include a controller operatively coupled to the first valve, where the controller controls a position of the first valve based on the first heated water demand and a first capacity of the first tankless water heater.

The disclosed technology includes a gas delivery system for controlling a target gas input rate of a fluid heating device. The system can include a sensor configured to measure a temperature of a gas flowing in a gas flow path, a modulating orifice in fluid communication with the gas flow path, and a motor in mechanical communication with the modulating orifice. The system can further include a controller configured to receive temperature data indicative of the temperature of the gas. The controller can determine a target cross-sectional area of the modulating orifice based at least in part on the target gas input rate and the temperature of the gas and, in response, output a signal to the motor to transition the modulating orifice from a first position to a second position having the target cross-sectional area.

A water heating system can include a first tank-based water heater having a first inlet line and a first outlet line, where the first inlet line provides unheated water to the first tank, and where the first outlet line draws heated water from the first tank. The system can also include a first tankless water heater having a second outlet line, where the second outlet line of the first tankless water heater provides the heated water to a first heated water demand. The system can also include a first valve that controls an amount of the unheated water flowing through the first inlet line to the first tank-based water heater. The system can further include a controller operatively coupled to the first valve, where the controller controls a position of the first valve based on the first heated water demand and a first capacity of the first tankless water heater.

A water heater appliance and a method of configuring or reconfiguring said appliance for connection to one or more external conduits located above or below said appliance is disclosed. The water heater appliance comprises a housing at least partially defining an interior. At least one conduit is positioned within the interior and has a fixable conduit section and a movable conduit section coupled at a joint and movable relative to the fixable conduit section. The joint permits rotation of the movable conduit section about an axis of the joint while remaining coupled to the fixable conduit section. The movable conduit section is movable for being oriented or reoriented for alignment with an opening in an upwardly-facing surface of the housing, or oriented or reoriented for alignment with an opening in a downwardly-facing surface of the housing, for the water heater appliance to be configured for connection to the external conduit.

A water heater appliance and a method of configuring or reconfiguring said appliance for connection to one or more external conduits located above or below said appliance is disclosed. The water heater appliance comprises a housing at least partially defining an interior. At least one conduit is positioned within the interior and has a fixable conduit section and a movable conduit section coupled at a joint and movable relative to the fixable conduit section. The joint permits rotation of the movable conduit section about an axis of the joint while remaining coupled to the fixable conduit section. The movable conduit section is movable for being oriented or reoriented for alignment with an opening in an upwardly-facing surface of the housing, or oriented or reoriented for alignment with an opening in a downwardly-facing surface of the housing, for the water heater appliance to be configured for connection to the external conduit.

A water heater includes a heat exchanger. A controllable three-way proportional valve provides a proportionally controllable flow to the hot water inlet of the heat exchanger and a boiler return water outlet. A mixing tank mixes a cold water and a hot water. The mixing tank provides a time delayed mixed water. A temperature sensor is disposed in or on the mixing tank to measure a temperature of the time delayed mixed water to provide a time delayed mixed water temperature. A feedforward control process running on a processor adjusts a proportional operating position of the controllable three-way proportional valve to regulate a temperature of hot water at the hx domestic hot water outlet based on the temperature of the time delayed mixed water temperature. A method for controlling a hot water temperature of a water heater a water heater using a flowmeter based feedforward control are also described.

A water heater dip tube includes an elongated body having an inlet end and an outlet end. An inner volume is arranged within the elongated body. An anti-siphon orifice is arranged along the elongated body proximate the inlet end. The anti-siphon orifice extends through a wall of the elongated body. The dip tube further includes an elastomeric membrane secured to the elongated body. The elastomeric membrane is arranged in the vicinity of the anti-siphon orifice. The elastomeric membrane is operable to block fluid flow through the anti-siphon orifice when a pressure at the inlet end is greater than a pressure at the exterior of the dip tube adjacent to the anti-siphon orifice, and to allow fluid flow through the anti-siphon orifice when a pressure at the inlet end is less than a pressure at the exterior of the dip tube adjacent to the anti-siphon orifice.

The present application relates to a water system that includes a prefabricated fitting tee for use with a water heater. The prefabricated fitting tee includes a fitting tee body that has a first port, a second port, and a third port. The first and third ports can be aligned along a main axis and the second port can be aligned along an axis angled relative to the main axis. The fitting tee body defines an interior passageway that is in fluid communication with the first, second, and third ports. One of the first and second ports is configured for connecting to a water inlet conduit for supplying water from an external source, the other one of the first and second ports is configured for connecting to a pressure relief or pressure absorption mechanism. The prefabricated fitting tee does not include a check valve for preventing flow from the first port to the third port and no check valve for preventing flow from the second port to the third port. A swivel nut can be rotatably mounted at the third port of the prefabricated fitting tee to provide an interconnection to the water heater. When the swivel nut is in a first condition, the swivel nut allows the prefabricated fitting tee to be rotated relative to the water heater about the main axis to allow a rotational orientation of the second port to be established. When the swivel nut is in a second condition, the swivel nut clamps the prefabricated fitting tee in the established rotational orientation.

The present application relates to a water system that includes a prefabricated fitting tee for use with a water heater. The prefabricated fitting tee includes a fitting tee body that has a first port, a second port, and a third port. The first and third ports can be aligned along a main axis and the second port can be aligned along an axis angled relative to the main axis. The fitting tee body defines an interior passageway that is in fluid communication with the first, second, and third ports. One of the first and second ports is configured for connecting to a water inlet conduit for supplying water from an external source, the other one of the first and second ports is configured for connecting to a pressure relief or pressure absorption mechanism. The prefabricated fitting tee does not include a check valve for preventing flow from the first port to the third port and no check valve for preventing flow from the second port to the third port. A swivel nut can be rotatably mounted at the third port of the prefabricated fitting tee to provide an interconnection to the water heater. When the swivel nut is in a first condition, the swivel nut allows the prefabricated fitting tee to be rotated relative to the water heater about the main axis to allow a rotational orientation of the second port to be established. When the swivel nut is in a second condition, the swivel nut clamps the prefabricated fitting tee in the established rotational orientation.

A water heater system includes a water tank and a flow-through heating assembly. The water tank contains heated water. The flow-through heating assembly may extend into the water tank and heats water as water is passed through an interior channel of the flow-through heating assembly. In one embodiment, the flow through heater assembly is a thermosiphonic heater having a hollow body and a heating element extending therein such that an annular recess is defined between an interior surface of the hollow body and the external surface of the heating element.