Abstract: A method of controlling water heater pilot flame ignition includes receiving, by a controller of a water heater, a user input and controlling a pilot gas valve to start a gas flow to a pilot burner in response to the user input. The method further includes, in response to the user input, controlling, by the controller, an igniter to generate an ignition spark for lighting a pilot flame. The method also includes controlling, by the controller, the pilot gas valve to maintain the gas flow to the pilot burner if the pilot flame is lit.

Abstract: A water heater can include a tank, an inlet line, and an outlet line, where the inlet line provides unheated water to the tank, and where the outlet line draws heated water from the tank for a hot water demand. The water heater can also include a heat pump disposed adjacent to a first portion of the tank, where the heat pump applies heat to transform the unheated water to heated water in the first portion of the tank. The water heater can further include a resistive heating element disposed within a second portion of the tank, where the resistive heating element further applies heat to transform the unheated water to heated water in the second portion of the tank.

Abstract: A water heater can include a tank. The water heater can also include a heat exchanger that includes multiple flue tube segments disposed within the tank, where the flue tube segments include a thermally-conductive material. The heat exchanger can further include a heating system that heats a fluid to create a heated fluid, where the heating system further circulates the heated fluid through the flue tube segments, where the flue tube segments absorb thermal energy from the heated fluid and subsequently dissipate the thermal energy into the tank to convert the unheated water to the heated water. The water heater can also include a controller coupled to the heating system, where the controller operates the heating system outside of a normal heating cycle when the controller determines that condensation has accumulated in the flue tube segments, where operating the heating system outside of the normal heating cycle removes the condensation.

Abstract: The metal tank portion of an electric water heater is protected against corrosion utilizing a corrosion protection system that detects a voltage potential between the sheath portion of a tank water-immersed electric heating element and the tank. In one embodiment of the corrosion protection system the sensed sheath/tank potential is utilized to enable a user of the water heater to accurately gauge the necessity of replacing a sacrificial anode extending into the tank. In another corrosion protection system, the sensed sheath/tank potential is utilized to provide impressed current cathodic protection of the tank and also to prevent dry firing of the electric water heater.

Abstract: A fuel-fired appliance with thermoelectric-powered secondary electric heating has a burner providing hot combustion gasses into a first housing. A second housing containing a fluid receives heat from the combustion gasses in the first housing. A thermoelectric device attaches to a surface of the appliance heated by the combustion gasses and generates a voltage. An electric heating element is in thermal communication with the second housing, and the electric heating element is electrically connected to the thermoelectric device.

Abstract: A water heating system can include a water heater having a tank, an inlet line, and an outlet line, where the inlet line provides unheated water to the tank, and where the outlet line draws heated water from the tank. The water heating system can also include multiple sensing devices, where each sensing device of the plurality of sensing devices measures a parameter associated with the tank. The water heating system can further include a controller communicably coupled to the plurality of sensing devices, where the controller determines an amount of heated water in the tank based on measurements made by the plurality of sensing devices.

Abstract: A water heater includes a leak detection system that is integrated with the water heater. The leak detection system includes a channel that extends circumferentially around the water heater. In one example, the channel is built into the water heater. In another example, the channel is formed by a sensor bracket that is coupled to the water heater. Further, the leak detection system includes a sensor assembly that is configured to detect water that leaks from the water heater. The sensor assembly includes a leak sensor and/or a wicking tube. The wicking tube is disposed around at least a portion of the leak sensor. Further, the wicking tube is disposed in the continuous channel and extends circumferentially along the water heater to create a circumferential area of leak detection around the water heater.

Abstract: 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.

Abstract: A water heating system can include a water heater having a tank, an inlet line, and an outlet line, where the inlet line provides unheated water to the tank, and where the outlet line draws heated water from the tank. The water heating system can also include multiple sensing devices, where each sensing device of the plurality of sensing devices measures a parameter associated with the tank. The water heating system can further include a controller communicably coupled to the plurality of sensing devices, where the controller determines an amount of heated water in the tank based on measurements made by the plurality of sensing devices.

Abstract: A water heater monitoring and notification method includes determining, by a controller of a water heater system, a deviation of a duration of a pre-purge operation from a pre-purge duration average value. The method further includes determining, by the controller of the water heater system, a deviation of a flame current from a flame current average value and determining, by the controller of the water heater system, a deviation of a pulse-width-modulation (PWM) parameter from a PWM parameter average value. The method also includes providing a notification related to a combustion system of the water heater system based on at least the deviation of the duration of the pre-purge operation from the pre-purge duration average value, the deviation of the flame current from the flame current average value, and the deviation of the PWM parameter from the PWM parameter average value.

Abstract: A water heater includes a leak detection system. The leak detection system includes a leak sensor assembly that is disposed in a bottom pan of the water heater. The leak sensor assembly includes a sensor housing that has a sensor channel that is formed therein such that the sensor channel is disposed at an elevation from a base of the bottom pan when the sensor housing is disposed on the base of the bottom pan. Further, the leak sensor assembly includes a leak sensor that is disposed in the sensor channel of the sensor housing. The leak sensor detects water that leaks from the water heater and accumulates in the bottom pan when a level of the water in the bottom pan rises to the elevation of the sensor channel and the leak sensor that is disposed therein.

Abstract: A water treatment device includes a water treatment material contained within a housing of the water treatment device. The incoming water is exposed to the water treatment material to produce treated water. A magnetic field-based or a light-based sensor may determine an amount of the water treatment material remaining in the water treatment device and provide notification.

Abstract: 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.

Abstract: A water heater monitoring and notification method includes determining, by a controller of a water heater system, a deviation of a duration of a pre-purge operation from a pre-purge duration average value. The method further includes determining, by the controller of the water heater system, a deviation of a flame current from a flame current average value and determining, by the controller of the water heater system, a deviation of a pulse-width-modulation (PWM) parameter from a PWM parameter average value. The method also includes providing a notification related to a combustion system of the water heater system based on at least the deviation of the duration of the pre-purge operation from the pre-purge duration average value, the deviation of the flame current from the flame current average value, and the deviation of the PWM parameter from the PWM parameter average value.

Abstract: A water heater includes a leak detection system. The leak detection system includes a leak sensor assembly that is disposed in a bottom pan of the water heater. The leak sensor assembly includes a sensor housing that has a sensor channel that is formed therein such that the sensor channel is disposed at an elevation from a base of the bottom pan when the sensor housing is disposed on the base of the bottom pan. Further, the leak sensor assembly includes a leak sensor that is disposed in the sensor channel of the sensor housing. The leak sensor detects water that leaks from the water heater and accumulates in the bottom pan when a level of the water in the bottom pan rises to the elevation of the sensor channel and the leak sensor that is disposed therein.

Abstract: A water heater can include a tank. The water heater can also include a heat exchanger that includes multiple flue tube segments disposed within the tank, where the flue tube segments include a thermally-conductive material. The heat exchanger can further include a heating system that heats a fluid to create a heated fluid, where the heating system further circulates the heated fluid through the flue tube segments, where the flue tube segments absorb thermal energy from the heated fluid and subsequently dissipate the thermal energy into the tank to convert the unheated water to the heated water. The water heater can also include a controller coupled to the heating system, where the controller operates the heating system outside of a normal heating cycle when the controller determines that condensation has accumulated in the flue tube segments, where operating the heating system outside of the normal heating cycle removes the condensation.

Abstract: In an electric water heater having adjustable set point and differential temperatures, upper and lower heating elements, and associated temperature sensors respectively operative to sense upper and lower tank water temperatures, a specially designed control system is provided for controlling the heating elements. The control system is operative to prevent dry firing of the heating elements by measuring temperatures over time with the temperature sensors.

Abstract: A water heater has a tank and at least one heating element. A switch is disposed in an electric circuit between the heating element and a power source so that, if the switch is in a first state, the circuit is in an electrically conductive state and, if the switch is in a second state, the electric circuit is in an electrically non-conductive state. A controller is in operative communication with the switch and is responsive to a key so that actuation of the controller by the key transitions the switch between the first state and the second state.

Abstract: An enclosure for a water heater can include a cover having at least one body coupling feature and at least one first water heater coupling feature. The enclosure can also include a body detachably coupled to the cover, where the body includes at least one cover coupling feature that couples to the at least one body coupling feature of the cover. The at least one water heater coupling feature can be configured to receive an enclosure coupling feature of the water heater, where the enclosure coupling feature, when received by the at least one water heater coupling feature, secures the body against a tank of the water heater.