A method of operating a water heater, the method including determining a predicted variation of a hot water consumption rate variable over a future time period and calculating a total required operating time of the water heater over that time period. The method further includes determining multiple possible operating profiles of the water heater that provide the total required operating time, and calculating a minimum hot water reserve for each profile. One of the profiles is selected based at least partially on that profile providing a minimum hot water reserve that is not less than a predetermined desired reserve capacity and the water heater is operated over the time period using that profile. The selected profile may be the profile that is calculated to have the lowest operational cost.

A method of operating a water heater, the method including determining a predicted variation of a hot water consumption rate variable over a future time period and calculating a total required operating time of the water heater over that time period. The method further includes determining multiple possible operating profiles of the water heater that provide the total required operating time, and calculating a minimum hot water reserve for each profile. One of the profiles is selected based at least partially on that profile providing a minimum hot water reserve that is not less than a predetermined desired reserve capacity and the water heater is operated over the time period using that profile. The selected profile may be the profile that is calculated to have the lowest operational cost.

A system and approach for developing a periodic water usage profile and demand for controlling a water heater. A mode may be selected for demand for a certain amount of water of a particular temperature range to be available for use from the water heater. Data on hot water usage may be collected and the usage profile and demand may be calculated from the data. The water heater may be programmed to operate in a certain fashion based on the usage profile and demand. A control knob may be on the water heater control to select a particular demand. Control of the water heater may be operated from a remote device connected in a wireless or wired fashion. An optimization program may be implemented in the control of the water heater for achieving one or more beneficial goals related to water heater performance and hot water production.

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.

Disclosed are system 100 and method of energy efficient hot and cold water management. The system 100 comprises: a control unit 101 for dynamically controlling the functioning of the system 100; at least a water storage tank 102 with at least one of a water level sensor, at least a heating element 1021, at least a temperature sensor 1022 or any combination thereof; at least an auxiliary water storage tank 103 with at least one of a water level sensor, at least a temperature sensor 1032; at least a water mixer unit 105 having at least a temperature sensor 1051; a user interface unit 1012 for controlling and monitoring different parameters including temperature, water level, opening and closing of valves 108 and 109; and a power supply with power backup unit 104 for providing basic power for proper functioning of the system 100.

Disclosed are system 100 and method of energy efficient hot and cold water management. The system 100 comprises: a control unit 101 for dynamically controlling the functioning of the system 100; at least a water storage tank 102 with at least one of a water level sensor, at least a heating element 1021, at least a temperature sensor 1022 or any combination thereof; at least an auxiliary water storage tank 103 with at least one of a water level sensor, at least a temperature sensor 1032; at least a water mixer unit 105 having at least a temperature sensor 1051; a user interface unit 1012 for controlling and monitoring different parameters including temperature, water level, opening and closing of valves 108 and 109; and a power supply with power backup unit 104 for providing basic power for proper functioning of the system 100.

The disclosed technology includes an on-demand water heater which uses an electric heat source to heat the water. The on-demand water heater can have a low fluid capacity heating chamber which has an inlet and an outlet, an electric heat source for heating the water, and a controller to control the electric heat source and maintain the temperature of the water at a predetermined temperature setting. The on-demand water heater can be powered by a direct current power source. The on-demand water heater can also utilize a solar thermal system to provide additional heat to the water.

A computer-implemented method monitors and/or controls domestic hot water production and/or distribution. The method includes detecting at least two real temperatures of a fluid stored in a heat storage tank at two different positions along a height of the heat storage tank at least at points in time, and acquiring a temperature distribution pattern of heat stored in the heat storage tank and/or corresponding heat distribution pattern data by applying a temperature-distribution-pattern-algorithm to the detected real temperatures detected at the points in time. The fluid is sanitary hot water, and the heat storage tank is a pressurized tank. A computer may carry out the method. The computer may be part of a system. A computer program may include instructions to cause the controller of to execute the method. The computer program may be stored on a computer-readable medium.

A burner appliance is disclosed. The burner appliance includes a byproduct sensor in an exhaust flue and/or a barometric pressure sensor to detect an environmental pressure at the burner appliance. By calculating concentrations of combustion byproducts in the exhaust with the byproduct sensor, a controller can adjust blower speed and/or fuel rate to modify combustion efficiency. By calculating the environmental pressure at the burner with the barometric pressure sensor, the controller can adjust blower speed and/or fuel rate to modify combustion efficiency. The barometric-pressure data can also be used to adjust blower speed control bands, thereby calibrating the control bands based on environmental pressure. The environmental pressure can be indicative of altitude and/or weather conditions. Methods of operating said burner appliance are also disclosed.

The disclosed technology includes a system and method of preventing short cycling in a water heater. The system can include a burner, a temperature sensor, and a controller. The controller can be configured to perform several steps to determine whether to turn on a burner and whether to increment a temperature offset value based on the amount of time that has elapsed since the last time the burner was on.