A method for identifying an electric water heater having excessive and abnormal electricity consumption for detecting inefficiency or even a malfunction comprising the following steps: The present invention provides a method for automatic detection of inefficient household heater within a group of monitored households, implemented by a server module and a plurality of household client modules, wherein each of said a server module and plurality of household client modules comprising one or more processors, operatively coupled to non-transitory computer readable storage devices, on which are stored modules of instruction code, wherein execution of said instruction code by said one or more processors implements the following actions: acquiring data relating to each monitored household, including at least part of: environmental conditions, power consumption of each water heater, household profile parameters, and household residents' profile parameters; detect events wherein the water heater's power consumption (P) surpasses a predefined threshold (Pth), and henceforth label said detected events as “water heater activation” events; For each house (i) in the training set, and per each consumption day (d), define a binary label L.sub.id. Said label marks the water heater's activity as either ‘Normal’ or ‘Abnormal’ per house i and day d. Initialize all labels as ‘normal training a machine learning algorithm, to create at least one classification model, wherein all monitored households are classified according to said acquired data and parameters; and Using the Activation Events Classification Model after the training stage, to predict the binary label, L.sub.id, or number activation per day that a specific household (i), from beyond the household training set has surpassed a predefined number of water heater activation events (n) within a day.

A hot water supply device including an inlet pipe, an outlet pipe, a burner unit, a heat exchanger, an exhaust aperture, a first temperature sensor detecting a measured exhaust temperature of the exhaust gas, a second temperature sensor detecting a water temperature of water entering the inlet pipe, and a processor. The processor is configured to obtain an error between the measured exhaust temperature and an estimated exhaust temperature, and detects that scale clogging has occurred inside the heat exchange tubing based on an index which is generated using the error between the measured exhaust temperature and the estimated exhaust temperature. The estimated exhaust temperature is a first predetermined value that is determined using a numerical equation which has at least the water temperature of water entering the inlet pipe and a scale number of the hot water supply device as variables of the numerical equation.

Hot water heating system comprising one or more water heaters with at least one water heating mechanism, and a heating-control storage tank generally configured to store heated water in a temperature stratified manner where hotter water tends to be separated from cold water. The heating-control storage tank can receive thermal energy or hot water from the water heater, send thermal energy or water to the water heater as its makeup water, and provide hot water directly to end users. The water heater may or may not be used to provide hot water to end users. The system is electronically controlled using a processor, various sensors, a recirculation pump, and electronically actuated valves. Depending on hot water needs and energy costs, the system controls water heating schedule and amount of hot water stored in the heating-control storage tank by changing system operation modes to minimize energy costs while providing reliable service.

A solar thermal assisted water heating system includes a thermal collector comprising a plurality of fluid channels configured to collect heat from a surface of a photovoltaic module, a drain-back tank coupled to the thermal collector, a first pump coupled to the drain-back tank and configured to pump fluid from the drain-back tank to the thermal collector, a first heat exchanger configured to receive fluid from the thermal collector, a heat pump coupled to the first heat exchanger and configured to remove heat from the fluid and heat water with the removed heat, and a controller configured to control the first pump and heat pump. The system may include a photovoltaic module and a hot water tank. These systems improve the efficiency of water heating, and the drain-back tank may serve as a thermal battery that stores heat and provides the stored heat when environmental temperatures decrease.

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for metering water are disclosed. In one aspect, a method includes the actions of receiving, from a first meter that is connected to a first pipe, first audio data collected during a time period and first temperature data collected during the time period. The actions further include receiving, from a second meter that is connected to a second pipe, second audio data collected during the time period and second temperature data collected during the time period. The actions further include, based on the first audio data, the first temperature data, the second audio data, and the second temperature data, determining a first amount of material that has flowed through the first pipe during the time period relative to a second amount of material that has flowed through the second pipe.

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.

According to an aspect of the present disclosure, there is disclosed a method of determining the use of hot water performed in a system including a water heater and an air handler. The method includes: sensing a temperature of influent flowing into the water heater; sensing a temperature of effluent flowing out of the air handler; calculating a temperature difference between the temperature of the influent and the temperature of the effluent; and determining whether hot water is used by calculating whether the temperature difference is greater than a predetermined value.

A water heating system can include a water heater having a tank, and a first temperature sensor disposed toward a top end of the tank to measure a first temperature and a second temperature sensor disposed toward a bottom end of the tank to measure a second temperature. The water heating system can further include a controller communicably coupled to the first temperature sensor and the second temperature sensor, where the controller determines an amount of heated water in the tank based on a plurality of algorithms and measurements made by the first and second temperature sensors. The plurality of algorithms solves for at least one calculated temperature for at least one point between a first location of the first temperature sensor and a second location of the second temperature sensor, where the at least one calculated temperature is used to determine the amount of heated water in the tank.

An apparatus and method for heating water using a tank or a tankless water heater with improved electronic control. The improved electronic control may include voice and Wi-Fi control of the water heater to allow for remote control of the water heater including through a remote server or cloud server.

A water heating system can include a water heater having a tank, and a first temperature sensor disposed toward a top end of the tank to measure a first temperature and a second temperature sensor disposed toward a bottom end of the tank to measure a second temperature. The water heating system can further include a controller communicably coupled to the first temperature sensor and the second temperature sensor, where the controller determines an amount of heated water in the tank based on a plurality of algorithms and measurements made by the first and second temperature sensors. The plurality of algorithms solves for at least one calculated temperature for at least one point between a first location of the first temperature sensor and a second location of the second temperature sensor, where the at least one calculated temperature is used to determine the amount of heated water in the tank.