An electric water heating apparatus includes a first electric water heater having a first tank adapted to hold a quantity of water and a first electric heating structure disposed within the first tank. The electric water heating apparatus further includes a second electric water heater having a second tank adapted to hold a quantity of water; and a second electric heating structure disposed within the second tank. The electric water heating apparatus further includes a control unit that is in electrical communication with the first electric heating structure and second electric heating structure, the control unit configured to prevent both the first electric heating structure and the second electric heating structure from being simultaneously operable.

A controller performs a first operation in which a heat source device directly or indirectly heats water in a first channel of a heat exchanger and a second operation in which the heat source device directly or indirectly cools the water in the first channel of the heat exchanger after the first operation ends.

A hybrid water heater incudes a storage tank, a first temperature sensor, a tankless heater fluidly coupled to the storage tank, and a controller configured to determine a target output temperature range for the tankless heater based on a temperature setpoint, measure a temperature of hot water stored in an upper portion of the storage tank using the first temperature sensor, determine whether the measured temperature of the hot water is less than a first minimum temperature setpoint, generate an adjusted target output temperature range for the tankless heater based on a determination that the measured temperature is less than the first minimum temperature by increasing a value of both the lower threshold and the upper threshold, and control the tankless heater to produce the heated water according to the adjusted target output temperature range.

A method of heating water in a water storage tank. The method includes: selecting an outlet port and an inlet port from at least three ports located in the tank at different heights along a vertical direction. The outlet port is below the inlet port. The method further includes extracting water from the outlet port, supplying the extracted water to an external heat exchanger configured for heating the extracted water, and delivering heated water from the heat exchanger to the selected inlet port.

A preheater for a compressor that is capable of heating a lubricant oil efficiently with smaller power is provided. A preheater for a compressor includes: a capacitive oil surface sensor that is provided at a compressor used in a refrigerating cycle, and detects an oil surface of a lubricant oil A in the compressor; and a power supply unit that applies high-frequency voltage to the oil surface sensor.

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.

The present disclosure addresses systems, media, and methods of predicting a remaining useful life of a water heater storage tank included in a water heating system. To predict the remaining useful life of the water heater storage tank, algorithmic calibration processes can be used to determine an anodic current range for a corrosive current flowing between the water heater storage tank and an anode rod inserted into the water heater storage tank. Respective values for the corrosive current can be measured, and a rate of reduction of the corrosive current can be calculated based on the respective measured values for the corrosive current. An estimate of a remaining useful life of the water heater storage tank can be made, and an alert indicative thereof can be transmitted based, at least in part, on the calculated rate of reduction of the corrosive current.

The disclosure relates to a device that saves water, energy, and money and may record the savings with a software analytics dashboard. The device allows cold water to flow out when the shower is first turned on and slows or shuts water flow once the water is heated and the shower is unoccupied. After the presence of the user is detected, the shower flow may resume.

The invention discloses a boiling water heater, which includes a barrel shape internal tank body, a water inlet pipe, a water outlet pipe and a exhaust pipe, the upper end of the tank body, fixedly and hermetically connect to the first upper cover, the first upper cover is fixedly and hermetically connected to the second upper cover. One cavity is formed between the first and second upper covers, water inlet pipe passes through the second upper cover. An exhaust hole is set on the inner wall of water inlet pipe to connect to the cavity, a separation plate extended to the middle which is above the exhaust hole on water inlet pipe's internal wall. The invention has the characteristics of convenient installation and disassembly, convenient cleaning, and can ensure the quality of water flows out, and the production cost is low, and very safe for use.

A system includes a cold water supply, a water heater, a mixing valve, and one or more water use fixtures. The water heater includes a tank, a first temperature sensor configured to output a first temperature signal indicative of a water temperature of water in the tank, a heating device, and a water heater controller configured to control the water heater based on the first temperature signal and an operating temperature setting. The mixing valve outputs a mixed water flow, which is a combination of a hot water flow and a cold water flow, to the water use fixtures. A second temperature sensor outputs a second temperature signal indicative of a water flow temperature of the mixed water flow or the hot water flow, and a system controller selectively deactivates the water heater based on the second temperature signal.