A zero pressure drop water heating system comprising a cold side conductor having a receiving end and a closed end; a hot side conductor having an exit end and a closed end; a pump; a bypass conductor having a first end, a second end and a bypass valve, wherein the first end is adapted to the receiving end and the second end is adapted to the exit end; at least one heat exchanger having a flow valve; a heat exchanger inlet temperature sensor disposed on the inlet of one of the at least one heat exchanger; an outlet temperature sensor disposed at an outlet of the at least one heat exchanger closest to the exit end; a system outlet temperature sensor disposed on the exit end and a system inlet temperature sensor disposed on the receiving end.

The water heater may be configured to execute a normal operation in which a heating means is continuously operated in an ON state in a case where a required heat quantity is greater than or equal to a minimum heat quantity. The water heater may be configured to execute an intermittent operation in which the heating means is alternately and repeatedly operated in the ON state and an OFF state repeatedly in a case where the required heat quantity is less than the minimum heat quantity. The water heater may be configured to change a distribution ratio of a flow control mechanism in the normal operation and in the intermittent operation. An operating speed of the flow control mechanism in the intermittent operation may be faster than an operating speed of the flow control mechanism in the normal operation.

A water heater system and method of operating such a system are disclosed herein. In an example embodiment, the water heater system includes a heat exchanger. a heat source inlet by which heated heating fluid can be provided to the heat exchanger, a heat source outlet by which cooled heating fluid can be communicated from the heat exchanger, a water supply inlet by which supply water can be provided to the heat exchanger, and a water supply outlet by which heated water can be communicated from the heat exchanger. Additionally, the system includes a controller, a water supply outlet temperature sensor, a water supply flowmeter, and an actuator. The controller is configured to generate control signals based at least indirectly upon temperature measurements and flow measurements and to provide the control signals to the actuator to regulate a fluid flow of the heated heating fluid into the heat exchanger.

A water preconditioner system comprising a user interface for manually or automatically receiving inputs from a user, a mixing assembly including a plurality of control valves coupled to hot and cold water supply lines, and a controller in communication with the plurality of control valves and the user interface for controlling the operation of the system. The controller is configured to operate in a plurality of modes to precondition the water to one of a desired preset water dispensing temperature or a target temperature different from the desired preset water dispensing temperature.

A heating system of a managed fluid system can include a heat exchanger and a first temperature sensor device that measures an inlet temperature of a fluid flowing into the heat exchanger. The heating system can also include a second temperature sensor device that measures an outlet temperature of the fluid flowing out of the heat exchanger. The heating system can further include a controller communicably coupled to the first temperature sensor device and the second temperature sensor device. The controller can receive inlet temperature measurements made by the first temperature sensor device and outlet temperature measurements made by the second temperature sensor device. The controller can also evaluate the inlet temperature measurements and the outlet temperature measurements using at least one lookup table and at least one algorithm. The controller can subsequently determine an input rate of fuel used to heat the fluid flowing through the heat exchanger.

A hot water circulation system comprises a water heater having a cold-water inlet and a hot water outlet. A water pump circulates water through the water heater to produce hot water. The hot water is circulated to a thermal bypass valve, which is configured to close when hot water contacts a heat activated seal. A bypass circuit is coupled between the hot water outlet and the cold water inlet of the water heater. The bypass circuit prevents hot water from circulating from the hot water outlet to the cold-water inlet when the thermal bypass valve is open and promotes circulating hot water from the hot water outlet to the cold water inlet when the thermal bypass valve is closed. Upon a temperature sensor sensing hot water entering the cold-water inlet, the water heater turns of the water pump.

A heat pump may include a compressor configured to compress a refrigerant, a first temperature sensor provided in heating pipes connected to a heating device that heats an indoor space to sense a temperature of fluid flowing through the heating pipes, and a controller. The controller may be configured to determine whether a boiler is operating to heat an indoor space or is operating to supply hot water based on a sensing value of the first temperature sensor. The compressor may operate when the controller determines that the boiler is not operating to heat the indoor space and/or determines that the boiler is operating to supply hot water.

A hot-water supply device includes a hot-water dispenser supplying hot-water, a hot-water supply path supplying the hot-water to a hot-water supply tap, a circulation path carrying out instant hot-water operation which circulates and heats the hot-water remaining in the hot-water supply path, a first clock repeatedly measuring unit times in which a pattern of hot-water usage of a user makes a round, and a flow rate sensor detecting the supply of the hot-water from the hot-water supply tap. The control portion detects, for each of the unit times and based on detection signals of the flow rate sensor, a time zone in which hot-water supply operation is carried out, and reserves, based on a time zone in a first unit time in which the hot-water supply operation is carried out, a time zone in a second unit time following the first unit time for carrying out the instant hot-water operation.

A scale adhesion prevention operation of a circulation pump operated in an instant hot water operation is efficiently and appropriately performed. An instant hot water circulation path is formed to bypass a hot water tap outside a hot water supply device and to pass through a heat exchanger inside the hot water supply device by operating a circulation pump when the hot water tap is closed. A controller performs a protection operation which operates the circulation pump when a first condition in which stop of the circulation pump is continued for a first time is satisfied and a second condition related to stop of a hot water supply operation is further satisfied.

Provided is a hot-water supply device. A process performed by a control device of the hot-water supply device includes: a step of shifting an action mode of the hot-water supply device to an instant hot-water mode; a step of measuring an amount of water X; a step of determining that another tap interruption occurs when the amount of water X is equal to or greater than a basic flow amount Y+α; a step of stopping action of a circulation pump; a step of re-learning the amount of water X when the amount of water X is less than a basic flow amount Y−β; a step of ending the instant hot-water circulation mode when an end condition of the instant hot-water mode is satisfied; and a step of measuring the amount of water X when the end condition of the instant hot-water mode is not satisfied.