Overflow protection and monitoring devices capable of coupling to a drainage pan and may include: a drainage line; a base, the base including an input port; a dry section; and a wet section, the input port capable of coupling to the drainage pan; a base cover, the base cover removably coupled to the base, the base cover including a base cover output port capable of coupling to the drainage line; a fluid displacement mechanism located in the wet section, the fluid displacement mechanism including a fluid displacement mechanism output port; a fluid detection mechanism located in the wet section; and a base attachment, the base attachment coupled to the fluid displacement mechanism output port and the base cover output port, the base attachment including an air relief port and back-flow preventer; a control unit capable of energizing the fluid displacement mechanism upon receiving a signal from the fluid detection mechanism.

Flow heater comprising a housing having an inlet and an outlet, a plate shaped heating insert that is arranged in the housing and defines a flow path from the inlet to the outlet. According to this disclosure the plate shaped heating insert comprises a first heating plate, a second heating plate, and a plate support arranged between the first heating plate and the second heating plate, wherein the first heating plate and the second heating plate are arranged on opposite sides of the plate support, and the first heating plate and the second heating plate each comprise a substrate plate carrying a resistive layer.

A water heater has a water supply line, a heat exchanger in fluid communication with the water supply line, a heating element positioned proximate to the heat exchanger, such that when activated, the heating element conveys heat to the heat exchanger and thereby heating water supplied by the water supply line, an output line in fluid communication with the heat exchanger and configured to receive heated water therefrom, a flow sensor configured to cause the heating element to activate in response to sensing a predetermined water flow rate through the water heater, and a bypass flow line operably connected between the water supply line and the output line.

In an immediate hot water supply operation mode in which a circulation pump is activated while a hot water supply faucet is closed, a water heating apparatus forms an immediate hot water supply circulation path by an inner path and an outer path as being combined, the inner path including a heating mechanism including a combustion mechanism and a heat exchanger, the outer path bypassing the hot water supply faucet outside the water heating apparatus. The outer path includes a crossover valve. In the immediate hot water supply operation mode, a controller introduces intermittent combustion to control a detection temperature detected by the temperature sensor to a set temperature. In intermittent combustion, a minimum combustion state and a combustion stop state are alternately provided. In the minimum combustion state, a quantity of heat output from the combustion mechanism is reduced to a minimum value.

Apparatuses of an energy efficient water heater and methods for controlling the same are disclosed. In one embodiment, a water heater may include a water inlet configured to receive input water, an input water temperature sensor configured to detect a temperature of the input water, a user interface unit configured to receive an output water temperature setting selected by a user, a controller configured to determine a flow rate of an output water based on the input water temperature and the output water temperature setting, a heating unit configured to heat the input water to produce the output water, the controller is further configured to control the heating unit and a proportional flow restrictor to produce the flow rate of the output water, and a water outlet configured to transfer the output water at the flow rate of the output water.

A hot water supply system decouples an intelligent hot water storage system from a water heating engine system. The water heating engine system includes a plurality of instantaneous water heaters that provide for redundant operation for improved reliability. The intelligent hot water storage system includes a storage tank that encloses a volume for storage of water. The intelligent hot water storage system includes a recirculation loop driven by an integrated pump and operated by an integrated controller. By positioning the tank recirculation outlet and inlet farther apart from each other, additional usable volume of hot water is provided by the intelligent hot water storage system. Isolation valves positioned on the input and output of a recirculation pump in the recirculation loop facilitate repair or replacement of the recirculation pump. The hot water system provides for increased capacity while providing redundant heating engines in a smaller floor space than conventional systems.

The purpose of the present invention is to provide a heat exchanger capable of suppressing boiling and lime precipitation due to local overheating of a heating medium and at the same time improving heat transmittance efficiency. The heat exchanger of the present invention for achieving said purpose comprises: heating medium flow paths, through which a heating medium flows, inside a plurality of laminated plates; and a heat exchange unit in which combustion gas flow paths, through which a combustion gas flows, are alternately formed to be adjacent to each other, wherein the heat exchange units have a heating medium differential distribution unit which enables the flow rate of the heating medium to be differentially distributed to parallel heating medium flow paths of the heat exchange unit such that the flow rate of the heating medium passing through the parallel heating medium flow paths is balanced with the quantity of absorbed heat transmitted to the plates.

A water-heating system, including: a controller; a refrigerant-water heat exchanger for exchanging heat between refrigerant and water; a sensor circuit for measuring a current water temperature of water in a water heater and providing the current water temperature to the controller; a first refrigerant pipe for passing the refrigerant from a refrigerant source to the refrigerant-water heat exchanger; a second refrigerant pipe for passing the refrigerant from the refrigerant-water heat exchanger to the refrigerant source; a first water pipe for passing the water from the water heater to the refrigerant-water heat exchanger; a second water pipe for passing the water from the refrigerant-water heat exchanger to the water heater; and a water pump for pumping water from the water heater to the refrigerant-water heat exchanger via the first water pipe and from the refrigerant-water heat exchanger to the water heater via the second water pipe based on a control signal.

A water-heating system, including: a controller; a refrigerant-water heat exchanger for exchanging heat between refrigerant and water; a sensor circuit for measuring a current water temperature of water in a water heater and providing the current water temperature to the controller; a first refrigerant pipe for passing the refrigerant from a refrigerant source to the refrigerant-water heat exchanger; a second refrigerant pipe for passing the refrigerant from the refrigerant-water heat exchanger to the refrigerant source; a first water pipe for passing the water from the water heater to the refrigerant-water heat exchanger; a second water pipe for passing the water from the refrigerant-water heat exchanger to the water heater; and a water pump for pumping water from the water heater to the refrigerant-water heat exchanger via the first water pipe and from the refrigerant-water heat exchanger to the water heater via the second water pipe based on a control signal.

A water heater includes a heat exchanger. A controllable three-way proportional valve provides a proportionally controllable flow to the hot water inlet of the heat exchanger and a boiler return water outlet. A mixing tank mixes a cold water and a hot water. The mixing tank provides a time delayed mixed water. A temperature sensor is disposed in or on the mixing tank to measure a temperature of the time delayed mixed water to provide a time delayed mixed water temperature. A feedforward control process running on a processor adjusts a proportional operating position of the controllable three-way proportional valve to regulate a temperature of hot water at the hx domestic hot water outlet based on the temperature of the time delayed mixed water temperature. A method for controlling a hot water temperature of a water heater a water heater using a flowmeter based feedforward control are also described.