The present invention describes a water recirculation system intended for recycling of water or discarding of water not suitable to recycle, said water recirculation system (1) comprising a flow path for recirculation (50), at least one water treating unit (6), and a sensor unit (7) arranged for measurement of at least water quality, and wherein the sensor unit (7) is connected to a control unit which decides if water should be recycled or discarded in a point of separation (30) based on the measurement of the water quality, said water recirculation system (1) also comprises a first heating source (00), and wherein the water recirculation system (1) also comprises a second heating source (200).

The concepts relate to reducing energy loss associated with hot water systems. One example can monitor hot water use in a system. Upon completion of the hot water use, the example can recover some of the hot water from hot water lines into a water heater that heated the hot water. The method can also deliver the recovered hot water to the water heater in a manner that affects operation of a heating element of the water heater.

A hot water unit fluid supply control system comprises a switching device coupled to a hot water unit, a rainwater tank and a potable water source. The switching device is configured to selectively switch between a first state, which allows fluid communication between the hot water unit and the rainwater tank, and a second state, which allows fluid communication between the hot water unit and the potable water source. The hot water unit fluid supply control system comprises a control unit configured to: receive fluid characteristic information associated with fluid in the hot water unit from one or more sensors; activate or deactivate a pump of the rainwater tank based on a comparison of a fluid characteristic parameter of the fluid characteristic information with requirements of the hot water unit to thereby cause the switching device to assume the first or second state.

An air conditioning system, comprising an outdoor unit and an indoor heat exchange mechanism. The indoor heat exchange mechanism comprises an air conditioner indoor unit and a first heat exchange mechanism used for at least one among water cooling, water heating and space heating. The present air conditioning system integrates various functions into one, such as air-conditioning refrigeration, air-conditioning heating, producing household cold water, producing household hot water, and home heating by means of connecting indoor units for cooling and heating, a water cooling mechanism, a water heating mechanism and a device for floor heating located indoors to one outdoor unit. Moreover, the system directly utilizes high-temperature refrigerant to heat water for floor heating.

An apparatus and method for recovering heat from a liquid medium, including a heat exchanger having heat exchanger cells, which are thermally separate from each other, for receiving the liquid medium, each of the cells has a sensor for determining temperature of the liquid medium located therein; a pipeline for conducting drinking water and/or heating water, which pipeline extends through at least one of the cells; a supply line wherein the liquid medium is conducted; controllable flaps through which the liquid medium can be selectively fed from the supply line to the cells; a sensor for measuring temperature of the liquid medium in the supply line, the flaps are controlled in an open-loop and/or closed-loop manner such that the liquid medium is supplied from the supply line to the heat exchanger cell that has a current temperature which is the least colder than the gray water in the supply line.

The instant invention provides for a kit and method of raising inlet temperature of a water supply by utilizing thermodynamic properties associated with difference in temperatures across a gradient and friction. In particular a portion of an inlet supply pipe is disposed in a sewer line such that the opposing flow of waste water and related material interacts with the inlet piping by increasing the temperature thereof.

A grey water heat recovery apparatus is disclosed in which heat is transferred between a grey water stream and a fresh water stream. The apparatus comprises: a grey water flow path leading from a source inlet to a drain outlet; a plurality of heat exchangers arranged in said grey water flow path; a separator arranged upstream of said heat exchangers, arranged to separate grey water from the source inlet into a plurality of parallel sub-paths, each sub-path being lead to one of the heat exchangers; and a collector arranged downstream of said heat exchangers, arranged to reassemble the grey water from the sub-paths into a single flow path. Each heat exchanger comprises a grey water tube extending from the separator to the collector, and an outer tube surrounding at least a part of the grey water tube, the outer tube defining an annular space around the grey water tube. A fresh water flow path formed within the annular spaces around the grey water tubes in the heat exchangers has a flow direction being opposite to the flow direction of the grey water.

A preheating heat exchanger allows heat exchange between cooling water on an outlet side of an auxiliary cooling heat exchanger and supply water that has passed through a preheating bypass path.

A heat exchanger (1) is specified having a housing (2), in which a primary side (3) having a primary-side flow path (5) is arranged between an upstream connector 6) and a downstream connector (7) and a secondary side (4) having a secondary-side flow path (10) is arranged between an inflow connector (11) and an outflow connector (12), wherein the primary side (3) and the secondary side (4) are in heat-transferring connection along a heat exchanger section (15) and a first temperature sensor (16) is arranged in the region of the outflow connector (12). The desire is to improve the ability to regulate and monitor the heat exchanger (1). To this end, there is provision for at least one second temperature sensor (18-20, 24, 25) to be arranged on the heat exchanger section (15) and for both temperature sensors (16; 18-20, 24, 25) to be connected to an evaluation device (21).

A heat exchanger for heating fresh water using heat from wastewater in a shower or bathtub. The heat exchanger has a drain pan, a heat exchanger unit that is arranged in the drain pan, and a distributing element for distributing draining wastewater over the heat exchanger unit. The heat exchanger unit has multiple tube portions that follow one another sequentially and are connected to one another by diverting portions. Each two horizontally running tube portions that follow one another and that are thus connected by a deflecting portion are arranged one over the other, and wastewater, which is dripping or flowing down, is sprinkled on or flows over the tube portions one after the other.