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.

Efficient shower tray with a static heat recovery device integrated in its surface, accessible and easy to clean that channels used water, causing it to run over the outer surface of a flat heat exchanger integrated in the surface of the tray, while cold water which is pre-heated before being mixed circulates inside the heat exchanger, reducing the quantity of hot water required and hence the energy required for heating water. The outer surface over which used grey water runs is accessible and easy to clean, thus ensuring simple and continuous maintenance, and the flat design of the heat exchanger allows the heat exchanger to be mounted flush with a surface, with a reduced height, and to be used without restrictions by persons having reduced mobility.

The assembly can accommodate a grey water lifting pump in order to conduct the water for re-use or discharge.

Provided is a hot water distribution system comprising a water heater, a water pump, a controller, a temperature sensor, a point-of-use, and a diverting valve capable of directing water from the water heater to either the point-of-use or back to the water heater.

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.

The heat exchanger tray provided herein may include a base, a cover, and a heat exchange coil. The base may include a cutout and a bottom portion with one or more sidewalls forming a serpentine path for wastewater. The cover may be positioned within the cutout of the base to create a space between the base and the cover. The cover may include one or more protruding portions that engage with the one or more sidewalls of the bottom portion of the base to enclose the serpentine path. The heat exchange coil may be positioned in and along at least a portion of the serpentine path between the base and the cover. Fresh water may flow through the heat exchange coil. Wastewater may flow through the serpentine path between the base and the cover, such that the wastewater may heat the fresh water flowing through the heat exchange coil.

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 has first and second passes arranged in counter-flow orientation. The heat recovery apparatus is made from commonly available materials. It has a hot side for grey water, and a cold side for fresh water under pressure. The heat recovery apparatus extracts heat from grey water to pre-heat water for a water heater. The fresh water is carried in passes in series, each pass being immersed in a grey water sump in a plastic pipe. The water level in the sump is high enough to immerse the dominant portion of the fresh water pass in grey water. Both ends of the fresh water coil are carried out through the same upper end pipe closure, without a penetration in the pipe wall. The entire assembly may be enclosed in a unitary external housing with easily accessible connection fittings.

New forms of self-sterilizing and antiseptic surfaces are provided. In some embodiments, a handled surface or GUI comprises internal hardware performing a heavy rinse of the handled surface triggered by an end-of-use function. In other embodiments, pressure on a handled surface instead causes the surface to uniformly exude water and other antiseptic compositions from a refillable source.

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.

The invention relates to a drainage channel for sanitary facilities, in particular shower facilities, with a channel body extending in a longitudinal direction, comprising: at least one first channel section having a bottom and at least two side walls arranged opposite one another at the bottom, wherein the first channel section is adapted to accommodate at least one heat exchanger unit for heat recovery; and at least one second channel section with a receiving area for receiving a channel cover element, which adjoins the first channel section above, wherein
the channel body has at least one undercut through which the receiving area of the second channel section is arranged transversely to the longitudinal direction within at least one of the side walls, in particular both side walls, of the first channel section.