WO2013150536A2

WO2013150536A2 - A hot water system

Info

Publication number: WO2013150536A2
Application number: PCT/IL2013/050311
Authority: WO
Inventors: Yuval FRADKIN; Yoram RUBINSKY; Moshe ZAHARONI
Original assignee: Golan-Plastic Products Ltd.
Priority date: 2012-04-05
Filing date: 2013-04-04
Publication date: 2013-10-10
Also published as: WO2013150536A3

Abstract

A hot water system comprising a hot water source, a main hot water conduit drawing water from said hot water source, at least one secondary hot water conduit drawing water from said hot water source, a valve controlling the flow of water over time at least from said main hot water conduit, and a joint hot water conduit receiving water from the secondary hot water conduit and from the main hot water conduit downstream from the valve.

Description

A HOT WATER SYSTEM

RELATED APPLICATION/S

This application claims the benefit of priority under 35 USC § 119(e) of U.S, of Provisional Patent Application No. 61/620,447, filed April 5, 2012, the contents of which are incorporated herein by reference in their entirety.

FIELD AND BACKGROUND OF THE INVENTION

The present invention, in some embodiments thereof, relates to a system, apparatus and method for providing hot water and, more particularly, but not exclusively, to a system for providing an alternate route for the delivery of hot water.

Houghton, in US patent 4,924,536 discloses "A system of conserving water using non-electric ally operated, readily available plumbing equipment. The water to be saved with the system is water once heated which has cooled due to heat loss in a hot wafer [sic] line. This normally wasted cold water in the hot water line is often directed down the drain prior to dispensing of the hot water from a fixture. The system is adapted to divert the normally wasted cold water in the hot water line to a remotely positioned storage tank. The diverting process begins upon manual activation of a bypass valve positioned slightly upstream of the hot water valve of a typical hot water dispensing fixture. The cold water to be saved is diverted by the manual by-pass valve through by-pass piping leading into the storage tank. The storage tank is also plumbed with piping to the water input piping of each toilet tank reservoir of the building. The reservoir tanks of any of the toilets connected to the by-pass system are filled with the water which was previously stored in the storage tank."

Hadar, in US patent 6,674,963, discloses "Electrical heating apparatus includes an electrical heater in which the inlet conduit for inletting cold water to the electrical heater and/or the outlet conduit for outletting hot water thereto from the electrical heater is integrally formed with a pressure-responsive device which senses the flow rate to or through the electrical heater to control the energization of the electrical heater. The apparatus also includes a regulating valve constituted of a membrane and a stem having a head of convex configuration facing the membrane but normally spaced therefrom to define a flow-control passageway which creates differential pressures acting on the membrane tending to deform the membrane such as to maintain a relatively constant flow rate through the flow control passageway despite variations in water inlet pressure."

Krause, in US patent 8191513 B2, discloses "A system and a method for controlling a pump in a recirculating hot water system is provided. In one embodiment, the invention relates to a method for controlling a temperature of water in a recirculating hot water system including a storage tank for storing heated water, a recirculation conduit including a supply conduit for supplying the heated water to users via a plurality of outlets having a first outlet and a last outlet and a return conduit for returning an unused portion the heated water to the storage tank, a pump for circulating the heated water, the pump disposed along the return conduit, the method including measuring, at a point along the recirculation conduit, a temperature of the heated water provided from the storage tank, and controlling a speed of the pump, disposed along the return conduit, based on the measured temperature."

SUMMARY OF THE INVENTION

An aspect of some embodiments relates to a system, apparatus and method for providing hot water. In an exemplary embodiment, an alternate route for the delivery of hot water is provided.

According to an aspect of some embodiments of the present invention, there is provided a hot water system comprising a hot water source, a main hot water conduit drawing water from the hot water source, at least one secondary hot water conduit drawing water from the hot water source, a valve controlling the flow of water over time at least from the main hot water conduit, and a joint hot water conduit receiving water from the secondary hot water conduit and from the main hot water conduit downstream from the valve.

According to some embodiments, the valve is configured to cause water flowing from the main hot water conduit to gradually mix with water flowing from the at least one secondary hot water conduit in the joint hot water conduit when a certain threshold limits is reached. According to some embodiments, the conduit diameters are configured such that the amount of unused water is at least 25% less when using the valve to control the flow of water than the amount of unused water when not using the valve to control the flow of water.

According to some embodiments, the conduit diameters are configured such that the amount of unused water is at least 35% less when using the valve to control the flow of water than the amount of unused water when not using the valve to control the flow of water.

According to some embodiments, the conduit diameters are configured such that the amount of time it takes for the flow of hot water to begin is at least 10% less when using the valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using the valve to control the flow of water.

According to some embodiments, the conduit diameters are configured such that the amount of time it takes for the flow of hot water to begin is at least 20% less when using the valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using the valve to control the flow of water.

According to some embodiments, the valve is configured to initially block the flow of all or almost all water from the main hot water conduit.

According to some embodiments, the valve is configured to initially allow a reduced amount of water to flow from the main hot water conduit.

According to some embodiments, the valve is a thermostatic valve.

According to some embodiments, the system further comprises a temperature sensitive element, wherein the thermostatic valve is configured to gradually begin to increase the amount of water allowed to flow from the main hot water conduit when the water passing the temperature sensitive element reaches a certain temperature.

According to some embodiments, the valve is configured so that the water passing the temperature sensitive element is the water in the main hot water conduit.

According to some embodiments, the valve is configured so that the water passing the temperature sensitive element is the water in the joint hot water conduit.

According to some embodiments, the valve is configured so that the water passing the temperature sensitive element is the water in the secondary hot water conduit. According to some embodiments, the valve is pressure sensitive.

According to some embodiments, the valve is configured to gradually increase the amount of water allowed to flow from the main hot water conduit when the difference between the pressure of water in the secondary hot water conduit and the pressure of water in the joint hot water conduit reaches a certain level.

According to some embodiments, the valve is configured to gradually increase the amount of water allowed to flow from the main hot water conduit when the flow rate of the water in the joint hot water conduit reaches a certain level.

According to some embodiments, the at least one secondary conduit is located inside the main hot water conduit.

According to some embodiments, the at least one secondary conduit is located outside the main hot water conduit.

According to some embodiments, the at least one secondary hot water conduit has an internal diameter smaller than the internal diameter of the main hot water conduit.

According to an aspect of some embodiments of the present invention, there is provided a method for providing hot water comprising first delivering hot water from a hot water source via at least one secondary conduit to a point of use; gradually increasing the flow rate of hot water by mixing water from a main conduit with the hot water from the at least one secondary conduit; and controlling the flow of water over time from the main hot water conduit and from the at least one secondary hot water conduit.

According to some embodiments, a valve causes water flowing from the main hot water conduit to gradually mix with water flowing from the at least one secondary hot water conduit in a joint hot water conduit when a certain threshold level is reached.

According to some embodiments, the valve initially blocks the flow of all or almost all water from the main hot water conduit.

According to some embodiments, the valve initially allows a reduced amount of water to flow from the main hot water conduit.

According to some embodiments, the valve is a thermostatic valve.

According to some embodiments, the thermostatic valve gradually begins to increase the amount of water allowed to flow from the main hot water conduit when the water in at least one of the main hot water conduit, the joint hot water conduit and the secondary hot water conduit reaches a certain temperature.

According to some embodiments, the valve is pressure sensitive.

According to some embodiments, the valve gradually begins to increase the amount of water allowed to flow from the main hot water conduit when the difference between the pressure of water in the secondary hot water conduit and the pressure of water in the joint hot water conduit reaches a certain level.

According to some embodiments, the valve allows water to flow from the main hot water conduit when the flow rate of the water in the joint hot water conduit reaches a certain level.

According to an aspect of some embodiments of the present invention, there is provided an apparatus for providing hot water comprising a valve configured to control the flow of water from a main hot water conduit operating in conjunction with at least one secondary hot water conduit and a joint hot water conduit configured to receive water from the secondary hot water conduit and from the main hot water conduit downstream from the valve.

According to some embodiments, the valve is configured to cause water flowing from the main hot water conduit to gradually begin to mix with water flowing from the at least one secondary hot water conduit when a certain threshold is met.

According to some embodiments, the valve is configured to initially allow a reduced amount of water to flow from the main hot water conduit

According to some embodiments, the valve is a thermostatic valve.

According to some embodiments, the apparatus further comprises a temperature sensitive element, wherein the thermostatic valve is configured to gradually begin to increase the amount of water allowed to flow from the main hot water conduit when the water passing the temperature sensitive element reaches a certain temperature.

According to some embodiments, the valve is configured so that the water passing the temperature sensitive element is the water in at least one of the main hot water conduit, the joint hot water conduit and the secondary hot water conduit. According to some embodiments, the temperature sensitive element is a bi-metal spring which is configured to expand to allow water to flow more freely from the main hot water conduit.

According to some embodiments, wherein the temperature sensitive element is a wax element which is configured to expand to allow water to flow more freely from the main hot water conduit.

According to some embodiments, the valve is pressure sensitive.

According to some embodiments, the valve is configured to detect water pressure in at least one of the secondary hot water conduit and the joint hot water conduit.

According to some embodiments, wherein the valve is configured to allow hot water from a hot water source to bypass water sitting in a hot water conduit.

According to some embodiments, the valve is shaped to simultaneously fit at least one secondary hot water conduit and a main hot water conduit.

According to some embodiments, wherein the secondary hot water conduit is located inside the main hot water conduit.

According to some embodiments, the secondary hot water conduit is located outside and parallel to the main hot water conduit.

According to some embodiments, wherein the at least one secondary hot water conduit and a main hot water conduit are different sections of one sectioned conduit.

According to some embodiments, the at least one secondary hot water conduit has a diameter smaller than the diameter of the main hot water conduit.

According to an aspect of some embodiments of the present invention, there is provided an apparatus for providing hot water comprising a hot water channel; at least two separate hot water conduits located inside the hot water channel; a connector on the proximal end of the channel configured to connect the at least two separate hot water conduits fluidly to a hot water source; and a connector on the distal end of the channel configured to connect the at least two separate hot water conduits separately to different parts of one valve.

According to some embodiments, the at least two separate hot water conduits comprise a main hot water conduit; and a secondary hot water conduit located inside the main hot water conduit. According to some embodiments, the at least two separate hot water conduits comprise a main hot water conduit comprising a first section of the channel; and a secondary hot water conduit comprising a second section of the channel and located next to the main hot water conduit.

According to an aspect of some embodiments of the present invention, there is provided an apparatus for providing hot water comprising a valve comprising a first component configured to individually attach to a secondary hot water conduit located inside a main hot water conduit; and a second component configured to individually attach to the main hot water conduit; and configured to control the flow of water from at least one of the main hot water conduit and the secondary hot water conduit into a joint hot water conduit; wherein the control is based on at least one of the temperature of the water in the main hot water conduit; the temperature of the water in the joint hot water conduit; the temperature of the water in the secondary hot water conduit; the difference between the pressure of water in the secondary hot water conduit and the pressure of water in the joint hot water conduit; and the flow rate of the water in the joint hot water conduit.

According to an aspect of some embodiments of the present invention, there is provided an apparatus for providing hot water comprising a valve extension configured to attach to an existing valve and allow water to flow freely from a secondary hot water conduit, around the existing valve, into a joint hot water conduit which also receives water passing from a main hot water conduit through the valve.

Unless otherwise defined, all technical and/or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments, exemplary methods and/or materials are described below. In case of conflict, the patent specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and are not intended to be necessarily limiting. BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments are herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of embodiments. In this regard, the description taken with the drawings makes apparent to those skilled in the art how embodiments may be practiced.

In the drawings:

FIG. 1A is a schematic illustration of a hot water system comprising two separate hot water conduits and a valve, according to some embodiments;

FIG. IB is a schematic illustration of a hot water system comprising a sectioned hot water conduit or a conduit located inside a conduit and a valve, according to some embodiments;

FIGs. 2A and 2B are Flow Charts demonstrating the different steps of a hot water system utilizing a thermostatic valve, according to some embodiments;

FIGs. 2C and 2D are Flow Charts demonstrating the different steps of a hot water system utilizing a pressure sensitive valve, according to some embodiments;

FIGs. 3 A, 3B and 3C are conceptual diagrams of a hot water system comprising a secondary conduit inside a main conduit during different modes of use, according to some embodiments;

FIG. 3D is a Phase Chart demonstrating the different modes of a hot water system, according to some embodiments;

FIG. 4A is a graph comparing the volume of water over time using the valve to control the flow of water and not using the valve to control the flow of water, according to some embodiments;

FIG. 4B is a graph comparing the temperature of water over time while using the valve to control the flow of water and not using the valve to control the flow of water, according to some embodiments;

FIG. 5A is a schematic illustration of a hot water system comprising two separate hot water conduits, a valve and a hot water distributor, according to some embodiments;

FIG. 5B is a schematic illustration of a hot water system comprising a sectioned hot water conduit or a conduit located inside a conduit, a valve and a hot water distributor, according to some embodiments; FIG. 5C is a schematic illustration of the hot water system of FIG. 5A without a hot water distributor, according to some embodiments;

FIG. 5D is a schematic illustration of the hot water system of FIG. 5B without a hot water distributor, according to some embodiments;

FIG. 5E is a schematic illustration of the hot water system of FIG. 5D further comprising a cold water conduit, according to some embodiments;

FIG. 5F is a schematic illustration of the hot water system of FIG. 5B with the valve located downstream of the hot water distributor, according to some embodiments;

FIG. 6 is a schematic illustration of a hot water system comprising two separate hot water conduits, a valve, a hot water distributor and a cold water distributor, according to some embodiments;

FIG. 7 is a schematic illustration of a hot water system comprising two separate hot water conduits, a valve, a hot water distributor and a cold water distributor attached to the piping system of a bathroom, according to some embodiments;

FIG. 8 is a schematic illustration of a hot water system comprising two separate hot water conduits, a valve, a hot water distributor and a cold water distributor attached to the piping system of a multi-level home, according to some embodiments;

FIG. 9A is a cross-sectional view of the hot water conduits of FIG. 1A, not touching each other, according to some embodiments;

FIG. 9B is a cross-sectional view of the hot water conduits of FIG. 1A, touching each other, according to some embodiments;

FIG. 9C is a cross-sectional view of the hot water conduits of FIG. IB, containing one internal secondary conduit, according to some embodiments;

FIG. 9D is a cross-sectional view of the hot water conduits of FIG. IB, containing two internal secondary conduits of approximately equal diameter, according to some embodiments;

FIG. 9E is a cross-sectional view of the hot water conduits of FIG. IB, containing two internal secondary conduits of different diameters, according to some embodiments;

FIGs. 10A and 10B are cross-sectional views of the sectioned hot water conduit of FIG. IB, according to some embodiments; FIG. IOC is a cross-sectional view of the sectioned hot water conduit of FIG. IB divided into separate sections separated by rigid section separators, according to some embodiments;

FIG. 11A is a schematic illustration of a cross sectional view of a bi-metal thermostatic valve, shown in a closed position, according to some embodiments;

FIG. 11B is a schematic illustration of a cross sectional view of a bi-metal thermostatic valve, shown in an open position, according to some embodiments;

FIG. 12A is a schematic illustration of a cross sectional view of the bi-metal thermostatic valve shown in FIG. 11 attached to a conduit at each end of the valve, shown in a closed position, according to some embodiments;

FIG. 12B is a schematic illustration of a top diagonal view of the bi-metal thermostatic valve shown in FIG. 12A, according to some embodiments;

FIG. 13 A is a schematic illustration of a cross sectional view of a thermostatic valve with a bi-metal element and a valve extension, shown in a closed position, according to some embodiments;

FIG. 13B is a schematic illustration of a cross sectional view of a thermostatic valve with a bi-metal element and a valve extension, shown in an open position, according to some embodiments;

FIG. 14 is a schematic illustration of a 3-dimensional cross sectional view of a thermostatic valve with a wax element, shown in a closed position, according to some embodiments;

FIG. 15A is a schematic illustration of a cross sectional view of a pressure sensitive valve, shown in a closed position, according to some embodiments;

FIG. 15B is a schematic illustration of a cross sectional view of a pressure sensitive valve, shown in an open position, according to some embodiments; and

FIG. 16 is a schematic illustration of a prototype hot water system comprising a hot water conduit within a hot water conduit, a valve, a hot water distributor, a cold water distributor and a standard hot water conduit, according to some embodiments, which was used in an experiment. DESCRIPTION OF SPECIFIC EMBODIMENTS

The present invention, in some embodiments thereof, relates to a system, apparatus and method for providing hot water and, more particularly, but not exclusively, to providing an alternate path for the delivery of hot water.

An aspect of some embodiments relates to a system, apparatus and method for providing at least one secondary conduit as an alternative route to deliver hot water to a delivery point, with a valve controlling the flow of water over time from at least one of the secondary conduit and a main conduit, particularly from the main hot water conduit.

In an exemplary embodiment, the secondary hot water conduit has an internal diameter smaller than the internal diameter of a standard hot water conduit. According to some embodiments, the volume of water normally sitting in the narrower secondary conduit is less than the volume of sitting water in the standard hot water conduit. According to some embodiments, the smaller internal diameter potentially provides the advantage of reducing the amount of sitting water which runs down the drain while waiting for hot water to arrive. For example, the amount of sitting water which runs down the drain without use while waiting for the flow of hot water to begin may be at least 25% less when using the valve to control the flow of water than the amount of unused water when not using the valve to control the flow of water.

In an exemplary embodiment, the overall flow rate when using the valve to control the flow of water may eventually reach the same rate as the overall flow rate when using a standard sized conduit because, for example, the flow rate of the secondary hot water conduit combined with the flow rate of the main hot water conduit may be the same as the flow rate of a standard pipe.

According to some embodiments, the initial flow rate when the valve controls the flow of water will be lower than the flow rate of a standard sized conduit. Optionally, the flow rate when using the valve to control the flow of water will gradually increase as the valve opens and allows water from the main hot water conduit to join the water from the secondary hot water conduit, until the flow rate equals the flow rate of a standard hot water conduit.

A potential advantage of the invention is that it may work together with a standard sized conduit. For example, the main hot water conduit combined with the secondary hot water conduit may hold a sufficient volume of water to match the volume of the standard conduit. Alternatively, a secondary conduit may be retrofitted inside the standard conduit to act as a secondary conduit, with only a small decrease in volume due to the thickness of the wall of the secondary conduit.

According to some embodiments, the smaller internal diameter of the secondary conduit causes the water in the secondary conduit to flow at a greater velocity than the water sitting in a standard hot water conduit, even though the flow rate of the secondary hot water conduit is lower than the flow rate of the standard hot water conduit. Alternatively, the smaller internal diameter of the secondary conduit causes the water in the secondary conduit to flow at the same velocity or at a slower velocity than the water sitting in a standard hot water conduit.

According to some embodiments, the smaller internal diameter of the secondary conduit potentially provides the advantage of reducing the time necessary for hot water to arrive. For example, the amount of time it takes for the flow of hot water to begin may be at least 10% less when using the valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using the valve to control the flow of water. Alternatively, the amount of time it takes for the flow of hot water to begin may be approximately 10% more when using the valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using the valve to control the flow of water, even though less cold water drains off before the arrival of the hot water.

According to some embodiments, after a demand for hot or warm water is made, the valve initially allows only a reduced flow of water flowing from the main hot water delivery conduit to begin mixing with the water provided by the alternate hot water delivery conduit. Alternatively, the valve initially blocks all or almost all of the water flowing from the main hot water conduit

In an exemplary embodiment, the valve regulating the release of the water in the main hot water conduit is thermostatically regulated. Optionally, the thermostatic valve contains a bi-metallic element and/or a wax element which gradually expands in a certain temperature range, gradually converting the valve toward a fully open position and allowing the flow of water from the main hot water conduit to gradually increase.

In an exemplary embodiment, the temperature sensitive element is connected to a joint hot water conduit receiving water from both the main hot water conduit and the secondary hot water conduit. Optionally, the temperature sensitive element is configured to only allow water from the main hot water conduit to mix with water from the secondary hot water conduit at a rate at which the effect of the sitting, cold water in the main hot water conduit is sufficiently mitigated by the effect of the warmer water in the secondary conduit. Alternatively, the temperature sensitive element is connected to the main hot water conduit.

According to some embodiments, the valve regulating the release of the water in the main hot water conduit is pressure sensitive. Optionally, the pressure sensitive valve contains a pressure sensitive element which gradually expands as the difference between the pressure of water in the secondary hot water conduit and the pressure of water in the joint hot water conduit reaches a certain level. For example, as the pressure sensitive element gradually expands, the valve may be gradually converted to a fully open position, allowing the flow of water from the main hot water conduit to gradually increase. This configuration potentially provides the advantage of allowing the flow of water from the main hot water conduit to increase only when a need arises for additional water, for example, when more than one hot water tap is opened, according to some embodiments.

In an exemplary embodiment, the at least one secondary hot water conduit is located inside the main hot water conduit. Optionally or alternatively, the at least one secondary hot water conduit is located outside the main hot water conduit. Optionally or alternatively, the at least one secondary hot water conduit and the main hot water conduit are different sections of one conduit.

Before explaining at least one embodiment in detail, it is to be understood that the invention is not necessarily limited in its application to the details of construction and the arrangement of the components and/or methods set forth in the following description and/or illustrated in the drawings and/or the Examples. The invention is capable of other embodiments or of being practiced or carried out in various ways. System with Thermostatic Valve initially reducing flow of water from main hot water conduit

Referring now to the drawings, Figure 1A is a schematic illustration of a hot water system 100 comprising a main hot water conduit 104 and a secondary hot water conduit 106, according to some embodiments. In an exemplary embodiment, main hot water conduit 104 connects to a hot water source 102, such as a water boiler, at its proximal end and to a valve 108, at its distal end. Optionally, secondary hot water conduit 106 connects to hot water source 102, at its proximal end, and to joint hot water conduit 120 on its distal end. Alternatively, secondary hot water conduit 106 connects to a hot water source other than hot water source 102, at its proximal end.

According to some embodiments, water emerging from the main hot water conduit 104 through valve 108 continues through hot water conduit 114 and then joins secondary hot water conduit 106 at intersection 110. After passing intersection 110, the water may enter joint hot water conduit 120, leading to a water outlet 112, such as a shower nozzle, bath tub tap, sink tap or washing machine hot water inlet.

In an exemplary embodiment, when valve 108 is not in a completely open position, water does not flow freely from main hot water conduit 104 through valve 108 to hot water conduit 114, even when water outlet 112 is in an open position. Optionally, water initially flows from main hot water conduit 104 through valve 108 at a reduced level, as compared to a hot water conduit not using this system, as described below in the section entitled Phase I.

According to some embodiments, as valve 108 converts to a more open position, water begins to flow more freely, emerging from main hot water conduit 104, to join water from secondary hot water conduit 106 in joint conduit 120, while water outlet 112 is in an open position.

In an exemplary embodiment, secondary hot water conduit 106 has an internal diameter smaller than the internal diameter of a hot water standard conduit. This smaller internal diameter potentially provides the advantage of reducing the amount of sitting water which runs down the drain while waiting for hot water to arrive, according to some embodiments, as discussed below in the section entitled Conservation of Water. The smaller internal diameter also potentially provides the advantage of reducing the time necessary for hot water to arrive, according to some embodiments.

According to some embodiments, valve 108 is a thermostatic valve controlling the flow of water over time, particularly from the main hot water conduit, based on the temperature of the water in main hot water conduit 104 or in joint hot water conduit 120. Optionally, the thermostatic valve contains a temperature sensitive element configured to only allow water from the main hot water conduit to mix with water from the secondary hot water conduit at a rate at which the effect of the sitting, cold water in the main hot water conduit is sufficiently mitigated by the effect of the warmer water in the secondary conduit. Alternatively, the temperature sensitive element is located in a main hot water conduit, as discussed below in the section entitled Thermostatic Valve. For example, new hot water may arrive from hot water source 102 to replace the exhausted standing water in secondary hot water conduit 106, raising the temperature of the water in joint hot water conduit 120 sufficiently to keep the water reaching water outlet 112 at a comfortable temperature for showering even when a certain amount of water from main hot water conduit 104 is allowed to reach joint hot water conduit 120. Optionally, water outlet 112 is a thermostatic tap.

According to some embodiments, the at least one secondary hot water conduit is located outside the main hot water conduit. Optionally, the at least one secondary hot water conduit is parallel to the main hot water conduit, as described below in the section entitled Secondary Conduits.

According to some embodiments, main conduit 104 and/or secondary conduit 106 conduct at least one liquid other than water. Optionally or alternatively, main conduit 104 and/or secondary conduit 106 conduct at least one gas and/or a combination of at least one liquid and at least one gas. For example, cooling oils for machines may initially be conducted through a narrow secondary pipe in order to minimize the quantity of oils which are initially circulated, at a time when the machine being cooled is still not very hot. Afterwards, as the machine becomes warmer, the temperature of the cooling oil rises and the thermoregulated valve opens the main conduit, increasing the cooling oil volume and its capacity to cool. This method provides the potential advantage of adjusting the quantity of the circulated cooling oil according to the cooling needs of the machine to be cooled. Hot water conduit within a hot water conduit and sectioned conduit

Figure IB is a schematic illustration of a hot water system comprising a sectioned hot water conduit or a conduit located inside a conduit 124 and a valve 128, according to some embodiments. According to some embodiments, an internal secondary hot water conduit (not seen) is located inside a main hot water conduit which makes up the exterior portion of hot water conduit 124, as described below in the section entitled Secondary Conduits. Optionally, hot water conduit 124 is connected to hot water source 102 at its proximal end and to valve 128 on its distal end.

According to some embodiments, valve 128 controls the flow of water out of the external main hot water conduit. When valve 128 is in a closed position, water initially does not flow freely from the main hot water conduit to water outlet 132, even when water outlet 132 is in an open position.

According to some embodiments, when valve 128 is in an open position, water begins to flow, or begins to flow more freely, emerging from the main hot water conduit, joining water from the secondary hot water conduit in a joint hot water conduit 130 on the side of valve 128 opposite to hot water conduit 124, reaching water outlet 132 when water outlet 132 is in an open position.

According to some embodiments, conduit 124 is a sectioned hot water conduit and the at least one secondary hot water conduit and the main hot water conduit are different sections of one conduit, as described below in the section entitled Sectioned Conduit.

Steps and Phases

Figure 2A (steps 201-209) is a Flow Chart demonstrating the different steps of a hot water system, in which a Thermostatic Valve initially reduces the flow of water from the main hot water conduit, according to some embodiments.

Figures 3A, 3B and 3C are cross-sectional views of a hot water system comprising a secondary hot water conduit inside a main hot water conduit during different modes of use. Figure 3D is a Phase Chart demonstrating the different modes of a hot water system, according to some embodiments, according to some embodiments according to some embodiments. Phase I

Figures 2A is a Flow Chart demonstrating the use of the system illustrated in Figure IB with a Thermostatic Valve which initially reduces, but does not completely block, the flow of water from the main hot water conduit.

In step 201 in Figure 2A, a demand for hot water is made, for example, a water outlet such as a water tap is opened to a setting other than cold, such as warm or hot. Since the only valve blocking the flow of water from the secondary hot water conduit is the water outlet, the opening of the water outlet in step 201 leads to step 202 in which water flows freely from the hot water source, through the at least one secondary hot water conduit, past the valve controlling the flow of water from the main hot water conduit, into Joint Hot Water Conduit 130. Joint Hot Water Conduit 130 receives water from both the main hot water conduit (when its controlling valve 128 is open) and the secondary hot water conduit, and to the water outlet 132.

In both steps 201 and 202, the valve 128 controlling the flow of water from the main hot water conduit is not fully open, leading to a reduced flow of water from the main hot water conduit, while water flows freely from the secondary hot water conduit due to the opening of the water outlet 132, corresponding to Phase I of Figure 3D.

Phase I is illustrated in Figure 3A, in which an inner main hot water conduit with a valve 128 in a closed position 302 is situated inside an outer secondary hot water conduit with a valve in an open position 304, according to some embodiments. Optionally, the valve 128 controlling the main hot water conduit remains in a closed position in this phase because the temperature of the temperature sensitive element in valve 128 remains below a threshold. Phase II

In step 203, a threshold temperature is reached in the temperature sensitive element in the thermostatic valve, causing the valve to switch to the open position and leading to step 204 in which the thermostatic valve allows water to flow at a greater rate from the main hot water conduit to joint hot water conduit 130, and to the water outlet 132.

The system continues operating in this way until step 205 in which the previously stagnant water which was located in the main hot water conduit is exhausted and new water arrives from the hot water source in step 206, replacing the previously stagnant water in the main hot water conduit. Optionally the valve is thermostatic and the threshold level is a certain temperature. Optionally, the temperature sensitive element in the valve is sensitive to the temperature of water in the Joint Hot Water Conduit 130. Alternatively, the temperature sensitive element in the valve is sensitive to the temperature of water in the Main Hot Water Conduit.

In step 207, water from the hot water source continues flowing to both the main hot water conduit and the secondary hot water conduit. In steps 203 - 207, the valve 128 controlling the flow of water from both the main hot water conduit and from the secondary hot water conduit is open due to the temperature of the temperature sensitive element, corresponding to Phase II of Figure 3D. This phase is illustrated in Figure 3B, in which an inner main hot water conduit with a valve in an open position 306 is situated inside an outer secondary hot water conduit with a valve in an open position 304, according to some embodiments.

Phase III

In step 208, the water outlet is closed leading to step 209 in which water from the hot water source stops flowing to both the main hot water conduit and the secondary hot water conduit, although the valve 128 is still open to the flow of water from the main hot water conduit. The cessation of the arrival of new water from the hot water source results in a cooling of the water located in the main hot water conduit and the secondary hot water conduit.

In step 210, the temperature of the temperature sensitive element in the thermostatic valve lowers, leading to step 211 in which the temperature of the temperature sensitive element in the thermostatic valve falls below a threshold level. In this step, the thermostatic valve closes, blocking the flow of all or almost all of the water from the main hot water conduit.

The thermostatic valve only closes to water from the main hot water conduit in step 230. However, the valve controlling the flow of water from both the main hot water conduit and the secondary hot water conduit is closed from step 208 until step 210, effectively blocking the flow of additional water through valve 128 in steps 208 and 209 in addition to steps 210 and 211. This phase is illustrated in Figure 3C, in which an inner main hot water conduit with a valve in a closed position 302 is situated inside an outer secondary hot water conduit with a valve in a closed position 308, according to some embodiments. This phase corresponds to Phase III of Figure 3D.

In an exemplary embodiment, the temperature sensitive element in the thermostatic valve is a bi-metallic element. Alternatively, the temperature sensitive element in the thermostatic valve is a wax element.

Conservation of water

In an exemplary embodiment, secondary hot water conduit 106 has an internal diameter smaller than the internal diameter of a standard hot water conduit. This smaller internal diameter potentially provides the advantage of reducing the amount of sitting water which runs down the drain while waiting for hot water to arrive, since the volume of sitting water in the secondary conduit is less than the volume of sitting water in a standard hot water conduit. For example, secondary hot water conduit 104 may be a 16 mm conduit while a standard conduit not using this system may be a 25 mm conduit. According to some embodiments, the amount of sitting water which runs down the drain without use while waiting for the flow of hot water to begin may be at least 25% less when using the valve to control the flow of water than the amount of unused water when not using the valve to control the flow of water.

Figure 4A is a graph comparing the volume of water over time using the valve to control the flow of water and not using the valve to control the flow of water, according to some embodiments. The y-axis represents the volume (cm /sec) of water emerging from water tap and the x-axis represents the time (seconds).

In an exemplary embodiment, the mixture of unwanted water, which has been sitting in a main hot water conduit, with water arriving in a secondary hot water conduit directly from a hot water source, prevents the waste of some or all of the unwanted water. As indicated in the graph, the total volume of water emerging from the hot water conduit when using the valve to control the flow of water (line 402) starts out lower than the volume when using the valve to control the flow of water (line 406). Most of the volume while the valve to control the flow of water is initially provided by the secondary hot water conduit, as indicated by the gap between the total volume line (402) and the line corresponding to the main hot water conduit (404). The volume from the main hot water conduit (line 404) when using the valve to control the flow of water starts at zero, begins rising after several seconds and reaches parity with the volume when not using the valve to control the flow of water (line 406) after approximately 26 seconds.

Example

For example, a water tap leading to a shower nozzle may have been closed, trapping water which has already left the hot water source in the conduit between the hot water source and the shower nozzle. The water tap may remain closed for several hours, during which time the trapped water cools. When the tap is again opened, following this period of time in which the trapped water cooled, the trapped water is not allowed to reach the shower nozzle, while water arrives at the shower nozzle through a secondary conduit and additional water leaves the hot water source and mixes with the trapped water in the main hot water conduit. At a certain point, the mixture of new water from the hot water source with the trapped water is allowed to leave the main hot water and join the water in the secondary hot water conduit.

In an exemplary embodiment, more than 50% of the water which was sitting in a main hot water conduit is eventually used without being intentionally run off in order to evacuate the main hot water conduit and allow for the arrival of hot water. Optionally, the amount of water from the secondary hot water conduit which is allowed to run into the drain without use while waiting for the flow of hot water to reach a sufficient temperature is also more than 50% less than the amount of unused water which would have been allowed to run into the drain without use without using this system. In this embodiment, the total amount of water from the main hot water conduit and the secondary hot water conduit which is allowed to run into the drain without use while waiting for the flow of hot water to begin is at least 25% less when using the valve to control the flow of water than the amount of unused water when not using the valve to control the flow of water.

For example, Figure 4A depicts potential results using a 16 mm secondary pipe and a 25 mm main pipe, each with a length of 15 meters and a pressure of 4 bars, according to some embodiments. In a system utilizing a longer conduit, the overall volume of water is greater, generating a greater savings of water in terms of volume. As shown in Figure 4A, approximately 350-950 cm /sec, optionally 550 - 750 cm 3 /sec, optionally 650 cm 3 /sec may initially arrive at the water tap from the secondary hot water conduit when using the valve to control the flow of water, as compared with approximately 1600-2200 cm 3 /sec, optionally 1800-2000 cm 3 /sec, optionally 1,900 cm /sec without using the valve to control the flow of water.

After approximately 1-5 seconds, optionally 2-4 seconds, optionally 3 seconds, water from the main hot water conduit may gradually begin mixing with the water from the secondary hot water conduit, increasing the volume of water arriving at the water tap to approximately 1500-2100 cm 3 /sec, optionally 1700-1900 cm 3 /sec, optionally 1,800 cm /sec over the next 1-3 seconds, optionally 2 seconds.

The volume that is reached after approximately 3-7 seconds, optionally 4-6 seconds, optionally 5 seconds without using the valve to control the flow of water remains approximately 1,900 cm /sec. Assuming that the water reaches a temperature at which it is usable after approximately 4-8 seconds, optionally 5-7 seconds, optionally 6 seconds (408) when using the valve to control the flow of water and after approximately 3-7 seconds, optionally 4-6 seconds, optionally 5 seconds without using the valve to control the flow of water (410), a total of approximately 7,600 cm of water (1,900 cc/sec * 4 seconds) is wasted when not using the valve to control the flow of water versus a total of approximately 3,825 cm of water (3 seconds at 650 cc/sec plus an additional 3 seconds in which the flow rate rises from 650 cc/sec to 1800 cc/sec) is wasted when using the valve to control the flow of water.

According to this example, approximately 3,775 cm of water is saved when using the valve (7,600 cm 3 less 3,825 cm 3 ), approximately 50% of the 7,600 cm 3 of water wasted when not using the valve. Optionally, the amount of water allowed to run into the drain without use while waiting for the flow of hot water to begin is at least 10%, 20%, 60%, or 75% less when using the valve to control the flow of water than the amount of unused water when not using the valve to control the flow of water. Optionally, the amount of water allowed to run into the drain without use while waiting for the flow of hot water to begin during each use of a shower is approximately 1000- 8000 cm 3 , optionally 3000- 5000 cm 3^J, optionally 4000 cm 3 of water less when using the valve to control the flow of water than the amount of unused water when not using the valve to control the flow of water. Optionally, the water from the main hot water conduit eventually reaches the same flow level (412) or almost the same flow level when using the valve to control the flow of water as when not using the valve to control the flow level.

Alternatively, the length of both the 16 mm secondary pipe and the 25 mm main pipe, may be shortened to 2-8 meters, optionally 5 meters. Optionally, approximately 1,180 cm /sec may initially arrive at the water tap from the secondary hot water conduit when using the valve to control the flow of water, as compared with approximately 3,430 cm /sec without using the valve to control the flow of water. After approximately 2 seconds, water from the main hot water conduit may gradually begin mixing with the water from the secondary hot water conduit, increasing the volume of water arriving at the water tap to approximately 3,300 cm /sec over the next 1 second. The volume that is reached after approximately 3 seconds when not using the valve to control the flow of water is also 3,430 cm /sec. Assuming that the water reaches a temperature at which it is usable after approximately 5 seconds when using the valve to control the flow of water and after approximately 2 seconds without using the valve to control the flow of water, a total of approximately 10,290 cm (3,430 cc/sec * 3 seconds) is wasted without using the valve to control the flow of water versus a total of approximately 9,080 cm (2 sec at 1,180 cc/sec plus an additional 3 seconds in which the flow rate rises from 1,180 to 3,300 cc/sec) is wasted when using the valve to control the flow of water (approximately 12% less). Optionally, the amount of water allowed to run into the drain without use while waiting for the flow of hot water to begin is at least 10%, 30%, 50%, or 75% less when using the valve to control the flow of water than the amount of unused water when not using the valve to control the flow of water. Time

In an exemplary embodiment, the internal diameter of the secondary conduit is smaller than the internal diameter of a standard pipe. For example, the secondary conduit may be a 16 mm conduit while the standard required by local law may be a 25 mm for a hot water conduit providing hot water for an entire apartment. The smaller internal diameter potentially provides the advantage of reducing the time necessary for hot water to arrive. Optionally, the difference in water volume provided by the more narrow secondary hot water conduit, as compared with the standard hot water conduit, is compensated by the gradual addition of water from the main hot water pipe. Optionally, the combined volume of water eventually provided by the secondary hot water conduit and the main hot water conduit is at least as much as the volume of water provided by the standard hot water conduit.

Figure 4B is a graph comparing the temperature of water over time using the valve to control the flow of water and not using the valve to control the flow of water, according to some embodiments. The y-axis represents the Temperature (C°) of water emerging from water tap and the x-axis represents the time (seconds). Optionally, the system reduces the waste of time. In an exemplary embodiment, the amount of time it takes for the flow of hot water to begin is at least 20% less when using the valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using the valve to control the flow of water.

For example, as shown in Figure 4B, the water reaches a temperature at which it is usable after approximately 5-9 seconds, optionally 6-8 seconds, optionally 7 seconds (424) when using the valve to control the flow of water as compared with approximately 6-10 seconds, optionally 7-9 seconds, optionally 8 seconds without using the valve to control the flow of water (426), using approximately 13% less time. Optionally, the amount of time it takes for the flow of hot water to begin is at least 5%, 10%, 15%, 25%, 30%, 40% or 50% less when using the valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using the valve to control the flow of water.

In some embodiments, the amount of time it takes for the flow of hot water to begin is greater when using the valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using the valve to control the flow of water. This may be the case, for example, where the diameter of pipe leading to the valve is small.

According to some embodiments, the time difference whether less or more, is relatively small compared with the difference in water waste In an exemplary embodiment, difference between the water savings and time change increases as the pipe length increases. For example, the water savings may increase as the pipe length increases, while the time saving or loss remains unaffected by the pipe length. In those cases where the time required for suitable hot water to arrive is greater with the system, the benefit of the conserved water may outweigh the loss of time.

Mixture of water

Water from the main hot water conduit may be gradually mixed with the water provided by the alternate hot water conduit. For example, a valve may be placed in the main hot water conduit which allows water which has been sitting in the main hot water conduit to be released gradually to join the water in the secondary hot water conduit on its way to the water outlet. Optionally, the valve initially allows only a reduced flow of water flowing from the main hot water delivery conduit to begin mixing with the water provided by the alternate hot water delivery conduit immediately after a demand for hot or warm water is made. Alternatively, the valve initially blocks all or almost all of the water flowing from the main hot water conduit, as described below in the section entitled System with Thermostatic Valve initially blocking flow of water from main hot water conduit and in the section entitled System with Pressure Sensitive Valve initially blocking flow of water from main hot water conduit.

According to some embodiments, the bypassed water is gradually mixed with the water provided via the alternate route. For example, a valve may be placed in the main hot water conduit which allows water which has been sitting in the main hot water conduit to be released gradually to join the water in the secondary hot water conduit on its way to the water outlet, as shown by volume line 404 in the graph in Figure 4A. Optionally, the standing water is released until no standing water remains. Optionally, new hot water arrives from the hot water source to replace the exhausted standing water. Hot Water distributor

Figure 5A is a schematic illustration of a hot water system 500 comprising two separate hot water conduits, main hot water conduit 504 and secondary hot water conduit 506, receiving water from hot water source 502, a valve 508 and a hot water distributor 514, according to some embodiments. Optionally, hot water distributor 514 is attached to joint hot water conduit 520 receiving water from secondary hot water conduit 506 and main hot water conduit 504 on the distal side of intersection 510 and redirects the water which enters it to individual hot water conduits 516. The placement of valve 508 on the proximal, downstream side of hot water distributor 514 provides the potential advantage of allowing the system to act more efficiently when at least one water tap connecting to individual hot water conduits 516 is closed. For example, if only one water tap is open, the hot water provided by secondary hot water conduit 506 may be sufficient hot without the need to increase the flow of water from main hot water conduit 504. This efficiency is further explained below in the section entitled Pressure Sensitive Valve.

Figure 5B is a schematic illustration of a hot water system comprising a sectioned hot water conduit or a conduit located inside a conduit 524, a valve 528, hot water source 502 and a hot water distributor 514, according to some embodiments. Optionally, the conduit within a conduit is coaxial. Optionally, hot water distributor 514 is attached to joint hot water conduit 530 and redirects the water which enters it to individual hot water conduits 516.

Figure 5C is a schematic illustration of the hot water system of Figure 5A without a hot water distributor, according to some embodiments. Joint hot water conduit 520 leads directly to water tap 534. Figure 5D is a schematic illustration of the hot water system of Figure 5B without a hot water distributor, according to some embodiments. Joint hot water conduit 530 leads directly to water tap 534. Optionally, the system illustrated in Figures 5C and 5D is suitable for use in locations where hot water distributors are not used.

Figure 5E is a schematic illustration of the hot water system of Figure 5D further comprising a cold water conduit, according to some embodiments. Cold water conduit 536 leads directly to water tap 534.

Figure 5F is a schematic illustration of the hot water system of Figure 5B with valve 528 located downstream of hot water distributor 514, according to some embodiments. Water emerging from hot water source 502 enters hot water conduit 544, reaching hot water distributor 514. Hot water distributor 514 distributes water to individual hot water conduit 516 and individual hot water conduit 546. Individual hot water conduit 546 is a sectioned hot water conduit or a conduit located inside a conduit which connects to valve 528. Optionally, the conduit within a conduit is coaxial. Optionally, valve 528 leads to joint hot water conduit 530 which leads to water tap 534. Cold Water distributor

Figure 6 is a schematic illustration of a hot water system 600 comprising two separate hot water conduits, a main hot water conduit 604 and a secondary hot water conduit 606. Secondary hot water conduit 606 receives water from hot water source 602. The system further comprises a valve 608, a hot water distributor 614 and a cold water distributor 622, which receives water from main water conduit 640 and redirects the water which enters it to hot water source 602 and to individual cold water conduits 624, according to some embodiments. Optionally, hot water distributor 614 is attached to joint hot water conduit 620. Joint hot water conduit 620 receives water from secondary hot water conduit 606 and main hot water conduit 604 on the distal side of intersection 610 and redirects the water which enters it to individual hot water conduits 616.

Utilizing the system in a Bathroom

Figure 7 is a schematic illustration of a hot water system 700 comprising two separate hot water conduits, a main hot water conduit 704 and a secondary hot water conduit 706, receiving water from hot water source 702, a valve 708, a hot water distributor 714 and a cold water distributor 722. Main water conduit 740 connects to "T" junction 742. Some of the water reaching "T" junction 742 flows to hot water source 702 and some of the water reaching "T" junction 742 flows to cold water distributor 722.

Cold water distributor 722 distributes cold water to individual cold water conduits 724 and 728, according to some embodiments. Optionally, hot water distributor 714 is attached to joint hot water conduit 720 receiving water from secondary hot water conduit 706 and main hot water conduit 704 on the distal side of intersection 710 and redirects the water which enters it to individual hot water conduits 716 and 726.

According to some embodiments, the hot water system attaches to the piping system of a bathroom. Optionally, individual hot water conduit 726 provides hot water to a bathtub water tap 730, a shower nozzle 732 and a sink faucet 734. Optionally, the system is configured to work with a temperature controlled water tap. For example, bathtub water tap 730, shower nozzle 732 and/or sink faucet 734 is/are temperature controlled water taps. Optionally, individual cold water conduit 728 provides cold water to a bathtub water tap 730, a shower nozzle 732, a sink faucet 734 and a toilet reservoir 736. Utilizing the system in a House

Figure 8 is a schematic illustration of a hot water system 800 comprising two separate hot water conduits, a main hot water conduit 804 and a secondary hot water conduit 806. Secondary hot water conduit 806 receives water from hot water source 802. The system further comprises a valve 808, a hot water distributor 814 and a cold water distributor 822, which receives water from main water conduit 840 and redirects the water which enters it to hot water source 802 and to individual cold water conduits 824 and 828, according to some embodiments. Optionally, hot water distributor 814 is attached to joint hot water conduit 820 receiving water from secondary hot water conduit 806 and main hot water conduit 804 on the distal side of intersection 810. Optionally, hot water distributer 814 redirects the water which enters it to individual hot water conduits 812 and 816.

According to some embodiments, the hot water system attaches to the piping system of a multi-level home. Optionally, individual hot water conduit 812 provides hot water to a bathtub water tap 830, a shower nozzle 832 and sink faucets 834. Optionally, individual cold water conduit 826 provides cold water to a bathtub water tap 830, a shower nozzle 832, sink faucets 834 and a toilet reservoir 836.

Secondary Conduits

Figure 9A is a cross-sectional view of the hot water conduits of Figure 4A, according to some embodiments. Optionally, the at least one secondary hot water conduit is located outside the main hot water conduit. Optionally, main hot water conduit 904 and secondary hot water conduit 906 are parallel to each other. Optionally, secondary hot water conduit 906 has a smaller diameter than main hot water conduit 904.

According to some embodiments, main hot water conduit 904 and secondary hot water conduit 906 do not touch each other. Optionally, main hot water conduit 904 and secondary hot water conduit 906 are close to each other. Optionally, the close proximity of main hot water conduit 904 and secondary hot water conduit 906 allows the hot water of secondary hot water conduit 906 to heat the water in main hot water conduit 904.

Alternatively, main hot water conduit 904 and secondary hot water conduit 946 touch each other, as illustrated in Figure 9B, according to some embodiments. Optionally, the touching of main hot water conduit 904 and secondary hot water conduit 906 allows the hot water of secondary hot water conduit 906 to heat the water in main hot water conduit 904.

Figure 9C is a cross-sectional view of the sectioned hot water conduit or conduit located inside a conduit 124 hot water conduit of Figure IB, containing one internal secondary conduit, according to some embodiments. Optionally, hot water conduit 924 comprises outer portion 954, acting as a main hot water conduit, surrounding an inner conduit 956, acting as a secondary hot water conduit. A potential advantage of the system is that hot water flowing through inner conduit 956 heats the water in outer portion 954, according to some embodiments.

Figure 9D is a cross-sectional view of the sectioned hot water conduit or conduit located inside a conduit 124 hot water conduit of Figure IB, containing two internal secondary conduits of equal diameter, according to some embodiments. Optionally, hot water conduit 924 comprises outer portion 954, acting as a main hot water conduit, surrounding inner conduits 966 and 968, of equal diameter, acting as two secondary hot water conduits. Optionally, inner conduits 966 and 968 act as secondary hot water conduits carrying water of different temperatures. Alternatively, inner conduits 966 and 968 act as secondary hot water conduits carrying different liquids. Alternatively, inner conduit 966 acts as a secondary hot water conduit and inner conduit 968 acts as a cold water conduit.

Figure 9E is a cross-sectional view of the hot water conduit of Figure IB, containing two internal secondary conduits of different diameters, according to some embodiments. Optionally, hot water conduit 924 comprises outer portion 954, acting as a main hot water conduit, surrounding inner conduits 976 and 978, of different diameters, acting as secondary hot water conduits. Optionally, inner secondary hot water conduit 976 has a smaller diameter than inner secondary hot water conduit 978.

Heating water in the main hot water conduit

According to some embodiments, the initially bypassed water in the main hot water conduit is heated by new warm or hot water arriving from the hot water source and mixing with the bypassed water. Optionally, the bypassed water is heated by the hot water passing through a secondary conduit, for example, where the secondary conduit is inside the main hot water conduit. Optionally, the secondary conduit is outside the main hot water conduit but touches or is close enough to the main hot water conduit to heat the water in the main hot water conduit. Alternatively, the initially bypassed water in the main hot water conduit is heated by mixing with the water in the secondary hot water conduit at a sufficiently low flow rate to avoid causing a significant drop in the temperature of the water in the secondary hot water conduit.

Conduit Composition

According to some embodiments, the hot water conduit of Figure IB comprises an inner secondary hot water conduit is composed of a material which changes its diameter in accordance with the temperature of the water which flows through it. According to some embodiments, the conduits are composed of materials which expand as a result of exposure to heat, thereby changing the conduit's diameter to increase in accordance with temperature. Optionally, the conduits are composed of two different materials that each have a different thermal expansion factor, so that the secondary pipe diameter changes as the temperature changes. Optionally, when the temperature of the water which flows through the conduit is low, the diameter of the conduit is smaller and the flow of water in that conduit is low. Optionally, when the temperature of the conduit climbs, its water flow capacity climbs correspondingly. Optionally, the expansion and contraction of the secondary hot water conduit is sufficient to regulate the system without the need for a valve. Optionally or alternatively, the expanding and contracting secondary hot water conduit is used in conjunction with a valve.

Transporting hot and cold water in the same conduit

According to some embodiments, the hot water conduit of Figure IB comprises two interior conduits, one interior conduit acting as a secondary hot water conduit while a second interior conduit delivers cold water. Optionally, both interior conduits are internal to a main hot water conduit. For example, in Figure 9E, interior conduit 976 may be a secondary hot water conduit and interior conduit 978 may be a cold water conduit. Sectioned conduit

Figure 10A is a cross-sectional view of the sectioned hot water conduit of Figure IB, according to some embodiments. Optionally, the conduit is separated into at least two separate sections, one section acting as a main route for delivering hot water and the other section acting as a secondary route for delivering hot water. Optionally, sectioned conduit 1024 comprises three separate sections: section 1054, acting as a main route for delivering hot water, section 1056, acting as a secondary route for delivering hot water and section 1058, acting as a route for delivering cold water, separated by section separators 1050. Alternatively, section 1058 acts as an additional secondary hot water delivery section.

According to some embodiments, the sections are equal in size, as illustrated in Figure 10A. Alternatively, the sections are not equal in size, as illustrated in Figure 10B, in which section 1066, acting as the secondary hot water delivery section, and section 1068, acting as the cold water delivery section, are smaller than section 1054 which acts as the main hot water delivery section and are separated by section separators 1060. According to some embodiments, section 1054 acts as the main hot water delivery section and eventually carries a higher volume of water than section 1066.

According to some embodiments, section separators 1060 are rigid. For example, section separators 1060 may be composed of plastic. Alternatively, the section separators 1060 are not rigid, as illustrated in Figure IOC. Figure IOC is a cross- sectional view of the sectioned hot water conduit of Figure IB divided into separate sections separated by non-rigid section separators 1070, according to some embodiments. For example, section separators 1070 may be composed of air, air bubbles and/or other non-rigid materials.

Valve

According to some embodiments, the flow of water from the main hot water conduit is controlled by a valve which controls the mixture of water arriving at a water tap from the main hot water conduit and from a secondary hot water conduit over time. Optionally, the flow of water from the at least one secondary hot water conduit is not controlled by the valve. For example, the flow of water from the at least one secondary hot water conduit may be controlled only by the opening and closing of the water tap. According to some embodiments, the valve is connected only to the main hot water conduit. For example, main hot water conduit 104 in Figure 1A may be connected to valve 108 and one secondary hot water conduit 106 may not have any connection to valve 108. Alternatively, both the main hot water conduit and the secondary hot water conduit may be connected to the valve. For example, the main hot water conduit and the secondary hot water conduit contained in hot water conduit 124 in Figure IB may both be connected to valve 128. Optionally, only the water from the main hot water conduit is actually controlled by valve 128, while the water from the secondary hot water conduit freely passes through the valve. Alternatively, the flow of water from both the main hot water conduit and the water from the secondary hot water conduit are controlled by valve 128. Optionally, a secondary hot water conduit 106 located outside the main hot water conduit 104 may attach to a valve 108.

According to some embodiments, the valve is manually controlled. Optionally or alternatively, the valve is controlled by an element such as a temperature sensitive and/or pressure sensitive element.

According to some embodiments, the control of the flow of water out of the conduits by the valves allows hot water to flow rapidly from the hot water source to a water tap while bypassing standing cold water. Optionally, all or some of the standing water in the main hot water conduit is used.

Thermostatic Valve

In an exemplary embodiment, the valve regulating the release of the water in the main hot water conduit is thermostatically regulated. Optionally, the thermostatic valve contains a bi-metallic element and/or a wax element which gradually expand in a certain temperature range. For example, the valve may begin to open at approximately 25-45 degrees Celsius, optionally 30-40 degrees Celsius, optionally 35 degrees Celsius and may open completely at approximately 40-60 degrees Celsius, optionally 45-55 degrees Celsius, optionally 50 degrees Celsius.

According to some embodiments, the expansion of the bi-metallic element and/or wax element gradually converts the valve to a fully open position, allowing the flow of water from the main hot water conduit to gradually increase. Optionally, the temperature sensitive element is located in a joint hot water conduit, receiving water from both the main hot water conduit and the secondary hot water conduit, or in the main hot water conduit. This location of the temperature sensitive element potentially provides the advantage of allowing the mixture of water from the main hot water conduit only at a rate at which the effect of the coldness of the sitting water in the main hot water conduit is mitigated by the effect of the warmer water in the secondary conduit.

Thermostatic valve position

According to some embodiments, the temperature sensitive element of the thermostatic valve is located in a joint hot water conduit or a secondary hot water conduit in a location in which water from the main hot water conduit already joins the secondary hot water conduit.

Alternatively, the temperature sensitive element is located in the main hot water conduit. For example, the temperature sensitive element may be located at the end of the main hot water conduit which is near the water tap, at the end of the main hot water conduit near which is near the water heater or other hot water source, between the hot water source and the hot water distributor or at any other point along the conduit between the water tap and the hot water source. Each of these locations allow for thermostatic control of the water flow from the main hot water conduit, although the parameters of a particular water hot water system may work better when the thermostat is located in certain locations.

According to some embodiments, the water tap acts as a thermostatic valve. For example, both the main hot water conduit and the secondary hot water conduit may be attached a water tap containing an element which expands as the temperature of the water passing it increases, thereby allowing a greater flow of water from the main hot water conduit.

Thermostatic valve structure

According to some embodiments, the thermostatic valve is constructed to accommodate distribution to more than two conduits and/or to more than two sections of a conduit, for example, when the hot water system includes two secondary conduits or when the main conduit is divided into three sections, as described above in the section "Secondary Conduits."

Optionally, the thermostatic valve is built such that the side of the valve facing the source of hot water receives three conduits, while the second side, facing the tap, splits into two conduits, as is known in the art. In this way, end units do not require any adaptation in order to interface with this apparatus.

Thermostatic Valve Function

According to some embodiments, the valve opens the flow of water from the main hot water conduit when the water flowing from the main hot water conduit reaches a certain temperature. Optionally, the thermostat is mechanical. Optionally or alternatively, the thermostatic valve contains an element which expands at a certain temperature, thereby converting the valve to an open position allowing water to flow through and out of the valve.

Thermostatic valve with a bi-metallic element

In an exemplary embodiment, the valve regulating the release of the water in the main hot water conduit contains a temperature sensitive bi-metallic element. Figure 11A is a schematic illustration of a cross sectional view of a thermostatic valve (1100) containing a temperature sensitive bi-metallic element, shown in a closed position, according to some embodiments. Optionally, the thermostatic sensitive valve contains a thermostatic sensitive bi-metallic element which expands as its temperature increases. Optionally, the thermostatic sensitive bi-metallic element is a bi-metallic spring 1104 which expands sufficiently, when the temperature in the main hot water conduit reaches a certain level, to push a blocking elements 1102 sufficiently far in the direction of the flow direction 1110 against a standard spring 1180 to convert the valve to an open position, allowing water to flow from the main hot water conduit, through and out of the valve.

Figure 1 IB is a schematic illustration of a cross sectional view of a bi-metal thermostatic valve, shown in an open position, according to some embodiments. Blocking elements 1102 are sufficiently moved in the direction of the flow direction 1110 against standard spring 1180 to not touch wall 1160 which has a wider internal diameter at this point along the valve than at the point 1182 corresponding to the starting position of the blocking elements 1102.

Figure 12A is a schematic illustration of a cross sectional view of the thermostatic valve (1200) with a bi-metallic element, shown in Figure 11, attached to a conduit at each end of the valve, shown in a closed position, according to some embodiments. Optionally, bi-metallic spring 1204 expands sufficiently at a certain temperature to push blocking element 1202 and allow water to flow out of the outer, main hot water conduit. Optionally, the valve is connected to an incoming sectioned hot water conduit or a conduit located inside a conduit 1292. Optionally, hot water conduit 1292 is a double 25 mm PEXGOL conduit. Optionally, the incoming sectioned hot water conduit or conduit located inside a conduit has an 11 mm internal diameter. Optionally, hot water conduit 1292 is coaxial.

Figure 12B is a schematic illustration of a top diagonal view of the bi-metal thermostatic valve 1290 shown in Figure 12A, according to some embodiments. The conduits on either end are connected by the valve and standard connectors 1394 and are fastened by standard fitting 1396 for ¾" x 25 mm PEXGOL conduit.

In an exemplary embodiment, the diameter of the main hot water conduit and/or the joint hot water conduit is the size required by local law, while the diameter of the secondary hot water conduit is smaller than the size required by law. The smaller diameter of the secondary hot water conduit provides the potential advantage of allowing the secondary hot water conduit to more efficiently provide hot water when the demand for hot water is less than full, for example where only one tap is open.

Valve extension

Figure 13A is a schematic illustration of a cross sectional view of an apparatus

1300 comprising a thermostatic valve 1314 with a valve extension 1312 and a temperature sensitive bi-metallic spring 1304, shown in a closed position, according to some embodiments. In an exemplary embodiment, valve extension 1312 is attached to standard thermostatic valve 1314, allowing hot water from secondary hot water conduit 1316 to bypass standard valve 1314 and flow freely in flow direction 1310 into joint hot water conduit 1318. Optionally, at room temperature, bi-metallic spring 1304 does not push sufficiently on blocking element 1302 to allow water to flow freely from main hot water conduit 1316, through thermostatic valve 1314, into joint hot water conduit 1318, while water flows freely from secondary hot water conduit 1320.

In an exemplary embodiment, bi-metallic spring 1304 expands sufficiently, when the temperature in joint hot water conduit 1318 and/or main hot water conduit 1316 reaches a certain level to begin converting thermostatic valve 1314 to an open position, allowing water to begin flowing more freely from main hot water conduit 1316, through thermostatic valve 1314, into joint hot water conduit 1318. Figure 13B is a schematic illustration of a cross sectional view of the thermostatic valve 1314 of Figure 13A shown in an open position, according to some embodiments.

Thermostatic valve with a wax element

In an exemplary embodiment, the valve regulating the release of the water in the main hot water conduit contains a temperature sensitive wax element. Figure 14 is a schematic illustration of a 3-dimensional cross sectional view a thermostatic valve 1400 with a temperature sensitive wax element, shown in a closed position, according to some embodiments. Optionally, temperature sensitive wax element 1496 must expand sufficiently to push blocking element 1402 against spring 1404 sufficiently to allow the water to begin to flow or to flow at an increased rate out of the outer, main hot water conduit through the inner connector 1494 between the valve and the main hot water conduit. Optionally, water is always allowed to flow out of the inner, secondary hot water conduit through holes 1490 leading to the outer connector 1492 between the valve and the secondary hot water conduit.

Retrofitting

In an exemplary embodiment, the system may be installed in existing hot water systems, as well as in new ones. For example, a secondary hot water conduit may be added to an existing hot water system. Optionally, the proximal end of the added secondary hot water conduit connects to the same hot water source to which the existing main hot water conduit connects. Optionally, a valve is added to the distal end of the added secondary hot water conduit. Optionally, a conduit is added to the valve connecting the water emerging from the valve with the existing main hot water conduit. Optionally, the valve is a standard temperature sensitive or pressure sensitive valve with a valve extension attached to it to allow the free flow of water from the added secondary hot water conduit.

Self-powering

In an exemplary embodiment, connection to a power source is not required. Optionally, the lack of a need for a power source makes installation of the system simple and inexpensive. Alternatively, some elements of the system may be powered by an independent power source. Optionally, the power source is an electric line. Optionally or alternatively, the power source is a battery. For example, a thermometer controlling the valve and/or an actuator connected to the thermometer may be powered by an independent power source. System with Thermostatic Valve initially blocking flow of water from main hot water conduit

Figure 2B is a Flow Chart demonstrating the use of the system illustrated in Figure IB with a Thermostatic Valve which initially blocks the flow of all or almost all of the water from the main hot water conduit, according to some embodiments.

Phase I

In step 221 in Figure 2B, a demand for hot water is made, leading to step 222 in which water flows freely from the hot water source, through the at least one secondary hot water conduit, past the valve into Joint Hot Water Conduit 130, and to the water outlet 132. In steps 221 and 222, the valve 128 controlling the flow of water from the main hot water conduit is closed, blocking the flow of all or almost all of the water from the main hot water conduit, while water flows freely from the secondary hot water conduit due to the opening of the water outlet 132. This phase corresponds to Phase I of Figure 3D, which is illustrated in Figure 3 A, according to some embodiments. Phase II

In step 223, a threshold temperature is reached in the temperature sensitive element in the thermostatic valve, causing the valve to switch to the open position. This switch leads to step 224 in which the Thermostatic Valve allows water to begin flowing or to flow at a greater rate from the Main Hot Water Conduit to Joint Hot Water Conduit 130 and to the water outlet 132. The system continues operating in this way until step 225 in which the previously stagnant water which was located in the main hot water conduit is exhausted and new water arrives from the hot water source in step 226, replacing the previously stagnant water in the main hot water conduit. In step 227, water from the hot water source continues flowing to both the main hot water conduit and the secondary hot water conduit. In steps 223 - 227, the valve 128 controlling the flow of water from both the main hot water conduit and from the secondary hot water conduit is open due to the temperature of the temperature sensitive element, corresponding to Phase II of Figure 3D. This phase is illustrated in Figure 3B, according to some embodiments.

Phase III

In step 228, the water outlet is closed leading to step 229 in which water from the hot water source stops flowing to both the main hot water conduit and the secondary hot water conduit, although the valve 128 is still open to the flow of water from the main hot water conduit. In step 230, the temperature of the temperature sensitive element in the thermostatic valve lowers, leading to step 231 in which the temperature of the temperature sensitive element in the thermostatic valve falls below a threshold level. In this step, the thermostatic valve closes, blocking the flow of all or almost all of the water from the main hot water conduit.

The thermostatic valve only closes to water from the main hot water conduit in step 230. However, the valve controlling the flow of water from both the main hot water conduit and the secondary hot water conduit is closed from step 228 until step 230, effectively blocking the flow of additional water through valve 128 in steps 228 and 229 in addition to steps 230 and 231. This phase is illustrated in Figure 3C, which corresponds to Phase III of Figure 3D. In an exemplary embodiment, the temperature sensitive element in the thermostatic valve is a bi-metallic element. Alternatively, the temperature sensitive element in the thermostatic valve is a wax element. System with Pressure Sensitive Valve initially reducing the flow of water from main hot water conduit

Pressure Sensitive Valve

According to some embodiments, the valve regulating the release of the water in the main hot water conduit is pressure sensitive. Optionally, the pressure sensitive valve contains a pressure sensitive element which gradually expands as the difference between the pressure of water in the secondary hot water conduit and the pressure of water in the joint hot water conduit reaches a certain level. This expansion gradually converts the valve to a fully open position and allows the flow of water from the main hot water conduit to gradually increase. This conversion of the valve toward a fully open position potentially providing the advantage of allowing the flow of water from the main hot water conduit to increase only when a need arises for additional water, for example, when more than one hot water tap is opened.

Figure 15A is a schematic illustration of a cross-sectional view of a pressure sensitive valve 1500, shown in a closed position, according to some embodiments. Optionally, the pressure sensitive valve contains a pressure sensitive element 1504. Pressure sensitive element 1504 moves sufficiently, when the difference between the flow rate in the secondary hot water conduit and the flow rate in the joint hot water conduit reaches a certain level, to push blocking elements 1502 sufficiently far in the direction of the flow direction 1510 to convert the valve to an open position. The opening of the valve allows water to flow from the main hot water conduit, through and out of the valve. Optionally, the secondary hot water conduit may be a 16 mm conduit and the main hot water conduit may be a 25 mm conduit. Optionally, the secondary hot water conduit and the main hot water conduit may be the same size.

According to some embodiments, the movement of the pressure sensitive element depends on the difference between the flow rate in the main hot water conduit and the flow rate in the joint hot water conduit. Optionally or alternatively, the movement of the pressure sensitive element depends on the difference between the flow rate in the main hot water conduit and the flow rate in the secondary hot water conduit. Optionally or alternatively, the movement of the pressure sensitive element depends on the flow rate in the main hot water conduit alone. Optionally or alternatively, the movement of the pressure sensitive element depends on the flow rate in the secondary hot water conduit alone. Optionally or alternatively, the movement of the pressure sensitive element depends on the flow rate in the joint hot water conduit alone. Optionally, a decrease in the flow rate in the secondary hot water conduit or in the joint hot water conduit results from the opening of more than one water tap to a warm or hot setting.

Figure 15B is a schematic illustration of a cross sectional view of a pressure sensitive valve, shown in an open position, according to some embodiments. Optionally or alternatively, the valve opens the flow of water from the main hot water conduit when the difference between the pressure of water in the interior secondary hot water conduit and the pressure of water in the main hot water conduit exceeds a certain value.

Hot water distributor with pressure sensitive valve

The advantage of the placement of valve 508 (in Figure 5) on the proximal, downstream side of hot water distributor 514 is described above in the section entitled Hot Water Distributor. The use of the hot water distributor together with a pressure sensitive valve also provides the potential advantage of allowing the system to act more efficiently when at least one water tap connecting to individual hot water conduits 516 is closed. For example, if only one water tap is open, the hot water provided by secondary hot water conduit 506 may flow at a sufficient rate without the need to increase the flow of water from main hot water conduit 504. For example, only one water tap may be open at one time and only water from secondary hot water conduit 506 may be used. If, in the middle of that use, a second water tap is opened, for example where a person is using the shower and, in the middle of the shower, a washing machine is in use and makes a demand for hot water, the system may detect an increase in the difference in pressure of the water in the joint hot water conduit and of the water in the secondary hot water conduit. Following that detection, the system may increase the flow of water from the main hot water conduit in order to maintain a proper level of pressure in the water reaching the shower nozzle.

Figures 2C is a Flow Chart demonstrating the use of the system illustrated in Figure IB, with a pressure sensitive valve which initially reduces the flow of water from the main hot water conduit, according to some embodiments.

Phase I

In step 241 in Figure 2C, a demand for hot water is made, leading to step 242 in which water flows freely from the hot water source, through the at least one secondary hot water conduit, past the valve controlling the flow of water from the main hot water conduit 128, into Joint Hot Water Conduit 130, and to the water outlet 132. In steps 241 and 242, the valve 128 controlling the flow of water from the main hot water conduit is not fully open, leading to a reduced flow of water from the main hot water conduit, while water flows freely from the secondary hot water conduit due to the opening of the water outlet 132, corresponding to Phase I of Figure 3D. Phase I is illustrated in Figure 3A, according to some embodiments.

Optionally, the valve 128 controlling the main hot water conduit remains in a closed position in this phase because the difference between the pressure of water in the Secondary Hot Water Conduit and the pressure of water in the Joint Hot Water Conduit 130 does not reach a level sufficient to cause a change in a pressure sensitive element in the valve.

Phase II

In step 243, the difference between the pressure of water in the secondary hot water pipe and the pressure of water in the joint hot water pipe reaches a threshold level, causing the valve to begin switching to the open position. As the valve switches to the open position it leads to step 244 in which the pressure sensitive valve allows water to flow at a greater rate from the Main Hot Water Conduit to Joint Hot Water Conduit 130 and to the water outlet 132. The system continues operating in this way until step 245 in which the previously stagnant water which was located in the main hot water conduit is exhausted and new water arrives from the hot water source in step 246, replacing the previously stagnant water in the main hot water conduit. In step 247, water from the hot water source continues flowing to both the main hot water conduit and the secondary hot water conduit. In steps 243 - 247, the valve 128 controlling the flow of water from both the main hot water conduit and from the secondary hot water conduit is open due to the flow level or levels sensed by the pressure sensitive element, corresponding to Phase II of Figure 3D. This phase is illustrated in Figure 3B, according to some embodiments.

Phase III

In step 248, the water outlet is closed leading to step 249 in which water from the hot water source stops flowing to both the main hot water conduit and the secondary hot water conduit, although the valve 128 is still open to the flow of water from the main hot water conduit. In step 250, the difference between the pressure of water in the secondary hot water pipe and the pressure of water in the joint hot water pipe reduces below a threshold, leading to step 251 in which the pressure sensitive valve closes, reducing the flow of the water from the main hot water conduit.

The pressure sensitive valve only closes to water from the main hot water conduit in step 250. However, the valve controlling the flow of water from both the main hot water conduit and the secondary hot water conduit is closed from step 248 until step 250, effectively blocking the flow of additional water through valve 128 in steps 228 and 249 in addition to steps 250 and 251, as illustrated in Figure 3C. This phase corresponds to Phase III of Figure 3D.

System with Pressure Sensitive Valve initially blocking flow of water from main hot water conduit Figure 2D is a Flow Chart demonstrating the use of the system illustrated in

Figure IB with a pressure sensitive valve which initially blocks the flow of all or almost all of the water from the main hot water conduit, according to some embodiments.

Phase I

Figure 2B is a Flow Chart demonstrating the use of the system illustrated in

Figure IB with a pressure sensitive valve which initially blocks the flow of all or almost all of the water from the main hot water conduit, according to some embodiments. In step 261 in Figure 2B, a demand for hot water is made, leading to step 262 in which water flows freely from the hot water source, through the at least one secondary hot water conduit, past the valve controlling the flow of water from the main hot water conduit 128, into Joint Hot Water Conduit 130, and to the water outlet 132. In steps 261 and 262, the valve 128 controlling the flow of water from the main hot water conduit is closed, blocking the flow of all or almost all of the water from the main hot water conduit, while water flows freely from the secondary hot water conduit due to the opening of the water outlet 132, corresponding to Phase I of Figure 3D. Phase I is illustrated in Figure 3 A, according to some embodiments.

Phase II

In step 263, the difference between the pressure of water in the secondary hot water pipe and the pressure of water in the joint hot water pipe reaches a threshold level, causing the valve to begin switching to the open position. This switch to the open position leads to step 264 in which the pressure sensitive valve allows water to begin flowing or to flow at a greater rate from the main hot water conduit to joint hot water conduit 130 and to the water outlet 132.

The system continues operating in this way until step 265 in which the previously stagnant water which was located in the main hot water conduit is exhausted and new water arrives from the hot water source in step 266, replacing the previously stagnant water in the main hot water conduit. In step 267, water from the hot water source continues flowing to both the main hot water conduit and the secondary hot water conduit.

In steps 263 - 267, the valve 128 controlling the flow of water from both the main hot water conduit and from the secondary hot water conduit is open due to the flow level or levels sensed by the pressure sensitive element, corresponding to Phase II of Figure 3D. This phase is illustrated in Figure 3B, according to some embodiments.

Phase III

In step 268, the water outlet is closed leading to step 269 in which water from the hot water source stops flowing to both the main hot water conduit and the secondary hot water conduit, although the valve 128 is still open to the flow of water from the main hot water conduit. In step 270, the difference between the pressure of water in the secondary hot water pipe and the pressure of water in the joint hot water pipe reduces below a threshold, leading to step 271 in which the pressure sensitive valve closes, blocking the flow of all or almost all of the water from the main hot water conduit.

The pressure sensitive valve only closes to water from the main hot water conduit in step 230. However, the valve controlling the flow of water from both the main hot water conduit and the secondary hot water conduit is closed from step 268 until step 270, effectively blocking the flow of additional water through valve 128 in steps 268 and 269 in addition to steps 270 and 271, as illustrated in Figure 3C. This phase corresponds to Phase III of Figure 3D.

It is expected that during the life of a patent maturing from this application many relevant technologies will be developed and the scope of the term hot water system is intended to include all such new technologies a priori.

As used herein the terms "about" and approximately refer to ± 10%.

The terms "comprises", "comprising", "includes", "including", "having" and their conjugates mean "including but not limited to".

The term "consisting of means "including and limited to".

The term "consisting essentially of" means that the composition, method or structure may include additional ingredients, steps and/or parts, but only if the additional ingredients, steps and/or parts do not materially alter the basic and novel characteristics of the claimed composition, method or structure.

As used herein, the singular form "a", "an" and "the" include plural references unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" may include a plurality of compounds, including mixtures thereof.

Throughout this application, various embodiments of this invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

Whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range. The phrases "ranging/ranges between" a first indicate number and a second indicate number and "ranging/ranges from" a first indicate number "to" a second indicate number are used herein interchangeably and are meant to include the first and second indicated numbers and all the fractional and integral numerals therebetween.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination or as suitable in any other described embodiment. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

Various embodiments and aspects of the present invention as delineated hereinabove and as claimed in the claims section below find experimental support in the following examples. EXPERIMENTAL EXAMPLE

Reference is now made to the following example, which together with the above descriptions illustrate some embodiments in a non-limiting fashion.

Figure 16 is a schematic illustration of a prototype hot water system 1600 comprising a hot water conduit located inside a conduit hot water conduit, a valve, a hot water distributor, a cold water distributor and a standard hot water conduit, according to some embodiments, which was used in an experiment. Parallel hot water conduits 1624 and 1650 connect hot water source 1602 to water taps 1612 and 1642 in basin 1644, respectively. Water conduit 1640 is a main water conduit delivering water to the hot water source and also to cold water distributor 1622. Water conduits 1644 are individual cold water conduits emanating from cold water distributor 1622 and delivering water to water taps 1612 and 1642.

Parallel hot water conduits 1624 and 1650 are 3 - meter Golan standard pex conduits. The conservation of water may be greater when conduits longer than 3 meters are used.

Hot water conduit 1624 is a conduit located inside a conduit, consisting of 16 mm secondary hot water conduit (not seen) located inside 25 mm pex pipe main hot water conduit which comprises the outer portion of hot water conduit 1624. Hot water conduit 1650 is a standard pexgol 20 mm pipe. Hot water conduit 1624 uses the system while hot water conduit 1650 does not use the system. Thermostatic valve 1608, controlling the flow of water from the main hot water conduit, is attached to the end of a tip attached to hot water conduit 1624, such that the 8 mm internal secondary hot water conduit is "Normally Open," while the outer main hot water conduit is "Normally Closed."

After being closed for several hours, water taps 1612 and 1642 were simultaneously opened to a hot setting and the time it took for the water emanating from each tap to reach 40 degrees Celsius was measured, as was the amount of water that was allowed to run off into the drain until that point was reached.

It took 7 seconds for the water emanating from water tap 1612 (connected to hot water conduit 1624 and using the valve to control the flow of water) to reach 40 degrees Celsius. During these 7 seconds, the amount of water that was allowed to run off into the drain was approximately 1800 ml.

It took 8 seconds for the water emanating from water tap 1642 (connected to hot water conduit 1650 and not using the valve to control the flow of water) to reach 40 degrees Celsius. During these 8 seconds, the amount of water that was allowed to run off into the drain was approximately 2600 ml.

Approximately 16% less time was wasted waiting for the arrival of sufficiently hot water (7 seconds compared with 8 seconds) and approximately 31% less water was allowed to run off into the drain until sufficiently hot water arrived. (1800 ml compared with 2600 ml).

Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. To the extent that section headings are used, they should not be construed as necessarily limiting.

Claims

WHAT IS CLAIMED IS:

1. A hot water system comprising:

a hot water source;

a main hot water conduit drawing water from said hot water source;

at least one secondary hot water conduit drawing water from said hot water source;

a valve controlling the flow of water over time at least from said main hot water conduit; and

a joint hot water conduit receiving water from said secondary hot water conduit and from said main hot water conduit downstream from said valve.

2. A system according to Claim 1, wherein said valve is configured to cause water flowing from said main hot water conduit to gradually mix with water flowing from said at least one secondary hot water conduit in said joint hot water conduit when a certain threshold limits is reached.

3. A system according to claim 1 or claim 2, wherein the conduit diameters are configured such that the amount of unused water is at least 25% less when using said valve to control the flow of water than the amount of unused water when not using said valve to control the flow of water.

4. A system according to any of claims 1 - 3, wherein said conduit diameters are configured such that the amount of unused water is at least 35% less when using said valve to control the flow of water than the amount of unused water when not using said valve to control the flow of water.

5. A system according to any of claims 1 - 4, wherein said conduit diameters are configured such that the amount of time it takes for the flow of hot water to begin is at least 10% less when using said valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using said valve to control the flow of water.

6. A system according to any of claims 1 - 5, wherein said conduit diameters are configured such that the amount of time it takes for the flow of hot water to begin is at least 20% less when using said valve to control the flow of water than the amount of time it takes for the flow of hot water to begin when not using said valve to control the flow of water.

7. A system according to any of claims 1-6, wherein said valve is configured to initially block the flow of all or almost all water from said main hot water conduit.

8. A system according to any of claims 1-7, wherein said valve is configured to initially allow a reduced amount of water to flow from said main hot water conduit.

9. A system according to any of claims 1-8, wherein said valve is a thermostatic valve.

10. A system according to claim 9, further comprising a temperature sensitive element, wherein said thermostatic valve is configured to gradually begin to increase the amount of water allowed to flow from said main hot water conduit when the water passing said temperature sensitive element reaches a certain temperature.

11. A system according to claim 10, wherein said valve is configured so that said water passing said temperature sensitive element is the water in said main hot water conduit.

12. A system according to claim 10, wherein said valve is configured so that said water passing said temperature sensitive element is the water in said joint hot water conduit.

13. A system according to claim 10, wherein said valve is configured so that said water passing said temperature sensitive element is the water in said secondary hot water conduit.

14. A system according to any of claims 1-8, wherein said valve is pressure sensitive.

15. A system according to claim 14, wherein said valve is configured to gradually increase the amount of water allowed to flow from said main hot water conduit when the difference between the pressure of water in said secondary hot water conduit and the pressure of water in said joint hot water conduit reaches a certain level.

16. A system according to claim 14, wherein said valve is configured to gradually increase the amount of water allowed to flow from said main hot water conduit when the flow rate of the water in said joint hot water conduit reaches a certain level.

17. A system according to any of claims 1-16, wherein said at least one secondary conduit is located inside said main hot water conduit.

18. A system according to any of claims 1-16, wherein said at least one secondary conduit is located outside said main hot water conduit.

19. A system according to any of claims 1-18, wherein said at least one secondary hot water conduit has an internal diameter smaller than the internal diameter of said main hot water conduit.

20. A method for providing hot water comprising

first delivering hot water from a hot water source via at least one secondary conduit to a point of use;

gradually increasing the flow rate of hot water by mixing water from a main conduit with said hot water from said at least one secondary conduit; and

controlling the flow of water over time from said main hot water conduit and from said at least one secondary hot water conduit.

21. A method according to Claim 20, wherein a valve causes water flowing from said main hot water conduit to gradually mix with water flowing from said at least one secondary hot water conduit in a joint hot water conduit when a certain threshold level is reached.

22. A method according to claim 21, wherein said valve initially blocks the flow of all or almost all water from said main hot water conduit.

23. A method according to claim 21 or claim 22, wherein said valve initially allows a reduced amount of water to flow from said main hot water conduit.

24. A method according to any of claims 21-23, wherein said valve is a thermostatic valve.

25. A method according to claim 24, wherein said thermostatic valve gradually begins to increase the amount of water allowed to flow from said main hot water conduit when the water in at least one of said main hot water conduit, said joint hot water conduit and said secondary hot water conduit reaches a certain temperature.

26. A method according to any of claims 20-23, wherein said valve is pressure sensitive.

27. A method according to Claim 26, wherein said valve gradually begins to increase the amount of water allowed to flow from said main hot water conduit when the difference between the pressure of water in said secondary hot water conduit and the pressure of water in said joint hot water conduit reaches a certain level.

28. A method according to Claim 26, wherein said valve allows water to flow from said main hot water conduit when the flow rate of the water in said joint hot water conduit reaches a certain level.

29. An apparatus for providing hot water comprising a valve configured to control the flow of water from a main hot water conduit operating in conjunction with at least one secondary hot water conduit and a joint hot water conduit configured to receive water from said secondary hot water conduit and from said main hot water conduit downstream from said valve.

30. An apparatus according to Claim 29, wherein said valve is configured to cause water flowing from said main hot water conduit to gradually begin to mix with water flowing from said at least one secondary hot water conduit when a certain threshold is met.

31. An apparatus according to Claim 29 or Claim 30, wherein said valve is configured to initially block the flow of all or almost all water from said main hot water conduit.

32. An apparatus according to any of claims 29-31, wherein said valve is configured to initially allow a reduced amount of water to flow from said main hot water conduit.

33. An apparatus according to any of claims 29-32, wherein said valve is a thermostatic valve.

34. An apparatus according to claim 33, further comprising a temperature sensitive element, wherein said thermostatic valve is configured to gradually begin to increase the amount of water allowed to flow from said main hot water conduit when the water passing said temperature sensitive element reaches a certain temperature.

35. An apparatus according to claim 34, wherein said valve is configured so that said water passing said temperature sensitive element is the water in at least one of said main hot water conduit, said joint hot water conduit and said secondary hot water conduit.

36. An apparatus according to any of claims 34-35, wherein said temperature sensitive element is a bi-metal spring which is configured to expand to allow water to flow more freely from said main hot water conduit.

37. An apparatus according to any of claims 34-35, wherein said temperature sensitive element is a wax element which is configured to expand to allow water to flow more freely from said main hot water conduit.

38. An apparatus according to any of claims 29-32, wherein said valve is pressure sensitive.

39. An apparatus according to Claim 38, wherein said valve is configured to detect water pressure in at least one of said secondary hot water conduit and said joint hot water conduit.

40. An apparatus according to any of Claims 29-39, wherein said valve is configured to allow hot water from a hot water source to bypass water sitting in a hot water conduit.

41. An apparatus according to any of Claims 29-40, wherein said valve is shaped to simultaneously fit at least one secondary hot water conduit and a main hot water conduit.

42. An apparatus according to any of Claims 29-41, wherein said secondary hot water conduit is located inside said main hot water conduit.

43. An apparatus according to any of Claims 29-41, wherein said secondary hot water conduit is located outside and parallel to said main hot water conduit.

44. An apparatus according to any of Claims 29-41, wherein said at least one secondary hot water conduit and a main hot water conduit are different sections of one sectioned conduit.

45. An apparatus according to any of Claims 29-44, wherein said at least one secondary hot water conduit has a diameter smaller than the diameter of said main hot water conduit.

46. An apparatus for providing hot water comprising

a hot water channel;

at least two separate hot water conduits located inside said hot water channel a connector on the proximal end of said channel configured to connect said at least two separate hot water conduits fluidly to a hot water source; and

a connector on the distal end of said channel configured to connect said at least two separate hot water conduits separately to different parts of one valve.

47. An apparatus according to claim 46, wherein said at least two separate hot water conduits comprise:

a main hot water conduit; and

a secondary hot water conduit located inside said main hot water conduit.

48. An apparatus according to claim 46, wherein said at least two separate hot water conduits comprise:

a main hot water conduit comprising a first section of said channel; and a secondary hot water conduit comprising a second section of said channel and located next to said main hot water conduit.

49. An apparatus for providing hot water comprising:

a valve comprising:

a first component configured to individually attach to a secondary hot water conduit located inside a main hot water conduit; and

a second component configured to individually attach to said main hot water conduit; and configured:

to control the flow of water from at least one of said main hot water conduit and said secondary hot water conduit into a joint hot water conduit; wherein

said control is based on at least one of:

the temperature of the water in said main hot water conduit; the temperature of the water in said joint hot water conduit; the temperature of the water in said secondary hot water conduit; the difference between the pressure of water in said secondary hot water conduit and the pressure of water in said joint hot water conduit; and

the flow rate of the water in the joint hot water conduit.

50. An apparatus for providing hot water comprising a valve extension configured to attach to an existing valve and allow water to flow freely from a secondary hot water conduit, around said existing valve, into a joint hot water conduit which also receives water passing from a main hot water conduit through said valve.