AU2004240166B2 - System and Method to Reduce Water Wastage - Google Patents

Description

56 1 System and method to reduce water wastage Field of the invention The present invention relates to methods and systems for the recovery and or re-use of 5 expelled water from hot water heating systems. Background of the invention Water in many locations is a precious commodity. Water heaters in many instances have pressure and temperature relief valves, which are designed to operate on when ever over temperature or over pressure conditions are present to prevent damage to the hot water system. 0 Such over temperature and pressure systems result in the wastage of water from the system. In countries like Australia, where water can sometimes be scarce, and governments impose water restrictions on a regular basis, the saving of water can be deemed to be a high priority. Summary of the invention 15 The present invention provides a water heater expelled water re-use system having a storage tank to heat water therein, with at least one mains pressure cold water inlet to said storage tank to deliver water to be heated in said storage tank, a hot water outlet from said storage tank to deliver heated water, and an over-temperature and or over-pressure relief valve operatively associated with said storage tank to allow the egress of water from said storage tank 20 when an over temperature or over pressure condition is present in said storage tank, said relief valve having an outlet through which relieved water passing out of said valve can pass to a liquid collection tank having a vent which vents to atmosphere, said collection tank having connection to a venturi through which mains pressure water flow will flow to draw said relieved water from said collection tank. 25 The relieved water drawn into said mains pressure water flow proceeds to a cold water outlet on the premises. The relieved water drawn into said mains pressure water flow proceeds to the cold water inlet to said storage tank. The mains pressure water flow which enters said venturi is provided from the hot water 30 outlet of said storage tank, and proceeds to a hot water outlet on the premises.

56 2 Between said collection tank and said venturi there is included a valve means. This valve can be controlled so that once a predetermined amount of relieved water is located in said collection tank said valve will open, allowing said relieved water to pass into said venturi. A one way valve can also be located between said collection tank and said venturi. 5 The vent can include restriction means to prevent or limit the ingress of contaminants such as bacteria, viruses, germs etc. The restriction means can include one or more of the following: a filter; flow trap. The system can include the feature that the vent includes a vent valve means whereby when said relief valve opens, the vent valve also opens and vents the collection tank to o atmosphere. The vent valve opens when said relief valve opens and closes when said relief valve closes, by means of one or more of the following: mechanical coupling; electrical and or solenoid coupling; hydraulic coupling. The system can also include a bypass around the venturi, so that when high flow rates are required of from the mains pressure water flow passing through the venturi, the by pass will 15 allow the higher flow rates. The present invention also provides a method of re-using expelled water from a water heating system, said method comprising the steps of: a) receiving relieved water from an over-temperature and or over-pressure relief valve into liquid collection tank; 20 b) passing a mains pressure water flow through a venturi, allowing said venturi to draw said relieved water from said collection tank. The can also include the step of passing the mains pressure water flow and combined relieved water to a cold water outlet. The cold water outlet can be the cold water inlet to said water heating system. 2 5 The method can also include the step of providing the mains pressure water flow from the hot water outlet from said water heating system and passing the combined mains pressure water flow and combined relieved water to a hot water outlet. The method can further include the step of providing said collection tank with a vent to atmosphere. The vent can include a restriction means to preventing ingress of contaminants, such 0 as dust, bacteria, viruses, etc. The present invention provides a water heating system having a water heater expelled water re-use system as described above, or which utilises the method described above.

56 3 Brief Description of the Drawing Embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings in which: figure 1 which schematically represents an embodiment of the invention; 5 figure 2 schematically represents a second embodiment of the invention; figure 3 schematically represents a third embodiment of the invention; and figure 4 schematically represents a fourth embodiment of the invention. Detailed description of the embodiments and examples Illustrated in figure 1, is a water heating system, generally designated by the roman D numeral XX. The system includes a storage tank 1, which receives cold water to be heated via a cold water inlet 2. Not illustrated is one or more electric heating elements, or a gas burner and flue system which is used to heat the water contained in the storage tank 1. Hot water stored in the storage tank 1 will exit via a hot water outlet 9 at the top of the tank. The storage tank 1 is pressurised under mains pressure. .5 As the water in the storage tank 1 heats up, there are times when the temperature or the pressure goes over a predetermined magnitude. 1N the event of this, the storage tank 1 is provided with an over temperature and or over pressure relief valve 3. As soon as an over temperature or over pressure condition has been attained inside the storage tank 1, the valve 3 will open causing water from in the storage tank 1 to exit thereby decreasing the pressure inside zo the storage tank 1. In prior art systems, this water simply proceeds to waste, and more often than not, is simply allowed to fall on the ground near to the storage tank 1. The system XX has a liquid collection tank 5 located near to the storage tank 1, which will receive the flow of relieved water (being that water which exits the storage tank 1 via the valve 3). The collection tank 5 has a vent 4, which vents to atmosphere. It is preferable that the ?5 vent 4 includes some safety devices such as contaminant restrictions like filters, and such like to prevent the ingress of contaminants such as dust, bacteria, virus etc. The collection tank 5 has an outlet 10, which is located in its base. The outlet 10 can be a conduit which has its inlet integrally formed in the base of the collection tank 5, or its can be simply a hose which has its inlet near to the base of the collection tank 5. 0o Associated with the outlet 10 is a valve 6 which will close the passage out of the collection tank 5 if insufficient water is present in the collection tank 5. The valve 6 can be 56 4 controlled by any appropriate means, such as a float system or a float valve, an solenoid valve and associated liquid detection system. Downstream from the valve 6 is a venturi 8 which receives a flow of mains pressure water 7 therethrough. The flow 7 causes a reduced pressure in the venturi 8 which will draw 5 water out of the collection tank 5 if the valve 6 is open due to sufficient relieved water being present in the collection tank 5. The relieved water combines with the mains pressure water and goes off for use in the water system of the premises at which the system XX is located. Illustrated in figure 1 is an optional bypass system, made up of a conduit 12 and a valve 11, whereby the venturi 8 can be bypassed, if ever the flow required from the mains pressure 0 flow 7 is higher than the venturi 8 will allow. The valve 11 can be made to open to allow the bypass action in response to a predetermined pressure differential, when the tap which receives the the mains pressure flow 7 is opened. If the tap is opened partially, then only the flow through the venturi 8 will be provided. However, as the tap is opened further, a greater pressure differential is generated. This pressure differential can be calibrated to a spring biased valve 15 member on the valve 11, whereby once the pressure differential exceeds a certain value, the valve member can overcome the spring force biasing the valve 11 closed. Other means of additionally controlling the valve 11 can be provided, for example, when the valve 6 remains closed the bypass valve 11 can be in the open condition. This could be achieved by a solenoid valve or mechanical linkage. 20 Illustrated in figure 2 is a second system XXI which also embodies the system XX of figure 1, showing a first means by which to provide mains pressure to the venturi 8. In figure 2 the main pressure water flow 7 provided to the venturi 8 is provided by a cold water mains. The outlet from the venturi 8 can be directed to any cold water outlet such a cold water tap in a bathroom, kitchen or possibly to a garden tap, in which case the venturi 8 will only operate when 25 a garden tap is opened. Illustrated in figure 3 is a third system XXII which also embodies the system XX of figure 1. The system XXII has the main pressure water flow 7 provided to the venturi 8 from a cold water mains supply, however, the output of the venturi 8 is fed to the cold water inlet 2 of the storage tank 1. By this means the relieved water is fed back to be heated. 30 Illustrated in figure 4 is fourth system XXIII which also embodies the system XX of figure 1. The system XXIII differs from the systems XXI and XXII in that the mains pressure supply to the venturi 8 is provided by the main pressure hot water outlet 9, with the outlet from 56 5 the venturi 8 proceeding to a hot water outlet such as may exist in a kitchen or bathroom or for hot water supply to a dishwasher. An improvement on the systems described above includes that the valve 3 is coupled to a valve (not illustrated) on the vent 4, so that the vent 4 remains closed until such time as the 5 valve 3 is caused to operate by means of the presence of an over temperature or over pressure condition being present in the storage tank 1. The valve 3 can be couple to the vent valve by any appropriate means including mechanical coupling, or by electrical and or solenoid operation. By locating the venturi 8 onto a tap terminated branch of a premises' water reticulation system, eg on a piped branch which terminates at a toilet cistern, garden tap, gray water system o (being a system that utilises recycled water) tap or a dishwasher tap, the systems described above will have little or no issues with any possible contamination of the relieved water being re-used. It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text. All of these different combinations constitute various alternative aspects of the invention. 15 The foregoing describes embodiments of the present invention and modifications, obvious to those skilled in the art can be made thereto, without departing from the scope of the present invention.

Claims (21)

1. A water heater expelled water re-use system having a storage tank to heat water therein, with at least one mains pressure cold water inlet to said storage tank to deliver water to be heated in said storage tank, a hot water outlet from said storage tank to deliver heated water, and an over-temperature and or over-pressure relief valve operatively associated with said storage tank to allow the egress of water from said storage tank when an over temperature or over pressure condition is present in said storage tank, said relief valve having an outlet through which relieved water passing out of said valve can pass to a liquid collection tank having a vent which vents to atmosphere, said collection tank having connection to a venturi through which mains pressure water flow will flow to draw water from said collection tank.

2. A system as claimed in claim 1, wherein said water drawn into said mains pressure water flow proceeds to a cold water outlet on the premises.

3. A system as claimed in claim I or 2, wherein said water drawn into said mains pressure water flow proceeds to the cold water inlet to said storage tank.

4. A system as claimed in claim 1, wherein said mains pressure water flow which enters said venturi has come from the hot water outlet of said storage tank, and proceeds to a hot water outlet on the premises.

5. A system as claimed in any one of the preceding claims wherein between said collection tank and said venturi there is included a valve means.

6. A system as claimed in claim 5, wherein said valve is controlled so that once a predetermined amount of relieved water is located in said collection tank said valve will open, allowing said relieved water to pass into said venturi.

7. A system as claimed in any one of the preceding claims, wherein a one way valve is located between said collection tank and said venturi.

8. A system as claimed in any one of the preceding claims, wherein said vent includes restriction means to prevent or limit the ingress of contaminants such as bacteria, viruses, germs etc.

9. A system as claimed in claim 8 wherein said restriction means can include one or more of the following: a filter; flow trap.

10. A system as claimed in any one of the preceding claims wherein said vent includes a vent valve means whereby when said relief valve opens, the vent valve also opens and vents the collection tank to atmosphere. 7

11. A system as claimed in claim 10, wherein said vent valve opens when said relief valve opens and closes when said relief valve closes, by means of one or more of the following: mechanical coupling; electrical and or solenoid coupling; hydraulic coupling.

12. A system as claimed in any one of claims 1 to 11, wherein there is included a bypass around the venturi, so that when high flow rates are required from the mains pressure water flow passing through the venturi, the bypass will allow the higher flow rates.

13. A method of re-using expelled water from a water heating system, said method comprising the steps of: a) receiving relieved water from an over-temperature and or over-pressure relief valve into liquid collection tank; b) passing a mains pressure water flow through a venturi, allowing said venturi to draw said relieved water from said collection tank.

14. A method as claimed in claim 13, further including the step of passing the mains pressure water flow and combined relieved water to a cold water outlet.

15. A method as claimed in claim 14, wherein said cold water outlet is the cold water inlet to said water heating system.

16. A method as claimed in claim 13, further including the step of providing the mains pressure water flow from the hot water outlet from said water heating system and passing the combined mains pressure water flow and combined relieved water to a hot water outlet.

17. A method as claimed in any one of claims 13 to 15, including the step of providing said collection tank with a vent to atmosphere.

18. A method as claimed in claim 17, wherein said vent includes a restriction means to preventing ingress of contaminants, such as dust, bacteria, viruses, etc.

19. A water heater expelled water re-use system as hereinbefore described with reference to the accompanying figure.

20. A method of re-using expelled water from a water heating system as hereinbefore described with reference to the accompanying drawing.

21. A water heating system having a water heater expelled water re-use system as claimed in any one of claims I to 11 or 19, or which utilises the method claimed in any one of claims 13 to 17 or 20. EDITORIAL NOTE APPLICATION NUMBER - 2004240166 This specification does not contain a page(s) "8" (to "8").