AU2006202589B2

AU2006202589B2 - Supplementary water supply system

Info

Publication number: AU2006202589B2
Application number: AU2006202589A
Authority: AU
Inventors: Alan Boyes; John Wise
Original assignee: SILVAN H2O Pty Ltd
Current assignee: SILVAN H2O Pty Ltd
Priority date: 2005-05-20
Filing date: 2006-06-20
Publication date: 2009-06-18
Anticipated expiration: 2026-05-20
Also published as: AU2006202589A1

Description

AUSTRALIA Patents Act 1990 Silvan H20 Pty Ltd COMPLETE SPECIFICATION Invention Title: Supplementary Water Supply System The invention is described in the following statement: 2 Supplementary Water Supply System Field of the Invention This invention relates to a supplementary water supply system and relates 5 particularly to a water supply system that is able to use rain water, waste water or some other form of alternative water supply to supplement a reticulated water supply. Background of the Invention Supplementary water supply systems are most desirable where water is scarce, 10 supplies are unreliable and/or expensive. Water conservation is becoming increasingly important to ensure sustainable supplies of potable water and many proposals have been made to provide supplementary supplies. A most common proposal for a supplementary water supply is to utilise rain water collected in a container or tank. Where it is inappropriate to filter and/or purify 15 such water, it is often used for purposes other than drinking, such as for flushing toilets, watering gardens and lawns, clothes washing and the like. In many proposals, a supplementary water system involves the use of a tank which is topped up, or maintained at a predetermined minimum level, with water from a reticulated town supply or other mains supply. This ensures that the supplementary supply system 20 always has water available for the purpose for which it is installed and obviates the need for a change-over valve or the like in the event the supplementary water tank runs dry. The tank may be located in a roof cavity to provide gravity feed to the outlet. Alternatively, a pump may be used to supply water to the tank outlet. In this case, the pump is operated whenever a demand for water is determined. 25 A disadvantage of such a system is that the tank which is topped up from the mains water supply (town water) is unable to take advantage of all rainfall that may occur in a particular period due to at least part of the tank containing town water. Further, where such a system relies on a pump to pump the water to the outlet, in the event of a power failure, the water supply to that outlet fails. Further, the pump is 30 required to deliver water whenever there is demand, thus adding to the cost of operation of the system. The connection of a mains water supply (town water) to a supplementary supply system must comply with regulations of various water authorities to ensure that there is no contamination of the town water by the supplementary water. 35 It is therefore desirable to provide a supplementing water system which avoids disadvantages of previously proposed supplementary supply systems. m:\specifications\500000\504000\504563capdcc.doc 3 It is also desirable to provide a supplementing water supply system which complies with the regulations of the water supply authorities. It is also desirable to provide a supplementing water supply system which is relatively economical, is simple to construct and which is efficient in operation. 5 It is also desirable to provide a water supply system which is able to provide water to the system outlet at all times. It is also desirable to provide a water supply system which is able to use rain water, grey water or any other waste water suitable for reuse. 10 Summary of the Invention In accordance with one aspect of the invention there is provided a water supply system to supplement a mains water supply and including: demand means detecting a demand for water; status means detecting the presence of supplementing water at or above a 15 predetermined amount; delivery means to deliver supplementing water; actuating means to actuate the delivering means in response to both detecting a demand for water and the status means detecting the presence of supplementing water at or above said predetermined amount; and 20 valve means blocking said mains water supply until said status means detects less than said predetermined amount of supplementing water, wherein said valve means comprises a normally closed solenoid valve in the mains water supply line which, when a demand for water is detected, is held in the open position by a signal from the control unit when the status means detects less than 25 said predetermined amount of supplementing water, but is allowed to close when the status means detects greater than said predetermined amount of supplementing water. According to a further aspect of the invention there is provided a method of supplementing a mains water supply including the steps of detecting a demand for water; 30 detecting the presence of supplementing water at or above a predetermined amount; actuating delivery means to deliver supplementary water in response to detecting a demand for water and the status means detecting the presence of supplementing water at or above a predetermined minimum; and 35 3a blocking said mains water supply with a valve means until the status means detects less than said predetermined minimum. The demand means for detecting a demand for water may include a pressure switch or a flow sensor. The pressure switch or flow sensor will preferably provide a 5 signal to a control unit to provide an indication of the water demand. The status means may be any means suitable for detecting water or a water level in, for example, a storage tank or the like. One such status means may include a float 4 valve mounted in a storage tank. Another status means may be a pressure switch or sensor measuring the pressure of water at or adjacent the bottom of a container which provides an indication of water depth and, therefore, quantity. However, many other forms of means for detecting the presence of water and/or a level of water are well 5 known and any such detection or level sensing means may be used in the performance of the invention. The delivering means is preferably a pump associated with the supplementing water and able to deliver the supplementing water to satisfy the demand. The pump, in a preferred form of the invention, is a submersible pump located within a water storage 10 tank. However, the pump may be any suitable pump able to draw water from the storage tank, or other supplementing water supply. The actuating means preferably comprises a control unit which receives the demand signal and which also is adapted to receive a signal from the status means. In response to the demand signal and the presence or absence of a status signal, the 15 control unit actuates the pump. However, pump actuation only occurs if the signal, or absence of signal, from the status means provides an indication of the presence of supplementing water at or above a predetermined amount. The valve means preferably comprises a normally open solenoid valve in the mains water supply line which is held in the closed position by a signal from the 20 control unit until the status means detects less than said predetermined amount of water. Thus, the solenoid valve is normally held closed but is moved to the open position and is able to satisfy a demand from the mains supply in the event that a demand signal is received by the control unit but the status means indicates an insufficient supply of supplementing water. In this case, the pump is not actuated. 25 In the event that the pump is actuated and, during operation, the water quantity falls below the predetermined minimum level, the status signal to the control unit will change state causing the pump to cease operating whereby the valve means will open so that the demand is satisfied from the mains water supply. The system of the present invention has a number of advantages in that pump 30 operation is minimised and control of the supplementing water supply is effected only when sufficient water is available. In accordance with another aspect of the present invention there is provided a water supply system to supplement a mains water supply including: demand means detecting a demand for water; 35 status means detecting the presence of supplementing water at or above a predetermined amount; m:\specifications\500000\504000\504563capdcc.doc 5 delivering means to deliver supplementing water; actuating means to actuate the delivering means in response to detecting a demand for water and the status means detecting the presence of supplementing water at or above said predetermined minimum; and 5 valve means adapted to be closed to block said mains water supply when the status means detects supplementing water at or above said predetermined amount, wherein said valve means comprises a normally closed solenoid valve in the mains water supply line which, when a demand for water is detected, is held in the open position by a signal from the control unit when the status means detects less than 10 said predetermined amount of supplementing water, but is allowed to close when the status means detects greater than said predetermined amount of supplementing water. With this arrangement, the demand is met by the supplementing water until the status means detects the supplementing water to be less than said predetermined amount at which time the valve means is caused to move to the normally open position. 15 This arrangement also ensures that, in the event of a power failure, the normally open solenoid valve allows mains water to supply any demand. In a variation of embodiments of the invention, the valve means comprises a normally closed solenoid valve in the mains water supply line. Such a normally closed valve is moved to the open position in the event that a demand signal is received by the 20 control unit but the status means indicates an insufficient supply of supplementing water. In this case, the pump is not actuated. According to a still further aspect of the invention there is provided a water supply system to supplement a mains water supply including: a valve in said mains water supply to control the flow of mains water to a 25 supply outlet, a supplementing water storage tank; a submersible pump in said tank connected to the supply outlet downstream of the valve; a pressure switch downstream of said pump and operable to provide an 30 indication when water pressure in the supply outlet is less than a predetermined value; a one-way valve downstream of said pump preventing water flow to the pump from the mains water supply; supplementing water status means detecting when the amount of water in said tank is greater or less than a predetermined minimum; 6 a control unit to control operation of said pump on receipt of a water demand indication from said pressure switch and when the status means detects water in the tank greater than said predetermined minimum; said control unit causing actuation of said valve to admit mains water to the 5 supply outlet and terminating pump operation when the status means detects water in the tank less than said predetermined minimum. In order that the invention is more readily understood, embodiment thereof will now be described with reference to the accompanying drawing. Any discussion of documents, acts, materials, devices, articles or the like which 10 has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application. 15 Description of the Drawings Figure 1 schematically illustrates an embodiment of a water supply system in accordance with the invention. Figure 2 schematically illustrates a further embodiment of a water supply 20 system in accordance with the invention. Description of the Preferred Embodiments The water supply system shown in Figure 1 includes a storage tank 12 having an inlet 14. Supplementing water, such as rain water from a roof, or grey water, or 25 other reusable waste water is supplied to the tank 12 through the inlet 14. A simple float valve 16 is mounted in the tank 12 and is connected to a valve switch 17 which is set to provide a signal to a control unit 18 when the valve switch 17 is actuated. The signal indicates that the water level in the tank 12 is at or above a predetermined amount. Alternatively, the signal may indicate that the water level is 30 below said predetermined amount. In a further modification, the control unit 18 may poll the valve switch 17 to check its status, in a known manner. A submersible delivery pump 19 is located in the storage tank 12, the pump 19, when operating, delivering water through the outlet pipe 21 to a T piece 22. A pressure 6a switch 23 is mounted on the outlet part 21 and provides a signal to the control unit 18 when pressure in the outlet pipe 21 drops to a predetermined level, indicating a demand for water by a consumer. The T piece 22 is connected to the consumer outlet 24 while the other side of the T piece 22 is connected to the mains supply 26 through a normally 5 open, solenoid operated valve 27 and a non-return valve 28. The non-return valve 28 prevents contamination of the mains water supply by preventing flow of water in the direction towards the mains supply inlet. The normally open solenoid valve 27 is held in a closed position by a signal from the control unit. 10 In operation, when a demand for water exists at the consumer outlet 24, the pressure switch 23 will register the demand and signal the control unit 18 accordingly. The control unit 18, either being in receipt of a signal from the float valve switch 17, or interrogating that switch for its status, will actuate the pump 19 if the float valve is in a 7 position indicating supplementing water in the tank 12 above a predetermined level. The pump 19, therefore supplies demand to the consumer outlet 24. The normally closed solenoid valve 27 remains held in the closed condition so mains water from the supply 26 is not used to satisfy the consumer demand. 5 In the event that the float valve 16 indicates a level of water in the tank 12 below a predetermined minimum, the valve switch 17 provides the appropriate indication to the control unit 18 whereby the control unit 18 causes the closed solenoid valve 27 to open thereby satisfy demand from the mains supply 26. When a demand is satisfied, pressure in the consumer outlet 24 increases 10 thereby actuating the pressure switch 23 which signals the control unit to cease operating the pump 19, if the pump has been operated to satisfy the demand . If there is no supplementing water in the system, the valve 27 remains open. If desired, a pressure reducing valve may be included in the mains supply line 26, such as between the non-return valve 28 and the solenoid valve 27. 15 A non-return valve 31 may also be included in the pump outlet pipe 21 to ensure mains pressure water does not flow through the pump into the tank 12 when the solenoid valve 27 is open. Such a non-return valve 31 may be a separate valve, as shown, or may be incorporated into the pressure switch 23. In a further embodiment of the invention shown in Figure 2, the solenoid valve 20 127 is a normally closed solenoid valve. With this arrangement, when a consumer demand is sensed, and the float valve 116 is in a position to indicate the presence of supplementing water in the tank 112 above the predetermined level, the control unit 118 initiates operation of the pump 119 to supply the consumer demand, and the valve 127 remains closed. When the demand has been met, and the water pressure in the 25 consumer outlet 124 increases, the pressure switch 123 signals the control unit 118 which shuts off the pump 119 If, however, insufficient water is available in the tank 112, instead of operating the pump 119, the control unit 118 causes the solenoid valve 127 to open to supply the demand from the mains supply.. With this modified arrangement, a battery backup 132 may be provided to open 30 the solenoid valve 127 in the event of a power failure, so that water is supplied to the consumer outlet 124 from the mains supply 126. As in the previous embodiment, a non-return valve 131 may also be included in the pump outlet pipe 121 to ensure mains pressure water does not flow through the pump into the tank 112 when the solenoid valve 127 is open. Such a non-return valve 35 131 may be a separate valve, as shown, or may be incorporated into the pressure switch 123 m:\specifications\500000\504000\504563capdcc.doc 8 It will be seen that the control of the pump and the solenoid valve is under the influence of the float valve 116 and associated switch 117 which provides an indication of the presence of sufficient supplementing water in the tank 112. As indicated above, other means of detecting the presence of sufficient water in the tank may be used in the 5 performance of this invention. It will also be appreciated that, during operation of the system in any of its embodiments, when the pump 19, 119 is supplying demand, if the water level in the tank drops to or below the predetermined level or amount, the control unit 18, 118 will cause the solenoid valve 27,127 to open and shut down the pump operation so that a 10 substantially seamless change to mains water supplying the demand occurs It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as 15 illustrative and not restrictive. m:\specifications\500000\504000\504563capdcc.doc

Claims

1. A water supply system to supplement a mains water supply and including: demand means detecting a demand for water; status means detecting the presence of supplementing water at or above a predetermined amount; 5 delivery means to deliver supplementing water; actuating means to actuate the delivering means in response to both detecting a demand for water and the status means detecting the presence of supplementing water at or above said predetermined amount; and valve means blocking said mains water supply until said status means detects 10 less than said predetermined amount of supplementing water, wherein said valve means comprises a normally closed solenoid valve in the mains water supply line which, when a demand for water is detected, is held in the open position by a signal from the control unit when the status means detects less than said predetermined amount of supplementing water, but is allowed to close when the 15 status means detects greater than said predetermined amount of supplementing water.

2. A water supply system according to claim 1 wherein the demand means comprises a pressure switch. 20

3. A water supply system according to claim I wherein the demand means comprises a flow sensor.

4. A water supply system according to claim 2 or claim 3 wherein the demand means provides a signal to a control unit. 25

5. A water supply system according to any one of claims I to 4 wherein the status means comprises a float valve mounted in a storage tank.

6. A water supply system according to any one of claims I to 4 wherein the status 30 means comprises a pressure switch or sensor measuring the pressure of water at or adjacent the bottom of a storage tank to provides an indication of water depth and quantity. 10

7. A water supply system according to any one of claims I to 6 wherein the delivering means is a pump associated with the supplementing water and able to deliver the supplementing water to satisfy the demand. 5

8. A water supply system according to claim 7 wherein the pump is a submersible pump located within a water storage tank.

9. A water supply system according to any one of the preceding claims wherein the actuating means comprises a control unit which receives a demand signal and a signal 10 from the status means and in response thereto actuates the pump only when the status signal indicates the presence of supplementing water at or above said predetermined amount.

10. A water supply system according to claim 9 wherein the valve means comprises 15 a normally open solenoid valve in the mains water supply line which, when a demand for water is detected, is held in the closed position by a signal from the control unit until the status means detects less than said predetermined amount of supplementing water. 20

11. A water supply system according to claim 10 wherein a battery backup power supply connected to the control unit holds the normally closed valve in the open position in the event of a failure of normal power supply to the control unit and pump.

12. A water supply system to supplement a mains water supply including: 25 demand means detecting a demand for water; status means detecting the presence of supplementing water at or above a predetermined amount; delivering means to deliver supplementing water; actuating means to actuate the delivering means in response to detecting a 30 demand for water and the status means detecting the presence of supplementing water at or above said predetermined minimum; and valve means adapted to be closed to block said mains water supply when the status means detects supplementing water at or above said predetermined amount, wherein said valve means comprises a normally closed solenoid valve in the 35 mains water supply line which, when a demand for water is detected, is held in the open position by a signal from the control unit when the status means detects less than I I said predetermined amount of supplementing water, but is allowed to close when the status means detects greater than said predetermined amount of supplementing water.

13. A water supply system to supplement a mains water supply including: 5 a valve in said mains water supply to control the flow of mains water to a supply outlet, a supplementing water storage tank; a submersible pump in said tank connected to the supply outlet downstream of the valve; 10 a pressure switch downstream of said pump and operable to provide an indication when water pressure in the supply outlet is less than a predetermined value; a one-way valve downstream of said pump preventing water flow to the pump from the mains water supply; supplementing water status means detecting when the amount of water in said 15 tank is greater or less than a predetermined minimum; a control unit to control operation of said pump on receipt of a water demand indication from said pressure switch and when the status means detects water in the tank greater than said predetermined minimum; said control unit causing actuation of said valve to admit mains water to the 20 supply outlet and terminating pump operation when the status means detects water in the tank less than said predetermined minimum.

14. A method of supplementing a mains water supply including the steps of: detecting a demand for water; 25 detecting the presence of supplementing water at or above a predetermined amount; actuating delivery means to deliver supplementary water in response to both detecting a demand for water and detecting the presence of supplementing water at or above the predetermined minimum; and 30 blocking said mains water supply with a valve means until the presence of supplementing water is detected at or above the predetermined minimum.

15. A method of supplementing a mains water supply according to claim 14 wherein said step of detecting a demand for water includes the step of detecting a water pressure 35 in an outlet pipe. 12

16. A method of supplementing a mains water supply according to claim 14 or claim 15 including the step of measuring an amount of water in a supplementing water tank. 5

17. A method of supplementing a mains water supply according to any one of claims 14 to 15 including the steps of generating a signal in response to detecting the presence of supplementing water at or above a predetermined amount, and maintaining a normally open valve in a closed position until the presence of supplementing water is detected to be less than said predetermined minimum. 10

18. A method of supplementing a mains water supply according to any one of claims 14 to 15 including the steps of maintaining a normally closed valve in a closed position until the presence of supplementing water is detected to be less than said predetermined minimum at which time a valve open signal is generated to open said 15 valve at least when a demand for water is detected.

19. A method of supplementing a mains water supply according to any one of claims 14 to 18 wherein actuating said delivery means comprises operating a pump to pump supplementing water to satisfy the demand. 20

20. A method of supplementing a mains water supply having the steps substantially as hereinbefore described with reference to the accompanying drawings.

21. A water supply system to supplement a mains water supply substantially as 25 hereinbefore described with reference to the accompanying drawings.