GB2449550A

GB2449550A - Water conservation system

Info

Publication number: GB2449550A
Application number: GB0809282A
Authority: GB
Inventors: Terrence Halsey Clark
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-05-22
Filing date: 2008-05-22
Publication date: 2008-11-26
Anticipated expiration: 2028-05-22
Also published as: GB0709787D0; GB2449550B; GB0809282D0

Abstract

The system 1, for use with a hot water supply system, includes a diverting means 3 for automatically drawing off a volume of water from the supply system upon demand from a user. The volume is diverted to one or more storage reservoirs 4 for subsequent use. The diverting means 3 may include a motorized valve 5 operable by a timer 6. The diverting means may be switched off when a predetermined criterion is met such as an average water temperature, a preset time or a predetermined volume of water. The system may be installed in a domestic dwelling 2 with the storage reservoir 4 disposed in the roof space 16 of the dwelling. Alternatively, the storage reservoirs may be disposed externally of the dwelling and may be below ground level.

Description

A Water Conservation System

Background

This invention relates to water conservation and is particularly concerned with avoiding wastage of water from domestic hot water supply systems.

In such systems, when significant non-use takes place, as, for example overnight, a volume of the water in the system falls in temperature. It is then usual for this cooler water to be drained off; so that a heated water supply becomes available once pipework (between a hot water storage tank or boiler and a tap) has been heated to the desired water temperature.

What usually occurs is that this cooler water is used to warm' pipework and allowed to drain away through a waste pipe. This is very wasteful of water and the present invention seeks to at least reduce such waste.

Prior Art

Published UK Patent Application GB 2 430 995 (Water-Miser) describes a water saving device for use in a hot water system to recover an initial volume of cold water when a hot water tap is turned on. The device has an inlet for receiving water piped from a water heater, a primary outlet for delivering hot water to a tap, and a by-pass outlet through which any cooled water is diverted by a thermally actuated shuttle valve.

The device also includes a secondary valve for closing off the by-pass outlet when the water pressure downstream of the primary outlet is high (such as when the down stream hot water delivery tap is closed) and opening the by pass outlet when the water pressure downstream of the primary outlet is low (such as when the downstream hot water delivery tap is opened.

Published UK Patent Application GB 2 309 731 (Eaves) describes a tap that includes a body having an inlet or primary fluid passage and an outlet interconnected via a tap valve and tap valve seat. The tap is characterised by the provision of a secondary fluid passage and an auxiliary valve is located in the secondary fluid passage; the secondary fluid passage communicating with the primary fluid passage at a juncture sufficiently close to the tap valve seat that a significant proportion of the fluid flowing under pressure to the opened tap will, when the auxiliary valve is opened, tend to be drawn into the secondary passage and through the auxiliary valve and then either to drain or to a storage facility other than the tap itself.

Neither the aforementioned systems discloses an arrangement that overcomes the waste of cooler water, which has heretofore been allowed to drain away, whilst pipework is heated or whilst a boiler is ignited and heats up pipework and any ancillary heat exchanger.

Summary of Invention

According to a first aspect of the invention, water conservation system includes a reservoir, which is adapted to be used with a hot water supply system; a diverting means which diverts a volume of water from the hot water supply system to the reservoir upon demand by a user; and means to switch the diverting means off, when a predetermined criterion is met.

Ideally the diversion of cooler water takes places automatically and when the predetermined criterion is met, hot water is permitted to flow from the hot water supply to a user, typically through a tap or faucet.

The predetermined citerion includes one or more of the following: a predetermined volume of water, a preset time whilst water is flowing, an average water temperature, and a predetermined volume of gas or oil, for example, used to heat the water by a gas or oil boiler.

The means for drawing off, or diverting, the water preferably comprises a motorised valve operable by a timer or by temperature control or under control of a sensor or microprocessor.

As used herein the term "motorised valve" includes a valve operable by a solenoid.

In an alternative embodiment an absolute volumetric measurement device may be used to measure a pre-set volume of water.

Ideally water stored in the reservoir is recirculated to a header tank. Altematievly water may be used as a supply to other household appliances, such as lavatories (water closets), central heang header tanks, cisterns, washing machines, irrigaon systems for plants or, subject to the header tank meeting water purity levels, even a potable supply of ewater for drinking.

Preferred embodiments of the invention will now be described, with reference to the Figures, in which:

Brief Description of the Figures.

Figure 1 illustrates a diagrammatical view of part of a hot water system supplying hot water both to a kitchen sink and to a washing machine, Figure 2 illustrates a diagrammatical view of another part of the system, which includes a water reservoir disposed in the roof space of a domestic building, Figure 3 is a side view which illustrates a modification of the system shown by Figure 1, Figure 4 is a side view of another modification, employing external water storage reservoirs, and Figure 5 is a schematic view of a system including reservoirs external to the dwelling, one olated one from the other.

Detailed description of the preferred embodiments.

Referring to the Figures, and with reference to Figures 1 and 2, there is shown a hot water supply system 1 installed in a domestic dwelling 2. System 1 is provided with means 3 for automatically drawing off a material or set volume of water from the system 1, and for transfemng the said volume to a storage reservoir 4 for subsequent use.

The means 3 for drawing off the metered volume of water comprises a motorised valve 5 operable by a timer 6. In an alternative embodiment an absolute volumetric measurement device may be used to measure a pre-set volume of water.

The hot water supply system I includes a sink 7 with hot water tap 8, a washing 20 machine 9 supplied by a branch line 10 of the system, and a hot water cylinder 15, typically disposed in the roof space 16 of dwelling 2. The discharge side 17 of the valve 5 leads to the reservoir 4, which is disposed in the roof space 16.

A large-bore overflow pipe 18 extends from the reservoir 4 to an extemal water collection system 19 (Figure 4), and a cold water tank 19 is also disposed in the roof space 16, a height H, above the reservoir 4. Cold water tank 19 is connected to the reservoir 4 by a gravity line 20.

The reservoir 4, which is supported in the roof space 16 by roof joists 21, has a low profile so as to become more easily accommodated in the roof space 16. A significant head of water pressure (H) exists between the reservoir 4 and the cold water tank 19 above.

In this example, timer 6 is set so that it operates three times a day, namely:-a) early morning, before the occupants of the dwelling 2 rise, say at 645am, b) after lunch, say about 3.45pm, and c) after dinner, say at 1 0.45pm.

Thus, for example at 06;45 the timer comes into operation to cause the motorised valve 5 to open whereby water reduced in temperate overnight flows through discharge line 17 to enter the storage reservoir 4. At 06.48 the timer 6 operates to close the valve 5.

It will be seen that between opening and closing of valve 5, a metered volume of the cooled water has been transferred to the storage reservoirs 4, for subsequent uses by way of a draw-off line 25.

The procedure is repeated, for example at 15:45 and at 22:45 and overall results in a substantial saving of water as it avoids the need to draw-off cooled water from the hot water line and pass it to a drain until the heated water supply is again available.

With reference to Figure 3, a modification is illustrated wherein the motorised valve 5 of Figure 1 is replaced by a solenoid valve 26 under the control of a timer 27. In an alternative a thermostatic controller could be used to control the valve. The discharge side of the valve 26 is connected to the reservoir 4 by way of a line 28.

Water transferred from the hot water system to the reservoir may be used, for example, to supply water closet cisterns in the dwelling 2, or, as illustrated by Figure 4, to be used in the garden of the dwelling 14.30 As shown in Figure 4, the large-bore the overflow pipe 18 of Figure 2 is connected to a garden water supply station 30. The garden water supply station 30 comprises three water butts 31 disposed above the ground level 33, on concrete supports 32. The butts 31 are cascaded sop that one feeds another and have draw-off taps 33, and removable cors 34.

Water flows down pipe 18 under the influence of gravity. The butts 31 are interconnected by overflow connections 35 whereby, the overflow water enters the first butt 31, then, when full, excess water packs downwardly into the second butt 31. When this is full, excess water passes downwardly into the third butt 31 in line. Station 30 thus provides a water cascade systems for the storage of 10 garden water supply.

Should water in the third butt 31 in line overflow, this is passed to an open drain 36 by way of an overflow pipe 37.

In a non-illustrated modification, the butts 31 may be disposed beneath ground level 33 and a pump used to transfer the collective water to above the ground.

Figure 5 is an alternative embodiment of the water conservation system 100. An outer wall 101 of a dwelling 102 is shown in diagrammatical form only. Cold water header tank 103 is depicted as being above a reservoir 104. Reservoir 104 is sealed by a breathable lid or cover 105. An overflow 106 is provided in the event of inadvertent build up of water in the reservoir 105. Overflow 106 feeds directly into a series of cascaded water butts 107, 108 and 109.

Operation of the system will now be described: water flows from the header tank 103 into a water heater such as an immersion heater 130 or boiler suitable for receiving a gravity feed supply. Other water heaters, such as so-called combi boilers' operate according to an alternative design as they receive a water supply directly from a cold mains supply or header'.

Upon demand by a user, for example at a sink (not shown) on a cold day after water in pipework 150 has been allowed to stand and cool, there is a delay or latency between demanding hot water (turning on a tap) and the hot water being dispensed.

This colder water is automatically diverted by way of automatic valve 140 to the sealed reservoir tank 105. Valve 140 operates under control of a control means such as a thermostat 145. When a preset criterion is met, for example an ideal water is reached, thermostat 145 switches valve 130 and water is diverted to a sink, shower or bath (not shown).

Isolation valves are provided in order to isolate individual reservoirs, tanks and supply in the event of a need to repair or replace any piece of equipment or in the event of flood or other need to isolate reservoirs or tanks from a potentially tainted water supply, thus providing, for example an emergency water supply of potable water.

Isolation valves 110 a and 110b are provided on the in feed (mains supply) of cold water feeder tank 103. Isolation valves 112a and 112b are provided on the in feed out flow line of cold water tank 103. Isolation valve 114a is provided on the in line of reservoir tank 104. Isolation valve 1 16b is provided on out flow of reservoir 104.

It is estimated that in a typical family house, where four people demand hot water twice each per day, that around 2 litres of water are wasted each time the hot water is allowed to drain, before it reaches a desired temperature. This approximates to around 5600 litres of wasted water per year. This water is, under hydrostatic pressure of the gravity feed tank 103 fed to reservoir tank 104 until a predetermined criterion is met, for example as sensed by thermostatic sensor 145. Sensor 145 controls valve 140 which then diverts hot water, from a hot water supply, such as an immersion heater 130, to a sink or shower (not shown).

Water from the reservoir 103 can be supplied to the immersion heater, or used to flush lavatories (water closets) or transferred to water butts 107 -109.

It will be appreciated that the invention has been described, by way of example only, and variation may be made top the embodiments described without departing from the scope of invention. For example a direct feed from rooves andlor gutters may be fed into one or more of the water butts so that all additional fresh water is available for watering plants and crops. Optionally the last water butt in the cascaded series may have an overflow that allows water to drain away to prevent inadvertent flooding in the event of heavy rainfall.

Claims

Claims 1. A water conservation system includes: a reservoir, which is

adapted to be used with a hot water supply system; a diverting means, which diverts a volume of water from the hot water supply system to the reservoir upon demand by a user; and means to switch the diverting means off, when a predetermined crfterion is met.
2. A water conservation system according to claim 1 wherein a predeterminded criterion is fm the group comprising: a predetermined volume of water, a preset time whilst water is flowing, an average water temperature.
3. A system as claimed in Claim 1 or 2, wherein the means of drawing off the water comprise a motorised valve operable by a timer.
4 A system as claimed in Claim 3, wherein the means for drawing off the water comprise a motorised valve operable by a timer.
5. A system as claimed in any of Claims 1 to 4, installed in a domestic building.
6. A system as claimed in Claim 5, wherein a single storage reservoir is disposed in the roof space of the dwelling.
7. A system as claimed in Claim 6, provided with a cold water tank also disposed in the roof space of the dwelling, and disposed above said reservoir so as to produce a significant head of water pressure.
8. A system as claimed in Claim 5, wherein several storage reservoirs are disposed external of the dwelling.
9. A system as claimed in Claim 8 wherein said several strong reservoirs are disposed below ground level.
10. A system as claimed in Claim 8 or 9 wherein a direct feed from roofs and/or gutters may be fed into one or more of the water reservoirs.

II. A system as claimed in Claim 9, wherein overflowing water passed from one storage reservoir to another in a cascading manner.

12. A system as claimed in any of Claims 8 to 11 wherein an overflow is provided in at least one of the reservoirs to allow water to drain away to prevent inadvertent flooding in the event of heavy rainfall.
11. A hot water supply system substantially as hereinbefore described and with reference to the Figures.