GB2309479A

GB2309479A - System for preventing water pipework from damage by frost

Info

Publication number: GB2309479A
Application number: GB9601545A
Authority: GB
Inventors: George Evdemon
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-01-26
Filing date: 1996-01-26
Publication date: 1997-07-30
Anticipated expiration: 2016-01-26
Also published as: GB2309479B; GB9601545D0

Abstract

A water supply system for a building comprises a temperature sensor (12, 13) used to control operation of a shut-off valve (6) applied to an inlet (1) and a drain valve (7) applied to a drain outlet (10) of the system. If there is a predetermined fall in temperature, such as a fall below freezing point, the inlet (1) is shut-off and the drain outlet (10) is opened. There may also be a pressure sensor (17) which similarly closes the inlet (1) and opens the drain outlet (10) if there is a fall in pressure signifying leakage.

Description

Water suolv system for building.

This invention relates to a water supply system for a building.

During cold periods of the year, water pipes in cold parts of buildings can burst and cause considerable damage, due to freezing of water in the pipe.

Bursts can be prevented by shutting off the water supply at an inlet pipe, and then opening taps within the building in order to drain the system.

However, this is only effective if there is a person in the building who is able to take the necessary action and who is aware of the need for such action to be taken.

An object of the present invention is to provide automatic protection against bursting which does not require reliance on action being taken by a person in the building.

According to the invention there is provided a water supply system for a building having an inlet, a drain outlet, a flow control device and a temperature sensor, the device being operable to close the inlet and open the drain outlet in response to a predetermined fall in temperature.

With this arrangement, protection against bursting can be achieved automatically.

The predetermined fall in temperature may be a fall below freezing point or below a temperature closely above or below freezing point. The sensor may be adjustable so that the required fall in temperature can be preset as desired.

There may be a single sensor located in the coldest region of the building, such as the loft of a house, or in any other suitable position whether or not occupied by the water system. The sensor may also be incorporated in the water system or positioned in contact with or alongside a pipe or other component of the system. There may be multiple sensors whereby the system is responsive to the predetermined fall in temperature of any one, or the average of all sensors or any other arrangement.

The (or each) sensor may take any suitable form and thus may comprise a temperature sensitive resistor or semiconductor.

With regard to the flow control device this preferably comprises one or more electrical motorised valves although any other suitable device or combination of devices may be used.

In a preferred embodiment, an override device is provided to override the action of the flow control device. This may comprise a by-pass section with a manually operated valve along its length, arranged to by-pass closure of the inlet. Also there may be a manually operated valve to override opening of the drain outlet.

In one embodiment the flow control device comprises a shut off valve in the inlet and a release valve in the drain outlet and the drain outlet connects with the inlet downstream of the shut off valve. Alternatively, the drain outlet may be applied to a different part of the system. Thus, when the inlet feeds a header tank the drain outlet is preferably connected downstream of such tank.

The shut off valve and the drain outlet are preferably close to a main inlet of the building, although other arrangements are also possible. Thus, in the case of a house with a loft, the inlet and outlet may be within or close to the loft, whereby the flow control device acts to cut off supply to the loft and to empty the pipes and other parts of the water system (such as any tank etc.) in the loft. It is to be understood therefore that the cut off and drain functions need not be applied to an entire water system of a building but may be applied to only part e.g. part of the system in a region (such as a loft) exposed to cold temperature.

Once the flow control device has operated it may remain in this state until reset by manual intervention. Alternatively, the flow control device may automatically reset once the temperature detected by the sensor or sensors rises back to the pre-set value.

The water system may incorporate a water metering device and the flow control device may be wholly or partially combined with this.

Whilst the arrangement of the present invention described above can provide effective protection against freezing problems, it is possible that water leakage can still occur, for example, due to a burst occurring in a part of the system in a region which is not monitored by the temperature sensor, or as a consequence of failure of the temperature sensor to respond to cold temperature, or due to failure of a joint or valve in the water system. As a safeguard protection against this, preferably the flow control device is operatively connected to a pressure sensor so that the inlet is cut off and the drain outlet is opened when the pressure drops below a predetermined level signifying leakage of water from the system.

Thus, and in accordance with a further aspect of the present invention there is provided a water supply system for a building having an inlet, a drain outlet, a flow control device and a pressure sensor, the device being operable to close the inlet and open the drain outlet in response to a predetermined fall in water pressure in the system.

The pressure sensor may be operable at all times. Preferably however provision is made for deactuating the sensor during normal occupancy of the building so that it is not triggered by a fall in pressure due to normal usage of water supply. If desired provision may also be made for deactuating the above mentioned temperature sensor under similar circumstances.

The invention will now be described further by way of example only and with reference to the accompanying drawings in which: Fig. 1 is a diagrammatic view of one form of a water supply system incorporating a flow control device in accordance with the present invention; Fig. 2 is a diagrammatic view showing the flow control device in more detail; Fig. 3 is a view similar to Fig. 2 of an alternative embodiment.

Fig. 1 shows a water supply system of a domestic residence. Water enters the building at a main inlet 1 which is provided with the usual stop cock 2, and this inlet 1 feeds a cold water header tank 3 in a loft 4 of the building via a ball-cock type valve which maintains a constant head of water in the tank 3.

The tank 3 has an outlet 5 which feeds the water system of the building and is connected to various taps, a hot water boiler and other equipment in different rooms of the building.

Adjacent to the main inlet 1, as shown in Fig. 2, there is a flow control device which consists of a shut off valve 6 in the main inlet on the downstream side of the stop cock 2, and a drain valve 7 in a drain pipe 8 which is connected between a nearby pipe 9 of the system and a nearby discharge outlet 10.

The nearby system pipe 9 may be any pipe receiving water from the header tank 3 and thus for example may be a pipe leading to a nearby tap.

The discharge outlet 10 may be connected to an existing discharge outlet e.g. a sink outlet or soil pipe, or it may be a separate outlet which, for example, is passed through a wall of the house and terminates over a grid or other convenient position.

The drain valve 7 and the shut off valve 6 are electrically-operated motorised valves and are connected to an electrical control unit 11. Within the loft 4 there are positioned two temperature sensors 12, 13 which may be thermistors or other devices and there are also connected to the control unit 11.

As shown in Fig. 2, there is by-pass pipe 14 connected across the shut off valve 6 in the main inlet pipe 1 and this is controlled by a manual valve 15.

The electrical control unit 11 is powered from mains supply (and/or batteries if desired) and incorporates an adjustment device for pre-selection of a desired temperature.

In use, a temperature at or near freezing point is selected and the control unit 11 is set in operational mode.

When the temperature in the loft 4, as monitored by the sensors 12, 13 is above the pre-selected temperature, the drain valve 7 remains closed, and the shut off valve 6 is open. The manual valve 15 is normally set closed.

In this condition, water enters the system, the header tank 3 fills, and water is fed through the building to the usual water equipment.

In the event that the temperature in the loft 4 falls to the pre-selected temperature this causes the control unit 11 to actuate the motorised valves 6, 7 so that the drain valve 7 opens and the shut off valve 6 closes. This prevents any further water being fed to the header tank 3 and water in the header tank 3 and also the entire system above the level of the drain outlet 10 is drained and discharged. Bursting due to freezing and consequent water damage can now be avoided.

If desired, and as shown in broken lines in Fig. 2, there may be a link 16 between the inlet pipe 1, on the downwater side of the shut off valve 2, and the drain valve, so that, when the drain valve 7 opens, the inlet pipe 1 within the building is also drained.

The by pass pipe 14 and manual valve 1 5 provides means for manually by-passing the shut off valve 6 should this be required and the drain valve 7 may also be manually closeable.

As indicated in Fig. 1, a pressure sensor 17 may be associated with the header tank 3 or with an outlet pipe thereof; such sensor 17 being connected to the control unit 11. A switch is provided on the control unit 11 for actuating the pressure sensor 17 and this may be done when the building is intended to be unoccupied. In the event that the pressure sensor 17 detects a drop in pressure in the water system, this triggers closing of the shut off valve 6 and opening of the drain valve 7 as discussed above.

After closure of the shut off valve 6 and opening of the drain valve 7, the system may automatically revert to the normal operational state after normal conditions (i.e normal temperature and pressure) return.

Alternatively, and especially in the case where action has been initiated by the pressure sensor 17, it may be necessary to operate a switch on the control unit 11 or otherwise initiate appropriate action, and the need for this may be signalled by an alarm light on the control unit 11 or otherwise.

It is of course to be understood that the invention is not intended to be restricted to details of the above embodiment which are described by way of example only.

Thus, for example, the flow control device is not restricted to use with a header-tank type system. It may alternatively be used with a closed pressured system in which case the drain outlet will be connected to the inlet pipe as shown in Fig. 3.

Claims

1. A water supply system for a building having an inlet, a drain outlet, a flow control device and a temperature sensor, the device being operable to close the inlet and open the drain outlet in response to a predetermined fall in temperature.

2. A system according to claim 1 wherein the predetermined fall in temperature constitutes a fall below freezing point.

3. A system according to claim 1 or 2 wherein the sensor is located within an air space within the building so as to be responsive to the air temperature.

4. A system according to claim 3 wherein the air space is within the loft of a house.

5. A system according to claim 1 or 2 wherein the sensor is incorporated in the water system so as to be responsive to the water temperature.

6. A system according to any one of claims 1 to 5 wherein the flow control device comprises one or more electrical motorised valves.

7. A system according to any one of claims 1 to 6 wherein an override device is provided to override the action of the flow control device.

8. A system according to claim 7 wherein the override device comprises a by-pass section with a manually operated valve arranged to bypass closure of the inlet.

9. A system according to any one of claims 1 to 8 further including a manually operated valve to override opening of the drain outlet.

10. A system according to any one of claims 1 to 9 wherein the flow control device comprises a shut off valve in the inlet and a release valve in the drain outlet, and the drain outlet connects with the inlet downstream of the shut-off valve.

11. A system according to any one of claims 1 to 9 having a header tank and wherein the flow control device comprises a shut off valve in the inlet and the drain outlet is connected downstream of the header tank.

12. A system according to any one of claims 1 to 11, wherein the inlet and outlet are within a part of the building and the flow control device acts to cut off supply to that part of the building.

13. A system according to claim 12 wherein the said part of the building is a loft of a house.

14. A system according to any one of claims 1 to 13 wherein the flow control device is arranged automatically to reset once the temperature rises back to a pre-set value.

15. A system according to any one of claims 1 to 14 wherein the flow control device is solely responsive to temperature.

16. A system according to any one of claims 1 to 14 wherein the flow control device is additionally responsive to pressure whereby the device is operable to close the inlet and open the drain outlet in response to a predetermined fall in pressure.

17. A water supply system for a building having an inlet, a drain outlet, a flow control device and a pressure sensor, the device being operable to close the inlet and open the drain outlet in response to a predetermined fall in water pressure in the system.

18. A water supply system substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.