GB2475323A

GB2475323A - Alarm system for an oil-fired heating system that monitors pressure in the fuel supply line

Info

Publication number: GB2475323A
Application number: GB0920028A
Authority: GB
Inventors: Alan Jackson
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-11-16
Filing date: 2009-11-16
Publication date: 2011-05-18
Anticipated expiration: 2029-11-16
Also published as: GB0920028D0; GB2475323B

Abstract

An alarm system monitors an oil-fired heating system comprising a fuel storage tank; a boiler; and fuel supply line extending between tank and boiler. The alarm system comprises a pressure sensor for detecting the pressure of oil in the supply line; a processor; and an alarm. The processor identifies normal pressure conditions during startup, normal operation, shut-down and rest of the boiler — ideally by analyzing pressure data generated during use of the heating system - and also activates the alarm when a change in pressure is detected that does not correspond to normal system operation. The sensor may monitor absolute pressure or changes therein. More generally, the system lnay monitor the condition of any pipeline and comprise a comparator that simply outputs a signal if the pressure differs from a value expected during normal operation.

Description

OIL TANK AND PIPELINE ALARM SYSTEM AND SYSTEM COMPRISING

THE SAME

The present invention relates to an alarm system for use with fluid-containing tanks, in particular for tanks containing liquid, such as oil for fuelling a boiler or the like, especially to a domestic oil-burning heating system. The present invention also relates to a heating system comprising the alarm system, especially a domestic oil-burning heating system. The present invention also relates, more generally, to a system for monitoring the components connected to a pipeline or pipeline system for carrying a fluid.

A significant number of buildings are heated by means of boilers burning a hydrocarbon fuel. Oil is a particularly common hydrocarbon fuel for such systems. In particular, a significant number of buildings in remote or semi-remote areas rely on the use of oil to power their heating systems. This is particularly the case with domestic properties in rural areas, where a connection to a mains gas supply is not available or feasible. A typical heating system installation employs a tank for storing the fuel oil, the tank being located outside the building, within the building or underground.

Increasingly, due to safety considerations, fuel oil tanks are being placed some distance from the building. The fuel oil tank is connected to the boiler, which may be within the building or outside, by means of a pipe. The siting of fuel oil tanks outside, and often some distance from, buildings raises a * S..

number of technical problems. *

*****.

First, the pipe connecting the fuel oil tank to the boiler is vulnerable to being damaged, resulting in the pipe and/or its connections leaking. This in turn results in a waste of valuable fuel oil, while also polluting the ground in the vicinity of the pipe and the tank.

Second, with increasing fuel prices, the theft of fuel oil from fuel oil tanks, in particular domestic fuel oil tanks, is increasing. Typically, thieves will not remove the entire contents of the fuel oil tank, but rather take a portion of the tank's contents, albeit a significant portion.

It is known and a generally common practice to provide a means for indicating the level of oil within a fuel oil tank. One simple system employs a transparent tube or sight glass extending vertically on the exterior of the tank.

The tube is connected at its lower end to the interior of the tank and the liquid level within the tank is visible within the tube. While simple, this system can only be viewed from close to the tank. In practice, such systems are very poor at providing an indication of the level in the tank and are used only infrequently by users. As a result, such systems are not suitable for the rapid detection of a leak or of theft of oil from the tank.

Alarm systems for domestic oil tanks are also known. One example of an alarm system comprises a sensor disposed to detect the level of oil in the tank and communicating, in particular wirelessly, with an indicator within the building. While such systems can be easier to use, in particular from inside the building, they can be unreliable.

One problem with existing level indicator and alarm systems is that, as they require some or all of their components to be mounted on the oil tank, ::.. 25 they can be tampered with by thieves and immobilised. Existing level indicator systems and alarm systems are also not capable of providing a rapid response and indication to a user about a leak or a theft, which typically results in a significant loss of oil before the user is made aware of the loss of oil. 30

IS

S S If

SG 153847 discloses a system for storing and dispensing liquids. The system comprises a pressure transducer to detect when a storing vessel is empty and a pump for dispensing the fluid. The system appears to be dedicated to the delivery in the small amounts of chemical reagents and compositions of high purity, such as liquid compositions for use in the mechanical polishing of microelectronic devices.

CN 201225962 concerns a test platform for an intelligent high voltage gas/liquid system having a control system connected to a computer interface for controlling a gas distribution platform. There appears to be nothing relating to the detection of a loss of oil from a fuel oil tank, in particular one in a domestic heating system.

CN 101138201 is directed to an intelligent measuring and counting system for use in an oil tank farm. The system appears to be particularly complex in its collection of data from a plurality of tanks and is unsuitable for use in a domestic heating system.

CN 201032546 discloses an anti-theft alarm system for an oil storage tank. The system comprises a remote controller, a monitor unit and an alarm display, all connected wirelessly. The system is installed on an oil storage tank in an oil field. The system appears to be vulnerable to being tampered with by a thief. *.. I * S *

* 25 An alarm device for an oil tank of a boiler is disclosed in d 055 KR 890003926.

I

**** S. * JP 2006084299 discloses an environmental pollution monitoring *5 5SS * system for use in a liquid supply facility and detecting the leakage of a liquid,

SI IS

30 in particular oil. The system comprises a leakage inspection tube disposed S. I) * S

S I

around an underground tank to detect an oil leak. The inspection tube is provided with a transmitter communicating with an alarm device.

CN 2221779 concerns a digital level indicator and alarm system for liquid storage equipment. The system comprises a rubber tube and a force transducer which communicates to a signal processing tank, having a sensing circuit, a digital display and an alarm.

Although a variety of systems have been proposed for detecting the loss of liquid in a variety of applications, there remains a need for an improved detection and alarm system addressing the aforementioned problems associated with oil-fired heating systems, in particular domestic oil-burning heating systems, as described above. More generally, there is a need for an improved system and method for monitoring a pipeline carrying fluids and the components connected to the pipeline, in particular to detect the occurrence of leaks in the pipeline or the associates equipment.

It has now been found that an improved and particularly advantageous system and method for monitoring the amount of oil in the tank of heating system is based upon measuring the oil in the line connecting the tank with the boiler, in particular by measuring the pressure of oil within the line and/or changes in the oil pressure and comparing the pressure so measured with the oil pressure expected during normal operation of the heating system. Should an oil pressure outside the values corresponding to normal operation be detected an alarm can then be sounded. * .** * * *

S * S.S

In a first aspect, the present invention provides an alarm system for an oil-fired heating system, the heating system comprising a tank for storing fuel oil, a boiler having a burner and a line extending between the tank and the boiler for supplying oil from the tank to the burner of the boiler, the alarm system comprising a pressure sensor for detecting the pressure of oil within the line; a processor for receiving signals from the pressure sensor and arranged to identify the normal pressure conditions of oil in the line during start-up, normal operation, shut-down and rest of the boiler; and an alarm operable in response to a signal received from the processor, in use the processor activating the alarm when a change in pressure of oil in the line is detected that does not correspond to normal operation of the heating system.

In a further aspect, the present invention provides a heating system, in particular a domestic heating system, comprising a boiler having a burner arranged to burn fuel oil; a tank for holding fuel oil; a line connecting the tank to the burner of the boiler; a pressure sensor arranged to measure the pressure of oil in the line; a processor for receiving signals from the pressure sensor and arranged to identify the normal pressure conditions of oil in the line during start-up, normal operation, shut-down and rest of the boiler; and an alarm operable in response to a signal received from the processor; in operation the processor activating the alarm when a change in the pressure of oil in the line is detected that does not correspond to normal operation of the heating system.

In a still further aspect, the present invention provides a method of operating a heating system, in particular a domestic heating system, the system comprising a boiler having a burner for burning fuel oil; a tank for holding fuel oil; and a line extending between the tank and the burner for supplying oil from the tank to the burner; the method comprising measuring the pressure of oil in the line; determining the pressure of oil in the line during .. : normal operation of the boiler; identifying when the pressure of oil in the line * S falls outside the range of pressures corresponding to normal operation of the * boiler and in such events activating an alarm. * 5 *

* S....

* 30 The systems and method of the present invention provide an improved monitoring of the fuel oil in the tank and can readily identify a wide range of unusual conditions, including the rapid removal of oil from the tank, for example as a result of theft, or a leak in the heating system, such as a split or fractured line, a leaking joint or valve, a leak within the burner of the boiler, or the like. As indicated, the systems and method are particularly suitable for use in a domestic heating system, where protection against such events as theft of oil or a leak can be provided in a simple and reliable manner.

The heating system, for example of a domestic building, will be well known to persons skilled in the art and can be considered to generally comprise a tank for holding fuel oil, a boiler having a burner for burning fuel oil and a line for feeding oil from the tank to the burner of the boiler. The heating system may comprise one or more valves in the line between the tank and the boiler. In particular, the system will generally comprise a valve on or close to the tank for regulating the flow of oil through the line, especially allowing the line to be isolated for the tank, for example for replacement or repair. In addition, many systems are provided with a further valve in the line which is activated automatically in the event of a fire to close the line and shut-off the flow of oil to the boiler.

The systems and method of the present invention rely on the measurement of the pressure of oil in the line between the tank and the burner of the boiler, or more particularly, in detecting changes in the pressure of the oil in the line. To achieve this, the systems employ a pressure sensor for detecting the pressure of oil in the line. The pressure sensor may be any suitable means for measuring the pressure or changes in pressure of oil in the : line. A pressure transducer is one preferred sensor. Suitable pressure sensors are known and are commercially available.

* .S*' * The pressure sensor may be located at any suitable position in the line between the tank and the boiler. Preferably, the pressure sensor is located in the portion of the line adjacent the burner. If one or more valves are present in the line between the tank and the burner, the pressure sensor is most preferably disposed in the line between the one or more valves and the burner. More preferably, the pressure sensor is located at the junction between the line and the boiler or as close as practicable thereto. If the boiler is located within the building, the pressure sensor is most preferably located in a portion of the line within the building. In this way, the opportunities for the pressure sensor to be tampered with, for example by thieves, is removed.

As mentioned hereinbefore, the pressure sensor may be arranged to determine the actual pressure of the oil within the line. Alternatively, the pressure sensor may simply be arranged to respond to changes in the pressure of the oil within the line.

In operation, the pressure sensor generates a signal corresponding to the pressure of oil within the line. The signal is sent by the pressure sensor to a processor. Communication between the pressure sensor and the processor may be by any suitable means, for example by means of a cable.

Alternatively, the communication may be wireless. Suitable means for providing communication between the pressure sensor and the processor are known and are commercially available.

The processor of the systems of the present invention receives and acts upon signals received from the pressure sensor. The processor is arranged to identify the normal operating conditions of the heating system.

Thus, the processor is able to identify the signals generated by the pressure : sensor during the normal operating cycles of the boiler and its burner. The * *.* I""' normal operation of the boiler will include a start-up period, during which the 1 P burner is ignited, a shut-down period, during the burner is extinguished, periods of constant operation, during which the burner is operating in a substantially steady state or constant mode, and periods of rest, during which the burner is not ignited. As will be appreciated, the demand of the boiler for oil during these different phases of operation will vary, in turn causing the pressure of oil within the line to vary in a corresponding manner.

The processor is arranged to receive signals from the pressure sensor during all of the aforementioned phases of operation of the boiler. In one embodiment, the processor is an analogue comparator, that is able to compare the signals received from the pressure sensor with conditions of normal operation. Alternatively, the processor may comprise a microprocessor or the like, including means for receiving data signals from the pressure sensor, means for processing the signals, in particular to generate a profile of normal operation of the system, memory means for storing data, and means for comparing the signals received from the pressure sensor during operation with data retrieved from the memory.

In one embodiment, the processor is an analogue device or comparator for measuring the pressure of fluid within the line. The comparator may have two separate circuits having different response times to changes in pressure within the line. The first circuit tracks and responds to slow changes in pressure expected during the normal operation of the system, such as the gradual reduction in pressure as the volume of liquid in the tank reduces over time. The first circuit is arranged not to react to fast changes in the pressure.

The output of the first circuit is used as a reference pressure. The second circuit is arranged to respond to more rapid changes in pressure in the line, such as will occur when the line or the tank is split or ruptured. The output of second circuit is compared continuously with that of the first circuit. Should S...

the difference in output of the two circuits exceed a predetermined threshold value, the comparator outputs a signal, for example to trigger an alarm system. 55.55

* 30 In an alternative embodiment, the processor is a digital device or :. microprocessor, arranged to digitally sample the pressure of liquid within the line at predetermined sampling periods. The output of the digital sampling is compared with the previous readings taken by the microprocessor. Should the pressure change in the line from one sample period to the next sample period exceed a predetermined threshold value, the microprocessor outputs a signal, for example to operate an alarm system. Such a microprocessor typically employs a peripheral interface controller (PlC) running a dedicated software programme.

The comparator and/or microprocessor are preferably calibrated, either automatically or manually by the user, prior to operation of the system. In particular, the comparator and/or microprocessor are calibrated to recognise conditions of the tank being both full and empty. The system may be arranged to allow such calibration to be input manually by the user or for the processor to retrieve these data automatically.

In one arrangement of the system of the present invention, both an analogue comparator and a digital microprocessor may be employed to monitor the pressure of liquid within the line.

The processor may be pre-programmed with data corresponding to the normal operation of the heating system. More preferably, the processor is able to be calibrated, that is be operated in conjunction with the boiler over a period of normal operation, in order to allow the processor to gather the requisite data from the pressure sensor so as to be able to recognise the oil pressures in the line corresponding to a normal operation of the boiler and heating system. In addition, the processor may be able to be calibrated with the oil pressures in the line corresponding to the tank being full and empty of oil. In this way, the processor may be more closely tailored to a given heating system and provide a more accurate indication of the normal operation of the heating system and the occurrence of abnormal events, such as a leak or : * * theft. ** S * * * * SS

For use, the processor may be provided with two modes of operation.

In a first or calibration mode, the processor is operable to collect data from the pressure sensor during a period of normal operation of the heating system in general and the boiler in particular. In this mode, the processor is collecting data which allow it to identify the oil pressures to be expected in the line during normal operation of the heating system. The processor may be programmed to provide the user with an indication when the calibration has been completed and sufficient data collected. In a second, or active mode, the processor is receiving data from the pressure sensor. When in the active mode the processor is able to determine if an abnormal event has occurred, such as the theft of oil from the tank or a leak. The processor is preferably provided with suitable switches to allow the user to switch manually between the different operating modes of the processor. Alternatively, or in addition, the processor may be arranged to regularly update itself by automatically switching from the active mode to the calibration mode. In this way, the processor may remain properly calibrated over an extended period of time, for example accommodating changes in the oil pressure within the line as a result of the level of oil within the tank falling gradually with normal use. For ease of construction, installation and operation of the system, it is preferred that the processor is arranged to be calibrated manually by the user, for example upon initial installation and, optionally, recalibrated after a prescribed period of operation and/or when changes or modifications to the heating system are made. S 25

The processor may be any suitable processing means for carrying out the functions described hereinbefore and hereinafter. Such processing means are known and are commercially available. The processor may also contain a memory for storing data received from the pressure sensor. Again, suitable means for storing such data are known and commercially available.

The systems of the present invention further comprise an alarm system. The alarm system receives signals and is activated by the processor.

Communication between the processor and the alarm system may be by any suitable means, for example by means of a cable. Alternatively, the communication may be wireless. Suitable means for providing communication between the processor and the alarm system are known and are commercially available. The alarm system may comprise a display that is operable by the processor to provide a warning or indication to a user, for example an audible and/or a visual warning. Suitable displays are know in the art and are commercially available. Alternatively, the alarm system may form part of the security system of the building in which the heating system is installed. For example, the building may be provided with an alarm system for detecting and alerting the user of intruders and/or fire. The systems of the present invention may employ such an alarm system and use the appropriate means of such a system for alerting the user.

As a further alternative, or in addition thereto, the alarm system may comprise means for generating a message to alert the user, for example by means of sending a text message or making a call on a telephone system, for example to alert the user by way of their mobile telephone. Still further, as an alternative or in addition thereto, the alarm system may comprise means connecting the system to an internal or external network and able to generate a message, such as an email message, for sending to the user via the network. S 25

In addition, the systems may further comprise a display operable in response to signals generated by the processor, in particular a visual display, to provide a constant indication to a user of parameters relating to the heating system. For example, the processor may be arranged to operate the display to indicate normal operating conditions of the heating system and/or the amount of oil present in the tank. The display may be operable continuously by the processor to provide a continuous indication to the user. Alternatively, the display may be operated intermittently, for example at the request of the user.

In use, the systems of the present invention operate as follows: The pressure of oil within the line is monitored by the pressure sensor and signals corresponding to the pressure of oil are transmitted to the processor. To calibrate the processor, either upon initial installation of the system and/or as part of a regular system maintenance program, the heating system, in particular the boiler, is operated in a normal manner. The processor is calibrated as hereinbefore described, so as to be able to recognise those conditions of oil pressure within the line that correspond to normal operation of the heating system. When activated, the processor operates to receive signals from the pressure sensor corresponding to the oil pressure within the line. The processor compares the received signals with the profile of oil pressures expected during normal operation of the heating system. If the oil pressure detected by the pressure sensor is within the expected range of pressure values, no action is taken. Should the signal received by the processor from the pressure sensor indicate a pressure falling outside the values of pressure expected for normal operation, the processor activates the alarm system, to alert users to the abnormal conditions occurring.

In use, the system can be arranged to generate an alert or an alarm to ::::. a user in response to rapid changes in the amount of oil in the tank, occurring a result of the rapid removal of oil from the tank during a theft or as a result of a leak, such as a fracture of the line or a rupture of the oil tank itself. The system may be arranged to provide an alert or alarm to the user immediately in response to a rapid change in the amount of oil in the tank or upon an amount in excess of a predetermined volume of oil being lost. Further, the system may be arranged to generate an alert or an alarm when a valve in the line is closed, such as the valve adjacent the tank or a fire valve. Still further, the system may be arranged to provide an alert or an alarm when the line is partially or wholly blocked. Finally, the system may also provide the user with an alert or alarm when the amount of oil in the tank falls below a predetermined amount, such as when the oil in the tank falls below 5 or 10% of the capacity of the tank. Such an alarm is useful in reminding users to replenish the oil in the tank. The system may be arranged to have the alarm system and/or display, if present, provide a different indication of each of the aforementioned situations, allowing the user to distinguish between the different events.

The alarm system of the present invention may be a temporary corn ponent of the heating system. More preferably, the alarm system is provided as a permanent component of the heating system. The alarm system may be fitted together with the heating system as a new installation.

Alternatively, it is an advantage of the present invention that the alarm system may be fitted to a pre-existing heating system. Still further, the alarm system, either as a temporary or permanent component of the heating system, may be used to test the integrity of the oil supply to the boiler or the integrity of valves and/or other components fitted to the oil line, for example by an engineer to carry out a check for leaks in the line and/or the tank or other components.

While the system and method of the present invention have been developed in relation to providing security against leaks and theft in oil-fired heating systems, as described above in relation to the storage of oil and for use in a heating system, in particular a domestic heating system, the principles of the system and method of the present invention may be applied more generally, to any pipeline or similar conduit carrying a fluid, in particular a liquid.

Accordingly, in a further aspect, the present invention provides a monitoring system for monitoring the condition of a pipeline and components connected thereto, the system comprising: a pressure sensor for detecting the pressure of fluid within the pipeline system; and a comparator for receiving a signal from the pressure sensor and comparing the signal with a signal expected during normal operation of the pipeline system and, in the event the signal received from the pressure sensor falls outside the range of signals expected from normal operation of the pipeline system, generating an output signal.

The system of the present invention may used in conjunction with any pipeline or the like, carrying a fluid, in particular a liquid. In this respect, the term pipeline' is a reference to any pipe, line or conduit carrying a fluid. The system responds to changes in the pressure of fluid within the pipeline and monitors these changes by comparing them with an expected range of pressures corresponding to normal operation of the pipeline system. Should an event occur, such as a leak, giving rise to a pressure outside the range of normal operation, the system provides in indication of this, for example by activating an alarm. In this respect, it has been found that each pipeline system may be considered to have a pressure signature, comprising components arising from each apparatus or unit connected to the pipeline, such as a tank, vessel, or processing equipment. During normal operation of the pipeline system, the fluid within the pipeline exhibits a value falling within the pressure signature of normal operation. In the event of a leak, or the like, ::::. a pressure value outside the normal operating pressure signature occurs, which is detected by the pressure sensor and the comparator.

S

*.s.. Details of the system are as hereinbefore described in relation to the specific application of detecting leaks or theft from a heating oil installation.

Thus, the pressure sensor may be any suitable means for detecting the pressure within the pipeline. Such means are well known in the art and are commercially available. The pressure sensor is most preferably a pressure transducer mounted in the pipeline and responsive to changes in the pressure of fluid within the pipeline.

The system further comprises a comparator, for receiving the signals generated by the pressure sensor and comparing these with the signals expected during normal operation of the pipeline system. Should the signals received by the comparator fall outside the range of signals expected, indicating an abnormal operating condition, the comparator generates a signal, for example to activate and alarm. Details of the comparator are as hereinbefore described, with reference to the specific application of the system to a heating system.

The comparator may be arranged to generate an output only in the case of an abnormal operating condition, such as arising when a leak in the pipeline system occurs. Alternatively, the comparator may be arranged to provide a continuous output, indicating the general operating condition of the pipeline system, this output in turn being used to generate a display, such as a visual display, for an operator or user of the system.

In a still further aspect, the present invention provides a pipeline system comprising a monitoring system as hereinbefore described.

Embodiments of the present invention will now be described, byway of example only, having reference to the accompanying drawings, in which:

I

* I..., * * Figure 1 is a diagrammatical representation of a heating system according to a first embodiment of the present invention; and Figure 2 is a diagrammatical representation of a heating system according to a second embodiment of the present invention.

Referring to Figure 1, there is shown a heating system, generally indicated as 2, for a domestic building, such as a house, having a wall 4 dividing the interior of the building from the exterior. The heating system comprises a tank 6 for holding a fuel oil. The tank 6 is disposed outside the building. The heating system further comprises a boiler 8 having a burner 10 and disposed within the building. A line 12 extends from the tank 6 to the burner 10 of the boiler 8 through the wall 4 of the building, in conventional manner.

The heating system is provided with a valve 14 in the line 12 adjacent the tank 6, allowing the line and boiler to be isolated from the tank. A fire valve 16 is also provided in the line 12, connected in conventional manner to a fire sensor 18 within the building. When in operation, the detection of a fire by the sensor 18 causes the fire valve 16 to be closed, in turn preventing the flow of oil from the tank 6 to the boiler within the building.

An alarm system is installed within the building to monitor the oil in the line 12. The alarm system comprises a pressure transducer 20 mounted to detect the pressure of oil within the line 12. A typical pressure transducer for the system shown in Figure 1 has an operating pressure range of from 0 to 1 bar, generating an output signal of from 4 to 20 mA. The pressure transducer is connected by a cable 22 to a processing unit 24. As an alternative to the cable 22, the pressure transducer 20 may communicate with the processing unit 24 wirelessly. The processing unit 24 comprises a processor for receiving *ei signals from the pressure transducer 20. The processor is arranged to have stored therein data indicating the pressure of oil within the line 12 expected for normal operation of the heating system. The data may be preprogrammed and stored in a memory associated with the processor. Alternatively, the processor may be arranged to be calibrated through use of the heating system, so as to acquire a data set corresponding to normal operation. The processor is further arranged to generate an output, depending upon the result of a comparison of the signal received from the pressure transducer and the stored data. In a simple configuration, the processor outputs a signal to activate an alarm, in the event that the signal received from the pressure transducer indicates a pressure of oil within the line 12 falling outside the range of pressures corresponding to normal operation. Alternatively, the processor may be arranged to provide a continuous output, displaying the pressure of oil within the line to a user and activating an alarm, for example, in the case of an abnormal event.

In operation, the pressure of oil within the line 12 will fluctuate within a substantially constant set of parameters, depending upon the state of the heating system, that is with the boiler 8 starting up, operating normally, shutting down or being off or dormant. The set of parameters will vary slowly over extended periods of time, for example as the level of the oil within the tank 6 falls with use. However, an abnormal event, in particular a leak in the tank or the line 12, or a theft of a substantial amount of oil from the tank, will cause the pressure of oil within the line 12 to be outside the normal operating parameters. The processor receives signals from the pressure transducer 20 and identifies whether the signal corresponds to a pressure expected of normal operation or corresponds to a pressure falling outside that of normal operation, as a result of the abnormal event. In the latter case, the processor activates an alarm, alerting users to the abnormal event. In this way, leaks from the tank or line, or the rapid removal of oil from the tank as would occur during a theft, can be readily identified and appropriate action taken.

*..: 30 Turning to Figure 2, there is shown an alternative arrangement for the heating system 2. Components in the system of Figure 2 corresponding to those of the system of Figure 1 are identified using the same reference numerals. In the system of Figure 2, the tank 6 is located with its outlet below the level of the burner 10 of the boiler 8. The pressure transducer 20 is located in the line 12 outside the wall 4 of the building. The system operates in an identical manner to that of Figure 1, as described above.

The alarm system of the present invention has been described and shown in Figures 1 and 2 in conjunction with a domestic oil-fired heating system. It will be appreciated that the system may be applied in analogous manner to other systems employing a line for transporting a fluid, in particular a liquid. * .** * S * *5 * * 55 * I ***S *

* **S.0 * * * * *** S. * S ** I. * * S * . ** S * * S I **

Claims

CLAIMS1. An alarm system for an oil-fired heating system, the heating system comprising a tank for storing fuel oil, a boiler having a burner and a line extending between the tank and the boiler for supplying oil from the tank to the burner of the boiler, the alarm system comprising a pressure sensor for detecting the pressure of oil within the line; a processor for receiving signals from the pressure sensor and arranged to identify the normal pressure conditions of oil in the line during start-up, normal operation, shut-down and rest of the boiler; and an alarm operable in response to a signal received from the processor, in use the processor activating the alarm when a change in pressure of oil in the line is detected that does not correspond to normal operation of the heating system.

2. The system according to claim 1, wherein the pressure sensor is a pressure transducer.

3. The system according to either of claims 1 or 2, wherein the pressure sensor is disposed in the portion of the line adjacent the burner.

4. The system according to claim 3, wherein the pressure sensor is disposed immediately upstream of the burner.

* .* * * * 5, The system according to any preceding claim, wherein the pressure sensor is disposed between any valves in the line and the burner. * S*** * S

6. The system according to any preceding claim, wherein the pressure sensor is disposed within the building housing the heating system. * 30

7. The system according to any preceding claim, wherein the pressure sensor detects the absolute pressure of liquid in the line.

8. The system according to any of claims I to 6, wherein the pressure sensor is responsive to changes in the pressure of liquid within the line.

9. The system according to any preceding claim, wherein communication between the pressure sensor and the processor is by means of a cable or is wireless.

10. The system according to any preceding claim, wherein the processor comprises an analogue comparator.

11. The system according to any preceding claim, wherein the processor is able to be programmed with data corresponding to normal operation of the heating system.

12. The system according to any preceding claim, wherein the processor is arranged to receive and process data relating to normal operation of the heating system to generate a profile of normal operating pressures of the heating system, against which the signals received from the pressure sensor are compared. S... * * .

13. The system according to any preceding claim, operable in a first mode, in which the processor is calibrated through use of the heating system and a second mode, in which the system is operable to detect a loss of liquid from the line or the tank. * 55

14. The system according to any preceding claim, wherein the processor is * 30 able to be calibrated with pressures corresponding to the tank being full and empty of liquid.

15. The system according to any preceding claim, further comprising an alarm, operable by the processor.

16. The system according to claim 15, wherein the communication between the processor and the alarm is by means of a cable or is wireless.

17. The system according to either of claims 15 or 16, wherein the alarm is audible and/or visible.

18. The system according to any preceding claim, further comprising an alarm system operable to generate a message to alert a user and dispatch the message by means of a telephone system or computer network.

19. The system according to any preceding claim, further comprising a display operable by the processor to provide information as to the operating condition of the heating system.

20. The system according to any preceding claim, being a permanent component of the heating system.

21. A heating system, in particular a domestic heating system, comprising : a boiler having a burner arranged to burn fuel oil; a tank for holding fuel oil; a line connecting the tank to the burner of the boiler; a pressure sensor arranged to measure the pressure of oil in the line; a processor for receiving signals from the pressure sensor and arranged to identify the normal pressure conditions of oil in the line during start-up, normal operation, shut-down and rest of the boiler; and an alarm operable in response to a signal received from :.*:: the processor; in operation the processor activating the alarm when a change in the pressure of oil in the line is detected that does not correspond to normal operation of the heating system.

22. A method of operating a heating system, in particular a domestic heating system, the system comprising a boiler having a burner for burning fuel oil; a tank for holding fuel oil; and a line extending between the tank and the burner for supplying oil from the tank to the burner; the method comprising measuring the pressure of oil in the line; determining the pressure of oil in the line during normal operation of the boiler; identifying when the pressure of oil in the line falls outside the range of pressures corresponding to normal operation of the boiler and in such events activating an alarm.

23. A monitoring system for monitoring the condition of a pipeline and components connected thereto, the system comprising: a pressure sensor for detecting the pressure of fluid within the pipeline system; and a comparator for receiving a signal from the pressure sensor and comparing the signal with a signal expected during normal operation of the pipeline system and, in the event the signal received from the pressure sensor falls outside the range of signals expected from normal operation of the pipeline system, generating an output signal.

24. A pipeline system comprising a monitoring system according to claim 23. *.�S * . S

25. A monitoring system substantially as hereinbefore described, having *.** reference to either of Figures 1 or 2. * SS* * I

26. A heating system substantially as hereinbefore described, having reference to either of Figures 1 or 2.

* 30 27. A pipeline system substantially as hereinbefore described, having reference to either of Figures 1 or 2.

28. A method substantially as hereinbefore described, having reference to either of Figures 1 or 2. * * * ** I * III a * **e* * * *IIIS* .1 * S I. ** * * * * I II * * I S S *I Amendments to the claims have been filed as followsCLAIMS1. An alarm system for an oil-fired heating system, the heating system comprising a tank for storing fuel oil, a boiler having a burner and a line extending between the tank and the boiler for supplying oil from the tank to the burner of the boiler, the alarm system comprising a pressure sensor for detecting the pressure of oil within the line; a processor for receiving signals from the pressure sensor and arranged to identify the normal pressure conditions of oil in the line during start-up, normal operation, shut-down and rest of the boiler; and an alarm operable in response to a signal received from the processor, in use the processor activating the alarm when a change in pressure of oil in the line is detected that does not correspond to normal operation of the heating system.2. The system according to claim 1, wherein the pressure sensor is a pressure transducer.3. The system according to either of claims 1 or 2, wherein the pressure sensor is disposed in the portion of the line adjacent the burner.4. The system according to claim 3, wherein the pressure sensor is disposed immediately upstream of the burner.* .* * 5, The system according to any preceding claim, wherein the pressure sensor is disposed between any valves in the line and the burner. * S*** * S6. The system according to any preceding claim, wherein the pressure sensor is disposed within the building housing the heating system. * 307. The system according to any preceding claim, wherein the pressure sensor detects the absolute pressure of liquid in the line.8. The system according to any of claims I to 6, wherein the pressure sensor is responsive to changes in the pressure of liquid within the line.9. The system according to any preceding claim, wherein communication between the pressure sensor and the processor is by means of a cable or is wireless.10. The system according to any preceding claim, wherein the processor comprises an analogue comparator.11. The system according to any preceding claim, wherein the processor is able to be programmed with data corresponding to normal operation of the heating system.12. The system according to any preceding claim, wherein the processor is arranged to receive and process data relating to normal operation of the heating system to generate a profile of normal operating pressures of the heating system, against which the signals received from the pressure sensor are compared. S... * * .13. The system according to any preceding claim, operable in a first mode, in which the processor is calibrated through use of the heating system and a second mode, in which the system is operable to detect a loss of liquid from the line or the tank. * 5514. The system according to any preceding claim, wherein the processor is * 30 able to be calibrated with pressures corresponding to the tank being full and empty of liquid.15. The system according to any preceding claim, wherein the communication between the processor and the alarm is by means of a cable or is wireless.16. The system according to any preceding claim, wherein the alarm is audible and/or visible.17. The system according to any preceding claim, further comprising an alarm system operable to generate a message to alert a user and dispatch the message by means of a telephone system or computer network.18. The system according to any preceding claim, further comprising a display operable by the processor to provide information as to the operating condition of the heating system.19. The system according to any preceding claim, being a permanent component of the heating system.20. A heating system, in particular a domestic heating system, comprising a boiler having a burner arranged to burn fuel oil; a tank for holding fuel oil; a line connecting the tank to the burner of the boiler; a pressure sensor arranged to measure the pressure of oil in the line; a processor for receiving signals from the pressure sensor and arranged to identify the normal pressure conditions of oil in the line during start-up, normal operation, shut-down and * .S* rest of the boiler; and an alarm operable in response to a signal received from the processor; in operation the processor activating the alarm when a change *::: in the pressure of oil in the line is detected that does not correspond to normal * operation of the heating system. * 30 ** ** * * S * * S. S * S* S 5521. A method of operating a heating system, in particular a domestic heating system, the system comprising a boiler having a burner for burning fuel oil; a tank for holding fuel oil; and a line extending between the tank and the burner for supplying oil from the tank to the burner; the method comprising measuring the pressure of oil in the line; determining the pressure of oil in the line during normal operation of the boiler; identifying when the pressure of oil in the line falls outside the range of pressures corresponding to normal operation of the boiler and in such events activating an alarm.22. A monitoring system substantially as hereinbefore described, having reference to either of Figures 1 or 2.23. A heating system substantially as hereinbefore described, having reference to either of Figures 1 or 2.24. A pipeline system substantially as hereinbefore described, having reference to either of Figures 1 or 2.25. A method substantially as hereinbefore described, having reference to either of Figures 1 or 2. S... * S *1*S..... * * * *5 * * * * **SS S. *. S S * * I * S **