GB2462143A

GB2462143A - Heating system comprising wireless radiator control

Info

Publication number: GB2462143A
Application number: GB0813870A
Authority: GB
Inventors: Jeff Lowe
Original assignee: ETHOS SYSTEMS Ltd
Current assignee: ETHOS SYSTEMS Ltd
Priority date: 2008-07-30
Filing date: 2008-07-30
Publication date: 2010-02-03
Anticipated expiration: 2028-07-30
Also published as: GB2462143B; GB0813870D0; GB2462143B8

Abstract

A heating system comprises a plurality of radiators 3 and at least one radiator with a radiator control 4 capable of adjusting the heat output of the radiator. The radiator control has a radiator temperature sensor and a two way wireless communication link 2 with a central controller 1. The central controller stores a temperature against time profile for the radiator and provides control signals to the radiator control to enable it to adjust the heat output by the radiator dependent upon a radiator temperature signal provided by the radiator control. The radiator temperature signal takes account of the temperature sensor and whether the radiator is on or off. The radiator control may comprise a valve which may be adjusted by an electrical actuator having a power supply, such as a battery. Preferably, each radiator is individually identifiable by the central controller by using a locally unique handshake address. The central controller may also communicate 5 with a heat source, such as a water heating boiler 6, and communicate 7 with a flow driving means, such as a pump 8, to adjust the output of heat provided to the system.

Description

Heating System The present invention relates to heating systems and more particularly to heating systems known as central heating systems generally comprising water radiators or other radiant heaters (collectively known as "radiators") having a control for adjusting heat output.

Various forms of heating systems are known in which radiators are provided in particular rooms in order to provide heating within that room.

Typically the radiators are central heating radiators in which a supply of hot water is provided by a boiler in order to radiate heat although it is also known to provide night storage heaters which store heat in the form of ceramic blocks which radiate heat during the day.

A conventional central heating system as indicated will have a number of radiators arranged in different rooms with a boiler and normally a pump for circulation. The boiler and the pump are normally controlled through a central controller which simply switches on the boiler and operates the pump at certain times of the day. Traditionally, a thermostat is provided at a compromise location indicative of environmental temperature to adjust operation of the central heating system. A single thermostat is used to avoid complexity with respect to differential temperatures. In such circumstances the single thermostat acts essentially as an on off switch with regard to temperature acquisition for the entire building. Such an approach results in a central heating system which lacks sensitivity and flexibility to different occupation levels or other variables.

More recently within the context of providing a single central controller for on off operation regulated by a thermostat at a compromise position for whole building determination, it has been known to include thermostatic radiator valves. These thermostatic radiator valves will have a degree of local manual control to reduce the heat output by a radiator itself rather than depend upon the central compromise thermostat. Thermostatic valves achieve local control of the radiator without manual intervention with a simple twist flow regulator valve with early systems.

There is an increasing desire to utilise energy in a more efficient and economic way. Prior arrangements in which whole buildings are heated to a common temperature and in which other variables are not considered leads to inefficiency and wastage.

In accordance with aspects of the present invention there is provided a heating system comprising a plurality of radiators and at least one radiator with a radiator control capable of adjusting heat output of the radiator, the radiator control has a radiator temperature sensor and a two way wireless link with a central controller, the central controller stores a temperature against time profile for the radiator and provides control signals to the radiator control to enable it to adjust heat output by the radiator dependent upon a radiator temperature signal provided by the radiator control, the radiator temperature signal takes account of the temperature sensor and whether the radiator is on or off.

Generally, all radiators have a control. Typically, the control comprises a valve. Generally, each radiator is individually identifiable by the central controller by a locally unique handshake address for two way communication through a two way wireless link.

Generally, each radiator is within a room and the room includes a room temperature sensor also in communication with the central controller and/or the radiator control.

Possibly, the system includes a remote temperature sensor positioned remotely from the plurality of radiators and in communication with the central controller.

Generally, the central controller is in communication with a heat source to adjust the output of heat provided to the system for each radiator.

Generally the heat source is a boiler.

Typically, the temperature against time profile is fixed for the system.

Alternatively, the temperature against time profile is adjustable by a user dependent upon current requirements. Possibly, the adjustment of the temperature against time profile is learned and/or stored by the central controller for amendment of the temperature against time profile. Possibly, the temperature against time profile is adjustable dependent upon prior necessary radiator control signals over a fixed time period. Typically, the fixed time period is a month or a year in order to accommodate for seasonal or occupancy changes with respect to a building within which the heating system is provided.

Possibly, the central controller monitors and determines response by the control for each radiator. Generally, the central controller monitors response by a response signal from a radiator to a control signal. Further possibly the central controller determines and monitors responses from the room temperature sensor. Additionally possibly the central controller monitors and determines response by the control through a signal from the remote temperature sensor.

Possibly, the control for each radiator is in communication with a respective room temperature sensor and/or remote temperature sensor to adjust the control signals when provided or provide temporary control signals if the two way wireless link fails.

Generally, the radiator control for each radiator may relay signals to and from the central controller or other controls in other radiators.

Typically, each radiator control is adjusted by an electrical actuator having a power supply. Typically, the power supply is hard wired to the radiator control. Alternatively, the power supply at least in part is provided by a battery or other electrical power accumulator for temporary operation of the control.

Possibly, each radiator control stores at least a portion of its own temperature against time profile. Advantageously, each radiator control stores other portions of temperature against time profiles for other controls of other radiators within range of the wireless link.

Embodiments of aspects of the present invention wi'l now be described by way of example with reference to the accompanying drawing figure 1, which is a schematic illustration of a heating system in accordance with aspects of the present invention.

With regard to heating systems as indicated above improving overall efficiency is important but it will also be understood that the cost of installation must also be considered. In accordance with aspects of the present invention essentially two way wireless links are created between individual radiators to enable control and adjustment of heat output from those radiators in response to temperature requirements. The radiators are associated with a source of heat such as a boiler which also is generally controlled through a wireless link with a central controller. Each radiator is within its own fixed volume or room and in such circumstances individual and specifically tailored heating regimes can be provided. A central control in accordance with aspects of the present invention located either remotely from the radiators or associated with one or more of the radiators stores a temperature against time profile for each radiator. The temperature against time profile for each radiator is tailored to expected operational requirements such as occupancy, time of day, adjustment for season (winter, spring, summer, autumn) and day (weekday or weekend). By providing a specific temperature against time profile for each radiator as indicated, more accurate meeting of user demands are achieved with more effective utilisation of available energy.

In accordance with aspects of the present invention each radiator incorporates its own adjustor as a radiator control, off or on for heat output by the radiator as well as possibly room temperature. In such circumstances the temperature for the room can be determined through the temperature associated with the adjustor typically in the form of a valve. The radiator controller incorporating the adjustor is in two way wireless communication with the central controller and in such circumstances the central controller will co-ordinate the radiator controls in each radiator for a desired response by having a stored temperature against time profile for that radiator.

Generally, as indicated above a particular radiator is associated with a particular volume in the form of a room. In such circumstances each room could have a room thermostat at a displaced location relative to the radiator.

The room thermostat is either in two way or one way wireless communication with the central controller. In such circumstances the room thermostat may provide a room temperature signal to the central controller in order to determine response from the radiator and in particular the radiator control for that radiator. Thus, the room thermostat provides a secondary means for determining response by the radiator control for the radiator.

A remote thermostat may also be located at a displaced position in order to act with respect to temperature variations in two or more rooms and in such circumstances again will provide a remote temperature sensing signal with regard to the responsiveness of the radiator contro' for each radiator. It will also be understood that the remote thermostat may provide an environmental temperature level indicative of the temperature outside of a building incorporating the rooms and therefore radiators of aspects of the present invention.

The central controller as indicated will tend to be in at least single and possibly two way wireless communication with a heat source such as a boiler.

In such circumstances the central controller will initiate action by the boiler in order to provide heat to the radiators for appropriate output. The central controller may configure the boiler appropriately to provide a more tailored amount of heat energy to the respective radiators dependent upon programmed consolidation of the temperature against time profiles for all those radiators in operation.

In order to be operable it will be appreciated that each radiator and in particular its radiator control in accordance with aspects of the present invention must have a unique address to enable access by the central controller and appropriate download of control signals to the radiator control for that respective radiator in terms of the temperature against time profile.

Such an approach will also enable identification of radiator controls and therefore radiators which are not responding appropriately.

Figure 1 provides a schematic illustration of a heating system in accordance with aspects of the present invention. Thus, a central controller 1 is in two way wireless communication 2 with a number of radiators 3 or other radiant heater and in particular radiator controls 4 for each radiator 3.

Although only two radiators 3 are illustrated it will be appreciated in a normal system a greater number of radiators 3 will be provided with associated radiator controls 4. In accordance with aspects of the present invention each radiator control 4A, 4B through the two way communication link 2A, 2B respectively can be adjusted in order to pass through an appropriate temperature against time profile for the radiator 3. The temperature against time profile relates to the heat output of the respective radiators 3, 4 through that temperature against time profile.

The central controller 1 is also in at least one way and typically two way communication 5 with a heat source such as a water heater boiler 6. As well as possibly through communication 7 with a pump 8 or other means of driving or regulating heat energy flow 9 through a circuit 10 including the radiators 3, heat source 6 and pump 8. In such circumstances the central controller 1 can as indicated above adjust the configuration of the heat source/boiler 6 to match the requirements of the radiators 3 in terms of required heat output and can possibly also alter the pump speed for the pump 8 or other regulator to again more closely specify the required fluid flow rate for the current heat output demands through the radiators 3.

Generally each radiator 3 is located within a respective volume or room 11 and in such circumstances each particular radiator 3 has responsibility for the heating requirement within that room 11.

As described above generally each radiator control 4 will incorporate means for altering the heat output of the respective radiator 3 as well as a temperature sensor to determine actual responsiveness of the radiator 3 to control signals passed through the two way wireless link 2. Each room 11 will possibly incorporate a room thermostat 12 which is in a spaced location relative to the radiator 3 and in particular the radiator control 4. In such circumstances each room thermostat 12 may be in communication with the central controller I as well as the radiator controller 4 to provide a feedback response in terms of temperature regulation within the room 11. This may allow adjustment of the temperature against time profile delivered to the control signals to the radiator and in particular radiator control 4 for specific responsiveness in view of short term or long term factors. A short term factor may relate to a sunny day and therefore a higher temperature being established at the initial outset for the heat output by the radiator 3. It will be appreciated that inherently within a room 11 there is a heating history with regard to heating requirements. Knowledge of the base temperature within the room 11 in such circumstances may allow more controlled delivery of the temperature against time profile either individually or collectively with other radiators 3 within the system such that more efficient achievement of the temperature against time profiles for all radiators 3 can be achieved with the resources available in terms of the boiler 6, pump 8 and other factors. More long term factors may be that a particular radiator 3 in a particular room 11 which is located in a south facing aspect such that the room heats as a result of that south facing aspect and therefore dependent upon the length of the incidence of sunlight, seasons and other factors the original temperature against time profile for that radiator will require adaptation. This adaptation may be achieved through the responsiveness of the room thermostat and specific adjustments of a user/occupier requirements of the room 11 with a south facing aspect or otherwise.

It will be understood that each individual user and owner of a building may have their own specific personal requirements. In such circumstances although a heating system in accordance with aspects of the present invention may initially be delivered and installed with a set up or default temperature against time profile for each radiator 3 this may be adapted through usage or personal requirements. Adjustment can be achieved through a remote control type device 15 which connects with the central controller 1 or each individual radiator control 4 to alter the heating requirements within a room 11. Through the two way wireless link 2a in such circumstances the temperature against time profile for the radiator 3 can be adjusted such that heat energy is not wasted. In such circumstances the temperature against time profile for each radiator 3 can effectively be learned from a base default profile.

The heating system in accordance with aspects of the present is invention will typically be located within a building 13 and in such circumstances a remote thermostat 14 can be provided. This remote thermostat 14 could be located within an unheated area or volume such as a stairwell or storage space in order to determine for a particular zone or region of the building 13 background temperature. In such circumstances the collective effect of the heat output from each radiator 3 will create background heating in such areas of the building 13 to allow for acceptability. Thus when the building 13 is in a standby mode and all that is required is heating to avoid frost damage the central controller 1 may simply take the value from the remote thermostat 14 to ensure the building remains at a base level above freezing. It will also be appreciated that the remote sensor 14 or a series of such sensors 14 could be in two way communication with the controller 1 to provide an ambient temperature for the building 13 in terms of sun orientation to again enable adaptation and modification specifically of the temperature against time profile for each radiator dependent upon that orientation and so again improve efficiency with regard to heat usage.

In view of the above it will be appreciated that, providing particular temperature against time profiles for each radiator 3 allows an adaptation of those profiles as well as providing wireless links, typically two way, which significantly improves operability with regard to heating systems.

it will be understood the radiator controls 4, the central controller 1, the heat source 6 and the pump 8 are normally hard wired to avoid problems with battery life. In such circumstances problems with respect to checking battery condition are avoided. However, in order to provide backup should there be a power failure, each component 1, 4, 6, 8 may include a battery to allow sustained operation for a period of time. Furthermore, the radiator controls 4 may also include at least a default or portion of the temperature against time profile for each respective radiator to allow continued use provided the heat source 6 can provide heat for heat output by the radiator 3.

In such circumstances particularly if there is wireless communication and association between respective radiator controls 4 and room thermostats 12 then the heat source 6 can provide heat to the radiator 3 for maintenance of temperature in accordance with that default or partial profile.

With regard to specific operation of aspects of the present invention it will be understood that the radiator controls 4 typically incorporate a valve actuator which is electrically controlled and operated. In accordance with aspects of the present invention as indicated above each radiator 3 incorporates a respective control and therefore valve. The control monitors the room temperature and as indicated communicates through radiator temperature signals to the central controller 1 the current status of the radiator 3 in terms of room temperature and heat output.

The central controller 1 manages the heat system by providing a temperature against time profile for each radiator 3. This temperature against time profile defines the ideal operating conditions for that radiator 3 with reference to actual temperature responsiveness within a room 11 and therefore allows more idealised utilisation of available energy for energy efficiency.

The central controller 1 in addition to controlling the controls 4 for each radiator 3 will also interface and communicate with the heat source in the form of the boiler 6 through radio or wireless signals. In such circumstances the heating system is readily adaptable and can be further adapted by particularly user adjustment typically through a remote control device to set up and change settings with regard to the particular room 11 These changes may be directed towards a central controller to directly adapt the temperature against time profile or act within a room 11 to adjust the temperature within that room and therefore through the feedback via the two way wireless link to adaptation with the controller 1 where required.

In order to allow retrospective installation generally the radiator controls 4 in accordance with aspects of the present invention will be configured to allow ready replacement of an existing valve for the radiator 3. Nevertheless, each valve within the radiator control 4 will be sufficiently sophisticated to allow variation and in particular opening and closing via the wireless link 2.

As will be described later generally each radiator control 4 will also enable relaying of control signals and measurement signals in terms of temperature values from respective radiator controls 4, room thermostats 12 and remote thermostats 14 to and from each other as well as to the central controller 1.

In the above circumstances within a heating system in accordance with aspects of the present invention with a radiator control 4 for each radiator 3 it is important that each radiator 3 is individually addressable by the central controller 1 to enable the controller 1 to upload and download signals in terms of presenting the temperature against time profile to each individual radiator 3 and in particular its radiator control 4 as well as receiving temperature and other operating response signals from the radiator 3.

Each control 4 incorporates a temperature sensor to relay room temperature to the central controller 1 to enable that the controller 1 defines through control signals to the radiator control 4 necessary actions in terms of heat output in order to meet the temperature against time profile. To ensure operation each radiator controller 4 will respond with not only a temperature signal but also an indication as to the heat output of the radiator 3.

S In accordance with aspects of the present invention it is advantageous if a room thermostat is always provided which is displaced and sited away from the radiator control 4 at a convenient place in the room 11 to allow further monitoring of the temperature and confirm appropriate operation of the radiator control 4 in order to meet the temperature against time profile. By displacing the position of the room thermostat 12 it will be understood the room thermostat 12 effectively acts as an automatic feedback control for the heat system in terms of adaptation of a temperature against time profile as well as actual responsiveness of the control 4 to signals from the central controller 1. It will be understood as an alternative the room thermostat 12 may be replaced by individual occupants of the room having access to a response device. In such circumstances the occupant can give a signal that the room is acceptable to them in a "yes" or "no" scenario. In such circumstances if the central controller is currently proceeding along one temperature against time profile in order to achieve a desired temperature within the room 11 the responses from the occupier may be ignored as the system is already taking actions to achieve the occupier's desires.

Alternatively, if the central controller believes the room 11 should be at its desired temperature and in such circumstances is not in accordance with the response from either the room thermostat or the user's requirements then the controller can alter the temperature against time profile, overriding that profile or otherwise to produce greater heat output from the radiator 3 as required. In such circumstances if there is no response from the room thermostat 12 or a further negative indication directly by the user through a wireless remote control then the radiator 3 and in particular the control 4 is not responsive.

This may be an indication as to failure within the system which will require repair.

By utilisation of wireless communications in accordance with aspects of the present invention it will be appreciated that individual rooms 11 can be controlled rather than previously whole zones with problems with respect to lack of sophistication with regard to heating profiles.

Each radiator control 4 could incorporate a motorised or other electrically actuated valve to vary the heat output from the radiator 3.

However, more normally as described later a spring loaded plunger valve may be used for greater reliability. Where used such motorised or electrically actuated valves are operated with a 12V DC or low voltage supply. This supply will also enable appropriate wireless communications, 12V and low voltage supplies allow ease and flexibility with respect to installation. There will clearly be a requirement if batteries are not utilised to hard wire both the radiator controls 4 and the thermostats 12, 14 but such additional cost may be offset by savings with regard to energy usage. Nevertheless, more stand-alone plunger valves would be advantageous.

By ensuring that each room 11 is individually controlled in terms of its temperature against time profile it will be understood that greater and truer central heating is achieved by aspects of the present invention. Energy is more efficiently used as the heating system will only heat up rooms which are being used or occupied rather than globally all rooms within the building within which there is the potential for occupation or use. It will be understood that the central controller 1 may learn occupation and usage patterns with respect to the rooms 11 and therefore respectively alter and adjust the temperature against time profiles for each radiator 3 in use. By such an approach significant reductions in wasted heat energy can be avoided without overall reductions in heating temperature for each room which will result in inconvenience and loss of comfort to a user.

By utilisation of a central controller 1 with individual temperature against time profiles for each control and each radiator 3 it will be understood that more accurate responsiveness of the heating system is achieved.

Previously it was possible to manually adjust each valve upon entry and exit of the room but this was unrealistic and rarely performed in use. Aspects of the present invention allow particular temperature against time profiles to be specified for a heating system which can be adapted over time but nevertheless will ensure more efficient use of heat over a heating cycle for a building.

As a central controller 1 is utilised it will be understood that this controller could be addressable remotely through a telephone link or otherwise in order to stimulate the controller to provide a temperature against time profile if a user anticipates alternate timings. For example, the user may indicate to the central controller 1 that they will arrive home a few hours earlier and in such circumstances the central controller may advance the temperature against time profile to meet that requirement and therefore ensure that the rooms 11 are at an appropriate temperature achieved in the most efficient manner when the occupant arrives.

Generally, it will be appreciated that a control regime will be set by the central controller which defines through algorithms an appropriate system of control signals to the respective radiator controls 4 to achieve the temperature against time profiles for the radiators 3. In such circumstances the central controller 1 and associated radiator controls 4 will utilise software and conventional instruction steps for altering the valves with the radiator controls 4. In particular, the software and algorithms expressed in that software as indicated will enable anticipation and achievement of temperature against time profiles as desired for each room through the radiator 3 in the most efficient manner. As indicated generally it is not a question of switching on the radiator 3 in terms of heat output in order to immediately achieve a temperature level within the room 11. In order to achieve a desired temperature in the room 11 a multitude of approaches can be taken in which the radiator 3 rapidly heats the room 11 through a high level temperature differential and high temperature heat output but such an approach may be inefficient in terms of boiler 6 operation and heat losses through the circuit 10 and otherwise. Alternatively, and if possible within the temperature against time profile for the radiator the temperature in the room 11 may be gradually brought to a desired level in anticipation of occupier and user requirements.

Furthermore, more heat energy might be directed to radiators which are currently off with an immediate occupancy requirement in comparison with rooms which will no longer be occupied or have not been occupied for a period of time. In such circumstances the boiler 6 may be run at its most efficient rate and furthermore by appropriate processes it may be possible to recover heat from radiators which are still currently hot in rooms which are no longer occupied in order to transfer that heat energy through the circuit 10 to those radiators which have an immediate or current occupier requirement.

In such circumstances the controller 1 through its algorithm will allow calculation of optimal times for operation of the valves within the radiator controls 4 as indicated for maximum efficiency and accuracy with regard to heating within a heating system. Furthermore, as indicated the controller 1 may generally learn the individual heating characteristics for each room or zone of rooms through a combination of time of year, previous responsive data and forecast algorithms which may include weather forecast algorithms.

Thus, it may be possible to maximise the usage of local climate conditions in order to achieve the desired temperature within a room or zone of rooms with a minimal or reduced amount of energy input.

It will be understood that the control regimes and algorithms in accordance with aspects of the present invention may be adaptable over time.

Such adaptation may be through wireless or physical linkage to a personal computer, internet connection, mobile phone or hand held set to enable software updates and calibration of a heating system in accordance with aspects of the present invention such updating may be also through a telephone link remotely to adjust the user's requirements.

Generally, in order to achieve adequate and accurate operation of an arrangement in accordance with aspects of the present invention it is important that the components and in particular the sensors and controllers are adequately calibrated. Generally components such as valves utilised with respect to the radiators in accordance with aspects of the present invention will be factory set. However, within degrees of manufacturing tolerance and other factors there will be variations in the absolute response of these components within a system. In accordance with aspects of the present invention a calibration stage may be utilised in order to accurately and specifically calibrate the individual components of the heating system in order to meet the temperature against time profile desired. In such circumstances tolerance and manufacturing error stack up with respect to the relative components is avoided and a more accurate and responsive system achieved.

With any system which is automated it will be appreciated that faults can occur and in such circumstances it is desirable to build within the system spare capacity and mechanisms for determining such faults. For example, the valves of the radiator controls 4 may stick or fail. Actual responsiveness is important with respect to temperature within the rooms and convenience of operation is desirable. With regard to valve sticking within radiator controls 4 it will be understood that generally motorised valves may or could be utilised but alternatively and possibly with greater reliability a spring loaded plunger which is activated by a wax element warmed through an electrical heater may be used. In such circumstances there is avoidance of the motor and gearbox combination which may fail and the small electric heater operated by the radiator control 4 in order to cause the wax element displacement of the plunger will be more reliable.

In terms of room monitoring as indicated in accordance with aspects of the present invention generally the radiator control 4 will be augmented and combined with room temperature signals from a room thermostat 12 as well as possibly remote temperature signals from a remote thermostat. This will enable the controller 1 to determine surrounding temperature to a room 11 as well as temperature within the room and therefore adjust the heat output achieve the desired response. In such circumstances by providing a local room thermostat it will be understood that this thermostat may be adjusted by a user dependent on particular requirements as well as the temperature sensor within the radiator control 4. Thus, desired temperatures can be altered if required and this alteration utilised through the two way wireless communication link 2 to alter the temperature against time profile for that radiator.

By aspects of the present invention a fully automated system is provided which avoids the inconvenience of manually controlling the heating system.

A potential problem with regard to the heating system of aspects of the present invention is a reliability of wireless links. It will be understood that there is a concern with regard to radio signal reliability particularly when a whole system is dependent upon such wireless communication. Aspects of the present invention provide critically in areas such as communication between a central controller 1 and the radiator controls for a two way link.

Thus, the central controller 1 through an appropriate control signal command to the radiator control will adjust the output from the radiator. The radiator control will provide a response signal back in terms of the current heat output setting (on or off) for the control valve which will indicate to the central controller responsiveness. In addition to that through the temperature levels provided by the radiator control 4 as well as a room thermostat 12 responsiveness of the radiator control can be confirmed. Such an approach is relatively cheap and clearly provides a rapid indication that a control signal message has been received or not.

Generally, heating systems in accordance with aspects of the present invention will utilise standard available wireless communication systems such as IEEE 802.15.4 which operates at in the order of a frequency of 2.4GHz.

Such an approach will allow control signals to be not only acknowledged but to send a message to the valve of a radiator control appropriately in to send a message to the valve of a radiator control appropriately in accordance with aspects of the present invention. If a message should fail repeatedly in terms of the two way handshaking approach of control signal and confirmatory response then again this can be logged as a fault which requires diagnostic and repair action.

As indicated above generally a 12V or low voltage supply will be utilised for valve and radiator control 4 operation. Historically there may be problems with regard to wireless and radio communication signal strength in terms of range particularly where such signals must pass through walls and doors and steel building structures. By aspects of the present invention each radiator control 4 in respective radiators 3 as well as potentially thermostats 12, 14 can act as relay stations for control signals and temperature measurement and response signals from other controls associated with other radiators 3. In such circumstances the distance between the central controller 1 and the respective controls is less important provided each radiator and its associated radiator control is within a communication range or distance.

Thus, as indicated generally there will be communication control to radiator control, control to thermostat and central controller to radiator control or thermostat 12, 14 so passing control signals and other signals back and forth along a control chain.

Heating systems in accordance with aspects of the present invention include effectively a co-ordinator (central controller), a router (control or through path or remote control) and an end device (a radiator or valve) these elements operate as follows: Co-ordinator All networks must have one (and only one) Co-ordinator, irrespective of the network topology.

At the network level, the Co-ordinator is mainly needed at system initialisation. In some circumstances, the network will be able to operate the Co-ordinator provides a routing path to parts of the network (for instance, in a Star topology, where it is needed to relay messages). Similarly the Co-ordinator provides services at the Application layer and if these services are being used (for example, Co-ordinator binding), the Co-ordinator must be able to provide them at all times.

The tasks of the Co-ordinator at the network layer are: * Selects the frequency channel to be used by the network (usually the one with the least detected activity).

* Starts the network.

* Allows child nodes to connect to it (that is, to join the network).

The Co-ordinator can also provide message routing, security management and other services.

Router A network which uses Tree or Mesh topology requires the presence of at least one Router.

The main tasks of a Router are: * Relays messages from one node to another.

* Allows child nodes to connect to it.

Note that a Router cannot sleep.

End Device The main tasks of an End Device at the network level are sending and receiving messages. An End Device can often be battery-powered and, when not transmitting or receiving, can sleep in order to conserve power.

Note that End Devices cannot relay messages and cannot all nodes to connect to the network through them.

The heating system has a mesh topology which operates as follows Mesh Topology A Mesh topology consists of a Co-ordinator, and a set of Routers End Devices. The network structure is the same as for the Tree topolc However, the communication rules are more flexible in that Router not within range of each other can communicate directly. This gives rise to m efficient message propagation and means that alternative routes can be fot if a link fails or there is congestion.

In the Mesh topology, a "route discovery" feature is provided w allows the network to find the best available route for a message.

A network can have one of three topologies: * Star * Tree * Mesh These are described below.

Star Topology This is the simplest and most limited of the possible topologies A Star topology consists of a Co-ordinator and a set of End Devi Each End Device can communicate only with the Co-ordinator. Therefon send a message from one End Device to another, the message must be sent via the Co-ordinator, which relays the message to the destination.

A disadvantage of this topology is that there is no alternative route if the RF link fails between the Co-ordinator and the target device. In addition, the Co-ordinator can be a bottleneck and cause congestion.

It is possible to use nodes with Router functionality in a Star network in place of End Devices. However, in this case the Routers are not allowed to have child nodes attached and so their Routing capability is not used.

Tree Topology A Tree topology consists of a Co-ordinator, and a set of Routers and End Devices. The Co-ordinator is linked to a set of Routers and End Devices; its children. A Router may then be linked to more Routers and End Devices; its children. This can continue to a number of levels. This hierarchy can be visualised as a tree structure with the Co-ordinator at the top.

Note that: * The Co-ordinator and Routers can have children, and can therefore be parents * End Devices cannot have children, and therefore cannot be parents.

* Nodes with the same parent are called siblings.

* Nodes with the same grandparent are called cousins.

The communication rules in a tree topology are: * A child can only directly communicate with its parent (and with no other node).

* A parent can only directly communicate with its children and with its own parent.

In sending a message from one node to another, the message must travel from the source node up the tree to the nearest common ancestor and then down the tree to the destination node.

A disadvantage of this topology is that there is no alternative route if a necessary link fails.

Modifications and alterations to aspects of the present invention will be understood by a person skilled in the technology. In such circumstances it will be understood that rooms may be grouped to act as a zone to again adapt the respective temperature against time profi!e for each individual radiator and room dependent upon variables such as occupancy. Thus, in the morning and early evening it is to be expected that an occupancy sequence will comprise bedroom, bathroom, kitchen etc. Thus the heating system through the central controller may incorporate or adapt temperature against time profiles to accommodate such changes and anticipate occupancy.

Claims

Claims 1. A heating system comprising a plurality of radiators and at least one radiator with a radiator control capable of adjusting heat output of the radiator, the radiator control has a radiator temperature sensor and a two way wireless link with a central controller, the central controller stores a temperature against time profile for the radiator and provides control signals to the radiator control to enable it to adjust heat output by the radiator dependent upon a radiator temperature signal provided by the radiator control, the radiator temperature signal takes account of the temperature sensor and whether the radiator is on or off.
2. A system as claimed in claim 1 wherein all radiators have a control.
3. A system as claimed in claim 2 wherein the control comprises a valve. * * *
4. A system as claimed in any of claims 1, 2 or 3 wherein each radiator is I...individually identifiable by the central controller by a locally unique handshake address for two way communication through a two way wireless link.

..
5. A system as claimed in any preceding claim wherein each radiator is *..: within a room and the room includes a room temperature sensor also in communication with the central controller and/or the radiator control.
6. A system as claimed in any preceding claim wherein the system includes a remote temperature sensor positioned remotely from the plurality of radiators and in communication with the central controller.
7. A system as claimed in any preceding claim wherein the central controller is in communication with a heat source to adjust the output of heat provided to the system for each radiator.
8. A system as claimed in claim 7 wherein the heat source is a boiler.
9. A system as claimed in any preceding claim wherein the temperature against time profile is fixed for the system.
10. A system as claimed in any of claims 1 to 8 wherein the temperature against time profile is adjustable by a user dependent upon current requirements.
11. A system as claimed in claim 10 wherein the adjustment of the temperature against time profile is learned and/or stored by the central controller for amendment of the temperature against time profile.
12. A system as claimed in claim 10 wherein the temperature against time profile is adjustable dependent upon prior necessary radiator control signals over a fixed time period.
13. A system as claimed in claim 12 wherein the fixed time period is a month or a year in order to accommodate for seasonal or occupancy changes with respect to a building within which the heating system is .is provided.
14. A system as claimed in any preceding claim wherein the central controller monitors and determines response by the control for each : radiator. * *,
15. A system as claimed in any preceding claim wherein the central controller monitors response by a response signal from a radiator to a control signal.
16. A system as claimed in any preceding claim wherein the central controller determines and monitors responses from the room temperature sensor.
17. A system as claimed in any preceding claim wherein the central controller monitors and determines response by the control through a signal from the remote temperature sensor.
18. A system as claimed in any preceding claim wherein the control for each radiator is in communication with a respective room temperature sensor and/or remote temperature sensor to adjust the control signals when provided or provide temporary control signals if the two way wireless link fails.
19. A system as claimed in any preceding claim wherein the radiator control for each radiator may relay signals to and from the central controller or other controls in other radiators.
20. A system as claimed in any preceding claim wherein each radiator control is adjusted by an electrical actuator having a power supply.
21. A system as claimed in claim 20 wherein the power supply is hard wired to the radiator control. * .e. * *
22. A system as claimed in claim 20 or claim 21 wherein the power supply at least in part is provided by a battery or other electrical power * 5 accumulator for temporary operation of the control.
23. A system as claimed in any preceding claim wherein each radiator * control stores at least a portion of its own temperature against time *:*. profile.
24. A system as claimed in any preceding claim wherein each radiator control stores other portions of temperature against time profiles for other controls of other radiators within range of the wireless link.
25. A heating system substantially as hereinbefore described with reference to the accompanying drawings.