GB2455886A - Thermostatic radiator valve - Google Patents

Abstract

A thermostatic radiator valve head unit adapted to operate a control valve 58 on a radiator comprises a thermostat device 52, a control knob 62, and engagement means 57 adapted to form a mechanical communication between the thermostat device 52 and the control valve 58 on the radiator. The unit further comprises a heating means 70 arranged to heat the thermostat device 52 and, when so heated, close the control valve 58 on the radiator independently of the ambient temperature.

Description

Control System

Field of the invention

This invention relates to a heating control system incorporating thermostatic radiator valves. It is particularly applicable1 but in no way limited1 to a heating control system whereby a number of locations, such as radiators, in a building can be independently controlled over a period of time from a central control unit, for example the control of individual radiators within a domestic central heating system.

Background to the Invention

There has recently been a new awareness of the need to reduce energy consumption in buildings and large Increases in fuel costs have spurred the need for a more efficient use of space heating.

In most practical situations, even with great determination on the householder's part, it is difficult to effectively control individual heating zones to the optimum and desired levels.

Most installations in common use today include a timer which can control hot water and heating but rarely in separate zones. Even if there are separate controls for heating and hot water, the heating is usually a single zone such that heating to the whole dwelling is either on or off. It is apparent that in many dwellings much heat is wasted by heating unoccupied or briefly occupied areas whilst in other cases rooms are left unheated at times when it would be better to heat them. There is a school of thought that a dwelling should be well Insulated and the whole kept to a constant temperature.

Whilst this argument may be valid for some small newly built units, for larger or less modem houses, a more sophisticated control system will provide a much greater degree of comfort at a greatly reduced cost.

It is an object of the present invention to provide a heating control system incorporating a novel type of thermostatic radiator valve particularly suitable for use with domestic central heating systems and which overcomes or at Least mitigates one of more of the problems noted above.

The present invention aims to overcome these problems by providing a control system whereby the heat supply to a number of locations in a building can be independently controlled over a period of time from a central control unit. Also it is suggested that the capital cost of providing such a heating control system would be quite modest and quite likely repay the investment in 12 months due to the savings in reduced waste energy.

The purpose of the invention is to provide a means whereby users of a building or buildings can easily and flexibly control the environment of specific different areas simultaneously via a time controller which can change the temperature, humidity, ventilation etc over any chosen time periods which can be individually selected for each area to be controlled.

The areas to be controlled can be any number dependent on the design of the control unit.

Summary of the Invention

According to a first aspect of the present invention there is provided a thermostatic radiator valve head unit adapted to operate a control valve on a radiator, said thermostatic radiator valve head unit comprising: (i) a thermostat device; (ii) a control knob; (ill) engagement means adapted to form a mechanical communication between the thermostat device and the control valve on the radiator; characterized in that the unit further comprises a heating means arranged to heat the thermostat device and, when so heated, close the control valve on the radiator independently of the ambient temperature.

By heating the thermostatic device to just above its normally fully extended or "fully closedu temperature, the flow of hot water into the radiator is interrupted. Because only a small amount of local heating is required this can be achieved very efficiently.

Preferably, the heating means comprises an electrical heating element. By providing an electrical heating element in or around the thermostat device this provides a particularly cost effective and energy efficient way of achieving the desired objective set out above.

Preferably, said electrical heating element comprises electrical windings. Helical windlngs are preferred.

Preferably, said electrical windings are located around the thermostat device.

In an alternative preferred embodiment, said electrical windings are located within the thermostat device.

Preferably, the unit further comprises control means adapted to control the power supply to the heating means. This control means can both regulate the current to any heating means or heating element to control the temperature to which the thermostat device is heated and can also control when heating is and is not provided.

Preferably, said control means incorporates a signal receiving means adapted to receive a signal from a controller. By providing a central controller, multiple zones can be controlled. A zone may be an individual radiator or groups of radiators.

Preferably, the unit further comprises an electrical power source. The power source may be internal to the unit, such as one or more batteries, or may be external to the unit such as from a mains power supply in the vicinity of the radiator.

According to a second embodiment of the present invention, there is provided a control system comprising: (i) a plurality of thermostatic radiator valve head units as claimed and described herein; (ii) a multi-zone controller, and (iii) signal means adapted to convey a signal from the controller to the thermostatic radiator valve head units.

In the context of this invention and description, the term "plurality" has the meaning "one or more".

Preferably, the signal means is a mains communication device. In this way no additional wiring is needed between the multi-zone controller and the thermostatic units.

By plugging the multi*zone controller into the mains, and by connecting each of the thermostatic units to the mains, the mains wiring can be used to convey the necessary signals from the controller to the individual units.

Preferably, the control device incorporates a display adapted to display the status of each zone. An easy to read display is a most desirable feature, such that the operator or householder can tell at a glance which radiators have been rendered closed down.

Brief Descriotiop of the Drawings The invention will be further described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a diagram showing how thermostatic radiator valve head units and a control system incorporating such units can be integrated into a multi-zone heating system; Figure 2 illustrates a thermostatic radiator valve head unit according to a first embodiment of the invention; Figure 3 is the front view of a controller; Figure 4 is a schematic diagram of the controller of Figure 3; Figures 5 and 6 show diagrammatically the display on a typical control module; Figures 7, 8 and 9 show a thermostatic radiator valve head unit with the control knob set to close the valve, with the control knob open but the sensor not heated, and the control knob open but the sensor heated, respectively.

Descrl�tion of the Preferred Embodiments The present invention will now be described by way of example only. These examples represent the best ways known to the Applicant of putting the invention into practice, but they are not the only ways this can be done.

This system provides for individual control of any number of zones in a building. A medium sized house might typically need six or eight individually controlled areas or zones. The terms "zone" and "area" are used interchangeably.

There are three main considerations: a) The central control unit.

b) The control at the remote area/zone to be heated, being a thermostatic radiator valve unit.

c) The communication between a) and b).

Central to the control system of the present invention is a novel type of thermostatic radiator valve head unit. Referring to Figure 2, one such unit 50 is illustrated connected to a radiator valve unit 51. The unit 50 comprises a thermostat or heat sensor 52.

Such thermostats are typically of the wax-filled kind. As the temperature around the unit increase a thermostat pin or plunger 60 projects increasingly far out of the heat sensor. Conversely, as the temperature around the unit falls, the plunger retracts into the heat sensor. The plunger is generally in contact with a plunger 53, which is spring loaded by way of an upper helical compression spring 54. This spring is located within a hollow piston 55. This piston is free to move up and down In a housing 56, as dictated by the position of the plunger 60. The compression spring 54 is generally strong enough that the plunger 53 is always held against the inner upper surface of the piston 55.

However, it will be appreciated that, in the event the control knob is in its closed position, i.e., fully wound down, and the heat sensor is very warm and hence plunger 260 extended to its maximum, then the compression spring 54 may be depressed to accommodate any excess movement of the plunger 60.

The lower external surface of the piston 57 engages with the plunger or needle of a conventional radiator valve 51. In Figure 2 this valve is shown in its closed position, with valve plunger 58, and associated 0-ring 59, in sealing contact with the valve seat 61. A control knob 62, in coarse screw thread engagement with the unit bOdy 63.

allows for adjustment as to the temperature at which hot water is allowed into the radiator, assuming that hot water and heating are asked for.

The radiator valve plunger or needle 58 is biased upwardly by a second or lower compression spring 64.

Thus far has been described a conventional type of thermostatic radiator valve heat unit. However, in this unit an additional component has been incorporated. This is a small heating element 70. This heating means, once activated, heats the wax in the heat sensor to a temperature above which the radiator valve would be fully closed.

Typically this temperature would be greater than 26°C and typically in the range 27- 37°C, more preferably 28-35°C. Connecting wires 71, 72 connect the ends of the heating element to a power input socket 73 on the outside of the unit. These connecting wires pass through the body of the unit. To prevent the heat sensor rotating with the control knob 62 a pin 73 anchors the heat sensor preventing annular rotation.

Alternatively electrically conducting guide rods not only provide electrical connections for the heating element but also maintain axial alignment of the heat sensor 52 and the plunger 55.

The piston plunger 55 can also be prevented from turning or rotational axial movement by means of a lug on the piston located within a groove (see Figures 7, 8 and 9).

In this example the heating element comprises a nickel/chromium heating element in a PTFE sleeve, tightly fitting around the outside of the heat sensor. It is equally possible that this heating element is located within the heat sensor itself. The external arrangement provides for an easy after-market modification of an existing thermostatic radiator valve, or for a production modification. The internal heating element arrangement simply requires a different heat sensor. In either case the change is simple to carry out The heating elements may be covered in insulation but if this extends over much of the outer surface of the heat sensor, it will decrease its speed of response.

This invention therefore provides methods of controlling the operation of a thermostatic radiator valve in order to override the condition maintained by either the setting of the control knob or the temperature of the air around the valve. It operates by artificially increasing the temperature of the sensing device so as to close the control valve as required, thus preventing the radiator operating.

The purpose of this device is to facilitate remotely controlling the heating in the room.

either from another part of the room or from any other location. This being from a control switch or a timer control unit, with a means of transmitting the controlling signal to the device (see below for options).

At the local control valve the heat may be applied by any suitable heating means. This could be by an external source of energy applied from outside the valve sent from a radiating source of any frequency of electromagnetic radiation or sonic or any other type of energy or by an internal electric heating element, mounted in the proximity of the sensing device connected by wiring from the exterior. This can be an element or coil made from a wire or wires of appropriate electrical resistance determined by the control voltage applied and the amount of heat required to operate the sensor. The heating device may also consist of any other electrical component capable of producing controlled heat such as a semiconductor or electric lamp.

A typical embodiment of the invention would be almost any type of normal thermostatic radiator valve operated by a wax thermostat sensor, modified with a coiled element of two or three turns of nickel-chrome wire, Insulated and wrapped around the body of the wax sensor. In practice it is convenient to control the element with perhaps a five volt supply passing around 0.3 amps in an element with a resistance of 18 ohms, producing approximately 1.5 watts of heat, these figures being given by way of example only. A relatively low voltage being desirable for safety and the need for a reasonably robust and reliable element.

It will also be appreciated the heat sensor need not be of the wax filled type. This invention will work with any type of sensor, since applying an extra external heat source to any sensor will cause it to operate to its maximum extent.

The interior of the valve head is designed to allow the wire connections from the element to be routed safely via the stationary part of the valve body to the controlling supply voltage from the exterior of the valve. This could also incorporate a plug and socket or other connector for convenience, It is also proposed that the control circuit may include a device to at times reduce the electrical current in the element to the minimum required to maintain the valve in the closed position.

It is proposed that the controlling supply is either wired directly from a remote controlling unit, or connected to a locally powered unit in the room in which the radiator is located, and which is controlled by a signal sent by radio or wireless means or by a digital signal conveyed by means of the house power or other cables. The remote signal controlling the locally powered unit in order to produce the electric output to the device when the radiator is required to turn off and switching off the electric output to the device when the heating is needed.

It is important that a central master control unit should provide easy access, control and indication of functions. This should be easy to interpret by persons of varying abilities and degrees of familiarity with the system. Many electronic time clocks in this situation have little control apart from basic functions, are difficult to interpret, particularly for someone unfamiliar with them and are not easy to reprogram. Although this invention is intended to cover any mechanical or electronic means of achieving its purpose, it is felt that a well designed electric motor controlled unit would provide one user-friendly solution, as well as providing a unit of well tried, low cost mechanical reliability, having a long life.

The unit needs a reasonably sized multi-zone timer, displaying each zone, with on and off times easily visible, easy access to a means of changing time programmes and a means of setting and re-setting the clock.

Well designed switches to control each zone individually, where each zone can be: a) left on preset timer settings, b) switched ON to over-ride the timer and c) switched OFF to over-ride the timer.

There would ideally be indicator lights to show the operating state of all zones.

Additionally a late on" function should be provided to over-ride the ON times to a later time of day. Also, a switch position can be provided designed to take the output from a phone switch or other remote control device, allowing remote control of the system from a distant location. Such phone-in technology is well known to those skilled in the art.

In one embodiment the unit is manufactured with its main operating device being a rotating cylinder with adjustable projections on its inner or outer surface which operate switches. However one preferred embodiment, shown in Figure 3, comprises a rotating disc with concentric rings or bands 121 to 128 desIgnated to each switching zone or function. This disc rotates at one revolution per 24 hours with each ring divided into sections of time division (typically 15 or 30 mm). At each time division a movable or adjustable lever or peg is provided for setting ON and OFF times. These project through to the rear of the disc to operate electric switches and thence the remote devices.

Referring again to Figure 3 which represents one example of a multi-zone controller, it can be seen that there are 8 different zones which are controlled by the main control unit 110. Each zone has a control switch, 111 to 118, whereby that circuit and thus zone can be turned on, off or timed. When the control switch for a particular zone is set to timed, then the time at which the heating will turn on and off in that particular zone is controlled by the timing wheel. In this particular embodiment the pegs are in the places indicated by an x and when a peg is located in a hole, the system will turn the heat on in that zone at that time.

Additionally with the system an electrical output is provided at the appropriate times to control the boiler and the water-circulating pump. In order to facilitate this, the switches operated by the moving disc need to be double pole. Alternatively each zone switch output can be fed via a silicon diode to a relay, or solid state-switching device, to operate the boiler. Secondly if the motorised valves are of the five-wire type -that is with the control motor remaining un-energised during operation, the zone switch needs to be double throw or changeover. This is just one way in which the circuitry may be constructed. However, a person skilled in the art will appreciate that there are many ways in which this can be achieved. A suitable design will be devised by a qualified person using the most up-to-date, practical and reliable components available at that time. Whilst the design is an important factor, it is the functionality which the Applicant is seeking to protect.

A key element however is that a single multi-zone controller controls a multiplicity of zones, and generally more than three zones as found in most prior art controllers.

A schematic diagram of a control unit is shown in Figure 4.

in the control of a heating system with water filled radiators, there are two approaches.

One is to have a number of solenoid or motorised water flow valves near the boiler or source of heat which feed each room by separate pipework. The other is to have the appropriate valves in each room on or near each radiator. These can be connected by electric wiring to the central control unit. This latter type of arrangement is easier to install in both pre-existing systems and in a new building. Alternatively the system can be radio controlled with a coded transmitter in the main control unit sending a signal to a radio receiver attached to and controlling each remote valve. Such remote control systems are known per se and are used, for example, in remote control conservatory blinds. In any event, remote control technology to control multiple zones is well known to the person skilled in the art.

Figure 1 illustrates one possible arrangement in which four radiators are shown. Each radiator 31 to 34 has a valve-operating device 41 to 44 to control when hot water may or may not enter that particular radiator. In this example, each valve-operating device is wired back to the control urnt 35. Alternative arrangements which do not necessitate hard wiring between the control unit and theleach valve-operating device are described below. One example of a valve-operating device is the novel type of thermostatic radiator valve head unit described above.

it is envisaged that there are a number of options for the form and positioning for the valve-operating devices. This valve-operating device could replace the thermostatic head of a conventional thermostatically controlled radiator valve. Alternatively the valve-operating device can be incorporated as an integral part of a thermostatically controlled radiator valve or as an integral part of the thermostatic head of such a valve.

This would result in a valve of neater and more aesthetically pleasing design.

It is thus envisaged that one option would be to Install the valve controller with Its own thermostat onto a standard thermostatic radiator valve, thus providing the possibility of installing the system without any necessity to drain down the system.

Although time switches which can turn an item on or off over a 24 hour period are known, it is not known to provide a controller that can turn on and off five or more circuits In this way with the adjustability described above.

Included in the invention are means of sending the control information to the area to be controlled or to the device controlling the environment in the controlled area.

Also included are practical means of using the control information to operate the control devices.

It will be appreciated that the heart of the control system invention, in addition to the thermostatic radiator valve head unit, is the control unit to be operated by the user. This could be:-A) A mechanical timer controlled by an electric motor.

B) An electronic unit using semiconductor devices.

It is important that the control unit has a display unit which provides readily and easily interpretable information about all the areas under control coupled with means to vary or switch the various functions and time controlled periods.

The control information from the timer unit to the local operating device is transmitted by any practical means but may include:-A) Direct electric wiring.

B) Electromagnetic wave wireless signals.

C) Digital or analogue encoded modulated signals sent via the power supply or other pre-existing cables.

D) Ultra sonic, infrared or other signals.

At the receiving end of the transmitted information a device must be used to control and operate the unit or device controlling the environment.

The transmitted information can also be used to operate a local information display unit in the controlled area.

At the present time, against the background of rising fuel costs and pressure to reduce the carbon footprints of buildings, it is thought that the most easily installed embodiment of this invention would be an example to operate in a modest domestic environment to provide both a saving by reducing unnecessary heating in unoccupied areas and also by providing heating in other areas exactly when and where it is required so as to produce a more comfortable environment at lower cost.

As an example a timer unit is provided to produce controlling output signals to six or eight separate zones The unit comprises an electronic device, utilising programmable integrated circuits containing a master device, also controlling a display showing the times set for each of the zones to be controlled. An example of such a display unit is illustrated in Figures 5 and 6. These illustrate area control switches 161 to 168. Each switch has three positions, AUTO', in which the zone goes on or off according to the programmed times, CONSTANT ON' in which heat may always reach the radiator if called for, and OFF' in which heat is permanently cut off from the radiator.

Area labels 171 to 178 are provided which may be handwritten or part of the electronic display. The present time is indicated by an indicator bar 179. Interconnecting switching will allow any time slot selected to be altered in length or position in real time.

Switching will also allow the on' periods to be individually overridden or to be substituted with constant on' or constant off' states for individual zones.

An LCD or LED display 180 shows the status of each zone or area throughout the entire 24-hour period. The various possible combinations are shown in Figure 6 as follows:- 181 -selector switch set to CONSTANT ON'.

182 -selector switch set to OFF'.

183 -No AUTO settings for that zone.

184 -Selector switch set to normal AUTO' run position.

The differently hatched areas of each bar show when the valve-operating device is open or closed. A reset/select button enables each zone to selected in turn in order to set the ON' and OFF' times for each zone using ON' OFF' switches 86.

The electronic device will thus provide at the appropriate times a switch on' signal for the heating boiler or other heat source.

It will also provide a switch on' and a switch off signal at the appropriate times to a mechanical device controlling the heat output of, for example, a hot water radiator.

The electronic device preferably includes means to encrypt the signals into a digital code to be sent via the household power supply cables to any location required in the building. The technology to transmit signals along a 11 Ov/240v cable in a domestic wiring system is well known. Examples such as HOMEPLUGS.CO.UK are available from Flashbyte.Net Limited, 7 Church Road, Shoeburyness, Essex SS3 9ET, Company Number 03877045.

The controlled display device can be configured in a number of different ways using one of the several types of electronic display devices currently available. A ready manufactured liquid crystal display unit could display current time plus a clear graphic display of the on and off time slots for each area selected in turn.

A larger light emitting diode display or liquid crystal display could display aD timed zones and their current active state simultaneously. The display device can be optionally constantly displaying or activated to display only when it is needed to check the timing or to make an adjustment.

As an example the electronically controlled device or valve-operating device at the local area to be controlled is that shown in Figure 2 and as described above.

It will therefore be appreciated that a special valve can be manufactured which replaces an existing conventional radiator valve entirely.

The valve is controlled via a low voltage signal supplied from a receiver unit installed or plugged into a suitable nearby mains supply.

The receiver unit consists of a low voltage power supply coupled to a decoder to interpret the mains born digital signals sent from the main control unit.

A fUrther possible variation of the radiator controller is to contain an electrical switching thermostat in the receiver unit to be plugged Into the power socket and feed via electrical wiring the controlling electrical signal to a unit containing an electro-mechanical operating device to open or close the valve. This unit will simply replace the normal thermostat part of the thermostatic radiator valve.

In any event, it will be appreciated that an extra level of control is provided, over and above the normal on/off control of the heating system and the normal thermostatic control of the radiator valve. This extra level of control is provided by a multi-zone, radiator-by-radiator controller and a special valve-operating device on one of the radiator valves.

In practice the power supply, electronic control boards and associated display device will be contained in one self-contained unit which can be placed in any convenient place in the building. As the mains power supply into the unit and the output control signals both travel via the connecting cable to a power socket, the only installation required Is to plug the unit into a wall socket. In its simplest form, the controller for these radiator valves may be a stand alone unit, installed in addition to the boiler control unit, as an after-market item. Alternatively, it could be incorporated into a new multi-function boiler control unit.

Figures 7, 8 and 9 illustrate a thermostatic radiator valve head unit in various phases of operation. Figure 7 illustrates one embodiment where the heat setting knob 262 is screwed in to its fullest extent. This represents a situation where the radiator valve is permanently closed. Figure 8 shows the same unit where the control knob 262 is open, no artificial heat has been applied to the heat sensor, and the radiator valve Is open, calling for heating.

In Figure 9, the heat setting knob is also open but in this example the heat sensor is being heated. This causes the radiator valve to close, and it will remain closed until heat is removed from the heat sensor.

The scope of this invention also covers the possibility of providing two or more different preset levels of temperature at various times rather than simple ON or OFF periods.

This would need a more complex timer unit with extra timed channels -possibly more suited to installations in other than domestic situations.

Claims (13)

1. Claims: 1. A thermostatic radiator valve head unit adapted to operate a control valve on a radiator, said thermostatic radiator valve head unit comprising: (i) a thermostat device; (ii) a control knob; (iii) engagement means adapted to form a mechanical communication between the thermostat device and the control valve on the radiator; characterized in that the unit further comprises a heating means arranged to heat the thermostat device and, when so heated, close the control valve on the radiator independently of the ambient temperature.
2. 2. A thermostatic radiator valve head unit as claimed in Claim 1, wherein the heating means comprises an electrical heating element.
3. 3. A thermostatic radiator valve head unit as claimed in Claim 2, wherein said electrical heating element comprises electrical windings.
4. 4. A thermostatic radiator valve head unit as claimed in Claim 3, wherein said *:*::* electrical windings are located around the thermostat device. p..
5. 5. A thermostatic radiator valve head unit as claimed in Claim 3, wherein said electrical wiridings are located within the thermostat device.

   S.....

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6. 6. A thermostatic radiator valve head unit as claimed in any preceding claim, *:::: wherein the unit further comprises control means adapted to control the power supply to the heating means.
7. 7. A thermostatic radiator valve head unit as daimed in claim 6, wherein said control means incorporates a signal receiving means adapted to receive a signal from a Controller.
8. 8. A thermostatic radiator valve head unit as claimed in any of Claims 2 to 7 inclusive, wherein the unit further comprises an electrical power source.
9. 9. A thermostatic radiator valve head unit substantially as herein described with reference to and as illustrated in the accompanying drawings.
10. 10. A control system comprising: (i) a plurality of thermostatic radiator valve head units as claimed in any of Claims I to 9 inclusive; (ii) a multi-zone controller; (iii) signal means adapted to convey a signal from the controller to the thermostatic radiator valve head units.
11. 11. A control system as claimed in Claim 10, wherein the signal means is a mains communication device.
12. 12. A control system as claimed in Claim 10 or Claim 11, wherein the control device incorporates a display adapted to display the status of each zone.
13. 13. A control system substantially as herein described with reference to and as illustrated in any combination of the accompanying drawings. * * ** * * * * * **

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