WO2023225690A1

WO2023225690A1 - Thermal adapter

Info

Publication number: WO2023225690A1
Application number: PCT/ZA2023/050016
Authority: WO
Inventors: Nicholas Lee ROCHE; Michael James SOPER
Original assignee: Symion Automation And Energy (Pty) Ltd
Priority date: 2022-05-20
Filing date: 2023-03-23
Publication date: 2023-11-23
Also published as: ZA202303769B

Abstract

There is disclosed a thermal adapter (10) comprising a base (12) and an elongate strip (14) of thermally conductive material extending from the base. The base is configured to be fitted at an opening (16) of a thermostat pocket (18) of a water heater (20) with the elongate strip extending into the thermostat pocket. The base (12) provides an attachment point (22) for a thermal sensor (24) connected to the elongate strip. The elongate strip and the base are shaped to permit a thermostat rod (26) to fit into the thermostat pocket alongside the elongate strip. The present disclosure extends to a method (100) of manufacturing the thermal adapter, and a water heater (20) having the thermal adapter installed and connected to an external circuit (58).

Description

THERMAL ADAPTER

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from South African provisional patent application number 2022/05553 filed on 20 May 2022, which is incorporated by reference herein.

FIELD OF THE INVENTION

This invention relates to water heaters. More particularly, but not exclusively, this invention relates to a temperature sensor for a water heater.

BACKGROUND TO THE INVENTION

Water heating is traditionally performed by water heating vessels known as water heaters. Water heating is often done electrically, but some types of water heaters are gas powered.

In water heating systems, a thermostat is generally used to regulate the water temperature in the water heater. The thermostat is fitted to a thermostat pocket or aperture in the water heating vessel, and the thermostat senses the temperature of the water. The thermostat is usually adjusted to a set temperature, and operable to switch off a heating element of the water heater once the water has been heated to the set temperature.

Water heater control systems require temperature readings of water temperature to be obtained. Since existing thermostats may be thermo-mechanical devices, to be readable by the control system the thermostat may be replaced with a temperature sensor, or the water heater otherwise modified to include the temperature sensor. This carries the drawback that any warranty provided by the water heater manufacturer may be voided by virtue of the modification. Furthermore, reliance only on electronic control for turning off the electrical supply to a hot water heater may be insufficiently reliable due to electronic faults that may occur, making removal of an existing thermostat dangerous or at least inadvisable.

The applicant considers there to be room for improvement.

The preceding discussion of the background to the invention is intended only to facilitate an understanding of the present invention. It should be appreciated that the discussion is not an acknowledgment or admission that any of the material referred to was part of the common general knowledge in the art as at the priority date of the application.

SUMMARY OF THE INVENTION

In accordance with an aspect of the present disclosure there is provided a thermal adapter comprising a base and an elongate strip of thermally conductive material extending from the base, wherein the base is configured to be fitted at an opening of a thermostat pocket of a water heater with the elongate strip extending into the thermostat pocket, wherein the base provides an attachment point for a thermal sensor connected to the elongate strip, and wherein the elongate strip and the base are shaped to permit a thermostat rod to fit into the thermostat pocket alongside the elongate strip.

The base may be configured to connect around the opening of the thermostat pocket. The base may include an aperture through which the thermostat rod can extend.

The elongate strip may be made from a thin sheet of malleable or flexible material which, in use, conforms to an inner surface of the pocket, so as to permit the elongate strip to fit within existing tolerances between the thermostat rod and the thermostat pocket. The elongate strip may be shaped to have a flat profile. The flat profile may facilitate fitment of the strip alongside the thermostat rod in the thermostat pocket.

The elongate strip may have a base end and a distal end. The base may include a retaining formation for retaining the base end of the elongate strip. The attachment point may be provided by the retaining formation of the base.

In use, the distal end of the elongate strip may extend into the pocket.

The base may include a groove or recess shaped to permit the thermal sensor to be connected to the elongate strip, e.g., to the base end thereof. The groove may be a circumferential groove in the base. The groove may be shaped so as to enable a wire or cable to be connected to the elongate strip, e.g., to the base end thereof.

The elongate strip may be looped around the thermal sensor. For example, the base end of the elongate strip may be looped around the thermal sensor. The thermal sensor may be attached, e.g., to the base end of the elongate strip, for example by way of an adhesive such as a thermally conductive adhesive. The base end of the elongate strip may be substantially P-shaped. The elongate strip may, in use, be seated at the attachment point of the base. For example, the base end, or looped base end of the elongate strip may in use be seated in the groove at the attachment point or at the retaining formation of the base.

The base may include a slot that extends therethrough. The slot may extend from an outer side of the base to an inner side of the base. The slot may be provided in the groove or recess.

The elongate strip may pass through the slot in the base. The base end or looped base end of the elongate strip may be seated in the groove at the attachment point. The elongate strip may, in use, be looped back through the aperture in the base to extend away from the base. For example, the distal end of the elongate strip may, in use, be looped back through the aperture in the base to extend away from the base.

The elongate strip may be made from any thermally conductive material such as a metal or an alloy. For example, the elongate strip may be made from copper, zinc, or brass. The metal or alloy may be selected so as to be malleable or flexible.

The base may be made from a strong or tough material such as plastics, polymers, or metals. The base may for example be made from injection moulded plastics.

In accordance with another aspect of the present disclosure there is provided a water heater having a thermal adapter as defined above. The thermal adapter may be operatively connected to an external circuit arranged to receive sensor data or a sensor signal from the thermal sensor in use.

In accordance with yet another aspect of the present disclosure there is provided a method of manufacturing a thermal adapter, the method comprising: providing an elongate strip of thermally conductive material, the elongate strip having a base end and a distal end; connecting a thermal sensor to the base end; providing a base configured to be fitted at an opening of a thermostat pocket of a water heater, the base having an aperture through which a thermostat rod can extend and a slot extending at least partially through the base, the base providing an attachment point for the elongate strip with its connected thermal sensor; passing the elongate strip through the slot so that the base end is located at the attachment point; and looping the distal end through the aperture so as to be capable of extending into the thermostat pocket in use.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

Figure 1 is a three-dimensional view of a thermal adapter as viewed from an inner side thereof, illustrating an elongate strip of thermally conductive material extending from a base;

Figure 2 is a three-dimensional view of the thermal adapter of Figure 1 as viewed from an outer side thereof;

Figures 3-4 are three-dimensional views illustrating exemplary steps in an assembly of the thermal adapter;

Figure 5 is a three-dimensional view of the base of Figure 1 as viewed from an outer side thereof;

Figure 6 is a three-dimensional view of the base of Figure 5 as viewed from an inner side thereof;

Figure 7 is a plan view of the base of Figure 5, as viewed from its outer side;

Figure 8 is a plan view of the base of Figure 5, as viewed from its inner side;

Figure 9 is a three-dimensional view of the elongate strip of Figure 1 , illustrating a thermal sensor and wire connected thereto;

Figures 10-1 1 are diagrammatic representations of exemplary steps of forming the elongate thermally conductive strip;

Figure 12 is an exploded three-dimensional view, illustrating an assembly of an exemplary thermal adapter that is installed or retrofitted to a thermostat pocket of an existing water heater;

Figures 13-14 are exploded and assembled three-dimensional views of the assembly of Figure 12; and

Figure 15 is a high-level flow diagram of an exemplary method of manufacturing a thermal adapter.

DETAILED DESCRIPTION WITH REFERENCE TO THE DRAWINGS

There is disclosed a water heater and a mounting structure with a temperature measuring device for a water heater. The mounting structure may also be termed a base or a collar, and the mounting structure with temperature measuring device may also be referred to as a thermal adapter or a temperature probe. An elongate member or elongate strip or plate of thermally conductive material may extend from the base. The elongate member may be attached or affixed to the base and it may extend away from the base into a thermostat pocket of a water heater. The thermostat pocket may also be termed a thermostat tube or bore, and it may enable a thermostat rod to be inserted therein.

In use, the elongate member may extend into the thermostat pocket, and the base may be configured to permit a thermal sensor to be connected to a proximal end or base end of the elongate member. The elongate member and base may be shaped to permit the thermostat rod to fit into the thermostat pocket alongside or adjacent to the elongate member. In use, heat may be transferred along the length of the elongate member, so that the proximal or base end of the elongate member reaches a temperature which is near the temperature of the thermostat rod. Stated differently, the proximal or base end of the elongate member may reach an operative temperature that may provide an estimation of the temperature of the thermostat rod along its length.

In Figures 1 and 2 are shown an example embodiment of a thermal adapter (10). In the present embodiment, the thermal adapter (10) includes a base (12) and an elongate strip (14) of thermally conductive material extending from the base (12). The base (12) may be configured to be fitted at an opening (16) of a thermostat pocket (18) of a water heater (20). In this regard, see Figure 12 in which part of the water heater is shown for exemplary purposes. In use, the elongate strip (14) may extend into the thermostat pocket (18). The base (12) may provide an attachment point (22) (see Figure 8) for a thermal sensor (24) connected to the elongate strip (14). The elongate strip (14) and the base (12) may be shaped to permit a thermostat rod (26) to fit into the thermostat pocket (18) alongside the elongate strip (14).

The elongate strip (14) may have a base end (28) and a distal end (30). In the present embodiment, the elongate strip (14) is made from a thin sheet of malleable or flexible material which conforms to an inner surface of the pocket (18). This may permit the elongate strip (14) to fit within existing tolerances between the thermostat rod (26) and the thermostat pocket (18). The thermostat pocket may be an elongate tube extending into the water heater (20) as is well known in the art. For example, the thermostat pocket (18) includes the elongate tube which extends near an exemplary heating element or heating coil (32) of the water heater (20). In the exemplary embodiment in Figure 12, the heating coil extends around the thermostat pocket (18) and its tube. This may for example enable the thermostat to measure water temperature in a region of the coil (32). However, it will be appreciated that the heating element may also be replaced with another heating device, such as a gas-powered heat exchanger or another type of heat exchanger. The present disclosure extends to measuring temperature in a thermostat pocket associated with other types of water heaters such as gas water heaters.

The elongate strip (14) may be shaped to have a flat profile. The flat profile may facilitate fitment of the strip alongside the thermostat rod (26) in the thermostat pocket (18). The elongate strip (14) may be made from any thermally conductive material such as a metal or an alloy. For example, the elongate strip may be made from copper, zinc, or brass. The thermal conductivity of the elongate strip may facilitate heat transfer from its distal end (30) to its base end (28) by conduction. The metal or alloy that the elongate strip (14) is made from may be selected so as to be malleable or flexible. This may facilitate the elongate strip to deform, flex or bend when the thermostat rod is inserted adjacent to it in the thermostat pocket (18) as will be described in more detail below with reference to Figures 12-14. The elongate strip may be arranged to conform to the inner surface of the pocket (18), as well as to an outer surface of the thermostat rod (26) when the elongate strip and thermostat rod are inserted into the thermostat pocket (18), so as to extend alongside one another in use.

The base (12) may be configured to connect around the opening (16) of the thermostat pocket (18). As shown in Figures 1 -8, in the present embodiment, the base includes an aperture (34) through which the thermostat rod (26) can extend in use (see Figures 13-14). The thermostat pocket may have a projecting portion (see Figure 12), and the aperture (34) of the base (12) may be shaped to receive the projecting portion of the thermostat pocket (18) so as to fit the base (12) to the thermostat pocket (18). The elongate strip (14) may also extend through this aperture (34) as will be explained in more detail below. In use, the distal end (30) of the elongate strip (14) may extend into the thermostat pocket (18) adjacent to, or alongside the thermostat rod (28).

The base (12) may include a groove (36) or recess shaped to permit the thermal sensor to be connected to the elongate strip (14), e.g., to the base end (28) thereof. The groove may be a circumferential groove in the base, and it may be shaped so as to enable a wire (38) or cable to be connected to the elongate strip (14). The wire may, e.g., be connected to the base end (28) of the elongate strip (14). Only a portion of the wire (38) is shown, for the sake of brevity, as indicated by the break lines in Figures 1 -4, 9, and 12-14. For a similar reason, only a portion of the length of the thermostat rod and elongate strip is shown in Figures 12-13 as indicated by break lines in those Figures.

Figures 9-11 illustrate the elongate strip (14) and an exemplary method of its manufacture or formation. The elongate strip (14) may be elongated, and it may be in the form of a flat plate of thermally conductive material as described herein. As seen in Figure 10, the elongate strip (14) may be looped, partially looped or curved around or substantially around the thermal sensor (24). For example, the base end (28) of the elongate strip may be looped around the thermal sensor (24). The thermal sensor may be any sensor capable of sensing temperature, e.g. sensing temperature electrically. The sensor may be a thermoelectric sensing device, such as a thermocouple or a bi-metallic thermocouple. The thermal sensor (24) may for example be a K- type thermocouple with its associated wire. The thermal sensor (24) may be attached, e.g., to the base end (28) of the elongate strip (14), for example by way of an adhesive such as a thermally conductive adhesive. Thermal epoxy may, for example, be used for this purpose, but it will be appreciated that any other type of adhesive or joining method may be used. For example, embodiments may be possible in which the sensor is directly connected to the elongate strip (14), e.g. by soldering or another type of fastening or connection. The base end (28) of the elongate strip (14) may be substantially P-shaped, as illustrated diagrammatically in Figure 10, with the sensor located in the rounded part, hooked part, or partial loop of the P-shape. A base portion of the elongate strip may also be thermally insulated so as to inhibit ambient temperature from affecting the sensed temperature.

As shown in Figure 8, the base (12) may define the attachment point (22) whereat the thermal sensor (24) may be located in use. The attachment point (22) may also be termed a retaining formation, or the attachment point may be provided by the retaining formation of the base (12). The elongate strip (14) may, in use, be seated at the attachment point (22) of the base (12). The base end (28) of the elongate strip (14) may, in use, be seated in the groove (36) at the attachment point (22) or retaining formation of the base (12). Stated differently, the base (12) may include the retaining formation (22) for retaining the base end (28) of the elongate strip (14).

As can be seen in Figures 5 and 8, the base (12) may also include a slot (40) that extends through the base (12), or at least partially through the base (12). In the present embodiment, the slot (40) extends from an outer side (42) of the base (12) to the groove (36). In other words, the slot may extend from an outer side (42) of the base to an inner side (44) of the base (12). The slot may be provided in the groove (36) or recess. The groove (36) is also indicated by broken lines in Figure 7 for the sake of clarity.

Referring to Figures 2 to 4, in an exemplary assembly process of the thermal adapter (10), the elongate strip (14) may be passed through the slot (40) in the base (12), with the base end (28) of the elongate strip (14) seated in the groove (36) at the attachment point (22) or retaining formation of the base (12). The elongate strip (14) may be looped back through the aperture (34) in the base (12) to extend away from the base (12). For example, the distal end (30) of the elongate strip (14) may, in use, be looped back through the aperture (34) in the base (12) to extend away from the base. An exemplary operative configuration of the thermal adapter (10) is illustrated in Figure 2. To bring the elongate strip (14) into this position, the elongate strip (14) may be inserted through the slot (40) in the groove as illustrated in Figure 3, and the base end (28) may be drawn in the direction of directional arrow (46) towards the slot (36) until the loop of the base end (28) (in the case of the base end being looped), or the base end itself is seated in the groove (36) at the attachment point (22) or retaining formation (shown in Figure 8). The attachment point (22) or retaining formation may function to retain the base end of the elongate strip securely in the base (12). Once the base end (28) of the elongate strip (14) is seated or located at the attachment point (22), the distal end (30) may be looped back or looped around through the aperture (34) as illustrated in Figure 4. Figure 4 is for demonstrative purposes, and it will be appreciated that the distal end may also be looped back through the aperture (34) before the base end is completely seated at the attachment point. Either way, once the distal end (30) is pulled away from the base, the base end (28) may be drawn into the groove so as to fit tightly inside the groove at the attachment point or retaining formation adjacent to the slot (40).

In the present embodiment, the slot (40) may be smaller in size than the base end (28) of the elongate strip (e.g. with its attached thermal sensor (24)), and this may cause the base end (28) to be lodged or wedged into the groove adjacent to the slot, when the elongate strip is pulled in the direction of directional arrow (46). Also, if the elongate strip is pulled in the direction of directional arrow (48) in Figure 4, it may further cause the base end (28) to become seated, lodged, located or securely positioned at the slot. In other words, the sizing of the slot (40) and the configuration of the retaining formation (22) may cause the base end (28) of the elongate strip (14) to be secured to the base (12). Once the distal end (30) is pulled through the aperture (34) enough, the elongate strip may reach the position as shown in Figure 2. The wire (38) may also be located securely in the circumferential groove (36).

The base may be made from a strong or tough material such as plastics, polymers, or metals. The base may for example be made from injection moulded plastics, additive manufacturing or subtractive manufacturing such as machining. However, other types of materials or manufacturing methods may also be used, as will be appreciated by those skilled in the art.

Turning now to Figure 12, once the thermal adapter (10) has been assembled and/or manufactured, it may be installed or retrofitted to a water heater (20). An exemplary water heater is shown in Figure 12, but it will be appreciated that many other types of water heaters are possible. The thermostat pocket (18) is typically a tube having an outer opening (16). Normally, the thermostat rod (26) may have an outer housing (50) for electrical components, and it may have an adjustable temperature dial (52) for adjusting the temperature setting of the water heater (20). The thermostat rod (26) is conventionally inserted into the opening (16) of the thermostat pocket (18), and the outer housing (50) may be clipped onto a faceplate (54) by clips (56). In the present embodiment, the thermal adapter (10) may be inserted into the thermostat pocket (18), with its distal end (28) extending into the thermostat pocket and away from the base (12). This is demonstrated by broken lines in Figure 13. The thermostat rod (26) may also be inserted into the thermostat pocket, with the thermostat rod (26) extending alongside the elongate strip (14) of the thermal adapter (10), as illustrated by broken lines in Figure 14. The thermostat rod (26) may be passed through the aperture (34) in the base (12) adjacent to the base end (28) of the elongate strip. This may also facilitate the elongate strip (14) to be pulled tightly with the base end (28) seated at the attachment point (22), by virtue of friction between the thermostat rod and the elongate strip. Moreover, the pliable, malleable or flexible characteristics of the elongate strip (14) may facilitate it to conform to the shape of the thermostat rod, and/or for it to conform to the shape of an inner surface of the thermostat pocket.

Referring again to Figures 1 -2, and 12-13 the base (12) may have a recess or cut-out (68) which is shaped to accommodate another device such as a fastener to extend past. The cut-out (68) may for example enable a fastener to fasten the thermostat housing (50) to the faceplate (54), or a fastener for the heating element may extend past the cut-out (68). In an example embodiment, the cut-out may enable a cap screw of the faceplate (54) to extend past the base (12). The faceplate (54) may also be referred to as an element flange (i.e. a flange that mounts the heating element (32) to the water heater vessel). The fastener may for example fasten the heating coil to a body of the water heater. The base (12) may be friction fitted to the faceplate (54), or a friction fit may be implemented between the base (12), the thermostat rod (26) and the thermostat pocket (18). The recess (68) may also be shaped to abut against the fastener or cap screw, or against another component of the thermostat, so as to inhibit rotation or pivotal movement of the base (12). Inhibiting rotation or pivotal movement of the base may be advantageous, because it may prevent the elongate strip (14) from twisting or breaking. Moreover, inhibiting rotation of the base by way of the cut-out (68) may also keep the wire (38) securely in its desired position (i.e. inhibiting the wire from moving). This may inhibit the wire from breaking due to inadvertent pivotal movement of the base. A slight friction fit between the fastener and the recess, cut-out or notch may also maintain the thermal adapter assembly in position during a thermostat rod re-fitment process.

The present disclosure extends to a water heater (20) having a thermal adapter (10), the thermal adapter (10) being connected to an external circuit (58) arranged to receive sensor data or a sensor signal from the thermal sensor (10) in use. The external circuit (58) may be arranged to control on, and off switching of the water heater. An exemplary high level block diagram of the external circuit (58) is shown in Figure 12. The external circuit (58) may include a processor (60), a memory (62), and a receiver (64). Temperature data, a sensor signal(s), or other sensor data from the thermal adapter (10) may be transmitted to the external circuit (58) where it may be received by the receiver (64). The external circuit (58) may also include a switching component (65) arranged to switch the water heater on or off, so as to keep the water temperature in a selected operating range, or so as to keep the water temperature near a desired operating temperature. This selected operating temperature may be lower than a set temperature of the thermostat rod which can be adjusted by the dial (52) for example. The switching component (65) may for example provide power to the heating coil (32) or it may shut it off. The thermal sensor (24) may be configured to measure temperature of the elongate strip (14), for example at the base end (28) of the elongate strip (14). This temperature measurement may be indicative of a temperature of the thermostat rod (26), or the temperature measurement may be indicative of an average temperature of the thermostat rod (26), due to the good thermal conductivity of the elongate strip (14). The elongate strip may also be malleable and flexible, and due to its flexible and malleable properties, it may extend alongside the thermostat rod without being damaged by the thermostat rod. This may alleviate problems that may be associated with inserting a temperature measuring wire into the thermostat pocket.

The present disclosure may also enable the thermal adapter to be retro-fitted to existing water heaters or the thermal adapter may be installed during manufacture of the water heater. The thermal adapter may be installed or retro-fitted to water heaters without alteration of the thermostat rod or thermostat housing. The existing thermostat can then be set to its highest shut off temperature (e.g. 75 degrees Celsius), with the control circuit’s set temperature being lower, as a safety feature so that even if the control circuit or sensor fails, the existing thermo-mechanical thermostat will cut off at this shut off temperature and thereby prevent damage. The invention therefore preserves the existing safety feature of the water heater (the thermostat) and requires no modification to the water heater other than the insertion of the elongate strip of the thermal adapter which does not interfere at all with the functioning of the thermostat.

In other words, the switching component (65) of the external circuit (58) may be arranged to receive near-real time temperature data or sensor signal(s) from the sensor (24), so that the water temperature of the water heater (20) may be controlled by the external circuit (58) so as to be near a set temperature of the external circuit (58). This set temperature of the external circuit may be lower than the set temperature of the thermostat rod (26), so that the existing thermostat and its thermo-mechanical shut off may act as a back-up safety mechanism, in case any of the components of the external circuit or the sensor itself fail for any reason. It will also be appreciated that the thermostat pocket may extend centrally inside the heating coil as shown in Figures 12-14, however, embodiments are possible in which the thermostat pocket, aperture or tube extends from another location into the water heater or vessel. The present disclosure may enable solar powered water heating systems or other water heater controllers to receive temperature feedback, temperature sensing data or sensed signal(s) from the thermal adapter of the water heater, so as to control heating efficiently and accurately. The external circuit may for example form part of such a water heater control system.

In Figure 15 is shown a high-level flow diagram of an exemplary method (100) of manufacturing a thermal adapter (10). The method may include providing (102) an elongate strip (14) of thermally conductive material, the elongate strip having a base end (28) and a distal end (30). The method (100) may further include connecting (104) a thermal sensor (24) to the base end (28). The method may include the step of providing (106) a base (12) configured to be fitted at an opening (16) of a thermostat pocket (18) of a water heater (20), the base (12) having an aperture (34) through which a thermostat rod (26) can extend and a slot (40) extending at least partially through the base (12), the base providing an attachment point (22) for the elongate strip (14) with its connected thermal sensor (24). The method may include passing (108) the elongate strip (14) through the slot (40) so that the base end (28) is located at the attachment point (22). The method may further include looping (110) the distal end (30) through the aperture (34) so as to be capable of extending into the thermostat pocket (18) in use.

The foregoing description has been presented for the purpose of illustration; it is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Persons skilled in the relevant art can appreciate that many modifications and variations are possible in light of the above disclosure. The language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter. It is therefore intended that the scope of the invention be limited not by this detailed description, but rather by any claims that issue on an application based hereon. Accordingly, the disclosure of the embodiments of the invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.

Finally, throughout the specification and accompanying claims, unless the context requires otherwise, the word ‘comprise’ or variations such as ‘comprises’ or ‘comprising’ will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Claims

CLAIMS:

1. A thermal adapter (10) comprising a base (12) and an elongate strip (14) of thermally conductive material extending from the base (12), wherein the base (12) is configured to be fitted at an opening (16) of a thermostat pocket (18) of a water heater (20) with the elongate strip (14) extending into the thermostat pocket (18), wherein the base (12) provides an attachment point (22) for a thermal sensor (24) connected to the elongate strip (14), and wherein the elongate strip (14) and the base (12) are shaped to permit a thermostat rod (26) to fit into the thermostat pocket (18) alongside the elongate strip (14).

2. The thermal adapter (10) as claimed in claim 1 , wherein the base (12) is configured to connect around the opening (16) of the thermostat pocket (18).

3. The thermal adapter (10) as claimed in claim 1 or claim 2, wherein the elongate strip (14) is made from a thin sheet of flexible material which, in use, conforms to an inner surface of the thermostat pocket (18), so as to permit the elongate strip (14) to fit within existing tolerances between the thermostat rod (26) and the thermostat pocket (18).

4. The thermal adapter (10) as claimed in any one of the preceding claims, wherein the elongate strip (14) has a base end (28) and a distal end (30), wherein the base (12) includes a retaining formation for retaining the base end (28) of the elongate strip (14), and wherein the attachment point (22) is provided by the retaining formation of the base (12).

5. The thermal adapter (10) as claimed in any one of the preceding claims, wherein the base (12) includes a groove (36) shaped to permit the thermal sensor (24) to be connected to the elongate strip (14).

6. The thermal adapter (10) as claimed in claim 5, wherein the groove (36) is shaped so as to enable a wire (38) to be connected to the elongate strip (14).

7. The thermal adapter (10) as claimed in any one of the preceding claims, wherein the elongate strip (14) is in use seated at the attachment point (22) of the base (12).

8. The thermal adapter (10) as claimed in any one of the preceding claims, wherein the base (12) includes a slot (40) that extends therethrough, and wherein the elongate strip (14) passes through the slot (40) in the base (12).

9. The thermal adapter (10) as claimed in any one of the preceding claims, wherein the base (12) includes an aperture (34) through which the thermostat rod (26) can extend.

10. The thermal adapter (10) as claimed in claim 9, wherein the elongate strip (14) is, in use, looped back through the aperture (34) in the base (12) so as to extend away from the base (12).

1 1. The thermal adapter (10) as claimed in any one of the preceding claims, wherein the elongate strip (14) is looped around the thermal sensor (24).

12. The thermal adapter (10) as claimed in any one of the preceding claims, wherein the elongate strip (14) is made from a thermally conductive material.

13. The thermal adapter (10) as claimed in any one of the preceding claims, wherein the base (12) is made from injection moulded plastics.

14. A water heater (20) having a thermal adapter (10) as claimed in any one of claims 1 to 13, wherein the thermal adapter (10) is connected to an external circuit (58) arranged to receive a sensor signal from the thermal sensor (24) in use.

15. A method (100) of manufacturing a thermal adapter (10), the method comprising: providing (102) an elongate strip of thermally conductive material, the elongate strip having a base end and a distal end; connecting (104) a thermal sensor to the base end; providing (106) a base configured to be fitted at an opening of a thermostat pocket of a water heater, the base having an aperture through which a thermostat rod can extend and a slot extending through the base, the base providing an attachment point for the elongate strip with its connected thermal sensor; passing (108) the elongate strip through the slot so that the base end is located at the attachment point; and looping (1 10) the distal end through the aperture so as to be capable of extending into the thermostat pocket in use.