GB2386408A

GB2386408A - Water heater with scale removal

Info

Publication number: GB2386408A
Application number: GB0205854A
Authority: GB
Inventors: Robin Edward Brash
Original assignee: Triton PLC
Current assignee: Triton PLC
Priority date: 2002-03-13
Filing date: 2002-03-13
Publication date: 2003-09-17
Anticipated expiration: 2022-03-13
Also published as: GB0205854D0; IE20030091A1; GB2386408B

Abstract

The heater 300 has a housing vessel 301 containing a heating element 302, a water inlet 308, and a water outlet 309. A trap or container 305 collects lime-scale or other mineral deposits that build up inside the housing during use of the heater. The trap may be isolated from the housing by a removable cover 310. The cover may be operated by a manual, 311, or automatic control. A sensor 312 may be used to monitor the level of deposits in the trap and alert a user via an indicator device 313. The automatic control can be configured to isolate the trap when full of deposits. A suction device may be used to remove the deposits from the trap when isolated. The heater may be used in an instantaneous electric water heater device such as used in a shower unit.

Description

238640SS

-1 WATER HEATER DEVICE

Field of the Invention

The present invention relates to a means and method of removing deposits 5 from within an instantaneous electrical water heater device, and particularly, although not exclusively, from within such a water heater device operative within a shower unit.

Background to the Invention

To In order to heat water to be supplied for domestic and industrial sanitary purposes, it is known to use a suitable heating coil or element located within a housing vessel within which water is heated. Typically, water is allowed to enter and exit the housing vessel or water tank such that the water exiting the tank or vessel is substantially heated with respect to the water that enters the vessel or 5 tank. Water heaters, of the kind described above, are commonly used within shower units of the kind illustrated in Fig. 1. Typically, the water heater is located within a shower unit 100 which in turn may be mounted onto the wall of a shower 2 o cubicle 101.

Fig. 2 further illustrates a shower unit of the type known in the art. Fig. 2 illustrates a prior art shower having water heater unit 100 comprising a housing

vessel 200 located within its main body. Housing vessel 200 incorporates a 25 heating element 201 used to heat the water within the vessel 200. Water enters the shower heater unit and housing vessel via suitable water inlet piping 202.

Water flows through inlet piping 202, housing vessel 200 and outlet piping 204 to be expelled at the shower head as a heated spray of water. Water, on passing through heating vessel 200, is heated by heating element 201 before being 3 o expelled at 205.

-2 A well-known problem associated with the use of such water heating devices, forming part of the art, is the production of deposits, and in particular the deposits of mineral compounds, (e.g. calcium and magnesium salts) within the housing vessel 200 of the device. Such deposits are commonly known as "scale". Conventional water heating devices fail due to large build up of scale.

The problem associated with the formation of salt deposits within water heating devices varies in magnitude depending upon the type of water supplied to the device. A type of water termed hard water, contains a high concentration of dissolved mineral compounds, such that water heater devices operable within To hard water geographical regions can quickly become blocked and unusable due to the production and build up of salt deposits within its interior.

The hardness of the water is a result of, in particular calcium bicarbonate dissolved in the water. On heating, this forms calcium carbonate which is :s insoluble and is precipitated. The process is illustrated below as: Heat Ca(HCO3)2 > CaCO3 + H2O + CO2 Typically, these precipitated deposits are known as limescale or scale and are increased with the increase in temperature of the water. The build up of go scale, for example in hard water areas, on the heating element 201 and housing vessel 200, significantly reduces the efficiency of the water heater device.

Moreover, the build up of scale on a heating element 201 causes excessive heating in a specific locality of the heating element surface this localised non-

uniform heating considerably reduces the lifespan of the heating element.

Some prior art shower units are known to have heater can assemblies

which comprise a housing vessel having a removable lid, such that when the housing vessel dis-assembled, the heating element and lid can be separated from a remaining body of the housing vessel, to allow cleaning of the housing o vessel and heater element separately. However, this requires taking a casing off

-3 the prior art shower unit, to access the internal components of the shower unit

including the housing vessel. This requires a service engineer call out, and the service engineer must perform several operations including removing the shower casing, and dis-assembly of the heater can in order to remove scale deposits from the shower unit.

At present, the inventors are unaware of any prior art solution for removing

build up of scale deposits from within a housing vessel heating water within a water heater device of the type used for the sanitary shower installations.

The inventors have realised means and method for removing salt deposits or scale from a water heater device without the need to dismantle most of the device, such that the interior of the device and in particular the heating element 201 do not become encrusted and damaged due to the build up of salt deposits or scale. Such an invention is described herein below in detail.

Summarv of the Invention The inventors have realised means and method for removing salt deposits or scale from the interior of a water heater device, and in particular, a device to o heat water forming part of a shower or shower unit. As the magnitude with which salt deposits or scale are built up on the interior of a housing vessel, particularly in hard water geographical areas, large amounts of deposits form on the heating element and interior of the housing vessel.

According to one specific implementation of the present invention a collecting trap is connected to a housing vessel such that salt deposits or scale precipitated out of the water within the housing vessel, settle into the collecting trap whereby these deposits may be removed from the water heater device. The removal of such salt deposits from the collecting trap is possible without the need so to substantially dismantle the heater unit. A releasably sealable orifice may be provided in the collecting trap such that easy access may be gained to the trap from a position outside of a shower unit its interior. A water heater device

-4 - according to the specific implementation of the present invention thereby considerably reduces the time required to remove salt deposits from the interior of such a housing vessel.

5 According to further specific implementations of the present invention isolation means are provided such that a housing vessel, within which the water is heated, may be isolated from a collecting trap and collected salt deposits.

isolation means are provided to prevent the salt deposits from reentering the housing vessel once collected in the collecting trap.

Further specific implementations of the present invention include the use of a contents meter being located within the collecting trap, such a contents meter being operative to monitor the magnitude of salt deposits collected in the collecting trap Moreover, salt deposits may be removed from the water heater device 300 by a user of the device without the requirement of a skilled technician to dismantle and clean the interior of the device.

2 0 According to a first aspect of the present invention there is provided a water heater device, said device comprising: a housing vessel for the heating of water passing through said device; 2 5 a heating element positioned within said housing vessel to heat water substantially within said housing vessel; and a collecting trap being connected to said housing vessel to collect deposits from said housing vessel.

Preferably, said collecting trap is formed on a lower portion of said housing vessel.

-5 Preferably, said collecting trap is formed integrally with said housing vessel.

Preferably, said collecting trap is releasably connected to said housing 5 vessel.

Preferably, said collecting trap may be indirectly connected to said housing vessel. to Preferably, said collecting trap further comprises a releasably sealable orifice, an interior of said trap being accessable through said orifce.

Preferably, said device further comprises: isolation means being positioned between said housing vessel and said collecting trap, said isolation means being configured to isolate said collecting trap from said housing vessel; wherein deposits within said collecting trap are substantially prevented from 2 o re-entering said housing vessel.

Preferably, said isolation means may be manually operated.

Preferably, said isolation means may be automatically operated.

Preferably, said collecting trap further comprises: a contents meter, wherein said contents meter is configured to monitor the magnitude of deposits collected in said trap.

Said device may further comprise:

-6 an indicator, said indicator being configured to indicate when said collecting trap is substantially full of deposits.

Said housing vessel may further comprise: guide means, said guide means being configured to guide said deposits from said housing vessel substantially into said collecting trap.

Preferably, wherein said housing vessel further comprises: at least one orifice configured to allow water to enter said vessel; and at least one orifice configured to allow water to exit said vessel, wherein said housing vessel is configured to allow a flow of water through said device.

Preferably, said collecting trap is configurable for connection to a suitable suction device, said suction device being operable to remove said deposits from 2 o said collecting trap.

Preferably, said device is configurable to heat water for use in a shower unit. Preferably, said device is configurable to be operative within a shower unit.

Preferably, said device is configurable to be operative within a wall mounted shower unit.

30 According to a second aspect of the present invention it is provided a method of storing and removing deposits from within a water heater device, said method comprising the steps of:

-7 providing a housing vessel with a collecting trap to collect deposits from said housing vessel; 5 heating water within said housing vessel using a heating element; collecting deposits from said housing vessel in said collecting trap; gaining access to an interior of said collecting trap; and removing said deposits from said collecting trap.

Typically said deposits are salt deposits.

Preferably the method further comprises the step of: monitoring a magnitude of deposits collected in said collecting trap using a contents meter positioned substantially within said collecting trap.

o Preferably the method further comprises the step of: indicating to a user of said device when said collecting trap is substantially full of deposits using an indicator.

Preferably the method further comprises the steps of: inputting a flow of water into said housing vessel using at least one water entry orifice; and 30 outputting a flow of water out of said housing vessel using at least one water exit orifice.

-8 Other aspects of the invention are as recited in the claims herein.

Brief Description of the Drawings

For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodinnents, methods and processes according to the present invention with reference to the accompanying drawings in which: Fig. 1 illustrates a typical shower unit known in the art; Fig. 2 illustrates a typical shower unit known in the art having a heating element and internal housing vessel; Fig. 3 illustrates schematically a specific implementation of the present invention having a heating element, housing vessel and collecting trap; for collection of scale deposits for within the housing vessel; Fig. 4 illustrates a flow diagram detailing a method of operation of the water heater device according to a specific implementation of the present invention; 2 0 and Fig. 5 illustrates a housing vessel and collection trap with a suitable sealing cap according to a specific implementation of the present invention; 2 5 Detailed Description of the Best Mode for Carrvinn Out the Invention

There will now be described by way of example the best mode contemplated by the inventors for carrying out the invention. In the following description numerous specific details are set forth in order to provide a thorough

understanding of the present invention. It will be apparent however, to one skilled 3 o in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to unnecessarily obscure the present invention.

-9 - Referring to Fig. 3 herein there is illustrated part of a water heater unit 300 having housing vessel 301. Housing vessel 301 is constructed from a material suitable to withstand elevated temperatures and to resist corrosion due to the 5 presence of water at elevated temperatures.

The heating vessel 301 contains a heating element 302 for heating water passing through the heating vessel, the heating element comprising a centrally located heating wire of high electrical resistance, surrounded by a suitable To powdered insulating material, and encased in a tubular outer casing; an inlet orifice 308 for inletting water into the heating vessel; an outlet orifice 309 for outletting water from the heating vessel; a collecting trap 305 located at a lower end of the housing vessel for collecting scale deposits which build up internally of the heating vessel during use; an isolator 310 for isolating the trap 305 from a main interior chamber of the heating vessel 301, such that when the isolator is in a closed position, the internal chamber of the heating vessel 301 is isolated from an interior of the collecting trap 305, and when the isolated 310 is in an open position, internal chamber of heating vessel 301 is in communication with an interior of the collecting trap 305, so that scale deposits falling away from heating o element 302 can settle into the collecting trap 305 under force of gravity; and an indicator device 312, 313 for indicating a build up of scale deposit within the collecting trap 305.

The temperature of the water exiting orifice 309 may be controlled by the controlling of the flow of water through orifice 308 using a suitable valve 306. For example, with valve 306 fully open, and a corresponding rapid flow of water through vessel 301, water exits orifice 309 being partially heated due to a reduced exposure to heating element 302. Conversely, if valve 306 is only partially open, thereby restricting the flow of water into vessel 301, water within o 301 is exposed to element 302 for a extended period and exits orifice 309 at an elevated temperature with respect to water exiting orifice 309 with valve 306 fully

-10 opened. In addition, or alternatively, the temperature of water exiting orifice 309 may be controlled by the varying of power supplied to the heating element 302.

Connected to housing vessel 301 is collecting trap 305. According to the specific implementation of the present invention collecting trap 305 is located 5 substantially toward the lower portion of the housing vessel 301. Fig. 3 illustrates the collecting trap 305 being connected directly to the housing vessel 301.

In further specific implementations of the present invention trap 305 is formed integrally with said housing vessel, such that trap 305 and housing vessel To 301 may not be separated. According to further specific implementations of the present invention trap 305 is releasably connected to housing vessel 301, such connection being a direct connection. In yet a further specific implementation connection between trap 305 and vessel 301 is indirect, involving, for example, the use of suitable piping.

In the specific implementation of the present invention the water heater device is provided with guide means 307. Guide means 307 are configured to guide the salt deposits formed on the heating element 302 and interior of housing vessel 301, into the collecting trap 305. As the salt deposits travel to the lower 20 portion of the housing vessel 301, under the force of gravity, guide means 307 provide a funnel-like action, allowing the salt deposits to enter the collecting trap 305 where they remain.

Housing vessel 301 is configured with at least one orifice 308 which allows water to enter the vessel 301 and in turn be heated by the heating element 302.

Housing vessel 301 is also configured with at least one orifice 309 which allows water to exit the vessel. Water entry orifice 308 and water exit orifice 309 are operable to allow a constant flow of water through the housing vessel 301 such that water enters the vessel, is temporarily stored, and in turn heated by heating 3 o element 302.

-11 According to the specific implementation of the present invention device 300 is configured with isolation means 310. Isolation means 310 being operable to segregate or partition the housing vessel 301 from the collecting trap 305.

Isolating means 310 may be engaged when the collecting trap 305 is substantially full of salt deposits. Isolation means 310, when isolating the housing vessel 301 from the collecting trap 305, substantially prevent or restrict the passage of the salt deposits recentering the housing vessel 301. Isolation means 310 being constructed from a material suitable to block the passage of substantially solid salt deposits, such a material being for example: plastic; metal; o mesh; ceramic or glass.

Isolation means 310 according to the specific implementation of the present invention are connected to a manual controller 311, such that a user of the water heater device 300 selects to close isolation means 310 thereby isolating the 15 collecting trap 305 from the housing vessel 301. The connection between isolation means 310 and manual controller 311 is made by a suitable connecting wire 303. The isolation of the collecting trap 305 from the housing vessel 301 allows the interior of the trap 305 to be accessed without substantially perturbing the interior of the housing vessel 307. Isolation means 310 therefore allows the 2 0 water heater device to be cleaned of salt deposits or scale without the resort to substantially draining and dismantling the device so as to gain access to its interior and remove the salt deposits or scale from within.

In a further specific implementation of the present invention manual control 25 means 311 are replaced by automatic control means such that the water heater device 300 is configured to isolate the collecting trap 305 from the housing vessel 301 at any given predetermined time. Such a time may be, for example, when the collecting trap 305 is substantially full of salt deposits. Automatic control means can be configured to be operable in response to a suitable indicator within 3 o the water heater device 300.

-12 The water heater device 300 comprises an indicator or sensor 312.

Indicator 312 is operable to monitor the contents of collecting trap 305 and to indicate when the trap is substantially full of salt deposits. In operation, indicator 312 is triggered by the substantial contact with salt deposits whereby a user of 5 the heater device 300 is alerted, via a suitable indicator device 313, as to the magnitude of salt deposits contained within the trap. Indicator 313 according to a specific implementation of the present invention is a LED. In further specific implementations of the present invention indicator 313 is a suitable device configured to output a variety of readings thereby indicating a variety of levels of 0 magnitude of salt deposits collected within the collecting trap 305.

Referring to Fig. 4 there is illustrated a flow diagram of a mode of operation of the water heater device 300 according to the specific implementation of the present invention. The invention, when in operation, is configured to allow water to pass into the heater unit 300 at stage 400. The passage of water into the heater unit, and in particular into the housing vessel 301 is via at least one orifice 308 configured to allow water to enter the heater unit. Water within the heater unit, and in particular within the housing vessel 301 is heated by a suitable heating element 302 at stage 401. After the water is substantially heated water o exits the heater 300 and in particular the housing vessel 301 through at least one orifice 309 at stage 402.

Stages 400 to 402 are continually repeated when the device 300 is in operation to provide a constant supply of heated water. Over a period of time of operation salt deposits or scale in the form of calcium carbonates, for example, form on the interior of the device, and in particular on the interior of the housing vessel 301 and heating element 302 at stage 403. After a significant operational time period a substantial amount of salt deposits are produced within the interior of the device 300. At stage 404 the heater unit 300 allows the salt deposits, So produced on the heating element 302 and the interior of housing vessel 301 to settle in the collecting trap 305.

-13 According to the specific implementation of the present invention the heater device 300 is configured with a heating element 302 such that heating element 302 is configured to supply heat at a magnitude of more than above about 250 watts per square inch. The use of a high output heating element 302 is operative s to displace any salt deposits or scale produced on its surface. Effectively, the salt deposits are baked off the surface of the heating element 302 due to its substantial heating output. The salt deposits displaced from the surface of the heating element 302 travel down the housing vessel 301, under the force of gravity, to reside in the collecting trap 305. At stage 405 the collecting trap 305 is o isolated from the housing vessel 301 such that salt deposits collected in the trap 305 are not allowed to re-enter the main body of the heater unit 300. At stage 406 the salt deposits collected in the trap 305 are removed via a suitable orifice formed within the collecting trap body. Such an orifice is described in more detail below with reference to Fig. 5. The salt deposits may be removed manually from s within the collecting trap 305, for example, trap 305 may be configured for connection with a suitable suction device, such as a vacuum suction device, whereby the deposits are removed from the collecting trap 305 under partial vacuum. So At stage 407 isolation means 310 are removed whereby the interior of the collecting trap 305 is re-exposed to the interior of the heater unit 300 and in particular the housing vessel 301. Isolation means 310 are configured with suitable seals such that the collecting trap 305 and the housing vessel 301 may be repeatedly isolated by the re-activation of isolation means 310. At stage 408 the heater unit 300 is substantially free from salt deposits due to their removal via the collecting trap and its orifice. The removal of salt deposits from the interior of the heater device, using the collecting trap, eradicates the need to substantially dismantle the water heater device 300 to gain access to its interior and manually remove the salt deposits. The utilization of isolation means 310 allows the water so heater device 300 to be substantially full of water while the collecting trap is accessed and the salt deposits removed. There is therefore a substantial saving

-14 on time required to remove the salt deposits from the water heater device 300 with respect to water heater devices as found in the art.

Referring to Fig. 5, there is illustrated part of the water heater device 300 according to the specific implementation of the present invention. Fig. 5 illustrates the housing vessel 301 and the collecting trap 305 being located substantially at the lower portion of the vessel.

The interior of collecting trap 305 is accessible via an orifice located To substantially at one end, the orifice being releasably sealable by the use of a suitable sealing cap 500. The orifice is configured to receive the cap 500, according to the specific implementation of the present invention, via the use of interacting threads. A portion of the releasably sealable orifice is configured with a threaded portion such that a similar threaded portion of the cap 500 is :5 configured to interact with it whereby the sealing cap is capable of being screwed into or onto the collecting trap 305. The interacting threaded portions thereby providing a suitable water tight seal. Suitable rubber seals may also be provided on the sealing cap and the orifice of the collecting trap 305, whereby a water tight seal is sustainable. Sealing cap 500 is screwed on to the collecting trap 305 by go the use of a handle 501 configured to be large enough so as to be grasped by human fingers.

The threaded portion of the collecting trap 305 is configurable, according to the specific implementation of the present invention, to engage with a suitable suction device, such that the collecting trap 305 may be partially evacuated therefore resulting in the removal of any salt deposits from within its interior.

Additionally, the housing vessel 301 may also be partially evacuated if, for example, isolation means 310 were not engaged and the interiors of the trap 305 and vessel 301 were exposed to each other. Isolation means 310 are configured so with suitable rubber seals such that when engaged, the collecting trap 305 may be partially evacuated whilst the housing vessel 301 maintains a body of water.

-15 ln yet further specific implementations of the present invention, collecting trap 305 is sealed by cap 500 using suitable pins, nails or screws being inserted through cap 500 and into a suitable receiving portion of trap 305. Suitable rubber seals may also be provided for positioning between cap 500 and trap 305 thereby 5 providing a water tight seal.

In a yet further specific implementation of the present invention collecting trap 305 is releasably sealable to housing vessel 301 at point 502, such that following the separating of trap 305 from vessel 301 the interior of trap 305 may be accessed to manually remove salt deposits from the interior. As such, the 1C orifice located substantially at one end of trap 305 may provide a second orifice through which to gain access to the interior or trap 305 for the purpose of removing deposits.

Accordingly, there may be provided suitable rubber seals for positioning at 15 connecting point 502 so as to ensure a water tight seal is maintained between vessel 301 and trap 305.

Claims

-16 Claims:

1. An instantaneous electric water heater device, said device comprising: a housing vessel; a heating element positioned within said housing vessel to heat water substantially within said housing vessel; and a collecting trap being connected to said housing vessel to collect deposits formed within said housing vessel; wherein deposits formed within said housing vessel are collected within said collecting trap said collecting trap comprising a removable access cover.

2. The device as claimed in claim 1, wherein said collecting trap is formed on a lower portion of said housing vessel.

3. The device as claimed in claim 1 or 2, wherein said collecting trap o is formed integrally with said housing vessel.

4. The device as claimed in any one of clainns 1 to 3, wherein said collecting trap is releasably connected to said housing vessel.

5. The device as claimed in any one of clainns 1 to 3, wherein said collecting trap is indirectly connected to said housing vessel.

6. The device as claimed in any preceding claim wherein said collecting trap further comprises a releasably sealable orifice, an interior of said o trap being accessable through said orifce.

-17

7. The device as claimed in any preceding claim, wherein said device further comprises: isolation means being positioned between said housing vessel and said 5 collecting trap, said isolation means being configured to isolate said collecting trap from said housing vessel.

8. The device as claimed in claim 7, wherein said isolation means are manually operable.

9. The device as claimed in claim 7, wherein said isolation means are automatically operated.

10. The device as claimed in any preceding claim, wherein said 15 collecting trap further comprises: a contents meter, wherein said contents meter is configured to monitor the magnitude of deposits collected in said trap.

20

11. The device as claimed in any one of the preceding claims further comprising: an indicator, said indicator being configured to indicate when said collecting trap is substantially full of deposits.

12. The device as claimed in any one of the preceding claims, wherein said housing vessel further comprises: guide means, said guide means being configured to guide said deposits o from said housing vessel substantially into said collecting trap.

-18

13. The device as claimed in any one of the preceding claims, wherein said collecting trap is configurable for connection to a suitable suction device, said suction device being operable to remove said deposits from said collecting trap.

14. The device as claimed in any one of the preceding claims, wherein said device is configurable to be operative within an electric shower unit.

15. The device as claimed in any one of the preceding claims, wherein said device is configurable to be operative within a wall mounted shower unit.

16. A method of storing and removing deposits from within a instantaneous electric water heater device, said method comprising the steps of: 15 providing a heating vessel with a collecting trap to collect deposits from said heating vessel; collecting deposits from said heating vessel in said housing trap; 2 o gaining access to an interior of said collecting trap; and removing said deposits from said collecting trap.

17. The method as claimed in claim 16, further comprising the step of: monitoring a magnitude of said deposits collected in said collecting trap using a contents meter positioned substantially within said collecting trap.

18. The method as claimed in claim 17, further comprising the step of: indicating to a user of said device when said collecting trap is substantially full of deposits using an indicator.

-19

19. A method of storing and removing deposits from within a instantaneous electric water heater device, said method comprising: 5 collecting deposits in a collecting trap provided in a heating vessel of said device, during operation of said water heater device; gaining access to an interior of said collecting trap; and JO removing said deposits from said collecting trap.