IL169779A - Method of and means for producing hot water from a hot water boiler system - Google Patents

Description

169779/02 METHOD AND MEANS FOR PRODUCING HOT WATER FROM A HOT WATER BOILER SYSTEM .S u y , METHOD AND MEANS FOR PRODUCING HOT WATER FROM A HOT WATER BOILER SYSTEM Field of the Invention The present invention relates to the field of producing hot water. More particularly, the invention relates to a method of and means for producing hot water from a hot water boiler system.

Background of the Invention Over the last few years, the effective and efficient production of hot water has been become increasingly important. This is particularly the case as the cost of energy sources such fuels like liquid and gaseous fuels has been escalating lately.

Solar water heaters with electrical back- up cap acity are de signe d to store quite a large quantity of water due to the virtually "free energy" coming directly from the sun most of the year.

In case of shortage of hot water because of weather conditions or malfunction of the system, there is a need to use electrical energy in order to supply sufficient hot water for household use. The main problem with such an electrical back-up system is the large quantity of water, often all of the water present in the hot water tank, to be heated which means that a huge amount of electrical energy will be spent for long periods of time. Another difficulty is related to the inconvenience in determining the quantity of hot water and its temperature in the tank and in controlling the activity of switching on to have hot water available on time and switching off later on.

There are many solutions to these problems, some of them very simple such as* Using an additional small volume tank for electrically heating the water! using an instantaneous gas water heater in series with hot water line from the solar system tank.

Some solutions are covered by patents such as-Israeli patents Nos. 59569 dated 09/85, 16824 dated 02/64 and 78015 dated 12/89 that consist of a sleeve around the heating element which transfers the heated water toward the upper zone of the tank while throttling the flow by an orifice or external valve, 121064 dated 07/01 and 104768 dated 04/94 that consist of inter-layers or inter-dividers meant to avoid mixing of hot and cold water, 63300 dated 06/85, 63003 dated 06/85, 53083 dated 01/85 and 105097 dated 08/96 that consist of apparatus for forcing the hot water from the upper part of the tank through the heating element chamber, 59575 dated 12/83 and 119984 dated 05/00 that consist of apparatus preheating the water coming to the heating element sleeve from the area above the sleeve, 53971 dated 12/80 that consists of two heating elements - one at the bottom and one at the upper zone of the tank; US patents 4282421 dated 08/81 that consists of a heating element sleeve and a combination of heat exchangers for preheating the water; 4551613 dated 11/85 that consists of a heating element surrounding the pipe all along 218.S06 July 18, 2005 - 3 - up to the discharge outlet,' 4403137 dated 09/83 that consists of a sleeve perforated all along; 4514617 dated 4/85 and #6321036 dated 11/01 that consist of apparatus for producing hot water for consumption flowing through the sleeve.

While the above mentioned patents describe inventions relating to providing hot water for immediate consumption, none of them are concerned with limiting the amount of hot water available for instantaneous use. In addition, only little consideration is given in these patents to reducing the rate at which power is consumed to provide the required hot water.

There is therefore a need to provide a new and improved method of and apparatus for producing hot water wherein the disadvantages as outlined are reduced or substantially overcome.

It is therefore an object of the present invention to provide method of and means for producing hot water from a hot water boiler system, which increases efficiency of hot water production when compared to other methods or systems.

Other objects and advantages of the invention will become apparent as the description proceeds.

Summary of the Invention The present invention provides a method for producing hot water from a hot water boiler system comprising the steps of supplying water via an inlet line from an upper portion of a hot water boiler to a heating element 218.S06 July 18, 2005 - 4 - sleeve having a heating element so that the water is supplied to the heating element via a thermostat located in an inlet line of said heating element sleeve! providing a further hot water line which connects a hot water line outlet of said heating element sleeve to the upper portion of the hot water boiler wherein the height difference between the lower end of either of said inlet line or said further hot water line in the upper portion of said hot water boiler and the top of said hot water boiler define a hot water volume maintained hot by said heating element and available for substantially immediate use or consumption; and providing a hot water consumption line for extracting the hot water from the hot water boiler tank for hot water use or consumption. Preferably, the method includes a further step in an embodiment or embodiments of the present invention of using a flow switch and an external thermostat external to the hot water boiler located on the hot water consumption line for increasing the temperature of the hot water extracted during hot water consumption while maintaining a substantially low average temperature in the hot water boiler.

In addition, the present invention provides apparatus for producing hot water from a hot water boiler system comprising: an inlet line for supplying water from an upper portion of a hot water boiler to a heating element sleeve having a heating element so that the water is supplied to the heating element via a thermostat positioned in an inlet line of said heating element sleeve! a further hot water line which connects a hot water line outlet of the heating element sleeve to the upper portion of the hot water .s u y , - 5 - boiler wherein the height difference between the lower end of either of said inlet line or said further hot water line in the upper portion of said hot water boiler and the top of said hot water boiler define a hot water volume maintained hot by said heating element and available for substantially immediate use or consumption; and a hot water consumption line for extracting the hot water from the hot water boiler during hot water use or consumption. Preferably, the apparatus further comprises in an embodiment or embodiments a flow switch and an external thermostat external to the hot water boiler located on the hot water consumption line for increasing the temperature of the hot water extracted during hot water consumption while maintaining a substantially low average temperature in the hot water boiler.

By use of the present invention, hot water from the upper portion of the hot water boiler is used for providing substantially immediately hot water for consumption. This permits the heating process to be more efficient since the water used for providing hot water is hot water located in the upper portion of the hot water boiler. This contributes to shorting the time of operation of the heating element thus reducing the amount of carbonate build-up and consequently maintaining the efficient operation of the heating element and prolonging the life of the heating element.

Furthermore, by locating, in accordance with the present invention, the thermostat in the inlet line of said heating element sleeve which supplies the water to heating element, accurate sensing of the heated water and the water to be heated is achieved. 218.s06 July 18, 2005 Thus, according to one embodiment of the present invention, apparatus is provided for producing hot water from a hot water boiler system comprising^ an inlet Une for supplying water from an upper portion of a hot water boiler to a heating element sleeve having a heating element so that the water is supplied to the heating element via a thermostat located in an inlet line of said heating element sleeve; a further hot water Une which connects a hot water Une outlet of the heating element sleeve to the upper portion of the hot water boiler wherein the height d fference between the lower end of either of said inlet Une or said further hot water Une in the upper portion of said hot water boiler and the top of said hot water boiler define a hot water volume maintained hot by said heating element and available for substantially immediate use or consumption; and a hot water consumption Une having an inlet in the upper portion of said hot water boiler for extracting the hot water from the hot water boiler during hot water use or consumption.

Furthermore, according to another embodiment of the present invention, apparatus is provided for producing hot water from a hot water boiler system comprising: an inlet line for supplying water from an upper portion of a hot water boiler to a heating element sleeve having a heating element so that the water is supplied to the heating element via a thermostat located in an inlet Une of said heating element sleeve! a further hot water line which connects a hot water line outlet of the heating element sleeve to the upper portion of the hot water boiler wherein the height difference .S u y , - 7 - between the lower end of either of said inlet line or said further hot water line in the upper portion of said hot water boiler and the top of said hot water boiler define a hot water volume maintained hot by said heating element and available for substantially immediate use or consumption," and a hot water consumption line is constructed and arranged such that it is located in said heating element sleeve and so that the inlet of said hot water consumption line is located close to and above the heating element.

Brief Description of the Drawings A description of the present inventive subject matter including embodiments thereof is presented and with reference to the accompanying drawings, the description is not meant to be considered limiting in any manner, wherein: Fig. 1 is a schematic arrangement of apparatus for producing hot water from a hot water boiler system in accordance with one embodiment of the invention,' Fig. 2 is a schematic arrangement of apparatus for producing hot water from a hot water boiler system in accordance with another embodiment of the invention; Fig. 3 is a schematic arrangement of apparatus for producing hot water from a hot water boiler system in accordance with a further embodiment of the invention! and .s u y , Fig. 4 is a schematic arrangement of apparatus for producing hot water from a hot water boiler system in accordance with an additional embodiment of the invention.

Similar reference numerals and symbols refer to similar components.

Detailed Description of Preferred Embodim n s The present invention comprises apparatus for producing hot water from a hot water boiler system. Fig. 1 shows a hot water boiler system in accordance with an embodiment of the present invention, designated by numeral 10 having hot water boiler 12 shown as a horizontal hot water boiler, heating element 14 and thermostat 16. Usually, such hot water boilers can contain about 80-300 liters of water. In addition, hot water boiler system 10 includes external thermostat 18 and flow switch 20 positioned on hot water outlet or discharge line 22 used for increasing or boosting the temperature of the hot water extracted during hot water consumption while maintaining a substantially low average temperature in hot water boiler 12. Hot water boiler system 10 furthermore includes heating element sleeve 24 containing heating element 14 and thermostat 16 and having pipe or line 26 and further hot water line 28 containing check valve 30, such as a floating ball check valve, etc., located preferably in the lowest portion of further hot water line 28 substantially adjacent heating element sleeve 24, for preventing water other than the water flowing across heating element 14 .s u y , - 9 - from being extracted via hot water outlet or discharge line 22 during hot water consumption. Preferably, check valve 30 including its body and ball are constructed of smooth plastic polymer material in order to diminish build up of carbonate sediments. In addition, the size of lines 26 and 28 as well as the size of check valve 30 is preferably chosen to be large enough, e.g. lines 26 and 28 having a diameter of about 25 mm or a cross-sectional area of about 500 mm2, in order to permit a substantially high thermo-syphon water flow rate at a limited pressure difference so that the temperature of water flowing through lines 26 and 28 is substantially low in order that build up of scale and carbonate sediments be small. In the present invention, preferably no constrictions are included in the lines 26 and 28. Fig. 1 shows a height difference between inlet 27 of line 26 and outlet 29 of further hot water line 28. The height difference between the lower end or outlet 29 of further hot water line 28 in the upper portion of the hot water boiler and the top of the hot water boiler is used for defining a certain volume, V, of water e.g. between about 25-50 liters, to be maintained at a hot water temperature for substantially immediate use by the consumer during hot water consumption and thus permits a smaller volume of water located in the upper portion of the hot water boiler 12 than the whole hot water boiler 12 to be maintained at the hot water temperature suitable for immediate use. In addition, in the present embodiment, inlet 21 of hot water consumption line or discharge 22 is preferably positioned at a position higher than heating element 14 in order to ensure effective heating of the volume of water traversing heating element .s u y , 14 from thermostat 16 to inlet 21 of hot water outlet or discharge 22 even during hot water consumption.

In operation, thermostat 16 controls the operation of heating element 14 in order to produce a volume of hot water in hot water boiler 12 between outlet 29 of further hot water hne 28 and the top of hot water boiler 12 to be maintained and available for substantially immediate use or consumption. Thus, when hot water is not consumed or extracted from hot water boiler 12, water flows into hne 26 via inlet 27 and thereafter into heating element sleeve 24 at its lowest portion via thermostat 16 positioned in the inlet line of heating element sleeve 24. The portion of inlet hne 26 which is part of heating element sleeve 24 is constructed and arranged such that the water flowing out of inlet line 26 flow across the length of heating element sleeve 24 and the volume of heating element 14 itself where it is heated by the heating element and the hot water thereafter exits the heating element sleeve via further hot water line 28 and check valve 30 through its outlet 29. In such a manner, a thermo-syphon flow pattern or cycle is produced across heating element sleeve 24 and within the upper portion of hot water boiler 12. When hot water is required by the consumer, flow switch 20 is activated, check valve 30 shuts and hot water commences to exit hot water boiler 12 via heating element sleeve 24 through hot water outlet or discharge line 22. Due to the fact that the inlet 21 of hot water discharge line 22 is positioned at a height higher than heating element 14, the water exiting hot water boiler 12 will be drawn across heating element 14 prior to exiting hot water boiler 12 .s u y , - 11 - and heating element sleeve 24 thus ensuring that such water is heated by heating element 14. If necessary, during hot water consumption, external thermostat 18 operates to operate heating element such that there is boosting of hot water heating and the water is thus heated to the required temperature.

Turning to the embodiment of the invention designated 10A as shown in Fig.2, a hot water boiler system is shown having hot water boiler 12A shown as a vertical hot water boiler, heating element 14A and thermostat 16A. Usually, such hot water boilers can contain about 80-300 liters of water. In addition, hot water boiler system 10A includes external thermostat 18A and flow switch 20A positioned on hot water outlet or discharge line 22A used for increasing or boosting the temperature of the hot water extracted during hot water consumption while maintaining a substantially low average temperature in hot water boiler 12A. Hot water boiler system 10A furthermore includes heating element sleeve 24A containing heating element 14A and thermostat 16A and having pipe or line 26A and further hot water line 28A containing check valve 30A, such as a floating ball check valve, etc., located preferably in the lowest portion of further hot water line 28A substantially adjacent heating element sleeve 24A, for preventing water other than the water flowing across heating element 14A from being extracted via hot water outlet or discharge line 22A during hot water consumption. Preferably, check valve 30A including its body and ball are constructed of smooth plastic polymer material in order to diminish build up .s u y , - 12 - of carbonate sediments. In addition, the size of lines 26A and 28A as well as the size of check valve 30A is preferably chosen to be large enough, e.g. lines 26A and 28A having a diameter of about 25 mm or a cross-sectional area of about 500 mm^, in order to permit a substantially high thermo-syphon water flow rate at a limited pressure difference so that the temperature of water flowing through lines 26A and 28A is substantially low in order that build up of scale and carbonate sediments be small. In the present invention, preferably no constrictions are included in the lines 26A and 28A. Fig. 2 shows a height difference between inlet 27A of line 26A and outlet 29A of further hot water line 28A. The height difference between the lower end or outlet 29A of further hot water line 28A in the upper portion of the hot water boiler and the top of the hot water boiler is used for defining a certain volume, V, of water e.g. between about 25-50 liters, to be maintained at a hot water temperature for substantially immediate use by the consumer during hot water consumption and thus permits a smaller volume of water located in the upper portion of the hot water boiler 12A than the whole hot water boiler 12A to be maintained at the hot water temperature suitable for immediate use. In addition, in the present embodiment, inlet 21A of hot water consumption line or discharge 22A is preferably positioned at a position higher than heating element 14A in order to ensure effective heating of the volume of water traversing heating element 14A from thermostat 16A positioned in the inlet line of heating element sleeve 24A to inlet 21A of hot water outlet or discharge 22A even during hot water consumption. .s u y , In operation, thermostat 16A controls the operation of heating element 14A in order to produce a volume of hot water in hot water boiler 12A between outlet 29A of further hot water line 28A and the top of hot water boiler 12A to be maintained and available for substantially immediate use or consumption. Basically, the operation of this embodiment is similar to the operation of the embodiment described with reference to Fig. 1. Thus, when hot water is not consumed or extracted from hot water boiler 12A, water flows into line 26A via inlet 27A and thereafter into heating element sleeve 24A at its lowest portion via thermostat 16A positioned in the inlet hne of heating element sleeve 24A. The portion of inlet line 26A which is part of heating element sleeve 24A is constructed and arranged such that the water flowing out of inlet line 26A flow across the length of heating element sleeve 24A and the volume of heating element 14A itself where it is heated by the heating element and the hot water thereafter exits the heating element sleeve via further hot water line 28A and check valve 30A through its outlet 29A. Thereafter, the water flows across the volume of heating element sleeve 24A where it is heated by heating element 14A and the hot water exits the heating element sleeve via further hot water line 28A and check valve 30A through its outlet 29A. In such a manner, a thermo-syphon flow pattern or cycle is produced across heating element sleeve 24A and within the upper portion of hot water boiler 12A. When hot water is consumed or required by the consumer, flow switch 20A is activated, check valve 30A shuts and hot water commences to exit hot water boiler 12A via heating element sleeve 24 .S u y , - 14 - through hot water outlet or discharge line 22A. Due to the fact that the inlet 21A of hot water discharge line 22A is positioned at a height higher than heating element 14A, the water exiting hot water boiler 12A will be drawn across heating element 14A prior to exiting hot water boiler 12A and heating element sleeve 24A thus ensuring that such water is heated by heating element 14A. If necessary, during hot water consumption, external thermostat 18A operates to operate heating element such that there is boosting of hot water heating and the water is thus heated to the required temperature.

As far as the embodiment of the invention shown as a vertical hot water boiler and designated 10B as shown in Fig.3, hot water boiler 12B includes heating element 14B and thermostat 16B. Usually, such hot water boilers can contain about 80-300 liters of water. Hot water boiler system 10B furthermore includes heating element sleeve 24B containing heating element 14B and thermostat 16B and having pipe or line 26B and further hot water line 28B. In addition, the size of lines 26B and 28B is preferably chosen to be large enough, e.g. lines 26B and 28B having a diameter of about 25 mm or a cross-sectional area of about 500 mm^, in order to permit a substantially high thermo-syphon water flow rate at a limited pressure difference so that the temperature of water flowing through lines 26B and 28B is substantially low in order that build up of scale and carbonate sediments be small. In the present invention, preferably no constrictions are included in the lines 26B and 28B. Fig. 3 shows a height difference between inlet 27B of line 26B and .S u y , - 15 - outlet 29B of further hot water line 28B. Preferably, the height, H, between the outlet 29B of further hot water line 28B and the top of hot water boiler 12B can be e.g. at least 7 cm. The height difference between the lower end or inlet 27B of hot water line 26B in the upper portion of the hot water boiler and the top of the hot water boiler is used for defining the volume, V, of water e.g. between about 25-50 liters, to be maintained at a hot temperature for substantially immediate use by the consumer during hot water consumption. In addition, in the present embodiment, inlet 21B of hot water consumption line or discharge 22B is preferably positioned at a position in the upper portion of hot water boiler 12B in order to extract hot water from the hot portion of hot water boiler 12B (during hot water consumption).

In operation, thermostat 16B controls the operation of heating element 14B in order to produce a volume of hot water in hot water boiler 12B between inlet 27B of line 26B and the top of hot water boiler 12B to be maintained and available for substantially immediate use or consumption. Thus, when hot water is not consumed or extracted from hot water boiler 12B, water flows into line 26B via inlet 27B and thereafter into heating element sleeve 24B at its lowest portion via thermostat 16B positioned in the inlet line of heating element sleeve 24B. The portion of inlet line 26B which is part of heating element sleeve 24B is constructed and arranged such that the water flowing out of inlet line 26B flow across the length of heating element sleeve 24B and the volume of heating element 14B itself where it is heated by the heating element and the hot water thereafter exits the heating .S u y , - 16 - element sleeve via further hot water line 28B through its outlet 29B. Thereafter, the water flows across the volume of heating element sleeve 24B where it is heated by heating element 14B and the hot water exits the heating element sleeve via further hot water line 28B through its outlet 29B. In such a manner, a thermo-syphon flow pattern or cycle is produced across heating element sleeve 24B and within the upper portion of hot water boiler 12B. When hot water is required by the consumer, hot water exits hot water boiler 12B via hot water consumption line or discharge line 22B.

Turning to the embodiment of the invention shown as a horizontal hot water boiler and designated IOC as shown in Fig.4, hot water boiler 12C includes heating element 14C and thermostat 16C. Usually, such hot water boilers can contain about 80-300 liters of water. Hot water boiler system IOC furthermore includes heating element sleeve 24C containing heating element 14C and thermostat 16C and having pipe or line 26C and further hot water line 28C. In addition, the size of lines 26C and 28C is preferably chosen to be large enough, e.g. lines 26C and 28C having a diameter of about 25 mm or a cross -sectional area of about 500 mm^, in order to permit a substantially high thermo-syphon water flow rate at a limited pressure difference so that the temperature of water flowing through lines 26C and 28C is substantially low in order that build up of scale and carbonate sediments be small. In the present invention, preferably no constrictions are included in the lines 26C and 28C. Fig. 4 shows a height difference between inlet 27C of line 26C and outlet 29C of further hot water line 28C. Preferably, the height, H, between .S u y , - 17 - the outlet 29C of further hot water line 28C and the top of hot water boiler 12C can be e.g. at least 7 cm. The height difference between the lower end or inlet 27C of hot water line 26C in the upper portion of the hot water boiler and the top of the hot water boiler is used for defining the volume, V, of water e.g. between about 25-50 liters, to be maintained at a hot temperature for substantially immediate use by the consumer during hot water consumption. In addition, in the present embodiment, inlet 21C of hot water consumption line or discharge 22C is preferably positioned at a position in the upper portion of hot water boiler 12C in order to extract hot water from the hot portion of hot water boiler 12C (during hot water consumption).

In operation, thermostat 16C controls the operation of heating element 14C in order to produce a volume of hot water in hot water boiler 12C between inlet 27C of line 26C and and the top of hot water boiler 12C to be maintained and available for substantially immediate use or consumption. Basically, the operation of this embodiment is similar to the operation of the embodiment described with reference to Fig. 3. Thus, when hot water is not consumed or extracted from hot water boiler 12C, water flows into line 26C via inlet 27C and thereafter into heating element sleeve 24C at its lowest portion via thermostat 16C positioned in the inlet line of heating element sleeve 24C. The portion of inlet line 26C which is part of heating element sleeve 24C is constructed and arranged such that the water flowing out of inlet line 26C flow across the length of heating element sleeve 24C and the volume of heating element 14C itself where it is heated by the heating .S06 Ju y 1 , - 18 - element and the hot water thereafter exits the heating element sleeve via further hot water hne 28C through its outlet 29C. Thereafter, the water flows across the volume of heating element sleeve 24C where it is heated by heating element 14C and the hot water exits the heating element sleeve via further hot water line 28C through its outlet 29C. In such a manner, a thermo-syphon flow pattern or cycle is produced across heating element sleeve 24C and within the upper portion of hot water boiler 12C. When hot water is required by the consumer, hot water exits hot water boiler 12C via hot water consumption line or discharge hne 22C.

While outlets 29 and 29A of further hot water lines 28 and 28A respectively are shown in Figs. 1 and 2 are straight-edged, if preferred a deflector can be added to this outlet in each of the embodiments described with reference to Figs. 1 and 2 so that hot water exiting these outlets will mix effectively with other water present in hot water boilers 12 and 12A respectively. Such a deflector designated 32 and 32A respectively are shown in Figs. 1 and 2.

Furthermore, optionally, if preferred, a heating element comprising of two sections can be used instead of heating elements 14 and 14A respectively. One section operates and is controlled by internal thermostat 16 and 16A respectively, while both of the sections operate during water consumption.

Thus, in accordance with the present invention, the height difference between the end or outlet 29 or 29A of further hot water hne 28 or 28A and 1 .s0 Ju y , - 19 - the top of the hot water boiler, respectively shown in Figs. 1 and 2, or the height difference between the lower end or inlet 27B of hot water line 26B and the top of the hot water boiler shown in Fig. 3 defines a defined volume of hot water, substantially less than the total volume of hot water boilers 12, 12A, 12B and 12C, that is available for substantially immediate use or consumption. Thus, by designing these ends or outlet 29 or 29A of further hot water line 28 or 28A or inlet 27B, 27C of hot water line 26B, 26C to produce a height difference between each of these ends and the top of the hot water boiler, a hot water volume suitable for substantially immediate use or consumption can be provided for e.g. a one person, two person, three person, four person, family, etc..

In addition, it should be pointed out that while inlet 21 or 21A of hot water outlet or discharge line 22 or 22A is preferably positioned in the close vicinity of further hot water line 28, 28A near check valve 30 or 30A respectively, and above or at a height higher than heating element 14 or 14A respectively, inlet 21 or 21A, can be positioned at a location anywhere along the length of heating element 14 or 14A respectively. By using the preferred location in the close vicinity of further hot water line 28, 28A near check valve 30 or 30A respectively, a higher level of thermal efficiency for heating the water with heating element 14 or 14A respectively is achieved as well as permitting simplifying its manufacture. Furthermore, this permits the substantially sole use of water heated by heating element 14 or 14A, .S u y , - 20 - respectively, as the hot water supplied via hot water outlet or discharge line 22 or 22A for consumption.

Furthermore, inlet 27, 27A of inlet line 26 or 26A are located near the top of hot water boiler 12 or 12A respectively in order to facilitate extraction of air from the hot water boiler system.

In addition, heating element sleeves, 24, 24A, 24B and 24C are constructed preferably from plastic which can operate up to 95°C.

Moreover, the present invention will permit the lowering the temperature set by thermostat 16, 16A, 16B and 16C. In accordance with the prior art, usually such a setting was made at 60°C.

It is to be emphasized the size of the inlet hot water lines and further hot water lines are preferably chosen to be substantially large in order to reduce the formation and deposition of carbonate in the apparatus described herein and in particular in the further hot water line.

In addition, by using the method and apparatus of the present invention, the amount of time needed for the heating element to reach the desired temperature is small compared to the amount of time apparatuses of the prior art need thus also ensuring that the carbonate production and deposition when using the methods and apparatus of the present invention will be substantially reduced.

Furthermore, by use of the present invention, hot water from the upper portion of the hot water boiler is used for providing substantially immediately hot water for consumption.

.S u y , Moreover, by locating, in accordance with the present invention, thermostat 16, 16A, 16B and 16C in the inlet line of said heating element sleeve which supplies the water to the heating element, accurate sensing of the water to be heated is achieved. Preferably, the portion of line or inlet line 26, 26A, 26B and 26C where thermostat 16, 16A, 16B and 16C is located is spaced from heating element 14, 14A, 14B and 14C in heating element sleeve 24, 24A, 24B and 24C in order to reduce loss of heat to incoming water supplied to heating element sleeve 24, 24A, 24B and 24C via thermostat 16, 16A, 16B and 16C located in hot water line 26, 26A, 26B and 26C respectively.

These measures contribute to shorting the time of operation of the heating element thus reducing the amount of carbonate build-up and consequently maintaining the efficient operation of the heating element and prolonging its operating life. Thus, the operation of a hot water boiler system in accordance with the present invention will also bring about a savings in energy consumed.

While the above description refers to a horizontal and vertical hot water tanks and suitable apparatus, the apparatus used for the horizontal hot water tank can, if preferred, be used in a vertical hot water tank Furthermore, while the above description refers to a hot water boiler system and embodiments thereof, specifically, the hot water boiler system can be a solar hot water boiler system wherein solar energy or radiation can .s u y , - 22 - be used to provide hot water in addition to the heating elements 14, 14A, 14B and 14C described above using e.g. a solar hot water collector.

Furthermore, the present invention can be used as a retrofit kit to retrofit an existing boiler. In other words, the flange containing the heating element sleeve together with the thermostat, heating element and hot water discharge can used to replace the existing flange of an existing boiler.

Auxiliary equipment (e.g. values, controls, etc.) are not shown in the figures for sake of simplicity.

While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried into practice with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without departing from the spirit of the invention or exceeding the scope of the claims. 169779/03 218.S06 July 18, 2005

Claims (37)

1. A method for producing hot water from a hot water boiler system comprising the steps of (a) supplying water via an inlet line from an upper portion of a hot water boiler to a heating element sleeve having a heating element so that the water is supplied to the heating element via a thermostat located in an inlet line of said heating element sleeve! (b) providing a further hot water line which connects a hot water line outlet of said heating element sleeve to the upper portion of the hot water boiler wherein the height difference between the lower end of either of said inlet line or said further hot water line in the upper portion of said hot water boiler and the top of said hot water boiler define a hot water volume maintained hot by said heating element and available for substantially immediate use or consumption; and (c) providing a hot water consumption line for extracting the hot water from the hot water boiler for hot water use or consumption.

2. The method according to claim 1 further comprising the step of using a flow switch and an external thermostat external to the hot water boiler located on the hot water consumption line for increasing the temperature of the hot water extracted during hot water consumption while maintaining a substantially low average temperature in the hot water boiler.

3. The method according to claim 1 further comprising the step of providing a check valve located in the further hot water line for preventing 169779/02 218.S06 July 18, 2005 - 24 - water other than the water flowing across the heating element from being extracted via hot water discharge or consumption line during hot water consumption.

4. The method according to claim 1 further comprising locating said hot water consumption line within said heating element sleeve so that the inlet of said hot water consumption line is located close to and above the heating element.

5. The method according to claim 3 further comprising locating said hot water consumption line within said heating element sleeve so that the inlet of said hot water consumption line is located close to and above the heating element and also adjacent said check valve.

6. The method according to claim 1 further comprising locating said hot water consumption line in the upper portion of said hot water boiler.

7. The method according to claim 1 wherein the end of said inlet line located in the upper portion of said hot water boiler is higher than the end of said further hot water line.

8. The method for producing hot water according to claim 3 wherein said check valve comprises a floating ball check valve.

9. The method for producing hot water according to claim 1 wherein said hot water system comprises a solar hot water system.

10. The method for producing hot water according to claim 3 wherein said check valve is located in the close vicinity to said heating element sleeve. 169779/02 218.s06 July 18, 2005 - 25 -

11. The method according to claim 1 wherein the end of said inlet line located in the upper portion of said hot water boiler is lower than the end of said further hot water line.

12. The method according to claim 1 wherein the step of providing a hot water consumption line for extracting the hot water from the hot water boiler is carried out by providing a hot water consumption line for extracting the hot water from the hot water boiler the end of which is located in the upper portion of said hot water boiler external to said heating element sleeve.

13. The method for producing hot water according to claim 1 wherein the diameter of said inlet line and said further line is selected so that a flow rate of water is permitted which ensures that build up of scale and carbonate sediments is small.

14. The method for producing hot water according to claim 1 wherein the size of the check valve is selected so that a flow rate of water is permitted which ensures that build up of scale and carbonate sediments is small.

15. The method for producing hot water according to claim 1 wherein said thermostat is positioned so that the water supplied from the top of the hot water boiler is supplied first to the thermostat and thereafter to the heating element. 169779/03 218.S06 July 18, 2005 - 26 -

16. Apparatus for producing hot water from a hot water boiler system comprising: (a) an inlet line for supplying water from an upper portion of a hot water boiler to a heating element sleeve having a heating element so that the water is supplied to the heating element via a thermostat located in an inlet line of said heating element sleeve; (b) a further hot water line which connects a hot water line outlet of the heating element sleeve to the upper portion of the hot water boiler wherein the height difference between the lower end of either of said inlet line or said further hot water hne in the upper portion of said hot water boiler and the top of said hot water boiler define a hot water volume maintained hot by said heating element and available for substantially immediate use or consumption; and (c) a hot water consumption line for extracting the hot water from the hot water boiler during hot water use or consumption.

17. Apparatus according to claim 16 further comprising a flow switch and an external thermostat external to the hot water boiler located on the hot water consumption line for increasing the temperature of the hot water extracted during hot water consumption while maintaining a substantially low average temperature in the hot water boiler.

18. Apparatus according to claim 16 further comprising a check valve located in the further hot water line for preventing water other than the 169779/02 218.s06 July 18, 2005 - 27 - water flowing across the heating element from being extracted via hot water discharge or consumption line during hot water consumption.

19. Apparatus according to claim 16 wherein said hot water consumption line is constructed and arranged such that it is located in said heating element sleeve and so that the inlet of said hot water consumption line is located close to and above the heating element.

20. Apparatus according to claim 18 wherein said hot water consumption line is constructed and arranged such that it is located in said heating element sleeve and so that the inlet of said hot water consumption line is located close to and above the heating element, and also adjacent said check valve.

21. Apparatus according to claim 16 wherein said hot water consumption line is constructed and arranged such that it is located in the upper portion of said hot water boiler.

22. Apparatus for producing hot water according to claim 18 wherein said check valve comprises a floating ball check valve.

23. Apparatus for producing hot water according to claim 18 wherein said floating ball check valve is constructed and arranged to diminish build up of scale and carbonate sediments.

24. Apparatus for producing hot water according to claim 18 wherein said floating ball check valve is constructed from smooth plastic polymer which diminishes build up of scale and carbonate sediments. 169779/02 218.S06 July 18, 2005 - 28 -

25. Apparatus for producing hot water according to claim 16 wherein said hot water system comprises a solar hot water system.

26. Apparatus for producing hot water according to claim 18 wherein said check valve is located in the close vicinity to said heating element sleeve.

27. Apparatus for producing hot water according to claim 16 wherein the diameter of said lines is selected so that a flow rate of water is permitted which ensures that build up of scale and carbonate sediments is small.

28. Apparatus for producing hot water according to claim 16 wherein the size of the check valve is selected so that a flow rate of water is permitted which ensures that build up of scale and carbonate sediments is small.

29. Apparatus for producing hot water according to claim 16 wherein said thermostat is positioned so that the water supplied from the top of the hot water boiler is supplied first to the thermostat and thereafter to the heating element.

30. Apparatus according to claim 29 wherein the portion of said line or inlet line where thermostat is located is spaced from heating element in heating element sleeve in order to reduce loss of heat to incoming water supplied to heating element sleeve via thermostat located in said hot water line.

31. Apparatus according to claim 16 further comprising a deflector connected to further hot water line near its outlet so that water exiting said 169779/03 218.S06 July 18, 2005 - 29 - further hot water line will mix with water present in the upper portion of said hot water boiler.

32. Apparatus for producing hot water from a hot water boiler system comprising: (a) an inlet line for supplying water from an upper portion of a hot water boiler to a heating element sleeve having a heating element so that the water is supplied to the heating element via a thermostat located in an inlet line of said heating element sleeve; (b) a further hot water line which connects a hot water line outlet of the heating element sleeve to the upper portion of the hot water boiler wherein the height difference between the lower end of either of said inlet line or said further hot water line in the upper portion of said hot water boiler and the top of said hot water boiler define a hot water volume maintained hot by said heating element and available for substantially immediate use or consumption; and (c) a hot water consumption line having an inlet in the upper portion of said hot water boiler for extracting the hot water from the hot water boiler during hot water use or consumption.

33. Apparatus for producing hot water from a hot water boiler system comprising: (a) an inlet line for supplying water from an upper portion of a hot water boiler to a heating element sleeve having a heating element so that the 169779/03 218.s06 July 18, 2005 - 30 - water is supplied to the heating element via a thermostat located in an inlet line of said heating element sleeve? (b) a further hot water line which connects a hot water line outlet of the heating element sleeve to the upper portion of the hot water boiler wherein the height difference between the lower end of either of said inlet line or said further hot water line in the upper portion of said hot water boiler and the top of said hot water boiler define a hot water volume maintained hot by said heating element and available for substantially immediate use or consumption; and (c) a hot water consumption line is constructed and arranged such that it is located in said heating element sleeve and so that the inlet of said hot water consumption line is located close to and above the heating element.

34. A method for producing hot water from a hot water boiler system according to claim 1 substantially as hereinbefore described and with reference to the accompanying drawings.

35. Apparatus for producing hot water from a hot water boiler system according to claim 16 substantially as hereinbefore described and with reference to the accompanying drawings.

36. Apparatus for producing hot water from a hot water boiler system according to claim 32 substantially as hereinbefore described and with reference to the accompanying drawings. 218.S06 July 18, 2005 - 31 -

37. Apparatus for producing hot water from a hot water boiler system according to claim 33 substantially as hereinbefore described and with reference to the accompanying drawings. ACTiyEHOME LTD. ,9 \*Y ,