DE2729668A1 - WATER HEATING SYSTEM - Google Patents

Description

Patent attorneys:

A. GRUNEeCKCR K. SCHUMANN vm \ IW. m η H. KINKELDEY ρ. H. JAKOB OH-* G. BEZOLD W. STOCKMAIR UtNAT ΙΡΙΛ (JtM

8 MUNICH 22

MAXIMILIAMSTRASSE 43

7.Γ. , τ ·> -, -.! ΊΓ17 · ";

Water heating system

This invention relates to a system for heating water and, more particularly, to a novel combined one Storage tank and heat exchanger unit for use in the system.

A prior art search directed to the subject matter of this application was found the following US PSs:

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1 786 861 2 562 651

1,830 195 2,632 306

1 967 136 2 668 420

2 007 426 2 716 866 2 095 017 2 751 761 2 310 234 3 472 314 2 355 551 3 507 324 2 412 774 3 578 074 2 516 094 3 807 192 2 561 465 3 934 821

None of the publications of the research found Prior art discloses a plant such as that of the present invention which operates to supply heated water to generate two useful and clearly different temperatures. This is done in that one uses the hot refrigerant from a refrigeration compressor operating at pressures and temperatures within "the optimal range of efficiency and durability can be operated for the unit.

In summary, the invention relates to a combined storage tank and heat exchanger unit for heating and storing water, which unit has a liquid-tight tank which has a liquid inlet device and a liquid outlet device. The tank further includes a jacket or double wall that defines at least a portion of the outer wall of the tank. The double wall has an inlet and an outlet and channel means which extend within the double wall from the inlet to the outlet and through which a hot fluid can be passed to heat the liquid on the inside of the tank. A thermal barrier device is inside the tank as well as at a small distance from the

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inner surface of the double wall attached to a relatively Thermally isolate small volume of liquid that is in direct contact with the inner The surface of the double wall is around this small volume at a relatively rapid rate to heat up.

A special idea of the invention lies in a combined storage tank and heat exchanger unit for heating of water, with a waterproof tank that has a water inlet in its lower section and a pair Has water outlets in its upper portion. The wall of the tank is in the form of a double-walled jacket formed having an inlet for hot coolant at its upper portion and an outlet for hot coolant having at their bottom portion. A cylindrical thermal barrier is installed on the inside of the tank and arranged at a small distance from the inner surface of the double wall, by a relatively To thermally isolate a small amount of water in the tank that is in contact with the inner surface of the double wall. A thermal barrier disc is mounted in the tank and extends horizontally across its interior to the water thermally isolate the upper portion of the tank from the water in its lower portion. The water outlets communicate with the interior of the tank on opposite sides of the partition to provide heated water to be provided under two clearly different temperatures. An air channel is between the outer surface of the double jacket and the inner surface of the outer shell through which air is passed to to heat the room within which the unit is located.

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The subject matter of the invention is explained in greater detail, for example, with reference to the accompanying drawing. Show it:

Fig. 1 is a partially schematic view of the invention Water heating system,

FIG. 2 is a side view (with parts broken away) of the heat exchanger unit of that shown in FIG Water heating system,

Fig. 3 is a view of a vertical section of the heat exchanger unit shown in Fig. 2, wherein the outer jacket and insulation have been removed,

Fig. 4 is a view of a section along the line 4-4 in Fig. 2 was made,

Fig. 5 is a view of a section taken along line 5-5 in Fig. 2;

FIG. 6 is a side view (with parts broken away) of a second exemplary embodiment of the one shown in FIG. 2 to 5 shown heat exchanger unit,

Fig. 7 is a view of a section taken along line 7-7 in Fig. 6;

8 is a fragmentary sectional view taken along line 8-8 in FIG became.

The description of the preferred embodiments now follows. While the present invention has several useful May have areas of use, it was especially designed for use by dairy farmers Peasants are designed, and for the purpose of illustration the following description is based on a typical installation directed at a dairy farm.

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Reference is now made to the schematic view of the plant as shown in Figure 1; the plant includes a heat exchanger unit 10, a pair of compressors 12, a collecting cooler 14 and a water storage and / or heater unit 16, the last unit only being provided as an option.

The heat exchanger unit 10 has an outer double wall 18 with upper and lower headers 20 and 22 attached thereto to form a watertight tank 23. The double wall 18 can be of any suitable construction that provides a sealed cylindrical conduit through which fluid can be circulated from one end to the other. In the embodiment shown in the drawings (Figs. 2, 3 and 4), the double wall 18 is designed in the form of two metal sheets which are welded together, with fluid channels being formed between them to form a fluid-conveying heat transfer part. Examples of suitable double wall constructions are described in detail in U.S. Patent 3,458,917.

The double wall 18 is provided with a pair of inlet ports 24 and a pair of outlet ports 26. In the preferred embodiment, the double wall 18 and the headers 20, 22 are made from stainless steel.

On the inside of the waterproof tank 23, which is formed by the double jacket 18, the head 20 and the head 22, two cylindrical heat barrier members 28 and 30 are attached. The parts 28 and 30 have the same diameter and are concentrically mounted. A disk-shaped heat barrier member 32 is attached between the parts 28 and 30. In the preferred embodiment, parts 2B, 30 and 32 are made from fiberglass material. It is noted at this point that the parts 28 and 30 are dimensioned such that

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that their outer surfaces have a relatively small distance from the inner surface of the double jacket 18 in order to provide a relatively narrow cylindrical channel 34 which extends from one end of the tank 23 to the other. The disc 32 is provided with several openings 33 (FIG. 5) in order to allow the free circulation of water from one side of the disc to the other. The heat barrier part 28 is provided with several openings 29 around its upper edge or along its upper edge, and the heat barrier part 30 is provided with several openings 31 around its lower edge or along its lower edge.

The tank 23 is provided with a cold water _{inlet 36 and hot and hot water outlets 38 and} 40. The outlet extends through the heat barrier part 28 to communicate directly with the water on the inside of the part 28.

As shown in Fig. 2, the heat exchanger unit is provided with an outer layer 42 of insulating material and a outer jacket 44 is provided which encloses the insulating layer. For control reasons, as detailed below As illustrated, there is a pair of pressure sensitive flow regulating water valves 46, 48 on the hot water outlet 38 attached. The valves 46, 48 are connected to pressure sensing coupling assemblies 50, 52 by means of pipes 45, 56 are attached to the inlets 24 for hot coolant.

Hot refrigerant gas (preferably Frigen) is fed from the compressors 12 via lines 58, 60 to the inlets 24 of the double wall 18. Condensed coolant is conducted from the double-walled outlets 26 to the collective cooler 14 by means of lines 62, 64. Evaporated refrigerant is from the

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Samnie! Cooler 14 by means of lines 66, 68 to the compressor ren 12 returned.

In the water section of the system, heated water is supplied by the outlets 38 and 40 for heated water through supply lines 70, 72 discharged. As indicated above, a water heater or storage tank 16 may be dependent to be provided by the specific needs of the farm / in which the system is installed.

Reference is now made to the further exemplary embodiment of the heat exchanger unit, which is shown in FIGS. 6, 7 and 8 is shown, such a unit being similar to that shown in Figures 2-5 and being correspondingly similar or the same parts of the corresponding units have been given the same reference numerals.

The heat exchanger unit 74, which is shown in FIGS. 6 to 8, has a double wall 18, which together with End cap parts forms a watertight tank identical to the tank 23 shown in FIG.

The double jacket 18 is provided with a pair of inlet connections 24 and a pair of outlet connections 26. Inside the waterproof tank, a pair of cylindrical heat barrier members 28 and 30 and a disk-shaped heat barrier member 32 that is mounted between the parts 28 and 30 are mounted. The specific shape and mounting arrangement of the thermal barrier members is shown in FIG. As in the unit 10, as shown in FIG. 3, there is a narrow cylindrical channel 34 which extends from one end of the tank to the other in the unit 74.

The watertight tank is provided with a cold water inlet 36 and a hot water outlet 38 and 40, respectively.

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A pair of pressure sensitive flow regulating water valves are provided for control purposes Ie 46, 48 arn hot water outlet 38 appropriate. The valves 46, 48 are connected to pressure sensing coupling assemblies 50, 52 by means of pipes 54, 56 are attached to the inlets 24 for hot coolant.

Up to this point in the specification, the structure of the heat exchanger unit 74 (Figs. 6-8) has been identical to that the heat exchanger unit 10 (Figs. 2 to 5). The principal difference between the two units lies in that in the unit 74 an air duct 76 between the outer surface of the double jacket part 18 and the inner surface of the outer shell 78 is provided. More precisely, such a channel is provided in that Insulating material 80 between the jackets 18 and 78 only below an air inlet 82 and above an air outlet 84 is mounted so as to provide a flow channel 76 between such inlet and outlet. To more effectively direct the flow of air from inlet 82 to outlet 84 from the standpoint of optimizing heat transfer Seen between the jacket 18 and air, there is a barrier 86 of insulating material between the inlet and the outlet 84 is provided. The barrier 86 surrounds the jacket portion 18 of the watertight tank 24 between the Inlet 82 and outlet 84 in part so as to cause the air to flow through channel 76, to flow in a detour as shown by the arrows in FIG.

A pressure blower unit 88 of any suitable construction may be attached to the air inlet 82 to circulate air forced to flow from the inlet through the channel 76 to the outlet 84. The fan unit 88 is with a thermostat-controlled ON-OFF switch 92 is provided, which at a predetermined lower and upper ambient temperature

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door causes the fan to be switched on and off. As in 6 and 7, a corrugated filler 90 of fiberglass or other suitable material is incorporated Air duct space 76 mounted opposite the insulating barrier 86 to provide structural support between the outer jacket 78 and the inner jacket 18 without significantly affecting the To restrict air flow. The insulating barrier and the filling part 90 are attached to the jacket 18 by means of a belt or bracket 94 held in place.

The operation of the plant can best be described with reference to FIG. While the plant of the present invention can operate under a variety of specific operating conditions will only a typical operational installation is described below.

In a typical milking cycle, there is initially a need for heated water for the purpose of the first cows in the herd to prepare for milking and to clean the pipelines of the milking facility. In the facility of the present invention such water would normally be obtained from the heat exchanger unit 10 which is some heated Still contains water left over from the previous milking cycle.

When milking of the herd begins, warm milk is introduced into the bulk cooler 14. When the milk in the cooler reaches a predetermined, thermostatically controlled or regulated lower or upper temperature, the cooling system is put into operation. After the compressors 12 have been started up, hot refrigerant gas will flow from them through the lines 58, 60 to the inlets of the double wall 18. As the hot Frigen coolant passes down through the jacket 18, it will give off heat to the water in the tank 23 which does the

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Frigen gas causes it to condense.

The condensed Frigen flows through lines 62, 64 to the collector cooler 14, where it passes through a suitable evaporator device (not shown) is passed through to achieve the desired cooling effect on the collective cooler in one conventional way to provide. The relatively cool refrigerant gas flows from the collector cooler through lines 66, 68 back to compressors 12.

Turning now to the water circulation section of the system, the typical installation would be this is described, the tank 2 3 is dimensioned such that it has about 409 liters or 341 liters of water below the disk lock 32 and about 227 liters or 189 liters of water above the disk 32. Cold water to be heated enters the heat exchanger unit 10 through inlet 36 in the lower portion thereof. As from the arrows in As shown in Fig. 1, the water in the tank 23 will circulate upwards in the relatively narrow cylindrical channel 34, formed between the inner surface of the double wall 18 and the outer surface of the thermal barrier cylinders 28, 30 is. It should be noted at this point that the Thermal barrier device, which is provided by the parts 28 and 30, serves a relatively small Water volume that is in direct contact with the hot inner surface of the jacket 18 is thermally entitled isolate. The result is that such an isolated volume of water can be achieved in a relatively rapid manner Speed is heated (compared to the water in the rest of the tank) which results in such water increases relatively rapidly in channel 34.

As the water circulates upward in channel 34, its temperature gradually increases. When the water in the canal 34 reaches the thermal barrier disk 32 then becomes a part

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from this into the interior of the tank through openings 29 and 31 circulate in, and some of this will continue to flow up in channel 34 to the top of the tank, this latter part being heated to a higher temperature.

Within a matter of minutes after the compressors 12 have started, water becomes medium Temperature are available at the hot water outlet 38 of the unit 10 in order to additionally prepare cows for milking. Such hot water will be used more or less continuously throughout the milking cycle for the entire milking cycle Preparing herd for milking.

During the milking cycle, the duration of which ranges anywhere from about an hour to two and a half hours, in Depending on the size of the flock, the water will be in the heated upper portion of the tank 23 above the disk 32 to a relatively high temperature, and accordingly At the end of the milking cycle, 227 or 189 liters of hot water are available to the farmer to wash the milking system Disposal.

Meanwhile, it is emphasized that the specific temperatures and pressures of the typical installation described here vary a little during the milking cycle, but when such a typical installation is a more general condition When equilibrium is reached, the following temperatures and pressures will prevail.

The hot refrigerant gas from the compressors 12 entering the jacket 18 through the inlets 28 will be at a temperature of about 377 ° K and a pressure of about 19.3 kg / cm *. The condensed refrigerant leaving the double wall 18 through the outlets 26 is at a temperature of about 316 ° K and a pressure of about 19 kg / cm ²

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lie. At such temperatures and pressures of the heat Frigen water arn for preparing the cows for milking 38- outlet is available, for instance have a temperature of 316 ⁰ K, assuming a cold water supply temperature of about 291 ⁰ K.

As indicated above, the continuous operation of the plant will be the temperature in the upper section of the tank 23 cause it to heat up to a relatively higher temperature. The temperatures in the upper tank section are shown in the table below:

Number and design (in kW) of the compressors

2.238

2,984

3.73

2,238

2,984

3.73

Time (in hours) 2 1/2 11/2 2 344 333 * 339 347 336 341 350 339 344 352 341 347 358 347 352 361 352 358

* MEASURED IN ° K

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The operating conditions described above are maintained by a water flow regulator which provides pressure sensitive water regulating valves 46,48 at the hot water outlet 38. As stated above, the valves 46, 48 are connected by pipes 54, 56 to the outdoor inlet pressure connections or pressure coupling devices 50, 52. The components are set so that when the coolant pressure at the coupling devices 50, 52, 19.3 kg / cm ² (which corresponds to a condensation temperature of about 327 ° K) then open the corresponding valves 46, 48 and let warm water out of the unit 10 through the outlet 38. If there is no need for warm water at this time, then warm water can simply flow to a storage tank or a drain.

It is apparent from the above description that such a control arrangement automatically the Controls or regulates the maximum temperature and the maximum pressure of the compressors 12 at the outlet for hot coolant, and at the same time providing hot water for the farmer at two separate and desirable temperatures. The unit "Achieves this goal without excessively high pressure from the fringes to be used at the compressor outlet in order to maintain the efficiency of the compressors and their service life to increase to a maximum. Thus, the cooling system and in particular the compressors can operate under operating conditions be operated that are effective and ensure maximum service life to generate the warm water, that is required of the farmer during a normal milking cycle. This comes with components and controls achieved relatively simple and economical construction.

The operation of the heat exchange unit 74 is quite similar to that of the unit 10 described above.

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The hot water and cooling sections of the overall system using unit 74 are essentially the same as the sections described above with reference to the unit.

The unit 74 provides an additional function, namely the heating of the ambient air at the location, on which the unit is installed. This is accomplished by having an air duct 76 inside the outer Sheath 78 is provided. If the ambient temperature of the unit is a predetermined minimum during operation reached (for example 4.5 ° C or 277.5 ° K), then the thermostatic control 92 will turn on the fan 88 and causing cold air from outside the unit to be forced into duct 76 through the air inlet 82 is initiated. As shown by the arrows in Figure 6, air travels upward from inlet 82 and around the ends isolation barrier 86 and then out through outlet 84. When the air passes over the exposed, heated outer surface of the inner jacket 18 flows, then it is heated so that the air released into the surrounding area through the outlet 84 flows out is at a higher temperature than the air entering the unit through inlet 88.

The unit thus not only serves to heat water for use by the farmer, but also serves to heat the enclosed area in which the unit is installed. The heat needed to heat the Air availability, as described above, will primarily depend on the amount of warm water that is used Farmers, as well as the size and number of compressors used in the system. Experience has shown that in most installations there is excess heat available to heat the ambient air as well as the water required for milking, and thus a unit 74 as described above can

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and shown in Figures 6, 7 and 8 can be advantageously used in many ways. In this regard, it should be emphasized that the air heating property of the unit 74 can be incorporated into the unit at very little overhead beyond the cost required to construct the unit 10. This results in that the air-warming unit 74 can serve to make a maximum use of the energy in the hot Frigengas that is available in a conventional cooling system, which is normally used by an agricultural dairy farm, in order to cool the milk produced by the cows will.

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Claims (23)

PATENT ADVOCATES A. GRÜNECKER LXPL IWj H. KINKELDEY mi ing W. STOCKMAIR OH ΙΝΠ A ₁ F (TAIlIrM: K. SCHUMANN GRHUtNAi ΙΛΙ \ flfvS P. H. JAKOB D (Pl-WIG G. BEZOLD DR «/ I MAT I] (PL Ο% Λ1 8 MUNICH MAXIMILIANSTRASSE Expectations M .J Combined storage tank and heat exchanger unit for heating and storing a liquid such as water or the like, characterized by - A liquid-tight tank device (23) with a liquid inlet device (36) and a liquid outlet device (38, 40), and furthermore with a double wall device (18), the at least one section the outer wall of the liquid-tight tank device and an inlet device (24) as well an outlet means (26) and a channel means which is located within the double wall means extending from the inlet means to the outlet means and facing the inside of the liquid-tight Tank device is sealed, and -. a thermal barrier device (38, 30) which is mounted inside the liquid-tight tank device and is arranged at a small distance from the inner surface of the double-walled device in order to thermally isolate a relatively small volume of liquid which is in direct contact with the inner surface in the liquid-tight tank device the double wall device is. 809817/0600 - 2 - TElFFON (OOO) 33 2β β3 TELEX OC-9O.1CO TELeQHAMMi-: MONAPAT ORIGINAL INSPECTED 2. Unit according to claim 1, characterized in that the heat lock device further comprises a heat lock subdivision (32) which extends substantially transversely to the interior of the liquid-tight tank device (23) extends and serves to keep the liquid in the upper Section of the liquid-tight tank device from the To thermally insulate liquid in the lower section, and that the liquid outlet device for the liquid-tight tank means comprises a pair of liquid outlets (38, 40) connected to the opposite Sides of the thermal barrier subdivision are arranged. 3. Combined storage tank and heat exchanger unit for heating and storing a liquid such as Water or the like, characterized by a liquid-tight tank device (23) with a Liquid inlet means (36) in its lower portion and a liquid outlet means (38, 40) in its upper section, and also with a vertically arranged, cylindrical double-wall device (18) which forms at least a portion of the outer wall of the liquid-tight tank device and a Inlet means (24) in its upper portion and outlet means (26) in its lower portion and channel means extending within the double wall means from the inlet to the outlet means extends and is sealed against the inside of the liquid-tight tank device, and a thermal barrier device which is attached to the inside of the liquid-tight tank device and a cylindrical heat barrier member (28, 30) facing the inner cylindrical surface of the Double-wall device has a small distance to a relatively small volume of liquid, in the liquid-tight tank facility in the immediate 809817/0600 _ ₃ _ direct contact with the inner surface of the double wall device stands to insulate thermally. 4. Unit according to claim 3, characterized in that the thermal barrier device is further in the form of a disk Has thermal barrier subdivision (32) which extends substantially transversely to the interior of the liquid-tight tank device (23) extends in the upper section and serves to keep the liquid in the upper section of the liquid-tight To thermally isolate the tank device from the liquid in its lower portion, and that the liquid outlet device for the liquid-tight steering device a pair of liquid outlets (38, 40) arranged on opposite sides of the thermal barrier subdivision. 5. Unit according to claim 4, characterized in that the cylindrical heat barrier part (28, 30) several Has through openings (29) around its circumference immediately below the thermal barrier subdivision (32). 6. Unit according to claim 5, characterized in that the heat barrier subdivision (32) has a plurality of through openings (33). 7. Unit according to claim 6, characterized in that the heat barrier part (28, 30) has a plurality of through openings (31) around its circumference immediately above the thermal barrier subdivision (32). 8. Unit according to claim 3, characterized in that the double wall device (18) has the shape of a Has a pair or two metal plates which are welded together with fluid channels in between to to form a fluid-conveying heat transfer member. 809817/0600 9. Water heating systems, characterized by a source (12) of hot fluid, a combined storage tank and heat exchanger unit (10, 74) with a watertight tank device (23) which has a water inlet device (36) in its lower portion and a water outlet means (38, 40) in its upper portion and further a cylindrical double wall device (18) comprising at least a portion of the outer wall of the forms watertight tank means and has inlet means (24) in its upper portion, in communication with the source of hot fluid and an outlet device (26) in it has lower portion and a channel device, which extends within the double wall device of the Inlet to outlet means extends through which hot fluid can flow and the opposite the inside of the waterproof tank device is sealed, which also has a heat barrier device has, which is mounted on the inside of the waterproof tank device and a cylindrical Has heat barrier part (28, 30), which is at a small distance from the inner cylindrical Surface of the double wall device is arranged to a relatively small volume of water, which in the watertight tank device in direct contact with the inner surface of the double-wall device is to thermally isolate, and a water source in communication with the water inlet means stands. 10. Plant according to claim 9, characterized in that the heat barrier device is also a disk-shaped Has heat barrier subdivision (32) which extends horizontally dm substantially transversely to the interior of the watertight Tank device (23) in its upper section 809817/0800 extends and serves to keep the water in the upper section
the watertight tank device from the water in their
thermally insulate the lower section, and that the
Water outlet device for the waterproof 'steering device a first (38) and second (40) water outlet
which are arranged on the opposite sides of the heat barrier subdivision. 11. Plant according to claim 10, characterized in that a pressure-sensitive water flow control valve means (46, 48) is provided, which is on the first
Water outlet (38) is located and in operative communication with the hot fluid inlet means (24) serves so that when the pressure at the hot fluid inlet means is a certain, beforehand
reaches the specified maximum value, the valve device
opens to allow the heated water to flow out of the first water outlet and thereby automatically control the maximum pressure of the hot fluid at the inlet for hot fluid. 12. Plant according to claim 9, characterized in that the cylindrical heat barrier part (28, 30) several Through openings (29) around its circumference immediately below the thermal barrier subdivision (32). 13. Plant according to claim 12, characterized in that the heat barrier subdivision (32) has a plurality of through openings (33). 14. Plant according to claim 13, characterized in that the heat barrier part (28, 30) has a plurality of through holes (31) around its circumference immediately above
the thermal barrier subdivision (32). 809817/0600 "- 6 ■" 15. Plant according to claim 9, characterized in that the Doppelwamloinrichtung (18) has the shape of a Has a pair or two metal plates, which are welded together with fluid channels there / wipe, to a purifying agent conveying heat transfer part form. 16. Combined storage tank and heat exchanger unit for heating and storing a liquid such as Water or the like, characterized by a liquid-tight tank device (23) with a Liquid inlet device (36) and a liquid outlet device (38, 40), and furthermore with a double wall device (18) comprising at least a portion of the outer wall of the liquid-tight tank device forms, an inlet device (24), an outlet device (26) and a channel device, which extends within the double wall device from the inlet device to the outlet device and is sealed against the interior of the liquid-tight tank device, a thermal barrier device (28, 30) mounted on the inside of the liquid-tight tank device is and has a small distance from the inner surface of the double wall device to a relatively Thermally isolate small volume of liquid contained in the liquid-tight tank device is in direct contact with the inner surface of the double wall device, and an outer jacket means for the liquid-tight Tank device with an air inlet (82) and an air outlet (84) at a distance therefrom, with an air duct (76), which extends there between inlet and outlet and through which air can circulate while it is in contact with the outer surface of the double wall device of the 809817/0600 - 7 - liquid-tight tank direction. 17. Unit according to claim 16, characterized in that a fan device (88) in the channel (76) is mounted to induce air, more suitably from the air inlet (82) through the air duct to the Air outlet (84) to flow. 18. Unit according to claim 16, characterized in that the air inlet (82) in the lower portion of the outer jacket means is arranged, and that the air outlet (84) in the upper portion of the outer jacket means is arranged. 19. Unit according to claim 18, characterized in that the fan device (88) at the air inlet (82) is attached. 20. Unit according to claim 16, characterized in that the outer jacket means is an outer one Has jacket part (80) made of insulating material, which surrounds the double-wall device (18) and at a distance therefrom is arranged, and further comprises an insulating material (86) in a first portion of the gap is attached between the double wall device and the outer shell part and here a second section of the space between the double-walled device and the outer jacket that opens the air duct (76) forms. 21. Water heating system, characterized by a source (12) for hot fluid, - A combined storage tank and heat exchanger unit (10; 74) with a watertight tank device (23), in its lower portion a water inlet device (36) and in its upper portion a 809817/0600 Has water outlet means (38, 40) and further comprises a cylindrical double wall means (18), which forms at least a portion of the outer wall of the watertight tank device and inlet means (24) in its upper portion which is in communication with the source of hot fluid is, furthermore a 7 \ uuslaßeinrichtung (26) in its lower portion and a channel means which extends within the double wall means from the inlet to the outlet means through which hot fluid can flow and which is sealed against the interior of the waterproof tank device, the further comprises a thermal barrier device mounted within the waterproof tank device and a cylindrical heat barrier part (38, 40) which is at a small distance from the cylindrical Inner surface of the double wall device is arranged to a relatively small volume of water to thermally insulate that in the watertight tank facility in direct contact with the inner surface the double v / and device is a source of water that is in connection with the Water inlet means stands, and an outer jacket means for the liquid-tight Tank device with an air inlet (82) and an air outlet (84) which are arranged at a distance from one another are, as well as with an air duct (76) which extends there between the inlet and outlet and through the Air can circulate while in contact with the outer surface of the double wall device of the liquid sealed tank facility is in place. 22. Water heating system, characterized by a source (12) for hot fluid, a combined storage tank and heat exchanger 809817/0600 unit (10; 74) with a watertight steering device (23) with a water inlet device (36) in its lower portion and a water outlet device (38, 40) in its upper section, and further with a cylindrical double-wall device (18), which at least forms part of the outer wall of the watertight tank device, an inlet device (24) in its upper one Having portion in communication with the source of hot fluid further comprising outlet means (26) in its lower section as well as a channel device which is located within the double-wall device extends from the inlet to the outlet means through which hot fluid can flow and the opposite the interior of the watertight tank facility is sealed, a source of water in communication with the water inlet means stands, and an outer jacket means for the liquid-tight Tank device with an air inlet (82) and an air outlet (84) which are arranged at a distance from one another are, as well as with an air duct (76) which extends here between the inlet and outlet and through the Air can circulate while in contact with the outer surface of the double-walled device of the liquid-tight Tank facility stands. 23. Plant according to claim 22, characterized in that the outer casing device is an outer casing part (80) comprises insulating material which surrounds the double-wall device (18) and is at a distance therefrom, said outer jacket means further comprising insulating material (86) embedded in a first portion of the gap is attached between the double wall device and the outer shell part and a second portion of the The space between the double wall device and the outer shell part leaves open, the open space being the air duct 809817/0600 - 10 - (76) which extends between the air inlet and air outlet. 809817/0600