Hot water station

Abstract

The invention relates to a hot water station (50, 51, 52) for providing hot drinking water, comprising: a water inlet (55) to which a hot water line can be coupled; a water outlet (57) for providing hot water, to which a line or fitting can be coupled; and a water reservoir (60) coupled between the water inlet (55) and the water outlet (57) and designed to store water, in which the water reservoir (60) comprises a heat exchanger (64) having: a main circuit (100) designed to flow water through the main circuit; and a secondary circuit (200) having a phase change material which is designed to store thermal energy from the hot water in the main circuit (100) as latent heat and to output the thermal energy stored as latent heat into the cold water in the main circuit (100).

Description

Technical Field

[0001] The present invention relates to a hot water station for providing hot potable water. Background Art

[0002] A hot water station is used in a hot water facility for providing and distributing hot water. A typical hot water facility includes: a potable water warmer having a hot water reservoir for the heated water; and one or more take - off stations to which hot water flows from the potable water warmer via a line system. The hot water station is usually used as a hot water transfer point between the line of the potable water warmer and the lines leading to the potable water take - off stations.

[0003] A long line path can result in: providing hot water from the potable water warmer to the take - off station being very time - consuming. When water is not taken for a long time, the water stays in the line system and cools. The cold water must first be drained until hot water is available again at the take - off station. When bacteria (such as Legionella) in the water multiply in large numbers, the water staying in the line system for a long time can lead to hygiene problems.

[0004] In a traditional line system with a long line path, a circulation line is provided for comfort and hygiene reasons, which causes hot water to circulate in the line system and thus always flow through or near the take - off stations, so that hot water is available immediately or after a short time at these take - off stations. When the temperature of the circulating hot water is high enough, bacteria in the water are killed, thus reducing hygiene problems. However, a pump is required for this circulation, and the energy consumed by the pump is as much as the heating of the circulating hot water. The continuously circulating potable water is heated to about 60 degrees Celsius, and the take - off time may be very short. This process is complex and accompanied by heat loss and power consumption. A non - circulating hot water facility is more energy - efficient without a circulation line. Then, for hygiene reasons, the volume in the line path between the potable water warmer and the take - off station should be small so that there is little water in the line. The maximum value of the volume in the line path may be specified by law or construction technology. When the volume in the line between the potable water warmer and at least one of these take - off stations is greater than 3 liters, according to German law, a circulation line or a temperature - maintaining zone is compulsorily specified for hygiene reasons.

[0005] Additionally, the comfort level of a non - circulating hot water facility is lower. When the water in the line path has cooled, when taking water, the water must first be drained at the take - off station, and then hot water from the potable water warmer will be available at the take - off station after a period of time.

[0006] DE 295 03 746 U1 shows a device for heating the cold water in the pipeline between a hot water production facility and a hot water tap. Energy is stored in a heat accumulator as latent heat, i.e., enthalpy change. SUMMARY OF THE INVENTION

[0007] The task is to provide a device that is more comfortable when taking hot water.

[0008] This task is solved by a hot water station having the features of claim 1.

[0009] A hot water station for providing hot potable water is provided with: an inlet to which a hot water line can be coupled; an outlet for providing hot water to which a pipeline or fitting can be coupled; and a water reservoir coupled between the inlet and the outlet and designed to store water. The water reservoir includes a heat exchanger having: a main circuit designed to allow water to flow through the main circuit; and a secondary circuit with a phase change material designed to store the thermal energy of the water from the main circuit as latent heat and output the thermal energy stored as latent heat to the water in the main circuit.

[0010] Hot water is heated potable water or domestic water, and its temperature range is generally from 30°C to 60°C, especially from 45°C to 60°C. The heated water is also referred to as hot water hereinafter. The cooled water that was previously hot water in the hot water facility is also referred to as cold water. It can be cooled to the ambient temperature. The thermal energy of hot water at a temperature higher than the melting temperature of the phase change material is stored as latent heat in the phase change material. The stored latent heat is output to cold water at a temperature lower than the melting temperature of the phase change material and heats it.

[0011] The hot water station can advantageously be used in a non-circulating hot water facility. The hot water station stores hot water dispersedly and is positioned closer to the take-off station than the hot water reservoir of a potable water heater, so that the time until hot water is provided at the take-off station is reduced. Nevertheless, it can also be used in a hot water facility with a circulation line, because in this case, the time until hot water is provided at the take-off station is also shortened.

[0012] In one embodiment, the hot water station is a hot water transfer point and is connected via at least one supply line to a drinking water warmer that supplies water to the hot water station. At least one distribution line leads from the hot water station to a take-up station. An inlet and an outlet are provided on the hot water station for connecting these lines. Although a hot water line can be installed at the inlet, cold water can also flow through this line into the water storage of the hot water station, for example, the cold water is cold in this line. Even if the heating function of the drinking water warmer fails, only cold water will be provided. The water is provided via the outlet. Although hot water should be provided, there are also operating states in which cold water with a temperature lower than the desired output temperature is output first. This is especially the case when starting the hot water station and after a long pause in take-up. One or more distribution lines leading to one or more take-up stations are installed at the outlet. It is also conceivable to install fittings, such as faucets.

[0013] The water storage of the hot water station serves as a decentralized buffer in the hot water facility, which provides hot water closer to the take-up station. Advantageously, the water storage is used to store hot water. Nevertheless, there are operating states in which the water storage contains cold water, which is cooled in the water storage or as cold water flowing in via the inlet. In one embodiment, the water storage has a capacity of 10 liters or less, especially 5 liters or less. When enough hot water has been stored, the water storage can be bypassed by a bypass valve. However, the regular flow of hot water also advantageously promotes the regular heat absorption of the phase change material acting as a heat accumulator.

[0014] The heat exchanger enables the transfer of thermal energy between the substances in the main circuit and the substances in the secondary circuit without the mixing of substances. The component separating the substances advantageously has good heat conduction ability and a large surface area. The water flowing through the hot water station flows through the main circuit.

[0015] The heat exchanger includes a phase change material, and the abbreviation of the English name "phase change material" is "PCM". The secondary circuit includes a phase change material, which stores most of the thermal energy delivered from the main circuit to the phase change material in the form of latent heat during the phase change. In one embodiment, the heat exchanger operates using the phase change from solid to liquid and vice versa from liquid to solid. Since the substances neither flow into nor out of the secondary circuit, the heat exchanger can also be referred to as a (potential) heat accumulator.

[0016] Hot water flowing through and / or stored at a temperature above the melting temperature of the phase change material causes a phase change of the phase change material, such that the molten phase change material stores a portion of the thermal energy of the hot water during the phase change. Nevertheless, especially when hot water is flowing through, water that is still warm enough for the hot water is still provided at the take - off station. The phase change material can, for example, be waxy in the solid state and liquefy when heated. The phase change material can, for example, include hydrates, salts or organic substances such as paraffin wax and fatty acids. When water is not taken for a long time, the heat stored in the phase change material is used to: when the phase change material solidifies, heat the water that has cooled below the melting temperature again. The phase change material solidifies and the thermal energy released therein is output to the stored water again.

[0017] Advantageously, the melting temperature of the phase change material is higher than the predetermined minimum output temperature of the hot water output. The minimum output temperature describes the desired operating parameter. The minimum output temperature depends on the requirements for domestic hot water use and does not necessarily have to be perceived as very hot by the user, but can also be perceived as warm. An exemplary minimum output temperature is about 40 degrees Celsius. The usually predetermined output temperature range that the hot water output should have is between 40 degrees Celsius and 60 degrees Celsius, especially between 45 degrees Celsius and 60 degrees Celsius, which is sufficient for domestic hot water use. Advantageously, the hot water flowing into the inlet is also within this temperature range. The melting temperature of the phase change material is advantageously between 40 degrees Celsius and 50 degrees Celsius, especially between 42 degrees Celsius and 48 degrees Celsius, so that the flowing hot water melts the phase change material. The same applies to the water heated at the hot water station. The phase change during solidification occurs within the desired output temperature range, especially above the minimum output temperature, so that the cooled water in the main circuit or the incoming cold water causes the solidification of the phase change material and the heat release of the secondary circuit, which inhibits cooling or heating of the cold water.

[0018] In one embodiment, the hot water station is designed to electrically heat the stored water. The hot water heated by the hot water station can have the same temperature range as the hot water provided by the hot water storage tank; however, it can be stipulated that the hot water station heats the hot water to a higher temperature, for example 60 degrees Celsius.

[0019] The electrical heating can support the supply of hot water in such a way that the stored water is heated again after cooling below a predetermined threshold (such as the minimum output temperature) in order to counteract this cooling, so that there is always hot water available in the water storage tank. This can be repeated several times. The energy required for this is much less than in the case where no phase change material is provided. Heating at a predetermined time (such as in the morning) ensures that hot water is usually available when needed. When the water in the water storage tank is electrically heated, the above - mentioned interaction between the hot water and the phase change material also occurs. The thermal energy conveyed to the water in this way is also stored in the heat exchanger.

[0020] The embodiment of the electric heating device for heating is designed to heat the water cooled in the water storage tank or stored as cold water flowing into the water storage tank. The inflowing cold water may be cooled in the pipeline or from a damaged drinking water heater. Advantageously, the stored water is heated to at least 55 degrees Celsius, especially at least 60 degrees Celsius, so that the water is provided and / or stored as hot water.

[0021] In one embodiment, the water storage tank includes a heat insulation part, which slows down the cooling of the stored hot water. The heat insulation part is also called the thermal insulation part. The heat insulation part can be designed such that the hot water remains warm enough for at least 24 hours, that is, hotter than the predetermined minimum output temperature. Especially in combination with the previous electric heating, the hot water always remains hot enough for output. The heat insulation part can be arranged on the outside of the water storage tank and includes insulating materials.

[0022] In one embodiment of the heat exchanger, a plurality of main circuits are provided, which are thermally coupled to the secondary circuit. Therefore, separate first and second main circuits can be provided such that no water exchange occurs between the two main circuits. Each main circuit can transfer thermal energy to the secondary circuit, so that the phase change material melts, and the thermal energy from the secondary circuit can be transferred to the main circuit during solidification. The secondary circuit is designed to store the thermal energy of the hot water from the first and / or second main circuits as latent heat and output the thermal energy stored as latent heat to the cold water in the first and / or second main circuits. This concept is not limited to two main circuits, but more than two main circuits can be provided, which are thermally coupled to the same secondary circuit.

[0023] The embodiment of the hot water station with two main circuits in the heat exchanger combines the functions of two hot water stations because it provides drinking water for two hot water branches, such as for the bathroom and kitchen of an apartment. Therefore, for example, a shower process of taking hot water from the hot water branch for a long time can store the thermal energy in the heat exchanger, and this thermal energy is then output in another hot water branch for water use in the kitchen. This embodiment additionally improves the efficiency because the phase change material acting as a storage absorbs heat by taking hot water from one of these main circuits, and this heat-absorbing energy storage is also available for another main circuit.

[0024] In one embodiment, the heat exchanger is designed as a plate heat exchanger. Alternatively, the heat exchanger may have finned tubes or an aluminum body, in particular with a large surface area. Thereby, multiple degrees of freedom are provided for the design of the heat exchanger. Alternatively, in one embodiment, one or more, in particular two, hollow cylinder-shaped chambers with a phase change material may be provided for the secondary circuit, and one or more, in particular two, hollow cylinder-shaped water chambers may be provided for the primary circuit. The chambers for the primary circuit and the secondary circuit are arranged alternately such that these hollow cylinder-shaped chambers are arranged nested within each other.

[0025] A pressure regulator may be provided in the hot water station so as to reduce the pressure of the incoming water at the inlet if the incoming water is provided at a relatively high pressure. A relatively high pressure may be used in the hot water facility so as to enable a relatively long pipeline path with a relatively small cross-section to be conducted without a circulation line. The operating pressure of the embodiment of the hot water station permanently lies within the range of 6 bar, wherein the pressure shock may be up to 10 bar.

[0026] In one embodiment, the water reservoir is designed as a small water reservoir with a capacity of 2 liters or less, in particular 1 liter or less and in particular 0.5 liters or less. With such a water reservoir, the hot water station is not used as a transfer point but as a micro storage station for providing hot water in the immediate vicinity of the dispensing station. The micro storage station is a compact small hot water station, which is designed, for example, as an under-counter hot water station for installation under a washbasin. The less water is stored, the more compact the micro storage station is. In the hot water facility, the optional micro storage station increases the comfort level with respect to the hot water supply time, which is again reduced by a few seconds.

[0027] The micro storage station advantageously includes a heat insulation part so as to slow down the cooling of the water. Advantageously, a heating device is also provided in the micro storage station. Description of the Drawings

[0028] Subsequently, some embodiments will be described in more detail with reference to the drawings. Among them:

[0029] Figure 1 An embodiment of the hot water facility is schematically shown;

[0030] Figure 2 An embodiment of the hot water station is schematically shown;

[0031] Figure 3 A cross-section of an embodiment of the heat exchanger is schematically shown;

[0032] Figure 4 A cross-section of another embodiment of the heat exchanger is schematically shown;

[0033] Figure 5Schematically shows another embodiment of a hot water facility;

[0034] Figure 6 Schematically shows another embodiment of a hot water station;

[0035] Figure 7 Schematically shows a section of yet another embodiment of a heat exchanger;

[0036] Figure 8 Schematically shows a section of yet another embodiment of a heat exchanger;

[0037] Figure 9 Shows a three - dimensional view of another embodiment of a hot water station;

[0038] Figure 10 Shows a three - dimensional view of the bottom area of a hot water station;

[0039] Figure 11 Shows a schematic view of the head area of a hot water station;

[0040] Figure 12 Shows a three - dimensional view of the head area of a hot water station; and

[0041] Figure 13 Shows a cross - sectional view of a hot water station.

[0042] In these drawings, identical or functionally identical components are provided with the same reference numerals. Detailed Description

[0043] Figure 1 Schematically shows an embodiment of a hot water facility having two hot water stations 51, 52. The hot water facility includes a drinking water heater 1 with a hot water storage tank 3, and exemplarily includes a first and a second hot water station 51, 52 and four take - off stations 71, 72, 73, 74. The drinking water heater 1 heats the cold drinking water flowing into the hot water storage tank 3 via a plant interface 21 and stores it in the hot water storage tank 3 for use. The typical temperature of the hot water in the hot water storage tank 3 is 52 degrees Celsius. Exemplarily, heating is performed by a heat exchanger of a heat pump or a gas furnace, however, it is not limited to these heating mechanisms.

[0044] A line system 9 with a non - circulating line is provided between the drinking water heater 1 and the tapping stations 71, 72, 73, 74. The line system is designed such that hot water flows from the hot water storage 3 of the drinking water heater 1 to these tapping stations 71, 72, 73, 74. Hot water can be tapped at these tapping stations 71, 72, 73, 74 and can flow out of the hot water facility. The tapping stations 71, 72, 73, 74 can be designed, for example, as shower heads or faucets. Two of the tapping stations 71, 72 and 73, 74 are respectively coupled to one of the hot water stations 51, 52 such that water flows from the drinking water heater 1 through the first or second hot water station 51, 52 to the tapping stations 71, 72 and 73, 74.

[0045] The hot water stations 51, 52 are hot water transfer points and are respectively coupled to the drinking water heater 1 via supply lines 11. Distribution lines 13 lead from the hot water stations 51, 52 to the tapping stations 71, 72, 73, 74. Multiple interfaces can be provided at the hot water stations 51, 52 for connecting the distribution lines 13 to the tapping stations 71, 72, 73, 74. Advantageously, multiple tapping stations, as Figure 1 shown, are installed in a row such that the distribution line 13 bypasses through the additional tapping stations 71, 73 to the farthest tapping stations 72, 74. The line volume in the pipeline of each line path from the drinking water heater 1 to one of the tapping stations 71, 72, 73, 74 is less than or equal to a predetermined maximum line volume. This embodiment of the hot water facility is a small - scale facility in the sense of the German drinking water regulations, where the maximum line volume of each line path must be equal to or less than 3 liters. In addition, the volume of the drinking water storage in the system must be less than or equal to 400 liters. Different from large - scale facilities, for such small - scale facilities, the mandatory annual microbiological testing of the drinking water is omitted.

[0046] A hot water facility with two hot water stations 51, 52 can be provided, for example, for two small apartments in which the hot water stations 51, 52 are respectively arranged. For a two - person apartment, one hot water station is sufficient for the tapping locations in the kitchen and the bathroom. Alternatively, the hot water facility can be provided for larger apartments of three to four people. Then, the hot water stations 51, 52 are respectively provided for the bathroom and the kitchen and their tapping locations.

[0047] In a hot water facility for multiple residential units, such as in a multi - unit building or a duplex apartment, more than two hot water stations 51, 52 are provided, where the hot water facility is a small - scale non - circulating line facility. This can also be achieved in a multi - unit building with a long line path, high water pressure, and a small pipe cross - section.

[0048] In this embodiment, two hot water branches 10, 20 are provided. Among them, water is guided to one or more tapping stations 71, 72 or 73, 74 through a supply line 11 and one or more distribution lines 13. In each of the hot water branches 10, 20, the water flows through one of the hot water stations 51, 52. On the one hand, hot water is guided from the potable water heater 1 to the first and second tapping stations 71, 72 in the first hot water branch 10, and on the other hand, hot water is guided from the potable water heater 1 to the third and fourth tapping stations 73, 74 in the second hot water branch 20. The hot water branches 10, 20 are separate so that no water exchange occurs. These hot water branches have separate supply lines 11 and separate distribution lines 13. In each of the hot water branches 10, 20, the line volume in the pipeline of the line path is less than or equal to a predetermined maximum line volume of 3 liters. Cold water is separately guided to the tapping stations 71, 72, 73, 74 via a pipeline 19 for cold water and separately from the hot water facility.

[0049] The hot potable water from the potable water heater 1 that flows into the supply line 11 and the distribution line 13 during tapping but is no longer tapped will cool down. During the next tapping, this cooled water must first flow out until hot water from the potable water heater 1 is provided again at the tapping stations 71, 72, 73, 74. The hot water stations 51, 52 shorten the time until hot water is provided again at the tapping stations by being able to store hot water and advantageously also being able to heat cold water.

[0050] Figure 2 The structure of an embodiment of the hot water station 51 is schematically shown. In Figure 1 the exemplary hot water facility, this hot water station can be used as the first and second hot water stations 51, 52. However, its use is not limited to this kind of hot water facility.

[0051] The hot water station 51 has: an inlet 55 that is connected to the supply line 11; and an outlet 57 that is connected to the distribution line 13, such that the hot water branch 10 extends through the hot water station 51. The arrows indicate the inflowing water 111 and the outflowing water 131.

[0052] In this embodiment, an optional pressure regulator 31 is provided on the inlet side to reduce the pressure of the inflowing water at the inlet 55 if water with a high pressure is provided. High pressure can be used in the hot water facility to conduct a longer line path with a smaller cross-section without a circulation line. In another embodiment, the pressure regulator can be connected upstream of the inlet 31 if necessary.

[0053] The hot water station 51 includes a water storage device 60 which is designed to store water. In order to distinguish it from the large hot water storage device 3 of the drinking water warmer 1, this water storage device 60 can also be intuitively called a small hot water storage device. The storage volume of the water storage device 60 is smaller than that of the hot water storage device 3 in the drinking water warmer 1. A typical value is 5 liters. In the hot water facility, the storage volume of the water storage device 60 is not included in the line volume which should be less than the maximum volume. However, the total volume of all water storage devices in the system must be equal to or less than the maximum storage volume, that is, 400 liters, so that the hot water facility is a small facility in accordance with the German drinking water regulations.

[0054] The water storage device 60 has a heat insulation part 62 which greatly slows down the cooling of the stored hot water. This heat insulation part 62 is arranged on the outer side of the water storage device 60. The heat insulation part can include heat storage materials with insulation.

[0055] The water storage device 60 is designed to electrically heat the water. When there is cold water in the water storage device 60, whether it is cold water from the line or it has cooled down, it can be electrically heated. Thus, even if there is no water extraction for a long time, there is hot water available in the water storage device 60. Therefore, in one embodiment, it is heated to 60 degrees Celsius after a long downtime. For example, once the temperature of the stored water drops below a predetermined threshold (such as a predetermined minimum output temperature), heating can be carried out until the temperature in the water storage device 60 rises above another predetermined threshold. When the water temperature drops again, this process can be repeated. For heating, a heating element 66 is provided as a heating device, and this heating element can have an exemplary power consumption of 100 watts. This value is much lower than the power consumption of the continuous heater in the station for heating the water.

[0056] The water storage 60 includes a heat exchanger 64 having a main circuit for potable water and a secondary circuit with a phase change material (hereinafter referred to as PCM). Exemplary embodiments of the heat exchanger 60 are plate heat exchangers, finned tubes with large surfaces, or heat exchangers with an aluminum body. The phase change material stores most of the thermal energy conveyed from the main circuit to the phase change material in the form of latent heat, which is absorbed during the phase change from the solid state to the liquid state. The latent heat is also referred to as the enthalpy change, where, in this embodiment, the sublimation enthalpy and the melting enthalpy are relevant. The phase change can take place at a melting temperature of approximately 45 degrees Celsius. The phase change material can, for example, include hydrates, salts, or organic substances such as paraffins and fatty acids. The phase change takes place approximately below or within the desired output temperature range of the hot water output. The hot water flowing through and / or electrically heated by the hot water station causes a phase change of the phase change material and stores a part of the thermal energy of the hot water. Nevertheless, even when taking hot water whose thermal energy has been partially used for the phase change, sufficient hot water is provided at the take-off points 71, 72, 73, 74. When not taken for a long time, the thermal energy stored in the phase change material is used to prevent or slow down the cooling of the stored water. The phase change material solidifies when the water in the main circuit cools or is cooled, and the thermal energy released here is output to the stored or flowing water and warms it up.

[0057] For example, hot water at approximately 50 degrees Celsius from the supply line 11 can cause a phase change of the phase change material that liquefies within this temperature range. Nevertheless, although the phase change has occurred, hot water at approximately 40 degrees Celsius can still be taken at the take-off points 71, 72, 73, 74.

[0058] The combination of the heat exchanger 64 with the phase change material, the heating device 66, and the insulation 62 significantly reduces the energy requirement for providing hot water near the take-off points 71, 72, 73, 74. Compared to continuous heaters in the station, the energy requirement of the hot water station 51 is reduced to approximately one-seventh. The insulation 62 can keep the water temperature for at least 24 hours, so that hot water can be taken without being reheated. With the hot water station 50, hot water can already be provided at the take-off points 71, 72, 73, 74 after 8 to 15 seconds. In addition, the heat exchanger 64 designed as a plate heat exchanger has a low pressure loss and enables a flow rate of 15 liters per minute.

[0059] The hot water station 51 with the water storage 60 has exemplary dimensions of 540 x 300 x 82 mm. The weight is approximately 9 kg. A 1 / 2" IG connection is provided. For on-site installation at the transfer point, an internal pipeline made of stainless steel with a 1 / 4" IG connection is provided. In one embodiment, the pipeline can be provided as an original design or a finished design. Alternatively, the pipeline can already be installed on the hot water station 51 at the time of delivery.

[0060] The hot water station 51 significantly shortens the time until hot water is provided at the point of use. By providing optional micro storage stations 80 at the points of use 71, 72, 73, 74, an even shorter time until provision is possible.

[0061] Figure 1 It is shown that: in this embodiment of the hot water facility, the points of use 71, 72, 73, 74 each have a micro storage station 80 in which hot water can be stored in the immediate vicinity of the outlet of the points of use 71, 72, 73, 74. The micro storage station 80 is a compact and small-scale implementation of the hot water station. The micro storage station can for example be designed as an under-counter storage station. Such an under-counter storage station can be unobtrusively installed under a washbasin or in a washbasin base cabinet. The micro storage station 80 can generally store a maximum of 0.5 litres of water. The optional micro storage station 80 increases the comfort with respect to the hot water provision time. This hot water provision time is reduced to less than 8 seconds. A typical value is 5 seconds.

[0062] The micro storage station 80 is constructed analogously to the hot water station 51 described in connection with Figure 2 and has a small water storage and advantageously also the other features described above, namely the insulation and the heating device, in order to provide hot water.

[0063] The micro storage station 80 includes insulation in order to slow down the cooling of the water. Advantageously, in the micro storage station 80 there is also provided: a heating device which for example has a heating element; and a heat exchanger with a phase change material, the mode of action of which has been described above. The electrical power consumption of the micro storage station 80 is in the range of 50 watts.

[0064] The storage volume of the micro storage station 80 is also not counted into the line volume which must be less than a maximum volume of 3 litres in order for the hot water facility to be a small-scale facility. Since the storage capacities of the water storages in the hot water stations 51, 52 and in the micro storage station are not part of the line volume, the maximum line volume is not exceeded even in this embodiment. However, the storage volume of the micro storage station 80 is counted into the total volume of all water storages in the system which must be less than a maximum storage volume of 400 litres in order to be a small-scale facility.

[0065] The efficient series of water storages 60 in the hot water stations 51, 52, especially in combination with the optional micro storage station 80, significantly shortens the time until hot water is provided at the points of use 71, 72, 73, 74 compared to conventional hot water facilities.

[0066] Hot water stations 51, 52 with water storage 60 and micro storage stations 80 have very low power consumption, especially compared to stations with continuous heaters. Compared to the power consumption of stations with continuous heaters, the power consumption of the optional micro storage station 80 and hot water stations 51, 52 with water storage 60 is almost negligible. This advantage is particularly evident in large systems with multiple hot water stations 51, 52 and thus also multiple residential units. Compared to traditional systems or systems with continuous heaters in the stations, due to the low energy consumption, for example, the power consumption is 50 to 100 watts, the total grid connection power is significantly smaller. In multiple hot water stations 51, 52, there is no longer a need for simultaneous locking to limit the number of hot water stations 51, 52 operating simultaneously. A smaller line cross-section can be used for power supply. No additional substations are required. Then, this generally lower power supply cost also leads to a reduction in the planning cost of the system and especially the power supply.

[0067] Figure 3 A section of an embodiment of the heat exchanger 64 is schematically shown, which is designed as a plate heat exchanger. Such a heat exchanger 64 can be provided in the hot water stations 51, 52 or in the micro storage station 80. The phase change material of the secondary circuit 200 and the water of the primary circuit 100 are alternately arranged between the plates. Hot water with a temperature higher than the melting point of the phase change material outputs thermal energy to the secondary circuit 200 with the solid phase change material, so that the phase change material melts and stores the latent heat from the hot water in the melted phase change material. If cold water with a temperature lower than the melting point is in the primary circuit 100, when the phase change material solidifies, the thermal energy that has been stored as latent heat in the phase change material is output to the cold water in the primary circuit 100 and warms it.

[0068] Figure 4 A section of the heat exchanger 64 is schematically shown, which exemplarily has finned tubes 92 through which the water flow of the primary circuit 100 passes. The phase change material in the secondary circuit 200 is arranged outside the finned tubes 92. The finned tubes 92 are tubular members that have fins 94 on their outer sides for increasing the tube surface. This improves the heat transfer between the inside and outside of the tubes. Advantageously, the finned tubes 92, especially the fins 94, are made of a material with good thermal conductivity.

[0069] The design of the heat exchanger 64 is not limited to the embodiments mentioned. Good heat transfer, a large surface for transferring thermal energy, and also the weight (taking into account the preferred wall-mounted installation) are all key points that play a role in the design. Therefore, another embodiment of the heat exchanger 64 includes an aluminum body with a large surface.

[0070] Figure 5 Another embodiment of the hot water facility is schematically shown. The following description focuses on the comparison with Figure 1 the previous embodiments inFigures 2 to 4 Differences between the described hot water stations 51 and 52.

[0071] In this embodiment, two hot water branches 10 and 20 are provided. Through these hot water branches, on the one hand, hot water is conveyed from the drinking water heater 1 to the first and second take - off stations 71 and 72 in the first hot water branch 10, and on the other hand, hot water is conveyed from the drinking water heater 1 to the third and fourth take - off stations 73 and 74 in the second hot water branch 20. Although these hot water branches 10 and 20 are separate and there is no water exchange between them, both flow through the same hot water station 50. These hot water branches have separate supply lines 11 and separate distribution lines 13. As in the previous embodiment, the hot water branches 10 and 20 are configured for a bypass installation and have a micro - storage station 80.

[0072] In each of the hot water branches 10 and 20, the line volume in the pipeline of the line path is less than or equal to a predetermined maximum line volume of 3 liters.

[0073] The two hot water branches 10 and 20 extend through two main circuits 100 and 102 of the heat exchanger 64 in the hot water station 50.

[0074] Figure 6 An embodiment of the hot water station 50 is schematically shown, which can be used in the above - mentioned hot water facility.

[0075] As in the previous embodiment, the hot water station 50 includes a water storage tank 60, a heat insulation part 62, a heat exchanger 64, and a heating element 66 as a heating device. Since the hot water station 50 is provided for two hot water branches 10 and 20, the hot water station has a water inlet 55 for the supply line 11 and an outlet 57 as an interface for its distribution line 13 in duplicate. In the case of more than two main circuits, the fittings for the inlets and outlets will also be provided in multiples accordingly, but these fittings can be designed in the same way. Since the hot water station 50 stores more water to supply the two hot water branches 10 and 20, the housing size is also larger than that of the previous embodiment. An optional pressure regulator 31 is provided on the inlet side.

[0076] Supply lines 11 are connected at the first and second water inlets 55, and distribution lines 13 are connected at the first and second water outlets 57. The inflowing and outflowing water 111, 131 of the first hot water branch 10 flows through the first water inlet 55 or the first water outlet 57, and the inflowing and outflowing water 112, 132 of the second hot water branch 20 flows through the second water inlet 55 or the second water outlet 57. There is no mixing of the potable water between these hot water branches 10, 20. There is also no mixing in the hot water station 50. In addition to the separate distribution lines 13, the hot water branches 10, 20 also have separate supply lines 11, which extend between the potable water heater 1 and the hot water station 50.

[0077] The secondary circuit of the heat exchanger 64 includes a phase change material and interacts with the two primary circuits such that thermal coupling is effected via the secondary circuit, since heat from each of these primary circuits can be stored in the secondary circuit and heat can be output from the secondary circuit to each of these primary circuits. Thus, the phase change material can absorb heat via one of these primary circuits, and the stored thermal energy can then be output to the other primary circuit.

[0078] Figure 7 A section of the heat exchanger 64 is schematically shown, which is exemplary designed as a plate heat exchanger. The phase change material of the secondary circuit 200 and the water of the first and second hot water branches 10, 20 are alternately arranged between these plates, which flow through the first and second primary circuits 100, 102. However, the water of the first primary circuit 100 and the water of the second primary circuit 102 flow through these plates spatially separated, preferably on alternately arranged flow paths, such that the water in the first primary circuit 100 flows past the phase change material between two adjacent plates on one side and the water in the second primary circuit 102 flows past on the other side. Thus, the thermal energy stored in the phase change material can be transferred from the secondary circuit 200 to the first and second primary circuits 100, 102, even if the storage of the thermal energy is only caused by the withdrawal in one of these primary circuits 100, 102. Nevertheless, both primary circuits 100, 102 can cause the phase change material to absorb heat.

[0079] For example, a shower process, which usually withdraws a large amount of hot water in the first hot water branch 10 over a long period of time, can cause thermal energy to be stored in the secondary circuit 200 in the first primary circuit 100. Then, this energy can be output via the second primary circuit 102 for withdrawing hot water in the kitchen in the second hot water branch 20, but can also be used, for example, for washing hands in the bathroom provided in the first hot water branch 10.

[0080] Figure 8A cross-section of an embodiment of a heat exchanger 64 is schematically shown, which has finned tubes 92 through which the water flows in the main circuits 100, 102. There are first and second finned tubes, and the water in the first or second main circuit 100, 102 flows through the first and second finned tubes without liquid exchange. Advantageously, the tubes 92 are arranged alternately such that the first tube is adjacent to the second tube and vice versa.

[0081] Previous combinations of the hot water station and its use Figures 1 to 4 The other features described, namely the insulation part and the heating of the stored water, are also provided in Figures 5 to 8 the hot water station 50 in order to heat the water in the hot water station 50 for two hot water branches 10, 20 and slow down the cooling of the water. Thus, the insulation part 62 can keep the hot water hot enough for up to 24 hours for use. In this embodiment, a 100-watt heating element 66 is also provided, by means of which the cooled water in the water storage tank 60 can be heated to 60 degrees Celsius after a long downtime.

[0082] Combination of the hot water station 50 Figures 5 to 8 The described embodiment has the combination with the hot water stations 51, 52 Figures 1 to 4 The same advantages as the described embodiment. In the two hot water branches 10, 20, the line volumes are respectively equal to or lower than a predetermined value, especially the line volume is equal to or less than three liters. Since the take-off stations 71, 72, 73, 74 are supplied through the two hot water branches 10, 20, the flow rates at the take-off stations 71, 72, 73, 74 are higher in the case of the hot water station 50 with more than 20 liters per minute. Although less energy is required, the drinking water supply is more efficient. The planning and implementation of using the hot water station 50 in the hot water facility are also simplified because when two hot water stations 51, 52 are provided for the two hot water branches 10, 20, only one installation path is provided instead of two installation paths. Even if the hot water station 50 has the same or similar power consumption of 100 W as the previous embodiment, providing the thermal energy stored in the secondary circuit 200 for the two main circuits 100, 102 results in improved efficiency.

[0083] Figure 9 Another embodiment of the hot water station 50 is shown. The hot water station 50 has an elongated basic shape with two columns and end-side fastening areas 96, and the fastening areas are designed as foot-shaped widening parts with flat support surfaces. Through the holes 97 in the fastening areas 96, fastening devices, such as screws, can be guided to fasten the hot water station 50, for example, to a wall.

[0084] Inside the columnar main module 98, a heat exchanger with a phase change material is provided. This is used to warm the cooled water in the chamber of the main module 98. Electrical equipment and cables connecting electrical components at both end sides extend in a protective tube 99 arranged beside the main module 98 in the longitudinal direction.

[0085] The hot water station 50 has a length exceeding one meter, and the length is usually in the range of 1.5 meters.

[0086] The hot water station 50 has: a first end side region, which can also be referred to as the bottom region 81; and an opposite second end side region, which can also be referred to as the head region 82. In the bottom region 81, water flows in from the drinking water warmer 1, and water flows out to the take - off stations 70, 71, 72, 73, 74. In the head region 82, interfaces for supplying electrical components, communication devices, and control units are provided. The heating device is also provided in the head region 82. The heating device can be designed, for example, as a 50W heater with a heating rod. This heating device is used when the phase change material is less filled and the heat absorption is insufficient. The sensor lines extend in the protective tube 99 to the volumetric flow meters in the bottom region 81, and these volumetric flow meters detect the water flow.

[0087] Although referred to as the head and bottom regions 82, 81, the orientation of the installed hot water station 50 is not limited to the Figure 9 vertical orientation shown. The hot water station 50 can also be installed in an inverted, horizontal, or inclined orientation, preferably in a built - in installation.

[0088] Figure 10 The bottom region 81 of the hot water station 50 is shown, which has an inlet and an outlet of the hot water station 50, such that water flows in and out at the same end side, which simplifies the installation. Water from the drinking water warmer enters at the inlet 55, and the water is guided into the inner water chamber 151. The water flows through the inner water chamber 151 to the head region 82 of the hot water station 50, and there it turns into the outer water chamber 512, and the water then flows back through this outer water chamber to the bottom region 81 and reaches the outlet 57, at which water is provided for the take - off stations 70, 71, 72, 73, 74.

[0089] Figure 11 The interior of the hot water station 50 is schematically shown, which has a bypass chamber 84 in the head region 82 of the main module 98, and water flows through this bypass chamber from the inner water chamber 151 to the outer water chamber 152. The height of the bypass chamber 84 is in the range of 10 mm.

[0090] Figure 12The head region 82 of the main module 98 is shown, which has filling openings 85 in the bypass chamber 84. Through these filling openings 85, the main module 98 can be filled with the phase change material. The outflow from the inner water chamber 151 and the inflow into the outer water chamber 152 are achieved through the annular gap 86.

[0091] Figure 13 A cross-section of the hot water station 50 with the main module 98 and the protective tube 99 is shown. In the main module 98, two chambers filled with the phase change material are provided, namely the inner chamber 201 and the outer chamber 202, as the secondary circuit, and the inner and outer water-guiding chambers 151, 152 are provided as the main circuit. These water-guiding chambers have the shape of a hollow cylinder. The inner water chamber 151 is arranged between the two chambers 201, 202 with the phase change material 250. The chambers 201, 202 with the phase change material 250 have walls and internally have a structural part 260 made of aluminum, which enables good heat transfer. These structural parts 260 increase the surface area of the chambers 201, 202 and have a cross-section with radially extending tabs that can branch in a forked manner. The outer chamber is a vacuum chamber 270 for thermal insulation, which surrounds the chambers 201, 202 with the phase change material 250 and the water chambers 151, 152.

[0092] An electric heating rod is installed at the center of the inner chamber 201 with the phase change material 250. In one embodiment, the electric heating rod is approximately 200 mm long and is positioned in the head region 82 or adjacent to the head region 82.

[0093] The cooled water from the pipeline first flows through the inner water chamber 151 and then through the outer water chamber 152. During the water flowing through the water chambers 151, 152, the water absorbs the heat stored in the phase change material 250, so that the water has a temperature of approximately 45 degrees Celsius when flowing out of the hot water station 50. After the cooled water has passed through the device and has been heated by the phase change material 250 that has solidified here, hot water with a temperature of approximately 53 degrees Celsius flows out of the hot water storage tank 3 and causes the phase change material 250 to absorb heat again. If hot water is not taken for a long time, the phase change material 250 can be maintained at a certain temperature with little energy consumption so that the phase change material does not solidify.

[0094] Advantageously, the features described above and in the claims and derivable from the drawings can be implemented not only individually but also in different combinations. The present invention is not limited to the described embodiments but can be modified in various ways within the scope of professional knowledge.

[0095] Reference numerals

[0096] 1 Drinking water heater

[0097] 3 Hot water storage

[0098] 9 Circuit system

[0099] 11 Supply line

[0100] 10, 20 Hot water branch

[0101] 13 Distribution line

[0102] 19 Cold water line

[0103] 21 Plant interface

[0104] 31 Pressure regulator

[0105] 50, 51, 52 Hot water station

[0106] 55 Inlet

[0107] 57 Outlet

[0108] 60 Water storage

[0109] 62 Heat insulation part

[0110] 64 Heat exchanger

[0111] 66 Heating element

[0112] 70, 71, 72, 73, 74 Take - off station

[0113] 80 Miniature storage station

[0114] 81 Bottom area

[0115] 82 Head area

[0116] 84 Flow - around chamber

[0117] 85 Filling opening

[0118] 86 Void

[0119] 92 Finned tube

[0120] 94 Fin

[0121] 96 Fastening area

[0122] 97 Hole

[0123] 98 Main module

[0124] 99 Protection tube

[0125] 100, 102 Main circuit

[0126] 111, 112 Inflowing water

[0127] Water flowing out of 131 and 132

[0128] 151 and 152 water chambers

[0129] 200 secondary loop

[0130] 201 and 202 chambers

[0131] 250 phase change material

[0132] 260 structural part

[0133] 270 vacuum chamber

Claims

1. A hot water station (50, 51, 52) for providing hot potable water, said hot water station having: an inlet (55) to which a hot water line can be coupled; an outlet (57) for providing hot water to which a pipeline or fitting can be coupled; and a water reservoir (60) coupled between said inlet (55) and said outlet (57) and designed to store water, wherein, The water reservoir (60) includes a heat exchanger (64) having: a main circuit (100) designed to allow water to flow through the main circuit; and a secondary circuit (200) having a phase change material designed to store the thermal energy of the water in the main circuit (100) as latent heat and output the thermal energy stored as latent heat to the water in the main circuit (100).

2. The hot water station (50, 51, 52) according to claim 1, wherein, The melting temperature of the phase change material is higher than the predetermined minimum output temperature of the output hot water.

3. The hot water station (50, 51, 52) according to claim 1 or 2, wherein, The predetermined output temperature range of the output hot water is between 45 degrees Celsius and 60 degrees Celsius.

4. The hot water station (50, 51, 52) according to claim 2 or 3, wherein, The melting temperature of the phase change material is between 40 degrees Celsius and 50 degrees Celsius, especially between 42 degrees Celsius and 48 degrees Celsius.

5. The hot water station (50, 51, 52) according to any one of the preceding claims, said hot water station being designed to electrically heat the stored water.

6. The hot water station (50, 51, 52) according to any one of the preceding claims, said hot water station having an electric heating device (66) designed to heat the stored water that has cooled in said water reservoir (60) or that flows into said water reservoir (60) as cold water.

7. The hot water station (50, 51, 52) according to claim 5 or 6, said hot water station being designed to electrically heat the stored water to at least 55 degrees Celsius or equal to 55 degrees Celsius, in particular at least 60 degrees Celsius or equal to 60 degrees Celsius.

8. The hot water station (50, 51, 52) according to any one of the preceding claims, wherein, The water reservoir (60) includes a heat insulation part (62) that slows down the cooling of the stored hot water.

9. The hot water station (50, 51, 52) according to claim 8, wherein, The heat insulation part (62) includes a heat insulating material disposed outside the water reservoir (60).

10. The hot water station (50, 51, 52) according to any one of the preceding claims, wherein, The main circuit (100) is a first main circuit (100) separate from the second main circuit (102) of the heat exchanger (64).

11. The hot water station (50, 51, 52) according to claim 10, wherein, The secondary circuit (200) has one or more hollow cylindrical chambers (201, 202) with a phase change material, and the main circuit (100) has one or more hollow cylindrical water chambers (151, 152) nested with each other.

12. The hot water station (50, 51, 52) according to claim 10 or 11, wherein, The secondary circuit (200) is designed to store the thermal energy of the water in the first and / or second main circuits (100, 102) as latent heat and output the thermal energy stored as latent heat to the water in the first and / or second main circuits (100, 102).

13. The hot water station (50, 51, 52) according to any one of the preceding claims, wherein, The heat exchanger (64) is designed as a plate heat exchanger, or has finned tubes (92) or an aluminum body.

14. The hot water station (50, 51, 52) according to any one of the preceding claims, the hot water station is designed as a micro storage station (80), wherein, The water reservoir (60) has a capacity of 2 liters or less, especially 1 liter or less and especially 0.5 liters or less.

15. The hot water station (50, 51, 52) according to any one of the preceding claims, wherein, The hot water station is designed as an under-counter hot water station.

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