DE102012101276A1 - Heat exchanger for a heating system or a heat supply system - Google Patents

Abstract

The invention relates to a heat exchanger for a heating system or a heat supply system in the form of a tubular heat exchanger with a closed container in which the interior is filled with a first medium that supplies heat amounts, and a second medium that dissipates amounts of heat in the coil of the same located. The invention further relates to the design of such heat exchangers with a small size and high efficiency and high specific power.

Description

The invention relates to a heat exchanger for a heating system or a heat supply system.

In heating or heat supply systems, there is often a need to provide a medium adapted to the conditions of the consumer from the media arriving with different parameters in terms of quantity and fluid temperature. The various heat sources may be, for example, conventional boilers, thermal solar collectors, geothermal probes, or the like.

Heat sinks are commonly used for this task, and heat transfer between the media is achieved by means of separate conduit circuits. The general task for this application is to apply that from incoming heat quantities in the shortest possible time a heated heating medium is generated, which corresponds to the requirements in terms of media temperature and quantity.

For a long time it has been known that on the side of energy production there are significant differences in the media parameters. For example, conventional boilers supply media with temperatures of 40 ° C and more. Solar thermal collectors require their own media circulation. Geothermal probes supply media with temperatures between 30 ° C and more than 100 ° C. On the consumer side, a heating circuit may require temperatures between 35 ° C and 80 ° C, while service water must be provided at temperatures above 55 ° C.

In addition, certain circuits must be kept separate from other circuits. For example, the circuit of a solar thermal collector contains a frost-proof medium, while in the circuit of a boiler is not necessary. On the consumer side there are also differences between a line circuit for heating purposes and a line circuit for process water, which must have drinking water quality and therefore must be fed with fresh water.

Since a merging of the different media with the same different heat contents is not possible and also a direct transmission of certain media is excluded in connected heating systems, the primary energy sources are summarized in heat supply systems in a so-called heat sink and in this a heat exchange of the primary media in a secondary medium. To compensate for strongly varying amounts of heat, a larger volume of liquid is provided on the secondary side.

The above-described objects has to provide a heat exchanger as a central element.

This task can be solved with a highly effective plate heat exchanger. However, these have considerable disadvantages due to their design in heat supply systems. Thus, in areas with a large amount of drinking water, there is a need to spread the operating media of the heat supply system using chemical-physical methods. Ultimately, this is also necessary with only small refills.

If no treatment of the medium takes place, the heat exchanger sets in within a short period of time and loses considerably in terms of efficiency, throughput and dynamics.

For plate heat exchangers, the calcification in the section serving the service water supply, which is constantly filled with fresh water, is unavoidable. A dry cleaning added plate heat exchanger ultimately leads to material damage and thus to a shortened life of the same. For the above reasons, plate heat exchangers are rarely used in heat supply systems.

In order to avoid the problems described in plate heat exchangers, in heat supply systems so-called combined storage with a large container and a pipe arranged therein run. These have a comparatively large storage volume with a small separator area of the heat exchanger at the same time. Due to the inevitable in the combination storage thermal coatings results in these a temperature gradient from top to bottom.

If the equilibrium is disturbed by removal of heat in such a combination storage, this naturally takes place via removal possibilities arranged at the top in the combination storage tank, as a result of which significant cooling occurs in the upper area of the combination storage tank. The cooled medium begins to move downwards and mixes with colder layers, eventually creating a mixing temperature that may not allow for heat removal.

In some combi storages, a torus consisting of cold water forms, which permanently disturbs the temperature conditions within the combi store when it sinks.

This disadvantageous effect is attempted to be avoided by various manufacturers of such combi storage by the installation of transverse bulkheads and overflow into the combi storage. Thus, in a known system CTC Eco Zenith I 550 CTC AB, 341 26 Ljungby, Sweden, installed in such a combi storage a transverse bulkhead, which is provided in each case with a multi-hole overflow channel both in the upper and in the lower area.

In the spiro combination storage of the company FEURON AG, 9430 St. Margrethen, Switzerland, in turn with a distributed over the entire volume of the combined storage spiral heat exchanger tries to maintain a stratification of the medium according to the natural temperature layers as long as possible.

In both combi stores described above, the medium usually supplied with the highest temperature of a solar thermal collector is supplied with its own heat exchanger within the combination storage and the same arranged in both cases on the container bottom. In the combined storage tank of the CTC Eco Zenith I 550 system, the heat exchange takes place with the cold medium present in the lower chamber, while in the Spiro combi tank from FEURON AG, a narrow spiral wound heat exchanger is additionally enclosed in a separate housing and the rise is preferred with a riser channel of the heated medium should take place in the upper region of the combination storage.

Both systems have the disadvantage that they work with large volumes and have a complicated internal structure. The inevitably resulting temperature stratification and the technical precautions to prevent unwanted mixing processes make the combi storage devices at the same time sluggish in their behavior. The technical effort and thus the production costs are high.

However, to ensure heat exchange with low inertia, it is essential to ensure highly efficient heat exchange.

In the Spiro combi tank from FEURON AG, a coil is provided for this, which is designed in corrugated pipe and according to the technical description of this combi storage inside the corrugated pipe to generate a turbulent flow for effective heat exchange. However, an effective heat exchange can not be achieved because the medium surrounding the corrugated tube has no turbulent flow and special precautions to achieve this flow form are not available.

Therefore, there is a need to replace the combination storage by heat exchangers, which allow the exchange of amounts of heat between a primary and a secondary medium with significantly reduced inertia, while avoiding the existing in the plate heat exchangers described above susceptibility. Previously known conditions of use with their different temperature ranges must be taken into account as well.

It is therefore an object of the invention to provide a heat storage, which transfers the amount of heat without great inertia of an incoming also in the heat exchanger secondary medium of incoming media from primary circuits and thus allows a quick response to changing heat demand, is durable and also built simple and inexpensive can reduce the total cost of heating systems or heat supply systems and, moreover, improve the degree of thermal efficiency of such installations.

In the following description, embodiments and claims, the following terms are used with the following meaning:
Heat exchanger - is a tube heat exchanger with at least one arranged in a container tube coil and outwardly guided connections for the coil and the container interior.

Coil - is a helical and / or spiral wound pipe whose pitch may be uniform or different in different areas.

Tube - is a metallic tube with a profiled wall, preferably a corrugated tube with a parallel or a helical corrugation.

Separator - is a solid and liquid impermeable partition between different media. It is formed by the pipe wall.

Medium - is a fluid that can contain and transport heat.

First medium - is a fluid that can be heated by any heat sources and in a heat exchanger transfers these amounts of heat to a second medium.

Second medium - is a fluid that takes in a heat exchanger from the first medium amounts of heat and these existing in the system Consumers or transported to storage units.

The above object is achieved with a heat exchanger having the features of the characterizing part of claim 1 in conjunction with the features of the preamble of this claim. Secondary and subordinate claims describe embodiments of the heat exchanger according to the invention.

According to the invention, the object is achieved with a heat exchanger in the design of a tubular heat exchanger. This is designed so that its container volume is filled with the first medium and a second medium flows through a likewise arranged in the container tube coil.

This ensures that always a sufficiently large amount of heated first medium is present and the amount of heat transporting away second medium can take over these amounts of heat as needed and in a short time and with a large flow.

The heat exchanger achieves a conversion efficiency of at least 90 percent, based on the amounts of heat supplied to the first medium and those discharged with the second medium, under the temperature conditions existing in heat supply systems.

• – Es wird ein Verhältnis der Volumina des Behälters und des Volumens der Rohrschlange angestrebt, das bei einem Wert von 5 oder darunter liegt.
• – Der Behälter des Wärmetauschers ist stark wärmegedämmt.
• – Die Rohrschlange besteht aus einem metallischen Werkstoff.
• – Die Wandstärke des Rohres der Rohrschlange ist sehr gering.
• – Die Rohrschlange ist in begrenztem Umfang im Behälter beweglich.
• – Die Behälterform ist so gewählt, dass eine geringe Oberfläche des Behälters vorhanden ist.

To achieve this, the heat exchanger has at least the following parameters:

• The aim is a ratio of the volumes of the container and the volume of the coil, which is at a value of 5 or less.
• - The container of the heat exchanger is very thermally insulated.
• - The coil is made of a metallic material.
• - The wall thickness of the tube of the coil is very low.
• - The coil is movable to a limited extent in the container.
• - The container shape is chosen so that a small surface of the container is present.

With the measures described above, the invention achieves that the container of the heat exchanger is always filled with a sufficient amount of heated first medium. If a heat requirement arises, the second medium flows through the coil and there is an intense heat exchange.

Particularly preferred in this case is a tube coil, which consists of a thin-walled corrugated tube. Such type corrugated pipes have wall thicknesses in the range of a few tenths of a millimeter. The pipe wall thus forms an extremely thin separator, through which an intensive heat transfer can be achieved.

According to the invention stainless steel corrugated pipes are used for the coil. The reduced heat transfer in stainless steels is compensated by the small wall thickness.

The helically wound coil of a corrugated tube causes the transition to a turbulent flow even at a comparatively low flow velocity, whereby the exchange process is intensified to a considerable extent.

The coil can move in the container to a limited extent, for example as a result of thermal expansion. As a result, and due to the predominantly turbulent flows, no deposits can form in the area of the separator.

The container of the heat exchanger preferably has a cylindrical shape. Its length can be up to 6 times the diameter.

On the other hand, the comparatively small container volume causes the first medium to be constantly fed again and therefore also has a high flow velocity in the container. Thus, a largely turbulent flow also occurs on this side of the separator and the exchange process is additionally intensified.

The measures described above prevent a layering of the first medium after the temperature inside the container. Tori in the first and temperature fluctuations in the second medium are thus largely prevented.

The heat exchanger according to the invention can thus with a comparatively small volume of about 60 l, an inlet temperature of the first medium of about 90 ° C, a flow rate of the first and second medium of about 3000 l / h and a temperature gradient of about 40 ° C a specific Achieve output of 750 W per 100 cm ² separator area.

Thus, the performance parameters of the heat exchangers according to the invention reach those of plate heat exchangers.

It is also possible to carry out the heat exchanger according to the invention so that the coil is fanned in the container interior to a multiple arrangement. This allows the volume ratios between the first and second Influence medium in the heat exchanger in favor of the second medium. The plurality of pipe coils can either be guided with their individual ports to the outside and connected outside the container or branched within the container.

In the event that more than one tube coil are arranged in the container and their connections are led to the outside, one of the tube coils can also be connected to a further heat source.

Likewise, one of the coils may be connected to a circuit of a heat supply system which requires a different temperature level.

A preferred embodiment is that at least one second coil serves to connect a third medium from a heat source or from a heat consumer to the heat exchanger when the third medium may not be mixed with the first or the second medium due to special properties.

Depending on the specific embodiment of a heat supply system in which the heat exchanger according to the invention is used, it may be provided with a coil for the service water supply, so that the provision of hot water can be made possible in this way.

Also, depending on the configuration of a heat supply system in which the heat exchanger according to the invention is used, it may be provided with an electrically operated heating cartridge, which can take over either a supply of heat or only the assurance of frost protection.

Due to the profiled wall of the coil, on the one hand, the surface serving for heat exchange increases, hence the so-called separator surface. Furthermore, the second medium to be heated in the coil undergoes a turbulent flow through the profiled wall, which intensifies the heat exchange.

According to the invention, the heat exchanger is designed so that it has the lowest possible inertia in heat transfer based on the heat demand in the heating circuit. To achieve this, the heat exchanger is designed to have a conversion efficiency of at least 90 percent.

The invention will be explained in more detail below with reference to some embodiments and drawings. Showing:

1 - A schematic representation of the heat exchanger according to the invention.

2 - An embodiment of the heat exchanger according to the invention, in which all the coils are connected in parallel.

3 - An embodiment of the heat exchanger according to the invention, in which all the coils are connected in parallel within the heat exchanger.

The heat exchanger according to the invention 1 consists of at least one container 2 , one the container 2 surrounding insulation 3 and a coil 4 ,

Contrary to the embodiment known from the prior art heat exchanger for heating systems or heat supply systems is provided by heat generators heated first medium in the interior 7 of the container 2 existing and a heat consumer supplying second medium, which is heated by exchange processes, flows through the coil 4 ,

The pipe coil 4 is with their outgoing connections 5 and 6 connected to a line circuit in which heat consumers are located. In the interior 7 of the container 2 is the first medium, the container 2 over the connections 8th and 9 is connected to the first line circuit, are arranged in the heat generator. Heat generators can be thermal solar collectors, heat pumps, boilers, geothermal probes or facilities that recover process heat.

In the heat exchanger according to the invention 1 can a second pipe coil 10 and a third pipe coil 11 be arranged, these with their connections 12 and 13 such as 14 and 15 can also be associated with heat consumers.

The pipe snakes 4 . 10 and 11 can be connected to one and the same circuit. You can also feed different circuits with a heated medium.

In the simplest case, there is only one pipe coil 4 in the heat exchanger 1 arranged.

• – Das Verhältnis zwischen dem ersten Medium im Innenraum 7 des Behälters 2 und dem zweiten Medium in der Rohrschlange 4 bewegt sich zwischen 1:2 bis 1:4. Für einen Wärmetauscher 1 mit einem Inhalt von 60 l bedeutet das, dass bis zu 24 l des zweiten Mediums in der Rohrschlange 4 enthalten sein können.
• – Der Wärmetauscher 1 hat bei einem Volumenstrom von Q₁ = 1000 l/h, einer Eingangstemperatur von 60°C und einer Ausgangstemperatur von 40°C eine Leistung von 24 kW.
• – In dem beschriebenen Fall beträgt die Übertragungsleistung des Separators/der Separatorwand 125 W/100 cm².
• – Der Wärmetauscher 1 hat bei einem Volumenstrom von 470 l/h, einer Eingangstemperatur von 50°C und einer Ausgangstemperatur von 10°C eine Leistung von etwa 23 kW.
• – Die spezifische Leistung des Separators kann dann 150 W/100 cm² betragen.
• – Der Wärmetauscher 1 erreicht nach dem Aufheizen Eigenschaften, die denen eines Plattenwärmetauschers entsprechen. Lediglich beim Aufheizzyklus ist die sich aus den Volumenströmen am Ein- und Ausgang des Wärmetauschers 1 ergebende Trägheit vorhanden.
• – Nach erfolgtem Aufheizen kann unter gleichen Bedingungen für eine beliebig lange Zeit ein Volumen von etwa 500 l aufgeheiztes zweites Medium mit einer Temperatur von 50°C entnommen werden.
• – Der Wärmetauscher 1 hat eine rechnerisch ermittelte Spitzenleistung von 120 kW, bezogen auf einen Durchfluss von 3000 l/h. Er kann bei einem Stocken der Zufuhr von erwärmtem ersten Medium für eine Zeit von etwa 1 min den Austauschprozess mit einer Leistung von etwa 100 kW aufrechterhalten.
• - Der Wärmetauscher 1 hat bei einem erhöhten Durchfluss von 3000 l/h, bei einer Eingangstemperatur von 90°C, einer Ausgangstemperatur von 50°C am Separator/der Separatorwand eine spezifische Leistung von 750 W/100 cm².

Such an arrangement has the following advantages when a heat exchanger 1 based on a volume of 60 l:

• - The ratio between the first medium in the interior 7 of the container 2 and the second medium in the coil 4 ranges from 1: 2 to 1: 4. For a heat exchanger 1 with a content of 60 l that means that up to 24 l of the second medium in the coil 4 may be included.
• - The heat exchanger 1 has a capacity of 24 kW at a flow rate of Q ₁ = 1000 l / h, an inlet temperature of 60 ° C and an outlet temperature of 40 ° C.
• In the described case, the transfer performance of the separator / separator wall is 125 W / 100 cm ² .
• - The heat exchanger 1 has a capacity of approximately 23 kW at a flow rate of 470 l / h, an inlet temperature of 50 ° C and an outlet temperature of 10 ° C.
• The specific power of the separator can then be 150 W / 100 cm ² .
• - The heat exchanger 1 achieved after heating properties that correspond to those of a plate heat exchanger. Only during the heating cycle is the volume flow at the inlet and outlet of the heat exchanger 1 resulting inertia present.
• After the heating has taken place, a volume of about 500 l of heated second medium with a temperature of 50 ° C. can be removed under the same conditions for an arbitrarily long time.
• - The heat exchanger 1 has a calculated peak power of 120 kW, based on a flow rate of 3000 l / h. It can maintain the exchange process with a power of about 100 kW when the supply of heated first medium is stopped for a time of about 1 minute.
• - The heat exchanger 1 has a specific power of 750 W / 100 cm ² at an increased flow of 3000 l / h, with an inlet temperature of 90 ° C, an outlet temperature of 50 ° C at the separator / separator wall.

• – Die übertragene Leistung ist direkt proportional zur Fläche des Separators, mithin zur Fläche der eingesetzten Wellrohrschlange und letztlich auch zur Anzahl der Wellrohrschlangen. Ebenso verhält sich die übertragene Leistung direkt proportional zum Volumenstrom auf der Primär- und der Sekundärseite sowie zum Temperaturgradienten ∆t.
• – Die Rohrschlange 4 besteht aus einem Edelstahlwellrohr.
• – Das Edelstahlwellrohr ist parallel oder schraubenförmig profiliert.
• – Die Wanddicke des Edelstahlwellrohrs liegt zwischen 0,1 mm und 0,5 mm. Damit wird durch die geringe Wanddicke der an sich ungünstigere Wärmeübergang bei Edelstählen gegenüber unedlen Stählen weitgehend unterdrückt.
• – Die Rohrschlange 4 ist im Innenraum 7 des Behälters 2 begrenzt beweglich aufgehängt. Sie kann sich aufgrund von Temperaturänderungen ausdehnen und/oder ihre Form geringfügig ändern.
• – Die Strömung in der Rohrschlange ist durch die Verwendung von Wellrohren bereits bei geringen Strömungsgeschwindigkeiten turbulent und sichert damit einen intensiven Austauschprozess.
• – Die Volumenverhältnisse und die geometrische Gestaltung der Rohrschlange 4 sind so gewählt, dass auch im Innenraum 7 des Behälters 2 eine turbulente Strömung herrscht und damit der Austauschprozess auf beiden Seiten des Separators gleich intensiv abläuft.
• – Durch die Wahl einer Rohrschlange 4 aus Edelstahl-Wellrohr in Verbindung mit ihren Formveränderungen und den turbulenten Strömungen werden Ablagerungen auf dem Separator vermieden und der Austauschprozess kann dabei über lange Zeit mit gleicher Intensität erhalten bleiben.
• – Durch die gewählten Volumenverhältnisse zwischen Innenraum 7 und Rohrschlange 4 und durch die Form derselben können im Innenraum keine temperaturabhängigen Schichtungen des ersten Mediums entstehen.

Regardless of the actual size of the heat exchanger according to the invention 1 continues to apply:

• - The transmitted power is directly proportional to the area of the separator, thus to the area of the corrugated pipe used and ultimately to the number of corrugated pipe coils. Likewise, the transmitted power behaves directly proportional to the volume flow on the primary and the secondary side and to the temperature gradient .DELTA.t.
• - The pipe coil 4 consists of a stainless steel corrugated pipe.
• - The stainless steel corrugated tube is profiled in parallel or helical.
• - The wall thickness of the stainless steel corrugated pipe is between 0.1 mm and 0.5 mm. This is largely suppressed by the small wall thickness of the less favorable heat transfer in stainless steels compared to non-noble steels.
• - The pipe coil 4 is in the interior 7 of the container 2 limited moveable suspended. It may expand due to temperature changes and / or change shape slightly.
• - The flow in the coil is by the use of corrugated pipes even at low flow rates turbulent and thus ensures an intensive exchange process.
• - The volume ratios and the geometric design of the coil 4 are chosen so that even in the interior 7 of the container 2 a turbulent flow prevails and thus the exchange process takes place on both sides of the separator with equal intensity.
• - By choosing a pipe coil 4 Made of stainless steel corrugated pipe in conjunction with their shape changes and the turbulent flows, deposits on the separator are avoided and the replacement process can be maintained over the long term with the same intensity.
• - By the selected volume ratios between the interior 7 and pipe coil 4 and due to the shape of the same, no temperature-dependent stratifications of the first medium can arise in the interior.

This ensures that the heat exchanger 1 realizes an exchange process designed for the maximum achievable maximum in each operating state and achieves in each case a more than 90% efficiency.

The effectively conducted exchange process also causes a target temperature of 50 ° C in the second medium to be reached in one-tenth of the time required by a combi store known in the art.

The extremely low inertia of the heat exchanger 1 is achieved in addition to the measures already mentioned above, that with the coil 4 Separator surface has a value between 150 cm ² -700 cm ² per liter of container volume has.

The achievement of such a high value can also be made possible by the fact that more coils 10 and 11 in the container 2 are arranged.

The pipe snakes 4 . 10 and 11 may be designed as helical coils, as helical coils or as a combination of both forms.

Special embodiments of the heat exchanger according to the invention 1 can arise because of the coils 4 . 10 and 11 with a connection line 16 outside the insulation 3 are connected.

It is also possible the connection 16 only between two of the existing coils 4 . 10 and 11 while the remaining coil is associated with a separate circuit. This is, for example, the preferred variant if, in addition to the heating or heat supply system, a process water treatment must take place.

The interconnection of the pipe coils 4 . 10 and 11 also in the interior 7 of the container 2 with a connection 17 be executed. In this case, the interconnection is in from the insulation 3 enclosed area takes place and there are only the connections of the coil 4 led through the insulation to the outside. This creates an effective heat exchanger with a large separator surface.

Ultimately, such a heat exchanger according to the invention forms the possibility of designing various embodiments in the manner of a modular system and thus of adapting it to specific conditions of use.

The arrangement described above can be carried out by known means as a standing or as a hanging arrangement or as a combination of both possibilities

It is also possible to carry out the heat exchanger according to the invention in prefabricated form with the necessary line connections and optionally combined with valves and circulating pumps.

The insulation 3 of the heat exchanger 1 can be designed according to the criteria of optimal energy utilization. It may further include conduits, valves and circulation pumps. Likewise, it can be designed removable.

Thus, the invention has the advantage of proposing heat exchangers for heating or heat supply systems which operate efficiently, whose dimensions are small, which provide low inertia heated media, and otherwise can be produced inexpensively and with low material and manufacturing expense.

LIST OF REFERENCE NUMBERS

1

 heat exchangers

2

 container

3

 insulation

4

 coil

5

 connection

6

 connection

7

 inner space

8th

 connection

9

 connection

10

 coil

11

 coil

12

 connection

13

 connection

14

 connection

15

 connection

16

 connection

17

 connection

Claims (10)

Heat exchanger ( 1 ) for a heating system or a heat supply system consisting of a tubular heat exchanger with a closed container ( 2 ) and one in the container ( 2 ) arranged spirally or helically wound coil ( 4 ), from a corrugated tube or a corrugated tube and a container ( 2 ) enclosing insulation ( 3 ), characterized in that a first heat-carrying medium the interior ( 7 ) of the container ( 2 ) and the coil ( 4 ) contains a second heat-carrying medium. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 1, characterized in that the volume of the first medium in the interior ( 7 ) of the container ( 2 ) at most 6 times the volume of the second medium in the coil ( 4 ) is. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 1, characterized in that it has a volume of about 60 l and at a flow rate of the first and the second medium of about 600 l / min of an inlet temperature of the first medium of 80 ° C, an inlet temperature of the second medium of 10 ° C, an outlet temperature of 50 ° C of the second medium, thus a temperature gradient .DELTA.t = 40 ° C in the second medium has a power of 30 kW. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 1, characterized in that the same at a volume of about 60 l a short term achievable peak power of about 100 kW or a theoretical peak power of about 120 kW, based on a flow of 3000 liters per hour in second medium has. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 4, characterized in that the same at a flow rate of about 3000 l / h of each of the first and second medium, an inlet temperature of 90 ° C of the first and an outlet temperature of 50 ° C of the second medium, thus at a temperature gradient .DELTA.t = 40 ° C between the two media, a Conversion degree of the separator of 750 W / 100 cm ^{2 is} reached. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 1, characterized in that the heat exchanger is designed so that it has a Separatorfläche of at least 150 cm ² based on a liter of container contents. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 1, characterized in that the coil is divided into multiple strands and at least one outer and one inner coil are arranged coaxially with each other. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 1, characterized in that in the container at least one further tube coil is arranged, which is connected to an independent line circuit, which leads to a third medium. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 1, characterized in that the guided in the further coil third medium is guided in an open circuit. Heat exchanger ( 1 ) for a heating system or a heat supply system according to claim 10, characterized in that the third medium the heat exchanger amounts of heat and / or dissipates.

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