Thermal installation for time-critical buildings

Abstract

A thermal system 1 with a double-circuit thermal system is provided, comprising a primary circuit 2.1 for heat generation and distribution and a secondary circuit 2.2 for heat transfer. Both circuits 2.1 and 2.2 are hydraulically decoupled but thermally combined by means of the heat exchanger 5. The thermal system 1 according to the invention enables the continued use of existing heating systems in existing buildings and their operation using a low-exergy heat source, in particular a heat pump 3, based on a low-temperature level. The reduced heating output is supplemented by the ceiling radiant heating system 4, which is additionally provided as a secondary circuit.

Description

[0001] The invention relates to a thermal engineering system for time-critical buildings.

[0002] Older buildings, in particular, often have heating or cooling systems that are inefficient, meaning they require more energy for each task than modern systems. This makes energy savings through new heating or cooling systems essential. When undertaking energy-efficient renovations of such buildings, such as schools, offices, or apartments, the current standard practice is to completely remove the old heating systems and replace them with new ones. This is not only costly and resource-intensive, but it also frequently requires lengthy construction work, during which the buildings are unusable for an extended period.The term "time-critical buildings" refers to buildings for which heating system modifications require only a short period of time, so that – as in the case of schools – the modifications can be started and completed during the school holidays and a change in the schedule of lessons, for example, is not necessary.

[0003] Another aspect of energy-efficient renovation is the current focus on modern energy systems, including heat pumps. A disadvantage of heat pumps is that the achievable flow temperature is too low to adequately heat classrooms in schools, for example, using existing heating systems such as conventional radiators, to maintain comfortable temperatures. Therefore, such systems often require a boiler in addition to the heat pump, and all old radiators, which operate at significantly higher flow temperatures, must be replaced with more modern radiators or heat exchangers, such as plate heat exchangers. However, as previously described, this involves relatively lengthy conversion work, as all components of such a heating system must be replaced. That is to say...In addition to the radiators, all valves and pipes must also be replaced. For time-critical buildings, such a procedure, or this type of renovation or conversion, is extremely disadvantageous and does not meet the criteria for time-critical buildings.

[0004] These demands create a conflict: while energy-efficient renovations involving the installation of new, modern heating and cooling systems require the removal of the old systems, this is associated with high costs and relatively lengthy conversion work, making it unsuitable for time-critical buildings because the old heating and cooling systems cannot be reused. In addition to the high costs, such a conversion is by no means resource-efficient and consumes time that is often unavailable for building retrofits.

[0005] The object of the present invention is to create a thermal engineering system for heating and / or cooling buildings or rooms in which conventionally installed heating and / or cooling elements, including the connecting pipes, can continue to be operated in a resource-saving manner with a heat transfer medium at a low temperature level without having to replace them, but which nevertheless allows room temperatures in the comfort range to be achieved and which enables a conversion to energy-saving heating or cooling systems applicable to time-critical buildings.

[0006] This problem is solved by a thermal engineering system with the features according to claim 1. Advantageous further developments are defined in the dependent claims.

[0007] A thermal system according to the present invention is equipped with a dual-circuit thermal system. It comprises a primary circuit, which is designed as a heat distribution and heat generation circuit, and a secondary circuit, which is designed as a heat transfer circuit. Both circuits are combined by means of a heat exchanger but are hydraulically decoupled from each other. The primary circuit thus represents a first thermal circuit and the secondary circuit a second thermal circuit. If a conventional heating system is modified such that the boiler provided for this purpose is replaced by a heat source operating in the low exergy range, preferably a heat pump, then a first heat transfer medium is circulated in the primary circuit through heating or cooling elements by the heat pump using appropriate pumps and control elements.A disadvantage of such conversions of boilers to these heat sources, preferably heat pumps, is the lower flow temperatures that can be achieved. These are generally insufficient to reach a temperature level within the comfort zone in the rooms or buildings to be heated using conventional radiators. For this reason, and this is precisely where the invention comes in, a second heating system forming the secondary circuit, which can also be operated as a cooling system, is installed, preferably in the form of a radiant ceiling heating system on the ceiling of the room or building to be heated. This radiant ceiling heating system has a separate circuit, namely the second thermal circuit, in which a second heat transfer medium circulates via pumps and corresponding control devices.The double-circuit system formed from the primary and secondary circuits is connected via the heat exchanger in such a way that the thermal energy transferred from the primary circuit to the radiators by means of the first heat transfer medium circulating therein is transferred to the second heat transfer medium circulating in the ceiling radiant heating circuit, which is hydraulically decoupled from the primary circuit. This allows sufficient radiant heat to be introduced into the room to be heated by means of the ceiling radiant heating system to supplement the missing portion from the existing thermal circuit. Thus, the combination of ceiling radiant heating and the existing heating system, including the pipes and radiators, provides adequate heating.The heat exchanger is now configured so that the two circuits, and thus the heat transfer fluids circulating within them, are hydraulically decoupled, yet combined via the heat exchanger. This allows all existing heating systems to be retained and used despite the significantly lower flow temperature required by the low-exergy heat source; they do not need to be removed during a renovation. By additionally installing radiant ceiling heating, the heating energy that the old heating system cannot supply when replacing the boiler with a low-exergy heat source can be added.

[0008] Preferably, both the secondary circuit, designed as a ceiling heating or cooling circuit, and the primary circuit, designed as a low-exergy heat source circuit, are operated at low temperatures. This means that the flow temperatures, for example, are not higher than 40°C. In conventional heating systems with a boiler, the flow temperatures are significantly higher, at least by 10 to 20 K. The heat transfer fluids present in the respective circuits according to the invention are circulated within them by means of appropriate pumps and control devices, so that the heating energy obtained from the low-exergy heat source, preferably the heat pump, is used to charge the first heat transfer fluid in the primary circuit.The energy at this low temperature level is then hydraulically decoupled in the heat exchanger and transferred to the secondary circuit, designed as a ceiling radiant heating circuit, to operate the ceiling radiant heating system, which can also be used for cooling.

[0009] Preferably, temperature control valves are provided in both circuits, in particular a 3-way valve in the secondary circuit, preferably in a purely mechanical design, by means of which precise control of the temperature of the heat transfer fluid in the respective circuits is achieved in conjunction with volume flow control devices. Using these control devices, it is possible to adjust the temperature to be achieved in the rooms or buildings to the comfort range, depending on the prevailing outside temperature.

[0010] Preferably, this control between the two heat transfer fluids of the two thermal circuits is regulated such that the flow temperature in the primary circuit has a maximum temperature level such that the flow temperature for the secondary circuit, preferably designed as a ceiling radiant heating system, is at least 35°C. This ensures that, despite the low temperature level of preferably 35°C, the ceiling radiant heating system delivers the portion of heating energy into the room to be heated that can no longer be provided by the old heating system, which, after the installation of a low-exergy heat source, preferably a heat pump, replaces the original boiler. A ceiling radiant heating system is capable of providing sufficient heat even with this relatively low flow temperature level of approximately 35°C.Operating at 35°C is effective because the principle of radiant energy transfer functions according to the physical law that the transferred radiant energy is proportional to the fourth power of the temperature. As a precautionary measure, weather-compensated adjustment of the flow temperature in the primary circuit is always recommended.

[0011] Since the primary circuit, i.e. the so-called heat pump circuit, which is formed by the individual heating or cooling elements and the pipes connecting them, corresponds to the old heating system, except that the old boiler is replaced by a low-exergy heat source, the energy-efficient renovation can continue to be used with the originally existing heating or cooling elements and the old existing pipes in a resource-saving and time-saving manner.

[0012] Preferably, the thermal system in the ceiling radiant heating system incorporates sound-insulating perforated radiant surface elements. This makes the already effective ceiling radiant heating system particularly suitable for rooms where sound insulation is important, such as classrooms, especially during breaks. Furthermore, the ceiling radiant heating systems are preferably equipped with integrated lighting elements, eliminating the need for separate lighting elements in rooms requiring energy-efficient renovation or optimization in time-critical buildings.The primary circuit is therefore preferably already fully integrated into the existing building, except for the low-exergy heat source that replaces the boiler. The ceiling radiant heating system can also be operated for cooling without full thermal insulation and can be installed in the room to be heated or cooled. The primary and secondary circuits are combined via the heat exchanger. The key advantage of the invention lies precisely in the fact that the ceiling radiant heating elements of the secondary circuit are combined with the elements of conventional heating systems, in which heat pumps are preferably used instead of the usual boiler, so that the advantages of both known elements can be utilized in combination. This results in the aforementioned advantages and effects. Such a novel system is resource-efficient, i.e.,a novel thermal engineering system, precisely because existing components are used and, through another essential component, namely the secondary circuit preferably in the form of a ceiling radiant heating system, the energy deficits of the old, modified system can be combined with the energy advantages of an additional heating system.

[0013] Preferably, both circuits are equipped with controls for the temperature and mass flow rate of the respective heat transfer medium, so that the room to be thermally treated can be adjusted to the desired comfort temperature under changing outdoor conditions.

[0014] Further advantages and details are now described below in the following exemplary embodiment according to the figure.

[0015] Figure: Double circuit system of a heat engineering plant according to the invention.

[0016] The figure shows the heat transfer system 1 according to the invention, which has a double circuit system in which a heat pump circuit and a secondary circuit 2.2 or primary circuit 21 or a ceiling radiant heating circuit are combined by means of a heat exchanger 5, but are hydraulically decoupled from each other. The heat pump circuit 2.1, which is filled with a first heat transfer medium, runs from the heat pump 3 to the heat exchanger 5 and from there via a temperature controller 8.1 to a radiator or cooling element 6 and from there via the pipe 9 back to the heat pump 3.

[0017] The primary circuit, or heat pump circuit 2.1, has a heat pump 3 in place of the originally existing boiler 12. The first heat transfer fluid circulating in the heat pump circuit 2.1 is conveyed from the heat pump 3 to the heat exchanger 5 by means of a pump (not shown). The figure shows the double-circuit system, consisting of the heat pump circuit 2.1 and the ceiling radiant heating circuit 2.2, and, according to the invention, their thermal coupling is realized via the heat exchanger 5. However, hydraulic decoupling takes place in the heat exchanger 5. By means of the thermal coupling, the flow temperature from the heat pump 3 in the heat exchanger 5 is raised to such a level that the flow temperature in the ceiling radiant heating circuit 2.2, i.e., the secondary circuit, does not exceed a temperature of approximately 40°C, at which the second heat transfer fluid of the ceiling radiant heating circuit 2.2 is heated.2 is directed into the ceiling radiant heating system 4 and returned to the heat exchanger 5 via the return line.

[0018] The ceiling radiant heating system 4 features sound-absorbing, perforated radiant surface elements 10, which are particularly advantageous when there is noise in the rooms to be heated that needs to be absorbed. This is necessary, for example, in school classrooms. The ceiling radiant heating system 4 also has integrated lighting elements. Therefore, if the ceiling of the room to be heated is covered with a multi-element ceiling radiant heating system 4, no additional lamps need to be installed, as the lighting elements 11 are designed to provide sufficient illumination of the room.

[0019] The combination of the two circuits 2.1 and 2.2 ensures that existing heating installations consisting of radiators 6 and corresponding piping systems 9, as well as control elements 8.1, 8.2, can be used for the new system according to the invention without having to be dismantled. Replacing the originally intended boiler 12 with a heat pump 3 means that the circulating first heat transfer fluid can only be heated in the low-temperature range, which is insufficient for heating the room to a comfortable temperature. A ceiling radiant heater 4 is now additionally connected via the heat exchanger 5, thus combining two heating circuit systems, so that the missing heating output of the heat pump circuit is compensated for by the additional heating output of the ceiling radiant heater 4.The combination of both circuits thus leads to a dual-circuit system which can use old heating installations and still ensures sufficient heating in the room to be tempered, making it possible to convert time-critical rooms to a new, energy-efficient, ecological heating system with significantly reduced conversion effort. Reference symbol list

[0020] 1. Heating system 2.1 Heat pump circuit / primary circuit 2.2 Ceiling radiant heating circuit / secondary circuit 3. Heat pump 4. Ceiling radiant heating 5. Heat exchanger 6. Radiator 7. Pump 8.1 Temperature controller primary circuit 8.2 Temperature controller secondary circuit 9. Piping 10. Sound-absorbing perforated radiant surface elements 11. Lighting elements 12. Boiler

Claims

1. Thermal system (1) with a thermal double circuit system in which a heat generation and heat distribution circuit designed as a primary circuit (2.1) and a secondary circuit designed as a heat transfer circuit (2.2) are hydraulically decoupled by means of a heat exchanger (5) and thermally combined with each other via respective heat transfer media.

2. Thermal engineering system (1) according to claim 1, in which the primary circuit (2.1) is designed as a circuit with a low-exergy heat source, in particular a heat pump (3), and the secondary circuit is designed as a ceiling radiant heating or ceiling radiant cooling circuit and is operated at a low temperature level and is circulated by respective heat transfer fluids by means of pumps (7), wherein the low-exergy heat source energetically charges the heat transfer fluid in the primary circuit (2.1).

3. Thermal engineering system (1) according to claim 1 or 2, in which the primary circuit (2.1) comprises heating or cooling elements (6) which are connected to each other by means of pipes 9.

4. Heat engineering system (1) according to one of claims 1 to 3, in which at least one temperature control valve (8.1, 8.2), in particular a 3-way valve, is provided in the secondary circuit (2.1, 2.2).

5. Thermal system (1) according to one of claims 2 to 4, in which the heat transfer medium of the primary circuit (2.1) provided with the low-exergy heat source has a heat source supply temperature with such a maximum temperature level that the supply temperature of the ceiling radiant heating (4) is at most 40°C.

6. Thermal system (1) according to one of claims 2 to 5, wherein the low-exergy heat source is a heat pump (3) or a colder heat network (3) of the primary circuit (2.1) replaces a boiler (12) or a classic heat network with higher heat transfer fluid temperatures.

7. Thermal engineering system (1) according to one of claims 2 to 6, in which the ceiling radiant heating system (4) has sound-insulating perforated radiant surface elements (10).

8. Thermal system (1) according to one of claims 2 to 6, in which the ceiling radiant heating system (4) has integrated lighting elements (11).

9. Thermal system (1) according to one of claims 2 to 8, in which the primary circuit (2.1) is integrated in an existing building and the ceiling radiant heating (4) can also be operated as cooling without full thermal insulation and is arranged in addition to the primary circuit integrated in the existing building, which forms an existing heating system.

10. Thermal engineering system (1), according to one of claims 1 to 9, in which the temperature of a space to be thermally treated is controlled by mass flow and / or temperature control of the heat transfer medium.

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