Flow component for a hybrid heating system

Abstract

The invention relates to a flow component for a hybrid heating system, wherein the flow component comprises a housing with a recess, a first inlet portion for inletting liquid coming from a heating appliance of the hybrid heating system to the recess, a first release portion for release liquid from the recess to the heating appliance, a second inlet portion for inletting liquid coming from a further heating appliance of the hybrid heating system to the recess, a second release portion for release liquid from the recess to the further heating appliance and a separating device that is selectively arrangeable in a first position or in a second position, wherein in the first position the separating device is at least partly arranged in the recess and separates the first inlet portion from the first release portion and in the second position the separating device is arranged such that a fluid communication exists between the first inlet portion and the first release portion.

Description

[0001] The invention relates to a flow component for a hybrid heating system. Additionally, the invention relates to a heating appliance with such a flow component. Further, the invention relates to a hybrid heating system having a heating appliance and a further heating appliance. Additionally, the invention relates to the use of such a flow component to retrofit a heating appliance to a hybrid heating appliance or vice versa.

[0002] Several different types of heating appliances for heating houses and / or a buildings are known. Specifically, it is known to use one or more heating appliances for a load circuit that can comprise a central heating circuit and / or a domestic water heating circuit. A market demand exists for hybrid heating systems which comprise several heating appliances of different types. Specifically, there exists a market demand for heating appliances that can be retrofitted to be used later in a hybrid heating system. The heating appliance to be retrofitted is in particular a boiler, in particular a gas boiler, and in particular a heat pump is connected to the boiler to form the hybrid heating system.

[0003] One reason for such market demand is that the price for the hybrid heating system is high so that the user want to split the investment by buying first the heating appliance, which is in particular a boiler, and later the further heating appliance, which is in particular a heat pump,. Another reason is that the user wants to have the option to decide about the type of the further heating appliance after the heating appliance, in particular comprising a combustion appliance, is installed.

[0004] Usually, the known heating appliances cannot be retrofitted to be used in a hybrid heating system or significant installation efforts are needed to retrofit said heating appliances to be used in a hybrid heating system. This results as a known heating appliance is a complete solution which does not allow for a constructively easy adaption and optimization of its components. Additionally, retrofitting of the heating appliance to be used in a hybrid heating system is difficult in a limited and poorly accessible installation space. This means that an installer, who needs to install the heat pump has to work at least partially behind the boiler parts, which leads to longer retrofitting times and reduced comfort for the installer or there may not be enough space.

[0005] The object of the invention is to provide a heating appliance that can be easily retrofitted so that it can be used in a hybrid heating system and associated components.

[0006] The object is solved by a flow component for a hybrid heating system, wherein the flow component comprises a housing with a recess, a first inlet portion for inletting liquid coming from a heating appliance of the hybrid heating system to the recess, a first release portion for release liquid from the recess to the heating appliance, a second inlet portion for inletting liquid coming from a further heating appliance of the hybrid heating system to the recess, a second release portion for release liquid from the recess to the further heating appliance and a separating device that is selectively arrangeable in a first position or in a second position, wherein in the first position the separating device is at least partly arranged in the recess and separates the first inlet portion from the first release portion and in the second position the separating device is arranged such that a fluid communication exists between the first inlet portion and the first release portion.

[0007] In the invention it is realized that providing the inventive flow component in a hybrid heating system or in a heating appliance that can be used in the heating system simplifies the retrofitting process. This results because, as it is explained below more in detail, the number of components that have to connected to the heating appliances and the effort of connecting the components to existing components of the heating appliance to retrofit the heating appliance so that it can be used in the hybrid heating appliance is reduced in comparison to known heating appliances.

[0008] The separating device has the advantage that the heating appliance can be operated as a standalone appliance when the heating appliance is not used in a hybrid heating system. In the operation as standalone appliance the separating device is arranged in the first position, which may be referred to as a separation portion of the recess. Additionally, the flow component enables the use of the heating appliance in a hybrid heating system, which comprises a further heating appliance. For retrofitting the heating appliance, the separating device is transferred to the second position, which is explained below more in detail. The transfer of the separating device can be easily done which simplifies the retrofit process. That means, the provision of the separating device enables the use of the heating appliance as stand-alone appliance or the use of the heating appliance in the hybrid heating system.

[0009] A heating appliance is an appliance for providing heat that can be used to heat at least one load circuit of a house, apartment and / or a building or a part thereof or a plurality thereof. The load circuit can comprise a central heating circuit and / or a domestic hot water circuit. The further heating appliance is also an appliance for providing heat that can be used to provide heat to the same or a different load circuit. The further heating appliance is of a different type than the type of the heating appliance. Specifically, the further heating appliance can be a heat pump and the heating appliance can be a boiler, in particular a gas boiler, comprising a combustion appliance.

[0010] A hybrid heating system is a system, which comprises at least two heating appliances. The term "hybrid" indicates that the two heating appliances are of at least two different types.

[0011] The term retrofitting means that the heating appliance is amended such that it can be used in a hybrid heating system. The retrofitting process can include several installation processes to enable that the heating appliance can be used in the hybrid heating system. The heating appliance can be used as a standalone appliance before a retrofit process is started. After the heating appliance is retrofitted the heating appliance can be used in the hybrid heating system.

[0012] The expression "separates the first inlet portion and the first release portion" means that the separating device is configured such that in an operation state of the heating appliance the separating device is arranged to prevent a liquid flow between the first inlet portion and the first release portion. That means, the separating device prevents that the liquid inflowing into the recess of the housing is directly released via the first release portion from the recess. As is discussed below more in detail, the liquid inflowing in the recess is released through a third release portion of the housing from the recess. In said case it is ensured that the liquid flows through the load circuit.

[0013] The first inlet portion comprises an inlet opening through which the liquid enters the recess of the housing of the flow component. The first release portion comprises a release opening through which the liquid leaves the recess of the housing of the flow component. In an operation of the heating appliance liquid heated by the heating appliance enters the flow component through the first inlet portion. The first release portion is the portion of the housing through which liquid returns to the heating appliance.

[0014] "Selectively" means that the separating device is configured such that it can be transferred between at least two positions, namely the first position and the second position or vice versa. A fluid connection exists between two components when a liquid can flow from one component to the other component.

[0015] The second position can be a position, where the separating device is arranged in a recess portion but outside a separation portion of the recess. When the separating device is arranged in the recess portion, whereby a fluid communication exists between the first inlet portion and the first release portion.

[0016] According to an embodiment the separating device can be removed from the recess when the separating device is arranged in the second position. Additionally, the separating device can be removed from the housing when the separating device is arranged in the second position. In said case the second position may be a position outside the housing. Thus, retrofitting the heating appliance to be used in the hybrid heating system can be easy implemented and does not take much time. Specifically, the separating device has to be removed from the recess. Additionally, some other components can be connected to the heating appliance, which is explained below more in detail. The separating device can be, in particular linearly, moved relative to housing. The flow component is configured such that the separating device can be removed from the recess and / or the housing without destroying the housing and / or the separating device.

[0017] The separating device can separate the second inlet portion and the second release portion when the separating device is arranged in the first position. The second inlet portion can comprise an inlet opening through which liquid heated by the further heating appliance enters the housing. The second release portion can comprise a release opening through which liquid, which transferred the heat to a medium in the load circuit and thus has lower temperature than the liquid that enters the housing through the second inlet portion, leaves the recess to the further heating appliance.

[0018] The flow component can comprise a third inlet portion for inletting liquid from the load circuit to the recess and a third release portion for releasing liquid to the load circuit. The load circuit can comprise a central heating circuit and / or a domestic water circuit. The first inlet portion and the second inlet portion can be arranged closer to the third release portion than the first release portion and the second release portion. Said arrangement of the portions ensures that liquid entering the recess through the first inlet portion and the second inlet portion leave the flow component through the third release portion. This is advantageous because liquid entering the recess by means of the first inlet portion and the second inlet portion has a high temperature so that it is ensured that liquid entering the load circuit has a high temperature.

[0019] Additionally, the distance between the first inlet portion and the first release portion along the central axis of the housing can be shorter than a distance between the second inlet portion and the second release portion. The distance can be measured along a central axis of the housing. The first inlet portion can be arranged closer to the third release portion than the second inlet portion. That means, the distance along a central axis of the housing between the second inlet portion and the third release portion is longer than a distance between the first inlet portion and the third release portion.

[0020] Such arrangement of the first and second inlet portion has the advantage to prevent that the liquid coming from the heating apparatus, in particular a boiler, leaves the flow component via the second release portion. This can be prevented by the arrangement as the liquid mass flow coming from the further heating appliance is usually higher than the liquid mass flow coming from the heating appliance.

[0021] The first and second release portions can be in the same plane. Thus, a first central axis of the first release portion and a second central axis of the second releasing portion can be arranged in the same plane. The central axis of the housing can be orthogonal to said plane. Additionally or alternatively the first and second release portions, in particular the first central axis and the second central axis, are arranged offset to each other along the central axis of the housing. The first inlet portion and the second inlet portion can be arranged offset to each other along a tangential direction of the housing.

[0022] The flow component can comprise a temperature sensor, which is arranged between the second inlet portion and the third release portion along the central axis of the housing. In other words, the temperature sensor is arranged in a region that is arranged downstream the first inlet portion and upstream the third portion. This is advantageous when the heating appliance is used in a hybrid heating system. In said case the temperature sensor measures the temperature of the mixed liquid. The mixed liquid inside the recess corresponds to the mixture of the liquid coming from the heating appliance and the liquid coming from the further heating appliance.

[0023] The measured temperature can be used for controlling the heating appliance and / or the further heating appliance. Specifically, a liquid mass flow flowing through the heating appliance can be controlled dependent on the measured temperature. Additionally a liquid mass flow flowing through the further heating appliance can be controlled dependent on the measured temperature. Further, a liquid mass flow flowing through a load circuit can be controlled dependent on the measured temperature. The control of said three mass flows is conducted when a hybrid heating appliance is provided.

[0024] The heating appliance can comprise a control unit and a pump by means of which liquid is circulated in a heating appliance circuit. When the heating appliance is used as a standalone appliance the control unit is the master control unit and controls the liquid mass flow through the heating appliance circuit and the load circuit. The pump of the heating appliance is used to control the liquid mass flows through the heating appliance and through the load circuit dependent on the measured temperature.

[0025] The further heating appliance can comprise a further control unit. In a hybrid heating system, the further control unit of the further heating appliance is the master control unit. Thus, the control unit of the heating appliance is the slave control unit in a hybrid heating system.

[0026] In the further heating appliance a further liquid pump is used to provide a liquid mass flow through the load circuit and another liquid pump is used to provide a liquid mass flow through the further heating appliance. The further control unit of the further heating appliance controls the further liquid pump dependent on the measured temperature to provide the needed liquid mass flow through the load circuit and the other liquid pump dependent on the measured temperature to provide the needed liquid mass flow through the further heating appliance,

[0027] The further control unit of the further heating appliance can communicate with another control unit of the further control appliance. In the case that the further heating appliance is a heat pump, the further control unit can communicate with the other control unit of the further heating appliance that ensures a refrigerant flow through a refrigerant circuit of the heat pump.

[0028] The control unit of the heating appliance operates in the hybrid heating system as slave control unit. Thus, the control unit of the heating appliance controls the liquid mass flow in the heating appliance circuit dependent on the measured temperature.

[0029] In a hybrid heating system, the used control units can be configured to control the liquid mass flow of the heating appliance and the liquid mass flow of the further heating appliance such that the liquid coming from the heating appliance and the liquid coming from the further heating appliance have the same temperature or have a temperature that is in a predetermined range. This can apply for all liquid mass flows of the heating appliance and / or further heating appliance. Said a control ensures that the flow component can be used as hydraulic separator. The need for a hydraulic separator results because the liquid mass flow of the heating appliance differs from the liquid mass flow of the further heating appliance.

[0030] The flow component can comprise a pressure sensor for measuring pressure inside the recess. The measured pressure can be used for safety purposes. Specifically, a responsible control unit of the heating appliance or the hybrid heating system can determine the presence of a risk state when the measured pressure is outside a predetermined pressure range, in particular is below a pressure threshold. In said case the responsible control unit can initiate measures to avoid that the heating appliance or the hybrid heating system is damaged. For example, the responsible control unit can shut down the heating appliance or the hybrid heating system.

[0031] The liquid mass flow of the heating appliance refers to the liquid that flows through the heating appliance, in particular within the heating appliance circuit, and that receives the heat from the heating appliance. The liquid mass flow of the further heating appliance refers to the liquid that flows through the further heating appliance, in particular within the further heating appliance circuit, and that receives the heat from the further heating appliance.

[0032] The separating device can be releasably, in particular directly, connected to the housing. The separating device can be, in particular directly, connected to the third release portion. The connection between the separating device and the housing, in particular the third release portion, can be a form-fit and / or force-fit connection. For example, the separating device can be screwed with the housing, in particular the third release portion. In the end, the separating device can be easily connected to and disconnected from the housing. A simple handling of the separating device can further be achieved, when the separating device is inserted into the recess through the third inlet portion or the third release portion and / or the separating device is removed from the recess via the third inlet portion or the third release portion.

[0033] The separating device can comprise a connection portion and a head portion. The connection portion can be connected with the housing when the head portion is arranged in the recess. Further, the connection portion can protrude from the third inlet portion or the third release portion. This has the advantage that the separating device can be easily removed from the housing.

[0034] The head portion can comprise a bypass valve. The bypass valve can be in an open state in which fluid communication between the first inlet portion and the first release portion is possible. Further, the bypass valve can be in a closed state in which no fluid communication is possible between the first inlet portion and the first release portion. If the heat demand of the load circuit is low or the load circuit is damaged, it is possible that the liquid mass flow through the load circuit is low. In said case the liquid mass flow that returns from the first release portion to the heating appliance, in particular to a heat exchanger of the heating appliance, is also low. The liquid mass flow might not be sufficient to receive all heat provided by the combustion appliance so that the heat exchanger might overheat.

[0035] This problem is avoided by the bypass valve. Specific the bypass valve is in the open position when the mass flow flowing through the system is too low. In other words, the provision of the bypass valve prevents that the heat exchanger is damaged as the bypass valve ensures that the liquid mass flow through the heating appliance is sufficiently high to prevent the heat exchanger to overheat.

[0036] According to an embodiment the third inlet portion and the third release portion can be arranged on opposite ends of the housing. Specifically, the third inlet portion and the third release portion can be arranged at the ends of the housing that are arranged offset to each other along the central axis of the housing. In other words, the third inlet portion is arranged at one end of the housing and the third release portion is arranged at the other end of the housing. The first inlet portion and / or the first release portion and / or the second inlet portion and / or the second release portion can be arranged between the third inlet portion and the third release portion. The handling of the flow component is simplified when the separating device is inserted into the recess and removed from the recess through the same third inlet portion or third release portion.

[0037] The housing can comprise a fourth inlet portion for inletting liquid from a further load circuit to the recess and can comprise a fourth release portion for releasing liquid from the recess to the further load circuit. Thus, it is possible that the heating appliance or the hybrid heating system is connected to two load circuits. The further load circuit can comprise a central heating circuit and / or a domestic hot water circuit. Additionally, the housing can comprise a fifth release portion for releasing liquid to an expansion vessel. The fourth inlet portion can be arranged closer to the third release portion along the central axis of the housing than the fourth release portion. The separating device can be configured such that it separates the fluid communication between the fourth inlet portion and the fourth release portion when the separating device is arranged in the recess, i.e. when the separating device is arranged in the first position.

[0038] The first inlet portion and the second inlet portion can be arranged between the third release portion and the separation portion of the recess. Additionally, the fourth release portion can be arranged between the third release portion and the separation portion of the recess. The first release portion and the second release portion can be arranged between the third inlet portion and the separation portion of the recess. Additionally, the fourth inlet portion can be arranged between the third inlet portion and the separation portion of the recess. Additionally or alternatively, the first inlet portion and the second inlet portion can be arranged opposite to the first release portion and the second release portion with respect to the separation portion of the recess. Additionally, the fourth release portion can be arranged opposite to the fourth inlet portion with respect to the separation portion of the recess.

[0039] The housing can be configured such that an inner diameter of the recess is in the range between 14mm to 25mm, in particular 18mm to 22mm. At least one of the inlet portions of the housing can have a diameter between 14mm to 25mm, in particular 18mm to 22mm. Specifically, all of the inlet portions can have the diameter between 14mm to 25mm, in particular 18mm to 22mm. Additionally, the housing can be formed as one-part. Thus, the housing does not consist of several parts which simplifies the installation. A liquid mass flow flowing through the second inlet and / or second release portion can be 1,5m 3< / h.

[0040] Of particular advantage a heating appliance comprises a combustion appliance, a heat exchanger for exchanging heat with gas combusted in the combustion appliance and an inventive flow component. The heat exchanger is fluidically connected to the first inlet portion of the flow component and to the first release portion of the flow component. In an operation of the heating appliance in which the combustion appliance heats the liquid, the heat exchanger is arranged upstream the first inlet portion and / or downstream the release portion. If the heating appliance is operated as standalone appliance and no further heating appliance is provided, the separating device is arranged in the fist position and thus at least partly in the recess.

[0041] In an embodiment in which only the heating appliance provides heat and thus is connected to the flow component, the second inlet portion and the second release portion can be closed by a closure means. Additionally, if no further load circuit is present the fourth inlet portion and the fourth release portion can also be closed by closure means. The closure means ensures that no liquid can flow out the recess an / or into the recess through the second inlet portion and / or the second release portion. The closure means can be a cap such as a screw cap.

[0042] A combustion appliance is a device designed to burn a fuel source in a controlled manner for the purpose of producing heat. This device typically comprises a combustion chamber where the combustion reaction occurs and means for conveying air and fuel gas into this chamber. The air and fuel, in particular fuel gas, can mix before the combustion chamber or inside the combustion chamber. The appliance may also include at least one heat exchanger for transferring the heat generated during combustion to a liquid or air, thereby converting the energy from the combustion process into usable heat. The combustion appliance may be designed to burn various types of fuels, including but not limited to, natural gas, propane, oil, hydrogen, biogas, or solid fuels such as wood or pellets. A heating appliance can be a boiler, space heater, oven, or a gas water heater.

[0043] The heating appliance can comprise a casing wherein the flow component, the heat exchanger and the flow component are arranged inside an inner space of the casing. The casing delimits the inner space. The heating appliance can be a floor standing boiler and / or comprise a water tank. In said case the casing can be arranged on water tank casing. The water tank is arranged in a space of the water tank casing.

[0044] Of particular advantage is a hybrid heating system comprising an inventive heating appliance and a further heating appliance. The further heating appliance is of another type than the heating appliance. The further heating appliance is fluidically connected to the second inlet portion and the second release portion and the separating device is arranged in the second position. In other words, the separating device is removed from the recess of the housing and the separating device. The heating appliance can comprise a combustion appliance and the further heating appliance can be a heat pump. In an operation of the hybrid heating system, liquid from the heating appliance and from the further heating appliance is inserted through the inlet portions of the flow component to the recess of the housing of the flow component. Said liquid is mixed in the recess of the flow component and leaves the flow component through the third release portion. If a further load circuit is provided, a part of the mixed liquid leaves the recess through the fourth release portion to the further load circuit.

[0045] For retrofitting the heating appliance to be used in the hybrid heating system the separating device can be removed from the housing when the further heating appliance is connected to the flow component. By removing the separating device from the housing, the flow component becomes a hydraulic separator. The hydraulic separator allows the higher liquid mass flow of the further heating appliance to be decoupled from the smaller liquid mass flow of the heating appliance.

[0046] Additionally, the retrofitting process comprises the steps of fluidically connecting the second inlet portion and the second release portion to respective pipes of the further heating appliance. Further, a liquid pump can be connected downstream the third release portion and upstream the load circuit for pumping liquid to the load circuit. Additionally, a further control unit for controlling a further heating appliance is electronically connected to the temperature and / or pressure sensor and / or to the control unit of the heating appliance. In the end, the retrofitting process is simple by removing the separating device from flow component and by connecting some components of the further heating appliance to the flow component and the heating appliance.

[0047] The further heating appliance can be at least partly arranged outside of the casing of the heating appliance. Thus, an installation is simplified as the majority of parts of the further heating appliance can be arranged outside the heating appliance.

[0048] According to the invention an inventive flow component can be used to retrofit a heating appliance comprising a combustion appliance to a hybrid heating system comprising the heating appliance and a further heating appliance, in particular a heat pump, or vice versa. Additionally, the flow component can be used in a heating appliance comprising a combustion appliance or in a hybrid heating system comprising a heating appliance, which has a combustion appliance, and a heat pump. If the flow component is used in heating appliance the separating appliance is arranged in first position. If the flow component is used in hybrid heating appliance, the separating device is arranged in the second position.

[0049] In the figures, the subject-matter of the invention is schematically shown, wherein identical or similarly acting elements are usually provided with the same reference signs. Figure 1a perspective view of the flow component according to the invention. Figure 2a cross-section view of the flow component shown in figure 1. Figure 3a perspective view of a separating device. Figure 4an enlarged part of the cross section shown in fig. 2. Figure 5aa plurality of components of a heating appliance from a first perspective. Figure 5ba plurality of components of the heating appliance from a second perspective. Figure 6a heating appliance without several casing walls. Figure 7a plurality of the components of a heating appliance and a further heating appliance. Figure 8a schematic overview of a hybrid heating system. Figure 9a heating appliance that is connected with two load circuits. Figure 10a hybrid heating system that is connected with two load circuits.

[0050] A flow component 1 as shown in fig. 1 comprises a housing 3 with a recess 4 shown in fig. 2. Additionally, the flow component 1 comprises a first inlet portion 5 for inletting liquid coming from a heating appliance 6 of a hybrid heating system 2 both shown in fig. 10 to the recess 4 and a first release portion 7 for releasing liquid from the recess 4 to the heating appliance 6. Further, the flow component 1 comprises a second inlet portion 8 for inletting liquid coming from a further heating appliance 9 shown fig. 10 of the hybrid heating system 2 to the recess 4 and a second release portion 10 for releasing liquid from the recess 4 to the further heating appliance 9.

[0051] The flow component 1 comprises also a third release portion 13 and a third inlet portion 11. A load circuit 12 shown in fig. 10 is fluidically connected to the third release portion 13 and the third inlet portion 11. The third release portion 13 is arranged at one end of the housing 3 and the third inlet portion 11 is arranged at the opposite end of the housing 3. The end and the other end refer to a central axis L of the housing 3.

[0052] In addition, the flow component 1 comprises a fourth inlet portion 20 and a fourth release portion 22, which are connected to a further load circuit. 21 shown in fig. 9. Thus, the flow component 1 can be fluidically connected to two load circuits as it is described in detail in figures 9 and 10. The flow component 1 also comprises a fifth release portion 23, which is connected with an expansion vessel 24 that is shown in fig. 5.

[0053] Figure 2 shows cross-section of the flow component 1 shown in figure 1. The flow component 1 comprises a separating device 14, which is not shown in fig. 1. The separating device 14 is selectively arrangeable in a first position or in a second position. In the first position the separating device 14 is at least partly arranged in the recess 4 and fluidically separates the first inlet portion 5 and the first release portion 7 from each other. Thus, the separating device 14 prevents a liquid flow between the first inlet portion 5 and the first release portion when it is arranged in the first position. Fig. 2 shows the separating device 14 that is arranged in the first position.

[0054] In the second position the separating device 14 is arranged such that a fluid communication exists between the first inlet portion 5 and the first release portion 7. Thereto, the separating device 14 is removed from the housing 3. Fig. 1 shows the flow component without the separating device 14, which means that the separating device 14 is not arranged in the recess 4 and thus is arranged in the second position.

[0055] The first inlet portion 5 and the second inlet portion 8 are arranged offset to each other along the central axis L of the housing 3. The first inlet portion 5 is arranged closer to the third release portion 13 than the second inlet portion 8 with respect to the central axis L. In this example, the first inlet portion 5 and the second inlet portion 8 are arranged offset to each other along a tangential direction of the housing 3.

[0056] The first release portion 7 and the second release portion 10 are not arranged offset to each other along the central axis L of the housing 3. Thus, a plane E exists which is orthogonal to the central axis L of the housing 3 and in which a central axis of the first release portion 7 and a central axis of the second release portion 10 are arranged. In this example, the first release portion 7 and the second release portion 10 are arranged offset to each other along a tangential direction of the housing 3.

[0057] In this example, the fourth inlet portion 20 and the fifth release portion 23 are not arranged offset to each other along the central axis L of the housing 3. Additionally, the fourth inlet portion 20 and the fifth release portion 23 are not arranged offset to the first release portion 7 and the second release portion 10. Thus, a central axis of the fourth inlet portion 20 and a central axis of the fifth release portion 23 are arranged in the plane E.

[0058] The fourth release portion 22 is arranged offset to the second inlet portion 8 along the central axis L of the housing 3. Additionally, the fourth release portion 22 is arranged closer to the third release portion 13 than the second inlet portion 8.

[0059] The flow component 1 comprises a temperature sensor 15 and a pressure sensor 16. The temperature sensor 15 measures the temperature of the liquid in the recess 4 and the pressure sensor 16 measures the pressure of the liquid. Both sensors are connected to a non-shown control unit of the heating appliance 6. The temperature sensor 15 measures a liquid temperature in a recess portion that is arranged between the third release portion 13 and the first inlet portion 5 with respect the central axis L of the housing 3.

[0060] Fig 2. shows a state in which the separating device 14 is arranged in the first position and fig. 3 shows a perspective view of the separating device 14. The separating device 14 comprises a connection portion 17 and a head portion 18 that is arranged at one end of the separating device 14. The connection portion 17 is connected to the head portion 18 and protrudes from the third release portion 13 when the separating device 14 is arranged within the recess 4 of the housing 3. Specifically, the head portion 18 and a part of the connection portion 17 are arranged in the recess 4 in the first position.

[0061] The connection portion 17 comprises a connection part 30 that is used to connect the separating device with the third release portion 13. The connection part 30 can be configured such that, after it is connected with the third release portion 13, the separating device 14 cannot be moved relative to the housing 3. The connection part 30 can comprise an external thread that engages with an internal thread of the recess 4 to connect the separating device 14 with the housing.

[0062] The head portion 18 seals the recess 4 when the separating device 14 is in the first position as shown in fig. 2. Thus, the head portion 18 is configured such that it prevents a liquid flow between the first inlet portion 5 and the first release portion 7. Thereto, the head portion 18 is arranged in a separation portion of the recess 4 that is arranged between the first inlet portion 5 and the first release portion 7 along the central axis L of the housing 3.

[0063] In the example shown, the head portion 18 comprises a bypass valve 19 at one end and a hole 31 through which liquid being in the recess 4 and outside the head portion 18 can enter an inner space of the head portion 18. An enlarged part of the head section 18 is shown in fig. 4 wherein the enlarged part is indicated with the letter "C" in fig. 2.

[0064] The bypass valve 19 comprises a valve element 33 that is arranged in an inner space delimited by a wall 32 of the bypass valve 19. The valve element 33 can be moved from a closed position in which no liquid flows through the bypass valve 19 to an open position in which a bypass liquid flow through the bypass valve 19 is possible. The valve element 33 is moved to the open position when a pressure that is applied by the liquid that entered the bypass valve 19 through the hole 31 is greater than a threshold. In said case a bypass liquid can flow through the bypass valve and thus through the separating device 14, whereas the bypass valve otherwise prevents liquid flow through the separation device 14.

[0065] Figure 5a shows a plurality of components of a heating appliance 6 from a first perspective and fig. 5b shows a plurality of components of the heating appliance 6 from a second perspective. The heat exchanger 27 of the heating appliance 6 is fluidically connected to the flow component 1 and comprises an expansion vessel 24, which is fluidically connected to the fifth release portion 23 of the flow component 1. Both figures show the heating appliance 6 that works as a standalone appliance. That means, the heating appliance 6 is the only appliance that provides heat in this embodiment.

[0066] The heating appliance 6 comprises a heat exchanger 27 and a combustion appliance 26 shown in fig 6 that transfers heat to the heat exchanger 27. Said heat exchanger 27 is connected by means of a first inlet pipe 34 with the first inlet portion 5 of the flow component 1. Additionally, the heat exchanger 27 is connected by means of pipes 35, 35a with the first release portion 7. There might be further pipes that are needed to connect the heat exchanger 27 with the first inlet portion 5 or with the first release portion 7. Said further pipes are indicated with the dotted line in fig. 5. All said components are part of a heating appliance circuit.

[0067] The heating appliance 6 also comprises a three-way valve 36. The three-way valve 36 is connected by means of a third return pipe 37 to the third release portion 13. In this embodiment the load circuit 12 has two non-shown heating circuits, namely a central heating circuit and a domestic hot water circuit.

[0068] The three-way valve 33 is connected by means of a third return sub pipe 38 with the central heating circuit and by means of a further third return sub pipe 39 with the domestic hot water circuit. The liquid that passes through the load circuit 12, namely the central heating circuit, returns to the flow component 1, in particular to the third inlet portion 11, by means of a third inlet pipe 40.

[0069] Liquid coming from the domestic hot water circuit flows through a further first inlet pipe 49 and is mixed with the liquid that is coming from the heat exchanger 27 and that flows through an outlet pipe from the heat exchanger 35a. The heating appliance 6 comprises a connection element 50 that is fluidically connected to the outlet pipe from the heat exchanger 35a and the further first inlet pipe 49. An outlet of the connection element 50 is fluidically connected with an end of the first return pipe 35. Another end of the first return pipe 35 is fluidically connected to the first release portion 7 of the flow component 1.

[0070] The other inlet or release portions of the housing 3 are closed by a cap 41 so that no liquid flows through said portions.

[0071] Further, the heating appliance 6 comprises a liquid pump 42 for circulating the liquid through the load circuit, in particular the central heating circuit and / or the domestic hot water circuit. Additionally, the liquid pump 42 ensures that the liquid is circulated through the heating appliance circuit. The liquid pump 42 is controlled by the non-shown control unit that operates as master control unit in the heating appliance. The control of the liquid pump 42 depends on the measured temperature. The heating appliance 6 further comprises a gas pipe 43 by means of which gas can flow to the non-shown combustion appliance 26 of the heating appliance 6.

[0072] In this embodiment the separating device 14 is arranged in the first position. Thus, the separating device 14 fluidically separates the first inlet portion 5 and the first release portion 7 from each other and ensures that the liquid that enters the recess 4 flows through the load circuit 12.

[0073] Figure 6 shows the heating appliance 6 with a combustion appliance 26 and a casing 28. The heating appliance 6 comprises the components discussed above in fig. 5. The casing 28 delimits an inner space in which the components discussed above with respect to fig. 5 are arranged. In figure 6 two casing walls are removed so that it is possible to see the insight of the heating appliance 6. In an operation mode of the heating appliance 6 the casing walls are in place.

[0074] Figure 7 shows a plurality of the components of a heating appliance 6 and a further heating appliance 9 that form the hybrid heating system 2. The heating appliance 6 can be retrofitted to be used in the hybrid heating system 2 by arranging the separating device 14 in the second position. Thereto, the separating device 14 is removed from the housing 3. Thus, the flow component 1 can work as a hydraulic separator for the liquid mass flows of the further heating appliance and the liquid mass flows of the heating appliance. The removed separating device 14 is not shown in fig. 7.

[0075] Additionally, a second inlet pipe 44 is directly connected to the second inlet portion 8 at one end of the second inlet pipe 44 and a second return pipe 45 is directly connected to the second release portion 10 at one end of the second return pipe 45. The second inlet pipe 44 and the second return pipe 45 are arranged in the inner space delimited by the casing of the heating appliance 6 shown in fig. 6. The second inlet pipe 44 is connected to a first circuit pipe 46 of the further heating appliance 9 at another end of the second inlet pipe 44 and the second return pipe 45 is connected to a second circuit pipe 47 of the further heating appliance at another end of the second return pipe 45. The first circuit pipe 46 and the second circuit pipe 47 are arranged outside the casing shown in fig. 6.

[0076] To retrofit the heating appliance to be used in the hybrid heating system 2 the following steps have to be done in addition to removing the separating device 14 from the housing and to connecting the pipes 44-47 with the flow component 1. A further liquid pump 51 is placed downstream of the third release portion 13 and upstream the three-way valve 36. A further control unit 25 of the further heating appliance 9 is also arranged inside the casing 28 shown in fig. 6 and electrically connected with the temperature and pressure sensor.

[0077] In a hybrid heating system comprising the retrofitted heating appliance 6 and the further heating appliance 9, the further control unit 25 of the further heating appliance 9 operates as master control unit. The non-shown control unit of the heating appliance 6 operates as slave control unit and controls the liquid pump 42. The further control unit 25 of the further heating appliance 9 controls the further liquid pump 51 and thus the liquid mass flow through the load circuit 12. Additionally, the further control unit 25 of the further heating appliance controls a non-shown liquid pump of the further heating appliance 9 and thus controls the liquid mass flow through the further heating appliance circuit.

[0078] Figure 8 shows a schematic overview of a hybrid heating system 2. The hybrid heating system 2 comprises the heating appliance 6 and the further heating appliance 9. The heating appliance 6 can be a combustion appliance, in particular a boiler, in particular a gas boiler, and the further heating appliance 9 can be a heat pump. The heating appliance 6 can in addition to the components discussed in the figures 3 to 7 comprise a non-shown water tank. In said case the components shown in figure 6 are arranged above the water tank.

[0079] The further heating appliance 9 comprises a heating unit 48. Said heating unit 48 is arranged outside the casing 28 of the heating appliance 6. The heating unit 48 can comprise the refrigerant circuit of a heat pump. In said case the further control unit 25 of the further heating appliance directly or indirectly controls the refrigerant flow within a refrigerant circuit of the heat pump. Additionally, the further heating apparatus 9 comprises a retrofit kit 52 having the second inlet and return pipe 44, 45, the circuit pipes 46, 47, the further control unit 25 and the further liquid pump 51 which have to be connected with heating appliance 6 to retrofit the heating appliance 6 so that it can be used in the hybrid heating system 2.

[0080] Figure 9 shows a heating appliance 6 that is connected with two load circuits 12 and 21. The fluid connections between the flow component 1, the heating circuit 6 and the load circuits 12, 21 are indicated with dotted lines. The separating device 14 is arranged inside the recess 4 and thus in the first position.

[0081] Liquid heated in the heat exchanger 26 of the heating appliance 6 enters the recess 4 via the first inlet portion 5. The heated liquid flows through the third release portion 13 to the load circuit 12 in which heat is transferred to another medium. The cooled liquid enters the flow component 1 through the third inlet portion 11.

[0082] Additionally, the heated liquid flows through the fourth release portion 22 to the further load circuit 21. After the heat is transferred to a medium in the further load circuit 21, the cooled liquid enters the flow component 1 through the fourth inlet portion 20. The fourth inlet portion 20 is arranged in front of the cross-section plane that is shown in fig. 9. Thus, fig. 9 does not show the fourth inlet portion 20. However, the arrow indicating the liquid flow from the further load circuit 21 ends at a position in the flow component, where the fourth inlet portion is located. The liquid that has entered the recess 4 through the third inlet portion 11 and the fourth inlet portion 20 flows through the first release portion 7 back to the heat exchanger 26 and is heated again in the heat exchanger 27 of the heating appliance 6.

[0083] The second release portion 10 is arranged behind the cross section plane that is shown in fig. 9. As the heating appliance 6 is in Fig. 9 in stand-alone operation, it is closed with a non-shown cap.

[0084] Figure 10 shows a hybrid heating system 2 comprises the heating appliance 6 and the further heating appliance 9. The hybrid heating system 2 is connected with two load circuits 12, 21. As the further heating appliance 9 is connected to the flow component 1, the separating device 14 is removed from the housing 3. In fig. 10 the separating device 14 that is arranged outside the housing in the second position is shown.

[0085] The hybrid heating system 2 can be operated in different modes. In a first mode only the heating appliance 6 is operated and the further heating appliance 9 is not operated. In a second mode only the further heating appliance 9 is operated and the heating appliance 6 is not operated. In a third mode the heating appliance 6 and the further heating appliance 9 are operated. The hybrid heating system 2 can be selectively operated in one of said three modes. Further, a non-shown pump or valve can selectively enable or disable liquid flow to at least one of the load circuits 12, 21.

[0086] In the following, the operation of the hybrid heating system 2 is explained in which the heating appliance 6 and the further heating appliance 9 are operated. The liquid flow from the heating appliance 6 to the flow component 1 and to the load circuits 12, 21 of is basically the same as discussed above in figure 9 so that in the following the differences are discussed.

[0087] A difference is that the liquid coming from the heating appliance 6 mixes with the liquid coming from further heating appliance 9 and entering the recess 4 through the second inlet portion 8 before it leaves the flow component 1 to the load circuits 12, 21.

[0088] A further difference is that a part of the liquid being in the recess 4 and coming from the load circuits 12, 21 leaves the flow component 1 to the heating appliance 6 and another part leaves the flow component 1 to the further heating appliance 9 through the first release portion 7 or the second release portion 10. Herein, the flow component 1 acts as a hydraulic separator. The hydraulic separator allows the higher liquid mass flow of the further heating appliance to be decoupled from the smaller liquid mass flow of the heating appliance.

[0089] Likewise, to fig. 9 the cross-section plane through the flow component 1 is such arranged that the fourth inlet portion 20 is not shown in fig. 10. However, the fourth inlet portion 20 is located at the location of the flow component at which the second release portion 10 is arranged along the central axis L of the housing.Reference Signs

[0090] 1Flow component 2Hybrid heating system 3Housing 4Recess 5First inlet portion 6Heating appliance 7First release portion 8Second inlet portion 9Further heating appliance 10Second release portion 11Third inlet portion 12Load circuit 13Third release portion 14Separating device 15Temperature sensor 16Pressure sensor 17Connection portion 18Head portion 19Bypass valve 20Fourth inlet portion 21Further load circuit 22Fourth release portion 23Fifth release portion 24Expansion vessel 25Further control unit for further heating appliance 26Combustion appliance 27Heat exchanger 28Casing 30Connection part 31Hole 32Wall 33Valve element 34First inlet pipe 35First return pipe 35aOutlet pipe 36Three way valve 37Third return pipe 38Third return sub-pipe 39Further third return sub-pipe 40Third inlet pipe 41Cap 42Liquid pump 43Gas pipe 44Second inlet pipe 45Second return pipe 46First circuit pipe of the further heating appliance 47Second circuit pipe of the further heating appliance 48Heating unit 49Further first inlet pipe 50Connection element 51Further liquid pump 52Retrofit kit LCentral axis of the housing EPlane

Claims

1. Flow component (1) for a hybrid heating system (2), wherein the flow component (1) comprises a housing (3) with a recess (4), a first inlet portion (5) for inletting liquid coming from a heating appliance (6) of the hybrid heating system (2) to the recess (4), a first release portion (7) for releasing liquid from the recess (4) to the heating appliance (6), a second inlet portion (8) for inletting liquid coming from a further heating appliance (9) of the hybrid heating system (2) to the recess (4), a second release portion (10) for releasing liquid from the recess (4) to the further heating appliance (9) and a separating device (14) that is selectively arrangeable in a first position or in a second position, wherein in the first position the separating device (14) is at least partly arranged in the recess (4) and separates the first inlet portion (5) from the first release portion (7) and in the second position the separating device (14) is arranged such that a fluid communication exists between the first inlet portion (5) and the first release portion (7).

2. Flow component (1) according to claim 1, characterized in that a. the separating device (14) is removed from the recess (4) or the housing (3) when the separating device (14) is arranged in the second position and / or b. the separating device (14) separates the second inlet portion (8) and the second release portion (10) when the separating device (14) is arranged in the first position.

3. Flow component (1) according to claim 1 or 2, characterized in that the flow component (1) comprises a third inlet portion (11) for inletting liquid from a load circuit (12) to the recess (4) and a third release portion (13) for releasing liquid to the load circuit (12).

4. Flow component (1) according to claim 3, characterized in that the first inlet portion (5) is arranged closer to the third release portion (13) than the second inlet portion (8).

5. Flow component (1) according to any one of the claims 1 to 4, characterized in that a. the flow component (1) comprises a temperature sensor (15) which is arranged between the second inlet portion (8) and the third release portion (13) and / or in that b. the flow component (1) comprises a pressure sensor (16) for measuring pressure inside the recess (4).

6. Flow component (1) according to any one of the claims 1 to 5, characterized in that a. the separating device (14) is releasably connected to the housing (3) and / or in that b. the separating device (14) is insertable into the recess (4) through the third inlet portion (11) or the third release portion (13) and / or the separating device (14) is removable from the recess (4) through the third inlet portion (11) or the third release portion (13).

7. Flow component (1) according to any one of the claims 1 to 6, characterized in that the separating device (14) comprises a connection portion (17) and a head portion (18) wherein the connection portion (17) is connected with the housing (3) when the head portion (18) is arranged in the recess (4) and / or the head portion (18) comprises a bypass valve (19).

8. Flow component (1) according to any one of the claims 1 to 7, characterized in that the third inlet portion (11) and the third release portion (13) are arranged on opposite ends of the housing (3).

9. Flow component (1) according to any one of the claims 1 to 8, characterized in that a. the housing (3) comprises a fourth inlet portion (20) for inletting liquid from a further load circuit (21) to the recess (4) and comprises a fourth release portion (22) for releasing liquid from the recess (4) to the further load circuit (21) and / or b. the housing (3) comprises a fifth release portion (23) for releasing liquid to an expansion vessel (24).

10. Flow component (1) according to any one of claims 1 to 9, characterized in that a. an inner diameter of the recess (4) is in the range between 14mm to 25mm, in particular 18mm to 22mm, and / or in that b. the housing (3) is formed as one part.

11. Heating appliance (6) comprising a combustion appliance (26), a heat exchanger (27) for exchanging heat with gas combusted in the combustion appliance (26) and a flow component (1) according to any one of the claims 1 to 10, wherein the heat exchanger (27) is fluidically connected to the first inlet portion (5) and to the first release portion (7) of the flow component (1).

12. Heating appliance (6) according to claim 11, characterized in that a. the heating appliance (6) comprises a casing (28) wherein the flow component (1), the heat exchanger (27) and the flow component (1) are arranged inside an inner space of the casing (28) and / or b. the separating device (14) is arranged in the first position.

13. Hybrid heating system (2) comprising a heating appliance (6) according to claim 11 or 12 and a further heating appliance (9) wherein the further heating appliance (9) is fluidically connected to the second inlet portion (8) and the second release portion (10) and the separating device (14) is arranged in the second position.

14. Hybrid heating system (2) according to claim 13, characterized in that the further heating appliance (9) is at least partly arranged outside of the casing (28).

15. Use of the flow component (1) according to any one of the claims 1 to 10 to retrofit a heating appliance (6) comprising a combustion appliance (26) to a hybrid heating system (2) comprising the heating appliance (11) and a further heating appliance, in particular a heat pump, or vice versa.

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