Automatic air vent for use in a gas separator of a heat pump system

Abstract

Automatic air vent (100, 400, 500, 600) for use in a gas separator of a heat pump system, wherein the automatic vent (100, 400, 500, 600) has at least two vent valves (110, 200, 410, 510, 610) and a float (120, 420, 520, 620), wherein each vent valve (110, 200, 410, 510, 610) has a lever arm (111, 411, 511) with a contact medium, wherein the float (120, 420, 520, 620) has a respective contact area (121, 321, 421, 521, 621) which is designed to contact the contact medium of each vent valve (110, 200, 410, 510, 610), wherein the float (120, 420, 520, 620) contacts each vent valve (110, 200, 410, 510, 610) in such a way that, when it rests on a liquid, it opens a vent valve (110, 200, 410, 510, 610) depending on the liquid level, and wherein the automatic vent (100, 400, 500, 600) is designed to open at least two vent valves (110, 200, 410, 510, 610) at different fill levels.

Description

[0001] The invention relates to an automatic air vent for use with a gas separator of a heat pump system, in particular in, on or at a gas separator of a heat pump system.

[0002] Such heat pump systems have a primary circuit for conveying a refrigerant and a secondary circuit for conveying water, whereby heat can be transferred between the refrigerant and the water by means of a heat exchanger.

[0003] When using R290, i.e., propane, as a refrigerant, a problem has been identified: a defect, such as a general malfunction or damage caused by freezing water, in the heat exchanger (which may be a plate heat exchanger, for example) can allow refrigerant to enter the secondary circuit, particularly the heating section of the secondary circuit. This refrigerant can then be distributed via the secondary circuit's distribution system into a house that is to be heated by that section. If propane, a flammable refrigerant, enters the system, a combustible gas can be produced, posing a danger to the house and its occupants.

[0004] DD 10 037 A1 describes a self-acting venting device for wastewater pressure lines, the mechanism of which is actuated by a float.

[0005] From FR 2 232 723 A1 a venting and aeration valve for hydraulic lines is known, consisting of a hollow body which is provided with a vent opening at its upper part and a float which can move vertically in the body to close an opening when the fluid in the valve rises.

[0006] In JP H07- 19 360 A a pump for circulation is described which is equipped with a vent valve, wherein the vent valve serves to detect the operating state of the sensor and is equipped with a vent valve device.

[0007] It is known from the prior art to provide an automatic air vent in the secondary circuit of heat pumps, which has a blow-off capacity of between 0.2 and 2.5 NL / s. However, automatic air vents with higher blow-off capacities have significantly larger dimensions (by a factor of 10 to 100).

[0008] A disadvantage of the current technology is that the automatic air vents used in heating systems are not large enough to remove refrigerant entering the secondary circuit on their own. Automatic air vents with a higher discharge capacity are significantly larger and therefore more expensive, making them unsuitable for high-volume series production.

[0009] Up to now, state-of-the-art automatic air vents have relied on large volumes (10 to 100 times larger than those used in heating systems), large floats, and lever-operated valves. Furthermore, these larger automatic air vents are typically made of brass or stainless steel, resulting in high costs.

[0010] The object of the present invention is therefore to provide an automatic air vent for a gas separator (for example, a cyclone separator) in order to remove large quantities of refrigerant gas from the gas separator, and thus from the heating system, so that the refrigerant does not enter living areas via the water circuit and without causing a significant pressure increase in the system.

[0011] According to a first aspect of the invention, an automatic air vent for use in a gas separator of a heat pump system is proposed, wherein the automatic air vent comprises at least two air vents and a float, wherein each air vent has a lever arm with a contact means, wherein the float has a respective contact area configured to contact the contact means of each air vent, wherein the float contacts each air vent such that, when in contact with a liquid, it opens an air vent depending on the liquid level, and wherein the automatic air vent is configured to open the at least two air vents at different liquid levels. For example, the contact can be provided by a mechanical connection, i.e., that the contact means of the air vent is mechanically connected to the contact area of ​​the float.Alternatively, a detachable connection is conceivable in which a force is transferred from the contact area of ​​the float to the contact medium of the vent valve when the float sinks, but then the contact between the contact area and the contact medium is lost and no force is transferred when the float rises.

[0012] By using such an automatic air vent, which is designed to open at least two vent valves at different fill levels, the actuating force of the valves (by opening the valves at different fill levels) can be reduced, thus achieving a high blow-off capacity in a small installation space.

[0013] The vent according to the invention is an automatic vent and is designed to open automatically by means of the float depending on a water level in the gas separator.

[0014] The automatic air vent according to the invention is preferably intended for a gas separator of a heat pump system, but the invention is not limited to a heat pump system. Alternatively, the automatic air vent according to the invention can also be provided in another system with high venting capacity.

[0015] The vent valve is designed to release gas that is located within the system, for example the heat pump system, in particular the gas separator of the heat pump system, in a controlled manner.

[0016] In an advantageous embodiment, the at least two vent valves are actuated sequentially, particularly sequentially when the fill level falls. Preferably, a force acts first on at least one lever arm of the at least two vent valves, and then a further force acts on at least one further lever arm of the at least two vent valves. This allows at least one vent valve to open first when the fill level drops, and at least a second vent valve to open when the fill level drops further. Preferably, three or four vent valves are used in the automatic vent according to the invention.

[0017] Preferably, the at least two vent valves are arranged at different heights relative to the height of the float or the automatic air vent. The arrangement of the at least two vent valves also allows them to open at different fill levels.

[0018] The float can comprise one or two floats. Particularly preferably, the float comprises at least two floats, each of which is connected to at least one vent valve. This ensures that even if one float jams, 50% of the blow-off capacity is still maintained. Furthermore, a float with at least two floats, preferably exactly two, improves the ratio of lever length to float width, thus enabling high leverage relative to the dimensions of the automatic vent. Particularly preferably, the automatic vent has at least four vent valves, each of which is connected to at least two floats.

[0019] In a further advantageous embodiment, the respective contact area of ​​the float is designed to open at least two vent valves at different fill levels. For example, the contact area can be designed as one or more plates with at least one eyelet projecting from the float, particularly upwards. "Upwards" here means that the plate projects from an upper side of the float opposite the side that rests on the water, which can also be understood as the lower side of the float. In particular, the orientation of the float on the water, i.e., within the automatic vent, defines a direction corresponding to an up-down direction, in which the height of the float, the plate, etc., extends.

[0020] The contact element of each vent valve is designed to contact the contact area of ​​the float. For example, the contact element can be a rod that engages in one of the eyelets. The plate(s) can have eyelets arranged at different heights on the plate(s), or the eyelets can be arranged at different heights relative to the height of the float, so that a force acts on the contact element of the vent valve, and thus on the vent valve, depending on the water level. In particular, a force first acts on at least one lever arm of the at least two vent valves, and then a further force acts on at least one other lever arm of the at least two vent valves.

[0021] In a preferred embodiment, the respective contact area is arranged closer to the center of gravity of the float than to an outer edge of the float. This effectively prevents the float from jamming.

[0022] In a preferred embodiment, the automatic air vent according to the invention is attached to the gas separator by means of a push-fit connector. This allows for easy replacement of the automatic air vent. Furthermore, the push-fit connector can include a spring-loaded valve, i.e., a shut-off valve. This allows the automatic air vent to be replaced without draining the water from the water circuit.

[0023] In a particularly preferred embodiment, the automatic air vent comprises three or four vent valves. If three vent valves are provided, the automatic air vent is preferably configured such that all three vent valves are opened sequentially depending on the water level. If four vent valves are provided, the automatic air vent can be configured such that two vent valves are opened at a first water level, and two vent valves are opened at a second water level that differs from the first, or that all four vent valves are opened sequentially depending on the water level. In a case where the float comprises a float and four vent valves, it is preferred that the four vent valves are opened sequentially depending on the water level.

[0024] Additionally or alternatively, a float can be provided with two, preferably two identical, floats, wherein preferably the at least two vent valves each contact a float, and further preferably two vent valves each contact a float. It is further preferred that two vent valves are opened at different water levels, and further preferred that two vent valves are opened at the same water level. In the case where two floats and four vent valves are provided, it is particularly preferred that two vent valves contacting a float are opened at different water levels.

[0025] In particular, each vent valve can include a fixed part, a sealing ring, a spring, and a moving part.

[0026] Preferably, the float includes at least one hollow body.

[0027] In another aspect of the invention, a gas separator for a secondary circuit of a heat pump system is proposed, which has an automatic air vent according to one of the embodiments described above.

[0028] It is preferred that the gas separator includes a shut-off valve arranged within the gas separator such that, when the shut-off valve is closed, a volume of the gas separator containing the automatic air vent is separated from a volume of the gas separator containing a liquid. Particularly preferably, the volume of the gas separator containing the liquid comprises the majority of the liquid in the gas separator. This allows for easy replacement of the automatic air vent, even if water is present in the gas separator.

[0029] According to a further aspect of the invention, a heat pump system is proposed comprising a primary circuit for conveying a refrigerant, a secondary circuit for conveying water and a heat exchanger for transferring heat between the refrigerant and the water, wherein the secondary circuit comprises a gas separator according to one of the present embodiments.

[0030] Features of advantageous embodiments of the invention are defined in particular in the dependent claims, with further advantageous features, embodiments and configurations also being apparent to the person skilled in the art from the above explanations and the following discussion.

[0031] The present invention will now be further illustrated and explained with reference to exemplary embodiments shown in the figures. These show: Fig. 1a a schematic representation to illustrate a first embodiment of the automatic vent according to the invention from above, Fig. 1b a schematic representation to illustrate the first embodiment of the automatic air vent from the side, Fig. 2 a schematic representation to illustrate a first embodiment of the vent valve, Fig. 3 A schematic representation illustrating an exemplary embodiment of a floating body from three different perspectives, Fig. 4 a schematic representation to illustrate a second embodiment of the automatic air vent according to the invention, Fig. 5 a schematic representation to illustrate a third embodiment of the automatic air vent according to the invention, Fig. 6a a schematic representation to illustrate a fourth embodiment of the automatic vent according to the invention from the side, and Fig. 6b a schematic representation to illustrate the fourth embodiment of the automatic air vent from above.

[0032] In the accompanying drawings and the explanations relating to these drawings, corresponding or related elements are marked with corresponding or similar reference symbols, where appropriate, even if they are found in different embodiments.

[0033] Fig. Figure 1 shows a schematic representation to illustrate a first embodiment of the automatic air vent according to the invention from above.

[0034] The automatic air vent 100 comprises four air vents 110 and a float 120 with two floats 122, 123. Each air vent 110 has a lever arm 111 with a contact means, wherein in the present embodiment the contact means is designed as a rod-shaped end of the lever arm 111.

[0035] The float 120 comprises two uniform float bodies 122, 123, each having the shape of a longitudinally sectioned half of a vertical cylinder with a semicircular base. Alternatively, it is also conceivable that the float 120 comprises, for example, a float body in the shape of a vertical cylinder with a circular base.

[0036] Each float 122, 123 comprises a contact area 121, wherein, in the illustrated embodiment, each float 122, 123 comprises a contact area 121 that has two plates, each with an eyelet. Each plate contacts a vent valve 110, and thus each float 122, 123 contacts two vent valves 110, in particular two lever arms 111 of two vent valves 110, via the contact area 121. The contact area 121 is configured to contact two contact means of each of the two vent valves 110, wherein the respective two vent valves 110 that contact a float 122, 123 are parallel to each other. Each of the floats 122, 123 contacts two vent valves 110 in such a way that each float 122, 123, when resting on a liquid, opens only one vent valve 110 depending on the liquid level, whereby the float 120 / the floats 122, 123 respectivelyThe automatic air vent 100 in the illustrated embodiment is configured to open two of the four air vents 110, each of which contacts one of the two floats 122, 123, at the same fill level. Alternatively, the float 120 / the floats 122, 123 can also be configured such that all four air vents 110 are opened at different fill levels, i.e., that as the fill level falls, one air vent after the other is actuated. For example, the design of the floats 122, 123 can then also differ from one another.

[0037] The further design of the automatic air vent 100, in order to open the at least two vent valves 110 at different fill levels, is in particular Fig. See 1b.

[0038] Fig. Figure 1b shows a schematic representation illustrating the first embodiment of the automatic air vent from the side. From the side, only two of the four air vent valves 110 are visible, with each of the floats 122, 123 shown from the side with a height h. The floats 122, 123 each comprise a contact area 121 that projects upwards from the side of the float 120.

[0039] Particularly in the illustration of the left float body 122, it can be seen that the contact area 121 has two plates of different heights, each plate having an eyelet. Thus, the float 120, or rather the automatic vent 100, is designed to open the two vent valves 110, which contact the contact area 121 via the contact medium 111, at different water levels. This causes the two vent valves 110, which contact the left float 120, to be actuated sequentially.

[0040] The right float 123 also includes a contact area 121 with two plates of different heights, which protrude upwards from the float 123 or the float 120, each plate having an eyelet which has different heights due to the different height of the plate.

[0041] In particular, the design with two floats 122, 123 provides a safeguard in case one float 122, 123 jams, so that at least 50% of the discharge capacity can still be guaranteed.

[0042] The contact areas 121 are arranged on the float 120 such that a lever arm 111 that is as long as possible can be provided for the vent valve 110, wherein, additionally or alternatively, the respective contact area 121 is arranged closer to a center of gravity of the float 120 than to an outer edge of the float 120.

[0043] In the present embodiment, the four vent valves 110 are arranged parallel to one another, with adjacent vent valves 110 being arranged such that they open opposite each other. In particular, adjacent vent valves 110 each contact a different float 122, 123.

[0044] For example, the lever arm can have a length l in the range of 50–90 mm, preferably 70 mm. Additionally or alternatively, the float 120 or the float bodies 122, 123 can have a height h of 40–60 mm, preferably 50 mm.

[0045] Fig. Figure 2 shows a schematic representation illustrating a first embodiment of the vent valve 200, wherein in the upper area of ​​the Fig. 2 a vent valve 200 is shown in its entirety, and in the lower area of ​​the Fig. 2 A detailed view of a section of the vent valve 200. The vent valve 200 comprises a fixed part 210, a sealing ring 220, a spring 230 and a movable part 240.

[0046] The fixed part 210 of the vent valve 200 is connected to a wall of the automatic air vent in the installed state, with the sealing ring 220 preventing gas or liquid from passing through the vent valve 200 in a closed state. The movable part 240 of the vent valve 200 contacts a contact area 121 of a float 120, so that the movable part 240 moves depending on the liquid level in the gas separator. Relative movement between the movable part 240 and the fixed part 210 is enabled by the spring 230. The exemplary embodiment of the vent valve 200 comprises a lever length of preferably 50–90 mm, particularly preferably 70 mm.

[0047] In the lower area of Fig. Figure 2 of the detailed view of the vent valve 110 also shows a bore with a bore diameter d of the vent valve 200, through which gas or liquid can escape when the vent valve 200 is open. The bore diameter is preferably between 3.2 and 4 mm, particularly preferably 3.6 mm.

[0048] Furthermore, the detailed view of the vent valve 200 shows a distance l2 between a tilting point of the movable part 240 to the fixed part 210 and a center line of the vent valve 200, wherein the distance l2 is preferably 2.4 - 3.2 mm, particularly preferably 2.8 mm.

[0049] Fig. Figure 3 shows a schematic representation illustrating an exemplary embodiment of a floating body from different perspectives.

[0050] In the exemplary embodiment, a floating body 300 is formed with a shape of a longitudinally sectioned half vertical cylinder, as is the case, for example, in the Fig. 1a and Fig. Figure 1b shows the float from three perspectives. Preferably, the float 300 comprises at least one contact area 321 made of two plates that differ in height or by having eyelets of different heights, wherein the contact area 321 is provided on top of the float 300, where "top" corresponds to a side opposite the side of the float that rests on a liquid, i.e., water.

[0051] The contact area 321 can, in particular, comprise two plates, each with an eyelet. In the upper left view of the float 300 in Fig. Figure 3 shows the float 300 from a side corresponding to a flat surface of a circular cylinder, wherein the float 300 has a rectangular surface when viewed from the side. From this side, the two contact areas 310 are preferably arranged next to each other.

[0052] In the upper right view of the float 300 in Fig. Figure 3 shows the float 300 from a different side, the other side corresponding to half of a surface of the float 300. From this side, it can be seen that the contact areas 310 are aligned. Preferably, the height of the float 300 is 40–60 mm, more preferably 50 mm.

[0053] In the lower view of the swimmer in Fig. Figure 3 shows the float 300 from above, with the contact area 310, i.e., the two plates, shown from above as two rectangles. The radius of the semicircle of the float 300 is preferably 30–50 mm, more preferably 40 mm. More preferably, the float 300 comprises at least one cavity, and can thus be referred to as a hollow body.

[0054] Fig. Figure 4 shows a schematic representation to illustrate a second embodiment of the automatic air vent 400.

[0055] The automatic air vent 400 also comprises four air vents 410, each air vent 410 comprising a lever arm 411 with a length l1. The automatic air vent 400 further comprises a float 420, which is formed from two float bodies, each with a contact area 421. Each contact area 421 is configured to contact the contact means of two air vents 410, i.e., to be mechanically connected, at least temporarily. The float 420 thus contacts each air vent 410 in such a way that, when it rests on a liquid, at least one air vent 410, in this case two air vents 410, are opened depending on the liquid's fill level. The automatic air vent 400, and in particular the contact area 421 of each float body, is configured to open the at least two air vents 410 at different fill levels.

[0056] In the present embodiment, the four vent valves 110 are arranged parallel to one another, with adjacent vent valves 110 being arranged such that they open next to each other, i.e., on the same side of the automatic vent 400. In particular, adjacent vent valves 110 each contact the same float 122, 123.

[0057] Furthermore, in the present embodiment, a contact area 421 in the form of a plate with two eyelets for two vent valves 410 of different heights is provided, wherein the height of the plate or the height of the arrangement of the eyelets can be different.

[0058] Fig. Figure 5 shows a schematic representation to illustrate a third embodiment of the automatic air vent.

[0059] The automatic air vent 500 also comprises four air vents 510, each with a lever arm 511, and a float 520. The float 520 comprises two float bodies, each with a contact area 521. In the present embodiment, the contact area 521 is formed from two plates projecting from the upper side of the float, the two plates being arranged on two opposite sides of the float body. Two air vents 510, which contact a float body, are arranged such that they open opposite each other.

[0060] The lever length of the lever arm 511 is given by a length l1 and is preferably 50 - 90 mm, particularly preferably 70 mm.

[0061] The respective automatic air vents in the Fig. 1a, Fig. 1b, Fig. 4 and Fig. 5 can be provided with one float instead of two, whereby contact areas can be provided in each case which are designed so that one, two, three or four vent valves are opened at different fill levels.

[0062] Fig. Figure 6a shows a schematic representation illustrating a fourth embodiment of the automatic air vent from the side.

[0063] The automatic air vent 600 comprises an annular float 620 and three air vent valves 610, which are located in Fig. 6b will be shown from the side.

[0064] Fig. Figure 6b shows a schematic representation illustrating the fourth embodiment of the automatic air vent 600 from above. Fig.Figure 6b shows a radially symmetrical arrangement of the vent valves 610. The float 620 comprises a contact area 621 that contacts each vent valve 610 in such a way that, when it rests on a liquid, it opens the vent valves 610 sequentially, depending on the liquid level. Furthermore, the automatic vent 600, in particular the float 620, is designed to open the three vent valves 610 at different liquid levels. This can be achieved, for example, by a contact area 621 in which the respective contact element of each vent valve contacts the contact area 621 at different heights.

[0065] Even though the figures show various aspects or features of the invention in combination, it is apparent to the person skilled in the art – unless otherwise stated – that the combinations shown and discussed are not the only possible ones. In particular, corresponding units or sets of features from different embodiments can be interchanged.

[0066] Some further considerations regarding the invention follow.

[0067] During the development of a new air-to-water heat pump series using R290 as a refrigerant, the problem was recognized that a defect (for example, a general defect or a defect caused by freezing water) in the plate heat exchanger could allow refrigerant to enter the secondary circuit, i.e., the heating circuit, of the heat pump, which could then enter the house via the distribution system.

[0068] Previously, automatic air vents with large volumes (approximately 10 to 100 times larger than standard heating circuit air vents), large floats, and lever-operated valves were used. Furthermore, these larger automatic air vents were made of brass or stainless steel, which resulted in high costs.

[0069] The object of the current invention is to remove large quantities of gas from the heating system in combination with a gas separator (e.g. cyclone separator) without causing a significant pressure increase in the system.

[0070] To achieve high blow-off capacity in a small installation space, the number of vent valves was increased, for example to 3 or 4, and the valve lever travel was lengthened. Additionally, the float is designed so that the valves are actuated sequentially.

[0071] For added safety, the float can also be divided so that, in case one float were to jam, 50% of the blow-off capacity is still guaranteed.

[0072] A key aspect of the invention lies in implementing the high blow-off performance of the automatic air vent in a small space, which is achieved by reducing the actuating force of the valves, which in turn allows for a smaller design of the float.

[0073] For this purpose, the vent valves, which are actuated by a float, are activated sequentially. This reduces the actuating force on the float. To increase the venting capacity, the gas is released through multiple valves.

[0074] To improve operational reliability, the float can also be designed as two separate floats. This ensures that even if one of the floats jams, 50% of the blow-off capacity is still guaranteed.

[0075] To prevent the float from jamming, the levers of the valves preferably act near the center of gravity of the float.

[0076] Additionally, the automatic air vent can be mounted to the gas separator using a plug-in connector. A shut-off valve can also be installed on the gas separator, allowing the automatic air vent to be replaced without draining the water circuit.

[0077] The features mentioned above allow for a reduction in the size of the gas separator, particularly through an improved lever length and serial actuation of the individual valves. A redundant system (using two floats) is also preferred.

[0078] The new technology can be used in all new heat pump developments that use flammable refrigerants to operate the refrigeration circuit.

[0079] Additionally, the invention can be used in all systems that require increased ventilation performance.

[0080] The invention relates to an automatic air vent for use in a gas separator of a heat pump system, wherein the automatic air vent comprises at least two air vents and a float, wherein each air vent has a lever arm with a contact element, wherein the float has a respective contact area configured to contact the contact element of each air vent, wherein the float contacts each air vent such that, when in contact with a liquid, it opens an air vent depending on the liquid level, and wherein the automatic air vent is configured to open the at least two air vents at different liquid levels. This allows the actuation force of each air vent to be reduced, so that the float, and thus the entire automatic air vent, can be made smaller.

[0081] The outlet openings of the individual valves, at least the valves of the vent, are advantageously brought together in a collecting pipe so that escaping gas and / or any water can be specifically drained via the collecting pipe.

[0082] It is advantageous to have a locking device attached to the manifold, which makes it advantageous to deactivate the venting process.

Claims

[1] Automatic air vent (100, 400, 500, 600) for use in a gas separator of a heat pump system, wherein the automatic vent (100, 400, 500, 600) has at least two vent valves (110, 200, 410, 510, 610) and a float (120, 420, 520, 620), wherein each vent valve (110, 200, 410, 510, 610) has a lever arm (111, 411, 511) with a contact medium, wherein the float (120, 420, 520, 620) has a respective contact area (121, 321, 421, 521, 621) which is designed to contact the contact medium of each vent valve (110, 200, 410, 510, 610), wherein the float (120, 420, 520, 620) contacts each vent valve (110, 200, 410, 510, 610) in such a way that, when it rests on a liquid, it opens a vent valve (110, 200, 410, 510, 610) depending on the liquid level, and wherein the automatic vent (100, 400, 500, 600) is designed to open at least two vent valves (110, 200, 410, 510, 610) at different fill levels. [2] Automatic air vent (100, 400, 500, 600) according to claim 1, wherein the at least two air vents (110, 200, 410, 510, 610) are actuated successively. [3] Automatic air vent (100, 400, 500, 600) according to one of claims 1 and 2, wherein the at least two air vents (110, 200, 410, 510, 610) are arranged on opposite sides of the automatic air vent (100, 400, 500, 600). [4] Automatic air vent (100, 400, 500, 600) according to any of the preceding claims, wherein the automatic air vent (100, 400, 500, 600) comprises three or four vent valves (110, 200, 410, 510, 610). [5] Automatic air vent (100, 400, 500, 600) according to one of the preceding claims, wherein the at least two air vents (110, 200, 410, 510, 610) are arranged at different heights with respect to a height of the float (120, 420, 520, 620). [6] Automatic air vent (100, 400, 500, 600) according to one of the preceding claims, wherein the at least two air vents (110, 200, 410, 510, 610) are arranged laterally on the float (120, 420, 520, 620). [7] Automatic air vent (100, 400, 500, 600) according to one of the preceding claims, wherein the float (120, 420, 520, 620) has at least two floats (122, 123, 300), each of the at least two floats (122, 123, 300) contacting at least one air vent (110, 200, 410, 510). [8] Automatic air vent (100, 400, 500, 600) according to claim 7, wherein the automatic air vent (100, 400, 500, 600) has at least four vent valves (110, 200, 410, 510, 610) and each of the at least two floats (122, 123, 300) is contacted with at least two vent valves (110, 200, 410, 510). [9] Automatic air vent (100, 400, 500, 600) according to one of claims 7 or 8, wherein the float (120, 420, 520, 620) comprises two uniform float bodies (122, 123, 300), each having the shape of a longitudinally cut half vertical cylinder with a semicircular base. [10] Automatic air vent (100, 400, 500, 600) according to one of the preceding claims, wherein the respective contact area (121, 321, 421, 521, 621) of the float (120, 420, 520, 620) is configured to open the at least two vent valves (110, 200, 410, 510) at different fill levels. [11] Automatic air vent (100, 400, 500, 600) according to one of the preceding claims, wherein the contact areas (121, 321, 421, 521, 621) of the float (120, 420, 520, 620) are arranged at different heights with respect to a height of the float (120, 420, 520, 620). [12] Automatic air vent (100, 400, 500, 600) according to one of the preceding claims, wherein the respective contact area (121, 321, 421, 521, 621) comprises at least one plate with at least one eyelet, wherein the plate protrudes from the float (120, 420, 520, 620), in particular upwards. [13] Automatic air vent (100, 400, 500, 600) according to claim 12, wherein the eyelets are arranged at different heights of the plate(s) or the eyelets are arranged at different heights with respect to a height of the float (120, 420, 520, 620). [14] Automatic air vent (100, 400, 500, 600) according to one of the preceding claims, wherein the respective contact area (121, 321, 421, 521, 621) is arranged closer to a center of gravity of the float (120, 420, 520, 620) than to an outer edge of the float (120, 420, 520, 620). [15] Automatic air vent (100, 400, 500, 600) according to one of the preceding claims, wherein the automatic air vent (100, 400, 500, 600) is attached to the gas separator by means of a plug connector. [16] Automatic air vent (100, 400, 500, 600) according to claim 15, wherein the plug connection comprises a shut-off valve. [17] Automatic air vent (100, 400, 500, 600) according to any of the preceding claims, wherein each air vent (110, 200, 410, 510, 610) comprises a fixed part (210), a sealing ring (220), a spring (230) and a movable part (240). [18] Automatic air vent (100, 400, 500, 600) according to any of the preceding claims, wherein the float (120, 420, 520, 620) comprises at least one hollow body. [19] Automatic air vent (100, 400, 500, 600) according to any of the preceding claims, wherein the automatic air vent (100, 400, 500, 600) comprises a safety valve. [20] Gas separator for a secondary circuit of a heat pump system with an automatic air vent (100, 400, 500, 600) according to one of claims 1 to 19. [21] Heat pump system comprising a primary circuit for conveying a refrigerant, a secondary circuit for conveying water, and a heat exchanger for transferring heat between the refrigerant and the water, wherein the secondary circuit comprises a gas separator according to claim 20.

Images