Moisture management and condensate drain for a heat pump housing

Abstract

Device for moisture management in the encapsulated inner casing (1, 11) of a heat pump, in which a closed, hermetically sealed working fluid circuit is maintained, the refrigeration circuit (15) of which is operated with a flammable refrigerant and which includes at least one compressor, and wherein the heat pump is intended for installation in an interior space of a building, and comprises a casing (10) which, although closed, is permeable to air through a sorption filter (14), wherein, for the removal of liquid and refrigerant vapor from the casing (10) of the heat pump in which the encapsulated inner casing (11) is arranged, a collection form (3, 20) is provided, which closes off the encapsulated inner casing (11) at the bottom, the collection form (20) opens via an opening (5, 21) into a collection volume (23), a liquid detection device is provided in this collection volume (23), and a siphon is provided at the collection volume (23). (26,43) is provided with an outlet valve (25).

Description

[0001] The invention relates to moisture management and condensate drainage from a heat pump housing of a heat pump installed inside a building, which is equipped with an encapsulated refrigeration circuit. An encapsulated refrigeration circuit is defined as an inner housing containing the refrigerant-carrying devices.

[0002] When using a flammable refrigerant, such as R290, R32, R1270, R600a, or R454C, a housing must be used that ensures no flammable refrigerant can escape into the installation room. These heat pump housings are typically not pressure-tight but are designed to "breathe," allowing for air pressure fluctuations. In many cases, this air exchange occurs through a filter, such as an adsorber. This filter is permeable to ambient air in both directions, including humidity, and is intended to prevent flammable refrigerants from escaping into the installation room.

[0003] However, there are limitations to these adsorptive filters, which is related to the fact that heat is generated during adsorption, temporarily reducing the capacity of the adsorbent. If the adsorption system were designed to handle all conceivable leaks despite the heat, a very large quantity of adsorbent would be required. This is especially true since ingress of moisture also reduces the capacity of the adsorbent.

[0004] Therefore, the use of a pressure-tight housing is advisable for safety reasons. In the rare event that refrigerant escapes from the closed heat pump circuit into the pressure-tight housing, pressure would build up within this housing, and the flammable refrigerant could be released in portions so that it is either slowly subjected to sorptive separation or can be vented to the outside outside the building.

[0005] Therefore, a pressure-tight inner casing is provided within the heat pump housing. A ventilation opening is connected to this pressure-tight inner casing and a sorption bed. This connection can be direct or via a pipe. The sorption bed can be located either within the heat pump housing, which surrounds the pressure-tight inner casing, or outside the heat pump housing as a separate sorption bed. The connecting pipe, if present, should be closable and equipped with a pressure reducer.

[0006] Within the pressure-tight inner casing, one or more safety valves are provided that activate in case of overpressure. The use of heat transfer fluids carries the risk that, under certain pressure conditions, leaks could allow the refrigerant to enter the heat transfer fluid via the heat exchangers. This can occur if the heat transfer fluid has a lower pressure at the leak site than the refrigerant, resulting in a pressure build-up within the heat transfer fluid. This primarily affects the warm side of the refrigeration circuit, as the compressor generates the pressure, which is then present in the condenser heat exchanger. From there, a leak can allow pressurized refrigerant to enter the heat transfer fluid.This pressure increase in the heat transfer fluid circuit then causes the safety valves in the pressure-tight inner housing to open, which can further result in large quantities of warm heat transfer fluid being introduced into the pressure-tight inner housing along with the refrigerant. Depending on the pressure and temperature, this can then lead to flash evaporation. Water and brine are typically used as heat transfer fluids in this process.

[0007] The problem here is that the heat transfer fluids should not enter the sorptive filter, as this would reduce the filter's separation capacity for the refrigerant; therefore, gas-liquid separation is necessary. On the other hand, refrigerant components dissolved in the heat transfer fluid, which have entered the pressure-tight inner housing via safety valves, should not escape as dissolved components in the liquid phase and be able to degas uncontrollably at an unfavorable location.

[0008] DE 10 2019 114 738 A1 describes a heat pump with a refrigeration circuit and an adsorber arranged laterally on the outside of the casing. This adsorber acts as both an adsorbent for potentially refrigerant-contaminated air and an absorber for structure-borne noise, and air can flow through the adsorber from bottom to top. Potential condensation is not considered.

[0009] Humidity can also condense on cold surfaces inside the heat pump casing, and it can enter the pressure-tight inner casing via the sorption filter. With conventional adsorbents, there is a risk that the moisture will condense on the adsorbent and impair its ability to absorb any refrigerant that may have leaked out. Furthermore, condensate can also escape through air separators or other safety valves.

[0010] This contrasts with the requirement for reliable condensate drainage, where condensate, which typically accumulates during operation, must be safely removed from the heat pump casing and the pressure-tight inner casing, while at the same time no refrigerant may escape in the event of a leak. Furthermore, the condensate should not come into contact with the adsorbent.

[0011] US Patent 2005 / 0005625 describes an automatic drainage device for an air conditioner. The drainage device includes a condensate collection tank and a siphon. The inlet to the siphon is located in the collection tank, and the outlet is situated outside the building at a lower elevation. When a certain water level is reached in the collection tank, a pump is briefly activated to fill the siphon. The collected water then drains away according to the principle of communicating vessels, without the pump remaining active. However, neither document explains how gas-liquid separation could be achieved simultaneously.

[0012] WO 2010 / 062923 A1 teaches how, for a vehicle, refrigerant whose vapor is heavier than air can be detected from a leak in an air conditioning system by means of a sensor and discharged via a drain opening in the sump of the air conditioning system.

[0013] EP 3 988 858 A1 teaches how to seal the exhaust gas chamber of a condensing boiler from the installation room. For this purpose, a drain is created from a condensate collection tank via a float with a closing function.

[0014] According to conventional technology, such condensate drainage occurs via an opening or a hose. For example, KR 10 2007 0053 835 A describes such a condensate drainage system for an air conditioner, although this system does not use a capsule housing. Instead, the room air is passed directly through the refrigerant-carrying heat exchanger, thus ignoring the issue of flammable refrigerant. Another condensate drainage system for an air conditioner is described in JP 2012 184 861 A, where a collection tank with an attached condensate pump prevents odors caused by condensation. DE 10 2020 100 806 A1 describes an air-to-water heat pump with an evaporator chamber into which the outlet of a safety valve leads, and in which refrigerant that has leaked out is also collected.The condensate is pumped to the outside via a condensate pump, and any potentially contaminated air is vented to the outside via a duct.

[0015] The condensate is then either drained into the wastewater system or evaporates, and a siphon forms the hydraulic seal. This type of system is found in virtually all refrigerators and air conditioners. However, if a leak of flammable refrigerant were to occur within a sealed heat pump housing, such a simple method of condensate drainage is unacceptable. Even the use of a standard siphon is not safe, as it can dry out or become clogged.

[0016] The object of the invention is therefore to provide a space-saving, safe and economical device in which condensate and leakage-related refrigerant are removed from an encapsulated inner housing of a heat pump.

[0017] The dilemma described above is solved by first redesigning the base plate, on which all the important components are usually mounted within the pressure-tight inner housing. It is now designed as a funnel, incorporates at least one drain, and functions as a condensate collector. Furthermore, it seals off a collection volume located below, which also includes gas separation devices and a siphon protected against drying out. The base plate thus becomes a complex component.

[0018] Specifically, the invention solves the problem by means of a device according to claim 1 for moisture management in the encapsulated inner housing of a heat pump, in which a closed, hermetically sealed working fluid circuit is maintained, the refrigeration circuit of which is operated with a flammable refrigerant and which includes at least one compressor, and wherein the heat pump is intended for installation in an interior space of a building, and comprises a housing which, although closed, is permeable to air through a sorption filter, wherein, for the removal of liquid and refrigerant vapor from the housing of the heat pump in which the encapsulated inner housing is arranged, a collection form is provided which closes off the encapsulated inner housing at the bottom, the collection form opens via an opening into a collection volume, a detection device for liquid is provided in this collection volume, and a siphon is provided at the collection volume.

[0019] A shut-off valve is typically located outside the housing following the siphon. The collection volume can also be positioned externally and connected to the collection form below it via a pressure-tight connection. In this case, it has the same effect as if it were located inside the encapsulated inner housing, but can potentially make better use of available installation space.

[0020] According to the invention, it is provided that in the lower part below the installations of the refrigeration circuit The collection form is designed as a funnel-shaped intermediate plate, either in one or more parts, which covers the entire base area of ​​the encapsulated inner housing; this intermediate plate has at least one incline and at least one opening as a drainage device at the lower end of the incline; the intermediate plate is at least partially gas-permeable on its sides or over its surface, but not liquid-permeable outside the openings as drainage devices.

[0021] The average inclination of the intermediate plate should have a funnel inclination of at least 1 degree, although the inclination may vary.

[0022] Furthermore, according to the invention, it is provided that Each of the openings serves as a drainage device leading into a drainage shaft filled with adsorbent; below the intermediate plate, an upwardly open container with adsorbent is arranged at the top of the collection volume, which is hydraulically connected to the interior of the housing but has no hydraulic connection to the interior of the drainage shafts; the container with adsorbent has an air-permeable opening on its underside that retains the adsorbent; each drainage shaft has a liquid-permeable opening on its underside that retains the adsorbent; below the container with adsorbent and below the drainage shafts, a free space is provided in the collection volume into which air and condensate can be drained.

[0023] It is advantageous if the adsorbent in each drain shaft, in conjunction with the top and bottom openings and the retention device for adsorbent, has a higher flow resistance than the container with adsorbent in conjunction with its top and bottom openings and its retention device for adsorbent on its underside.

[0024] The crucial factor here is the difference in flow resistance between the adsorption bed in the adsorbent container and each drain chamber filled with adsorbent. If the flow resistance in each drain chamber for escaping gaseous refrigerant is greater than that of the path through the adsorption bed, it is ensured that in the event of a leak, the majority of the refrigerant enters the adsorption bed and is adsorbed there. Only a relatively small portion reaches the drain chambers, where it is adsorbed by the adsorbent present there, while the condensate can pass through unimpeded.

[0025] The length of the drain shaft is crucial in comparison to the path a refrigerant-air mixture must take through the adsorbent in the reservoir. If the adsorbents in the drain shaft and the adsorption bed are identical, this means the shaft must be at least as long or as high as the typical adsorbent area. The fill height of the adsorbent in the drain shaft must then be at least the same.

[0026] The design features relate to the adsorbents used to achieve the desired effect. One variant provides for the adsorbents in both the adsorption bed of the container and in each outlet shaft to be a bed of shaped adsorbent particles. To increase flow resistance, a finer particle size can be used in the outlet shaft than in the adsorption bed of the container.

[0027] Instead of or in addition to fill material with molded elements, open-pore tiles or foams coated with adsorbents can also be used. Such open-pore tiles or coated polyurethane foams in the form of sheet elements can also seal off any drain shaft as well as the adsorption bed of the container at the top and / or bottom and fix the fill material, if present. They are also suitable for adjusting the flow resistance by selecting the pore size.

[0028] Such sheet elements are readily available commercially, for example with a thickness of 21 millimeters, a basis weight of 1.3 kg / m³, and an activated carbon layer of 0.55 kg / m³. They can also be manufactured as molded parts to fit the adsorber. Suitable adsorption materials for both loose fill and covered tiles and foams include activated carbon and carbon molecular sieve adsorber compositions based on vinylidene chloride polymer, as described, for example, in EP 3 160 639 B1.

[0029] Further embodiments concern the one- or multi-part intermediate plate. The shaft is open at the top, as is the entire adsorption bed. To prevent the condensate dripping from the refrigeration circuit from falling directly into the adsorption bed filled with adsorbent in the container, it must be collected across its entire surface by a collection device. This task is performed by the one- or multi-part intermediate plate. Its individual parts are inclined so that the dripping liquid is directed by gravity into the drainage channels. They can also feature channels and raised edges to further guide the liquid. The individual parts cover the entire surface except for the drainage shafts. In the case of multi-part intermediate plates, the individual plates overlap and preferably have raised edges to prevent the draining condensate from forming films on the undersides of the plates.The intermediate plate parts can also be designed as funnels, the openings of which point into the drainage shafts.

[0030] Further embodiments concern the drainage shafts. These have an inlet area, an intermediate section filled with adsorbent, and an end piece with a condensate outlet. The inlet area is preferably protected by a retaining grid, which prevents adsorbent from falling out of the shaft or being washed out during transport or in the event of a sudden heavy accumulation of condensate. The end piece is also preferably protected by a retaining grid, which prevents adsorbent from falling out of the shaft or being washed out during transport or in the event of a sudden heavy accumulation of condensate. Below the retaining grid, the end piece can be slotted to allow condensate to escape laterally, and the drainage shafts can also be used as feet to support the heat pump housing. The intermediate section contains adsorbent.

[0031] Further embodiments relate to the container with adsorbent in the collection volume. To prevent adsorbents, such as bulk particles, from falling out or shifting during transport and consequently creating uneven flow conditions, a retention element can be arranged and fixed on the top. This can be a retention sieve or a mesh screen and a nonwoven fabric or open-cell foam. Inside the container, a honeycomb structure can be created from open-cell foam or nonwoven elements, which encloses the bulk particles and directs the flow along predefined flow paths. Preferably, at least one mesh screen is located below the container as an air-permeable opening to allow the refrigerant-free air to escape.

[0032] Further features relate to the detection device for liquid in the collection volume. Alternatively or in combination, this is designed as Float that closes a contact and thus signals a corresponding water level, AC electrodes whose impedance is measured, DC electrodes whose ohmic resistance is measured, moisture sensors in a sorbent bed, moisture sensors in a housing, vibration detector, optical sensor, reflex sensor, ultrasonic sensor, level sensor, radar sensor.

[0033] If a float and a collection screen are used, they can also be structurally connected. This has the advantage that coarse impurities cannot block the float mechanism if the collection screen is a filter element and the float, as a ring or toroidal structure, can float freely outside the filter element.

[0034] If electrodes are used in conjunction with a collection sieve, the sieve can form one electrode and the collection volume the other electrode.

[0035] If a sorbent bed is used, the heat generation can also be measured; for example, zeolite heats up by up to 60 degrees when water is adsorbed, although the heating can take a longer period of time depending on the refrigerant concentration and flow conditions.

[0036] If a vibration detector is used and the funnel-shaped collection tray also vibrates, liquid water significantly dampens the vibration, which is easily measurable. If a collection sieve is used, its vibration also decreases considerably as soon as its underside is immersed in water.

[0037] The term "inner housing" of the heat pump refers to all housing components in which devices that carry refrigerant, or could carry refrigerant in the event of a leak, are arranged. Thus, the heat exchangers may have separate housings, as may the control electronics with their cooling system. Similarly, the entire refrigeration circuit may be contained within a single housing. Housings separate from ventilation devices, housings connected to outdoor units, or housings nested within one another are all considered heat pump housings within the meaning of this invention.

[0038] The inner casing of the heat pump is usually located inside the heat pump housing, which also contains other components such as the electronics, water storage tank, auxiliary heater, switches for summer air conditioning operation and an adsorber for refrigerant.

[0039] Further design considerations concern the siphon. This can be designed as an open labyrinth with a pressure-boosting system during flow. The pressure-boosting system can consist of a particle bed, open-cell foam, or both. The desired flow resistance depends on the overall required airtightness of the encapsulated heat pump housing. If the housing is open to the outside via an adsorber for refrigerant leaks, or sealed by such an adsorber, the pressure-boosting system in the siphon must have a correspondingly higher pressure resistance. If the encapsulation is to be completely airtight, a pressure relief valve must be provided on the siphon, which is matched to the pressure rating of the encapsulation.

[0040] In one embodiment, the siphon is designed so that it cannot be blown empty even in the event of overpressure and also so that it cannot be clogged by particles. Therefore, the siphon is designed as a drain valve. A conical float ensures that the valve only opens when the float cone rises to the top. A sensor in the drain valve's outlet checks for the presence of liquid during opening. This monitoring prevents particles from becoming lodged in the gap between the float cone and the valve cone, which could prevent the valve from closing.

[0041] The invention is explained using the figures Fig. 1 bis Fig. 9 explained in more detail. It shows: Fig. 1 a schematic representation of an encapsulated inner casing of a heat pump with condensate separation, Fig. 2 the container with adsorbent and the drain shafts. Fig. 3 an overview sketch for a heat pump casing with an encapsulated inner casing, Fig. 4 an encapsulated inner casing with external adsorber and siphon, Fig. 5 an encapsulated inner casing with external adsorber and drain valve, Fig. 6 an encapsulated inner casing with an external, pressure-tight collection volume, Fig. 7 a variant of the collection form with collection volume and liquid detection device, Fig. 8 an alternative variant of the collection form with collection volume and liquid detection device, Fig. 9 a further variant of the collection form with collection volume and liquid detection device, Fig. 10 a drain valve acting as a siphon.

[0042] The figures are not to scale; some representations, such as the height of the collection volume or the funnel inclination, are enlarged or distorted for better clarity.

[0043] Fig. 1 Figure 1 shows a schematic representation of a heat pump housing with the condensate separation system according to the invention. The refrigeration circuit housing 1 is an encapsulated inner housing and contains the refrigeration circuit 2, in which condensate is produced and refrigerant can escape in the event of a leak. The condensate is collected on the funnel-shaped intermediate plate 3 and flows through the opening 5, which serves as a drain hole, into the drain shaft 6. From the drain shaft 6, it flows downwards across the bottom, preferably to the outside or via a siphon into a drainage system.

[0044] In the event of a leak in refrigeration circuit 2, a refrigerant-air mixture forms, causing the internal pressure in the refrigeration circuit housing 1 to rise. The refrigerant-air mixture enters the upwardly open container 4, formed by the housing base and its side walls, via the side edges of the intermediate plate 3. Adsorbent 7 is located both in the container 4 and in the drain chute 6, which adsorbs the refrigerant from the refrigerant-air mixture. The air, now free of refrigerant, exits downwards through the grid 8, preferably also to the outside.

[0045] Fig. 2 Figure 1 shows the container 4 for adsorbent and the five drain channels 6. The mesh screen 8 seals the bottom of container 4 to prevent adsorbent from escaping, but keeps it open for air to escape. The drain channels 6 are also filled with adsorbent and have a higher flow resistance to prevent the refrigerant-air mixture from primarily escaping through the drain channels 6 and exceeding the capacity of the adsorbent in the drain channels 6. The feet 9 ensure a free volume below container 4 so that both air can escape through the mesh screen 8 and condensate can escape through the drain channel 6 without obstruction.

[0046] Fig. 3 Figure 1 shows an overview sketch with a heat pump housing 10, an encapsulated inner housing 11, a hot water tank 12, an electronic control unit 13, an adsorber 14, and a refrigeration circuit 15. The refrigeration circuit 15 has at least one compressor 16, an expansion valve 17, a condenser 18, and an evaporator 19. The connections for heating and heat sources, as well as gas separators and safety valves, are not shown but are also located in the encapsulated inner housing 11.

[0047] When liquid drips downwards in the encapsulated inner housing 11, it is collected by the collecting tray 20 and flows along the funnel's incline into the opening 5, which serves as the drain opening. From there, it passes through the collecting sieve 22 into the collecting volume 23. The amount of liquid is measured there by the liquid detection device 24. If the liquid detection device 24 signals that the shut-off valve 25 should be opened, the liquid can drain to the outside via the siphon 26, where it is collected. To facilitate drainage, the collecting tray is briefly vibrated at regular intervals by the vibrating device 27.

[0048] Fig. 4 shows an encapsulated inner housing 11 with an external adsorber 14 and siphon 26. Compared to the one in Fig. 3 The inner housing shown here depicts the safety valves 37, 41, and 42 for the heat transfer fluids 34 and 38. The heat transfer fluids are routed as heating circuit return 38 from the heating circuit pump 39 via the condenser heat exchanger 18 to the heating circuit supply 40, where they are protected against overpressure by the safety valve 41. The brine return 34 is routed from the brine pump 35 via the evaporator heat exchanger 19 to the brine supply 36, where they are protected against overpressure by the safety valve 37. While the separation principle is fundamentally similar, the significantly larger potential volume of liquid must be taken into account during dimensioning. An additional safety valve 42 protects the refrigeration circuit 15.

[0049] Fig. 5 differs from Fig. 4 a drain valve 43, which can handle larger accumulations of condensate. This drain valve 43 consists of an inlet system 45, which filters out any particles, and a receptacle for the float 44, which opens a conical annular gap during a liquid accumulation. Subsequently, a humidity sensor 46 monitors whether liquid is actually draining while the shut-off valve 25 is open. This reliably prevents blow-through and drying out.

[0050] Fig. 6 differs from Fig. 5 by replacing the inner collection volume 23 with an external, separate collection volume 47. The interior of the encapsulated inner housing is connected to the separate collection volume 47 by a pressure-tight connection 48. Otherwise, the devices are identical, which also applies to the subsequently described arrangements of the collection volume 47, analogous to the collection volume 23.

[0051] Fig. 7 Figure 1 shows a variant embodiment of collection form 20 with collection volume 23 and liquid detection device 24, in which a float 28 and a collection screen 22 are used in combination. The float 28 is arranged as a torus around the collection screen 22; when it reaches the upper edge of the collection screen 22, a contact is triggered.

[0052] Fig. 8 Figure 1 shows another embodiment of collection form 20 with collection volume 23 and liquid detection device 24, in which a divided collection sieve 22 is used, into which two electrodes 29 and 30 are integrated. The electrodes can be supplied with either direct or alternating current; the change in resistance indicates whether liquid accumulates between the electrodes.

[0053] Fig. 9 Figure 1 shows another embodiment of collection form 20 with collection volume 23 and liquid detection device 24, in which the collection volume 23 and the siphon 26 are equipped with elements 31 for increasing flow resistance. The elements 31 are positioned in an open labyrinth, and the shut-off valve 25 remains open. A humidity sensor 32 and a temperature sensor 33, encased in zeolite, are located between the elements 31 to detect moisture. The elements 31 for increasing flow resistance also replace the collection screen 22 when they are made of open-pore foam.

[0054] Fig. 10Figure 1 shows a drain valve 43 acting as a siphon. A conical float 44 ensures that the valve only opens when the float cone rises to the top. This opens an annular gap, indicated by arrows, through which liquid can flow. The liquid flows into the drain valve 43 through a grid 45 at the top. The grid 45 acts as a particle filter. A sensor 46 in the drain valve's outlet monitors the presence of liquid or its flow during opening. This monitoring prevents particles from forming and becoming lodged in the gap between the float cone and the valve cone, which could prevent the valve from closing. Reference symbol list

[0055] 1 Refrigeration circuit housing 2 Refrigeration circuit 3 Intermediate plate 4 Tank 5 Opening as drain hole 6 Drain shaft 7 Adsorbent 8 Grid 9 Unit base 10 Heat pump housing 11 Encapsulated inner housing 12 Hot water tank 13 Electronic control 14 Adsorber 15 Refrigeration circuit 16 Compressor 17 Expansion valve 18 Condenser 19 Evaporator 20 Collection tray 22 Collection strainer 23 Collection volume 24 Liquid detection device 25 Shut-off valve 26 Siphon 27 Vibration device 28 Float 29 Electrode 30 Electrode 31 Elements for increasing flow resistance 32 Humidity sensor 33 Temperature sensor 34 Brine return 35 Brine pump 36 Brine supply 37 Safety valve 38 Heating circuit return 39 Heating circuit pump 40 Heating circuit flow 41 Safety valve 42 Safety valve refrigeration circuit 43 Drain valve 44 Float 45 Inlet system 46 Liquid sensor 47 Separate collection volume 48 Pressure-tight connection

Claims

1. Device for moisture management in the encapsulated inner housing (1, 11) of a heat pump, - in which a closed, hermetically sealed working fluid circuit is maintained, - whose refrigeration circuit (15) is operated with a flammable refrigerant and which comprises at least one compressor, - and wherein the heat pump is intended for installation in an interior space of a building and comprises a housing (10) which is closed but permeable to air through a sorption filter (14), wherein the device for removing liquid and refrigerant vapour from the housing (10) of the heat pump, in which the encapsulated inner housing (11) is arranged, comprises a collection mould (3, 20) which, when the device is arranged in the housing (10) of the heat pump, closes off the encapsulated inner housing (11) at the bottom, characterised in that the device comprises a collection volume (23), wherein - the collection mould (20) opens into the collection volume (23) via openings (5), - a detection device for liquid is arranged in this collection volume (23), - a siphon (26, 43) enclosed by the device is provided on the collection volume (23), - the collection mould (3, 20) is designed as a funnel-shaped single-piece or multi-piece intermediate plate which, when the device is arranged in the housing (10) of the heat pump, covers the entire base area of the encapsulated inner housing (11), is gas-permeable on its sides or over at least part of its surface , but is not liquid-permeable outside the openings (5), - each of the openings (5) leads into a drain shaft (6) filled with adsorbent (7), - below the intermediate plate (3) at the top of the collection volume, there is an upwardly open container (4) with adsorbent (7), which is hydraulically connected to the interior of the housing but has no hydraulic connection to the interior of the drainage shafts (6), - the container (4) with adsorbent has an air-permeable opening (8) on its underside which retains the adsorbent (7), - each drain shaft (6) has a liquid-permeable opening on its underside which retains the adsorbent (7), - below the container (4) with adsorbent (7) and below the drain shafts (6), there is a free space in the collection volume (23) into which air and condensate can be discharged.

2. . Device according to claim 1, characterised in that the adsorbents in both the adsorption bed of the container (4) and in each drain shaft (6) comprise a bulk filling with shaped bodies made of adsorbents, whereby a finer grain size is used in the drain shaft (6) than in the adsorption bed of the container (4).

3. . Device according to claim 1, characterised in that open-pored tiles or open-pored polyurethane foams in the form of surface elements coated with adsorbents are used as adsorbents.

4. . Device according to one of claims 1 to 3, characterised in that, in the case of multipart intermediate plates (3), the intermediate plate parts (3) have channels and up-stands as guide elements for liquid and can overlap each other.

5. . Device according to one of claims 1 to 4, characterised in that the individual intermediate plate parts (3) are designed as funnels whose openings (5) face the drainage shafts (6).

6. . Device according to one of claims 1 to 5, characterised in that the drainage shafts (6) each have an inlet area, an intermediate section and an end piece, wherein the inlet area and the end piece are each protected by a retaining grid and the intermediate section is filled with an adsorbent.

7. . Device according to one of claims 1 to 6, characterised in that the end pieces of the drainage shafts (6) are each slotted below the retaining grid and allow condensate to escape laterally.

8. . Device according to one of claims 1 to 7, characterised in that a gas-permeable retaining means is fixed to the upper side of the container (4) with adsorbent (7), which is designed as a retaining screen or mesh net or fleece or open-pored foam.

9. . Device according to one of claims 1 to 8, characterised in that a honeycomb structure made of open-pored foam or fleece elements is provided in the container (4) with adsorbent (7), which encloses the bulk particles.

10. . Device according to one of claims 1 to 9, characterised in that a grid net (8) is provided in the container (4) with adsorbent (7) on its underside as an air-permeable opening.

11. . Device according to one of claims 1 to 10, characterised in that the detection device for liquid in the collection volume (14) is alternatively designed as - a float (28) which closes a contact and thus signals a corresponding water level, - alternating voltage electrodes whose impedance is measured, - direct voltage electrodes whose ohmic resistance is measured, - moisture sensors (32) in a sorbent bed, - moisture sensors (32) in the housing, - Vibration detector, - optical sensor, - Reflex sensor, - ultrasonic sensor, - level sensor, - radar sensor, - electrodes (29, 30) in conjunction with a collection screen (22), wherein the screen forms one electrode and the collection volume (23) forms the other electrode, - or a combination thereof.

12. . Device according to one of claims 1 to 11, characterised in that an open labyrinth with a pressure-increasing system (31) is provided as a siphon when flow occurs.

13. . Device according to one of claims 1 to 11, characterised in that a drain valve (43) with a float body (44) and a liquid sensor (46) in the drain is provided as a siphon.

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