Patent Description:
The prior art discloses a great number of different technical solutions, of varying shapes and designs, aimed at providing natural ventilation of residential and non-residential buildings. The quest to find optimal ventilation system solutions is driven by an attempt to equip a ventilated building in such a way as to provide maximum energy savings and to create a controlled environment within a building. In buildings like these, as a consequence of using central heating and operating domestic appliances, significant drying and contamination of the air inside the building occurs, which in turn creates a suitable environment for the development of allergenic diseases and breathing complications. In springtime and during the summer, energy efficient buildings are not good at removing increased levels of moisture from the air, which makes the natural circulation of air inside a building difficult, as a result creating a suitable environment for the development of fungi and harmful microorganisms.

A ventilation system according to the preamble of claim <NUM> is disclosed in documents <CIT> or <CIT>. Another example for a ventilation system having two flow channels, wherein each of the flow channels has a fan, is provided in <CIT>, disclosing air channels not penetrating each other. This is the simplest way for constructing such a ventilation system. However, such kind of assembling air channels does not allow effective heat exchange between a flow of air extracted from a building and a supply air flow.

<CIT> discloses a decentralized supply and extract unit with waste heat recovery, said unit comprising a recuperative heat exchanger with an air duct, a fan and a heat exchanger, all of which are linked to each other and can be built into the wall of a building, between the external and internal surfaces of said building, a corrugated heat exchanger, Ω-shaped in cross-section, being used as the heat-exchange element, at both ends of which an external fan and an internal fan are fitted.

<CIT> also discloses a heat exchanger for the purpose of heat transfer, carried out between two fluid mediums, wherein this heat exchanger is in the form of a round ring cylinder, and the heat-exchange elements are located around the axis of the cylinder, and are adjacent to each other, wherein the path along which the fluid medium travels into the counter-current flow zones and co-current flow zones in the heat exchanger, runs parallel with the axis of the cylinder, wherein the fluid mediums are set in motion by means of two fans, located at the end surfaces of the heat exchanger. The flow diagram of this heat-exchange device is shown in <FIG>. The heat exchanger <NUM>, in the form of a round ring cylinder, has two opposing end surfaces, each of which is divided into an external zone <NUM> and an internal zone <NUM>, which are hydraulically separated from one another. A fan <NUM> and a fan <NUM> are located in the internal zones <NUM>, the axes of which fans run parallel with the axis of the heat exchanger <NUM> and are located on this axis. Therefore, the fans <NUM> and <NUM>, in this design, are located in annular collars <NUM> and <NUM> which run parallel with the axis <NUM> of the cylinder and are located on this axis. Moreover, if the temperature outside a building is significantly higher than the temperature inside that building, such geometrical positioning of at least the internal fan results in the formation of high levels of condensate which can ingress into the building. This is also true for the reverse situation, i.e. when the temperature outside the building is significantly lower than the temperature inside the building, which results in excessive dropout of condensate and can result in the formation of ice. Furthermore, dividing the end surface of the heat exchanger <NUM> into an external zone <NUM> and an internal zone <NUM>, where flows are moving in opposite directions, results in an increase in resistance of the flow of air passing through the heat exchanger, which in turn results in increased noise levels when the heat-exchange device is operating, to increased power consumption and a higher wear rate of the fans.

The aim of the claimed invention is to reduce levels of condensate formation during operation of a decentralized supply and extract unit with waste heat recovery. This aim is achieved by means of the decentralized supply and extract unit with waste heat recovery defined in claim <NUM>. The preferred embodiments of the invention are defined in the dependent claims.

The claimed ventilation unit is designed to be installed into an external wall of a building and has an indoor module located on the inside of the wall of the building and a heat-exchange module adjoining said indoor module. The heat-exchange module moreover comprises a cylindrical corrugated heat exchanger with a plurality of cross-sectionally similar heat-exchange air ducts, which are located along the axis of symmetry of said heat exchanger and are located adjacent to each other, forming a continuous corrugated volume of heat-exchange elements. Furthermore, the unit comprises a first separator and a second separator for separating and directing extraction and supply air flows in opposite directions in the heat-exchange air ducts, wherein the first separator and the second separator adjoin the heat exchanger at both end surfaces thereof and are installed on the axis of symmetry of said heat exchanger. Furthermore, the unit has a first fan and a second fan, the fan units of which adjoin the first separator and the second separator respectively, at the ends of the separators facing away from the heat exchanger, wherein the axis of one of the fans is located parallel with the axis of the other fan but is not aligned with the latter. As a consequence, both fans can be in opposing positions, relative to the heat exchanger, behind the separators, but not be in alignment with to each other.

According to the present invention, the first separator and the second separator are elements which are independent of the heat exchanger, which makes it possible to simplify manufacture and maintenance of the heat exchanger itself. Furthermore, this solution enables the same separators to be used with heat exchangers of different lengths depending on the thickness of the wall into which the unit is being built. Moreover, the total cross-sectional area of the first separator and the second separator preferably corresponds to the total cross sectional area of the heat exchanger, while the separators contain channels which are an extension of the air ducts of the heat exchanger, forming, together with the air ducts, a continuous volume, which is corrugated in shape and which enables the supply and extraction air flows to move freely, i.e. with the least resistance, from one separator to the heat exchanger, and then on to the other separator. According to the invention, the first separator and the second separator have external end holes facing away from the heat exchanger, every second external end hole being completely closed off, and internal distribution holes facing towards the axis of symmetry of the heat exchanger, every second internal distribution hole being completely closed off and being offset by one spacing of channels, relative to the external end holes. This particular design of separator determines the compactness and operational functionality of the separators, as a result of which the entire external end surface of the separator, directed away from the heat exchanger, is used for the passage of the supply and, respectively, extraction air flows, unlike the known prior art illustrated in <FIG>, where the end surface is divided into an external zone <NUM> and an internal zone <NUM>. In the proposed invention the entire end surface of the separator corresponds to the external zone <NUM> illustrated in <FIG>, while the surface of the separator facing the axis of symmetry of the base, on which surface the internal distribution holes are located, corresponds to the internal zone <NUM> illustrated in <FIG>. Preferably, the distribution holes of the separator are located along the axis of the cylindrical surface, perpendicular to the plane on which the external holes of the separator are located. This solution makes it possible to significantly reduce resistance to the supply and extraction air flows when compared to the known prior art.

According to one of the embodiments of the invention, the heat-exchange module comprises a base, in the form of a tubular element, with an axis of symmetry which is aligned with the axis of symmetry of the heat exchanger, and an external casing, which is also in the form of a tubular element, said external casing being concentrically located on the outside of the base, wherein the corrugated heat exchanger, in the form of a round ring cylinder, is located between the base and the external casing and acts as counter-flow recuperative heat exchanger. Preferably, the axis of at least one of the fans should be located parallel with and above the axis of symmetry of the heat exchanger, when the unit is in its mounted position in the external wall of a building. It has been determined, by means of experimentation, that this type of offsetting of the axis of a fan, relative to the axis of symmetry of a heat exchanger, reduces levels of condensate formation. This occurs by virtue of a change in the relationship between cross-sectional areas of air flows coming into the fan from the direction of the heat exchanger, in the upper part and the lower part of said air flows, as a consequence of which the dynamics of these air flows also changes, when compared to the scenario when the axis of the fan is located on the axis of symmetry of the heat exchanger. As a result of offsetting the axis of at least one of the fans relative to the axis of symmetry of the heat exchanger, the zone of high condensate formation is reduced in size when said fan draws in cold air. In the event that condensate still forms, the amount of condensate able to ingress into the fan (and consequently, into the building, in the case of an internal fan) reduces by virtue of the altered geometry of the fan housing, which is offset relative to the axis of symmetry of the heat exchanger.

The preferred design of separator channels is where said channels are located in the separator in such a way that they form a geometrical prolongation of the air ducts of the heat exchanger, along the entire length of the corresponding first separator and second separator. Positioning the channels of the separators in such a way, relative to the air ducts of the heat exchanger, makes it possible to additionally minimize resistance to the movement of the supply and extraction air flows.

When designing the cross section of the end holes of the separators to correspond to the cross section of the air ducts of the heat exchanger, the dynamic resistance of the supply and extraction air flows passing through the separators is additionally minimized when the condition of maximum compactness of the shape of the separators themselves is met.

According to another embodiment of the invention, the separators may be manufactured from a plastic material and have separator channels which have an aerodynamic profile designed to reduce resistance to the air flow passing through these channels, ensuring smooth inflow and outflow of air into (out of) the heat exchanger, which reduces the aerodynamic resistance of the unit overall and has a positive effect on reducing aerodynamic noise and consumed power. Separators manufactured of plastic significantly reduce condensate levels, reducing the risk of the unit icing up from the inside and the appearance of ice formations on the outside. Also, the material of the separators, in reducing condensate levels, minimizes the formation of ice on the surface of the heat exchanger, ensuring the efficiency of the heat exchanger and aerodynamic characteristics remain constantly high, thus improving the operating characteristics of the unit as a whole.

According to one of the embodiments of the invention, at least the first of the fans is installed in a housing which broadens out in a direction away from the corresponding separator, said housing having an inner tubular element adjoining an inner, i.e. located at the axis-of-symmetry end of the heat exchanger, edge of the external end holes of the corresponding separator, and an outer tubular element having a greater diameter than the inner tubular element. Moreover, the fan itself is located in the outer tubular element of the housing, while the position of the axis of symmetry of the outer tubular element of the housing of this fan is offset, parallel with the axis of symmetry of the inner tubular element of the housing of this fan. Moreover, the fan may be only partially located in the outer tubular element of the housing and may partially protrude from said outer tubular element of the housing, at the end lying opposite to the inner tubular element, correspondingly lying opposite the heat exchanger. The preferred location of the axis of symmetry of the outer tubular element of the housing of this fan is above the axis of symmetry of the inner tubular element of the housing of this fan when the unit is in its mounted position in the external wall of the building.

According to one of the embodiments of the invention, a tubular adaptor element is located between the outer and inner elements of the fan housing, said tubular adapter element preferably having a conical shape, tapering outwards in a direction away from the heat exchanger. This shape of fan housing is the most aerodynamic, and correspondingly, presents the least resistance to the air flow passing through this housing. The shape of the inner, outer and adapter elements of the fan housing may, in cross section, be round, oval or in the form of a polyhedron. Depending on the degree of offset of the axis of symmetry of the outer tubular element of the housing, relative to the axis of symmetry of the inner tubular element of this housing, the bottom line of intersection of the adapter element and the plane which runs through the axes of symmetry of the outer and inner tubular elements may be located either diverging in a direction away from the inner tubular element, towards the outer tubular element, relative to the axis of symmetry of the inner tubular element, or parallel with same, or converging in this direction. In the second and last abovementioned cases, when this line of intersection is located in the bottom part of the entire fan housing, when the unit is in its mounted position in the external wall of a building, the ingress of condensate, forming in the fan housing, into the outer tubular element of the fan housing, will be prevented, or be significantly reduced by virtue of the force of gravity acting on the condensate as it forms. In this embodiment of the invention, the axis of symmetry of the inner tubular element of the fan housing is in alignment with the axis of symmetry of the heat exchanger or is located parallel with same. In this embodiment of the invention, it is preferable to offset the axis of symmetry of the outer tubular element of the housing relative to the axis of symmetry of the inner element of the housing, for the first of the fans, i.e. the fan installed on the inside of the building, i.e. on the side of the internal premises. However, the design variant of this housing is also possible for a fan located outside a building, or for both fans.

According to another embodiment of the proposed invention, the axis of the first fan, located inside the wall of a building, is located in parallel with and above the axis of symmetry of the heat exchanger, when the unit is in its mounted position in the external wall of the building. This embodiment of the invention makes it possible to reduce the level of condensate formation in the section of the unit located closer to the inside of the wall of the building, relative to the heat exchanger. This solution results in the minimisation or elimination of condensate ingress into a ventilated building.

According to another embodiment of the invention, a breakout board chassis is fitted in the inner tubular element of the base of the heat-exchange module for the purpose of controlling operation of the unit, wherein the first separator and the second separator are fixed to the end surfaces of the chassis, while the chassis has a round baffle plate which transversely closes off the inner tubular element of the base. Said round baffle plate may be fixed either to one end surface of the chassis, or also to any section of the chassis between the end surfaces thereof. Alternatively, two round baffle plates, transversely closing off the inner tubular element of the base, can be fixed to the end surfaces of the chassis. Closing off the inner tubular element of the base is necessary in order to direct the supply and extraction air flows through the air ducts of the heat exchanger, correspondingly to prevent these flows from passing through the inner tubular element of the base. Such a chassis arrangement in the inner tubular element of the base allows the chassis to be used as a clamping device, to both ends of which the first separator and the second separator are fixed. If the length of the heat exchanger needs to be altered due to the thickness of the building wall into which the unit is being built, the total length of the base and the chassis is selected based on the required length of heat exchanger. Furthermore, the heat generated during operation of the chassis-mounted breakout board may be effectively used to heat the heat exchanger. All the connections on the boards (not shown) are provided with the aid of plug-and-socket connectors, without using bulky terminal blocks and unwieldy cable runs, which improves connection reliability and saves internal space for the unimpeded passage of air.

At low outside temperatures, a heating element can be used for additional heating of the air, said heating element being fitted between the heat exchanger and the outer casing of the heat-exchange module.

According to one of the embodiments of the invention, an indoor module comprises a housing which has a front and side surfaces, as well as at least one flapper valve for closing off the supply and/or extraction air flows, said flapper valve being located on at least one side surface of the housing. When the unit is not being used, this at least one flapper valve hydraulically separates the indoor space of the building from the internal space of the unit.

As an option, the indoor module may comprise an electronic display to allow for visual control of the unit's operation, wherein the electronic display is fitted to the front surface of the housing of the indoor module, which provides an ergonomic way to control the operation and monitor the parameters of the unit during operation.

According to another embodiment of the invention, the indoor module comprises an angled baffle plate for altering the direction and separation of the supply and extraction air flows, directing these flows in opposite directions inside the building, said angled baffle plate being located inside the housing of the indoor module.

It is preferable, in at least one channel formed by the angled baffle plate, to fit an air filter, in order to prevent contaminants, suspended in the airflow, from ingressing into and/or egressing the building.

In order to reduce indoor noise generated by the unit during operation, the indoor module comprises a polymer noise attenuator fitted in the housing thereof. The preferred design of polymer noise attenuator has a cross section corresponding to the cross section of the front surface of the indoor module, but not less than <NUM>%, preferably not less than <NUM>% of the area of said front surface. As an option, the polymer noise attenuator may be used as a filter for the air flows.

According to another embodiment of the invention, an anti-icing heating element, designed to provide protection against icing up of potential condensate, is fitted to the bottom part of the unit, the part which adjoins the outside wall of the building.

According to another embodiment of the invention, the unit is additionally equipped with an external outdoor module, located on the outside of a wall of a building, said outdoor module having an angled front surface, the bottom edge of which stands out further from the external wall of the building than the upper edge, and sides which have holes for supply and extraction air flows. The angled design of the external side of the wall of the outdoor module prevents the ingress of external precipitation into the unit. The preferred location of the holes for supply and extraction air flows is on the opposing side surfaces of the outdoor module.

The attached drawings clearly illustrate the proposed invention, based on embodiments of same, showing:.

The concept of the claimed invention will be disclosed subsequently in more detail, using specific examples of embodiments thereof. This concept, however, may also be implemented in other embodiments of the invention which include only features included in the claims, and which embodiments are not limited by the cited examples. Numbering of reference designations is consistently maintained for all embodiments of the invention.

As already indicated above, <FIG> illustrates the vertical cross section through the heat-exchange device known from the prior art, in which device the axes of both fans, located on each side of the heat exchanger, are aligned with the axis of symmetry of the heat exchanger.

<FIG> illustrates the vertical cross section of one of the embodiments of the claimed invention. The claimed decentralized supply and extract unit with waste heat recovery incorporates a base <NUM> in the form of a tubular element, an external casing <NUM>, in the form of a tubular element, concentrically located on the outside of the base <NUM>, as well as a corrugated heat exchanger <NUM> with an axis of symmetry <NUM>, said corrugated heat exchanger being located between the base <NUM> and the external casing <NUM>. The axes of symmetry of the base <NUM> and the external casing <NUM> are preferably in alignment with the axis of symmetry <NUM> of the heat exchanger <NUM>. An embodiment of the heat exchanger <NUM>, with first and second separators <NUM>, <NUM> adjoining the end surfaces of same, is illustrated in perspective in <FIG>. Heat exchanger <NUM> has a plurality of heat-exchange air ducts <NUM>, located along the axis of symmetry <NUM> of the heat exchanger, said air ducts being cross-sectionally similar and being located adjacent to each other, forming a continuous corrugated volume of heat-exchange segments. The heat exchanger <NUM> is in the form of a round ring cylinder, the length of which corresponds to the length of the base <NUM>. The shape of the air ducts <NUM> of the heat exchanger <NUM>, may be either straight or wavy along the length of said air ducts as shown in <FIG>, which makes it possible to convert the dynamic air flow in the air ducts <NUM> from a laminar flow into a turbulent flow, at the same time improving the transfer of thermal energy by mixing air in the compartments of the heat exchanger, which in turn leads to an increase in heat-exchange efficiency between the supply and extraction air flows, <NUM>, <NUM>. A first separator and a second separator <NUM>, <NUM> are located along both end surfaces of the heat exchanger <NUM>, the purpose of said separators being to separate and direct extraction and supply air flows <NUM>, <NUM> in opposite directions in adjoining heat-exchange air ducts <NUM>. The first separator and the second separator <NUM>, <NUM> are preferably in the form of a round ring cylinder, the cross-sectional area of which corresponds to the cross-sectional area of the heat exchanger <NUM>. Each of the separators <NUM>, <NUM> contains channels <NUM>, illustrated in <FIG>, said channels being an extension of the air ducts <NUM> of the heat exchanger <NUM>, forming, together with the air ducts <NUM>, a continuous volume of corrugated shape. Each of the first and second separators <NUM>, <NUM> has external end holes <NUM>, facing away from the heat exchanger <NUM>, every second end hole being completely closed off, as illustrated in <FIG>. In addition, each of the first and second separators <NUM>, <NUM> comprises internal distribution holes <NUM>, directed towards the axis of symmetry <NUM> of the heat exchanger, every second distribution hole being completely closed off and being offset by one spacing of channels of the separator <NUM>, relative to the external end holes <NUM>. Preferably, the internal distribution holes <NUM> of the separators <NUM>, <NUM> are located on the inner surface of each of the separators <NUM>, <NUM> which are in the form of a round ring cylinder, as is shown in <FIG>. Therefore, each of the channels of the separator <NUM>, in the case of channels which are adjacent to each other, has, alternately, an external end hole <NUM> and an internal distribution hole <NUM>, in a direction around the axis of symmetry of each of the separators <NUM>, <NUM>. The axis of symmetry of each of the separators <NUM>, <NUM> preferably coincides with the axis of symmetry <NUM> of the heat exchanger.

Furthermore, as illustrated in <FIG>, breakout-board chassis <NUM>, illustrated separately in <FIG>, is located in the base <NUM>. A breakout board <NUM>, with an electronics module, is located on breakout-board chassis <NUM>, and in addition, a round baffle plate <NUM> is located on one of the end sections of the chassis <NUM>. The length of the chassis <NUM> corresponds to the length of the base <NUM> and can vary depending on the thickness of the wall into which the device is built, together with the length of the base <NUM> and the length of the heat exchanger <NUM>. The size of the baffle plate <NUM> corresponds to the internal diameter of the base <NUM> and closes off the base <NUM> completely, at the end surface thereof, preventing air flows from passing through the internal aera of the base <NUM>. The chassis <NUM> acts as a clamping device for the separators <NUM>, <NUM>, which are fixed to the opposing end surfaces of the chassis <NUM> and are installed on base <NUM>. Alternatively, each of the separators <NUM> and <NUM> may be fixed to the base <NUM> and/or to the external casing <NUM>, rather than to the opposing end surfaces of the chassis <NUM>. Alternatively, the breakout board <NUM>, together with the chassis <NUM> thereof, may be fitted in any other location of the device, for instance in the indoor module <NUM>.

As shown in <FIG>, which illustrate a horizontal cross section through the ventilation unit, the unit comprises a first fan and a second fan <NUM>, <NUM>, the housings <NUM>, <NUM> of which adjoin the first separator and the second separator <NUM>, <NUM>, at the ends of the separators directed away from the heat exchanger <NUM>. In the embodiment of the invention illustrated in <FIG>, each of the fans <NUM> and <NUM> is fitted in a housing <NUM>, <NUM> which broadens out in a direction away from the corresponding separator <NUM>, <NUM>, said housing having an inner tubular element <NUM>, which adjoins the inner edge, i.e. the edge located at the axis-of-symmetry <NUM> end of the heat exchanger, of the external end holes <NUM> of the corresponding separator <NUM>, <NUM>, and having an outer tubular element <NUM> which has a greater diameter than the inner tubular element <NUM>. A tubular adaptor element <NUM>, which in this embodiment is conical in shape, is located between the inner tubular element <NUM> and the outer tubular element <NUM>. Here it is worth noting that the housings <NUM>, <NUM> of the fans may not necessarily have a tubular adaptor element, as illustrated in the case of the housing <NUM> of the second, i.e. outer, fan <NUM> in <FIG>, which illustrates an exploded view of the main elements of the unit. In the embodiment of the invention illustrated in <FIG>, the housing <NUM> of the first, i.e. the inner fan <NUM>, is manufactured in such a way that the first fan <NUM> itself is located in the outer tubular element <NUM>, while the axis of symmetry of the outer tubular element <NUM> is located above the axis of symmetry of the inner tubular element <NUM>, when the unit is in its mounted position in the external wall of a building. In this embodiment of the invention, the bottom line of intersection of the tubular adaptor element <NUM> and the plane which runs through the axes of symmetry of the outer and inner tubular elements <NUM>, <NUM>, is positioned at a gentler incline i.e. having a lesser angle to the horizontal, than the upper line of intersection of this tubular adaptor element <NUM> in this same plane. This makes it possible to prevent, or to significantly reduce, the ingress of condensate, forming in the housing of this fan, into the outer tubular element of the housing of the fan <NUM>, and consequently, into a ventilated room, when the supply air flow <NUM> moves from the outside to the inside via the first fan <NUM>. In the embodiment of the invention illustrated in <FIG>, only the first of the fans <NUM> has a housing <NUM>, the axis of symmetry <NUM> of the outer tubular element <NUM> of which housing does not coincide with the axis of symmetry <NUM> of the heat exchanger, in this case the axis of symmetry of the housing <NUM> being located above the axis of symmetry <NUM> of the heat exchanger. A similar design is also possible for the second fan <NUM> alone, or for both fans <NUM> and <NUM>.

<FIG> illustrates the end view, looking onto the first separator <NUM> and the part of the heat exchanger <NUM> adjoining said first separator. The shape of the first separator <NUM> is particularly clearly illustrated here, as a round ring cylinder which has in effect exactly the same cross section as the cross section of the heat exchanger <NUM>. The external end holes <NUM> of the first separator <NUM> are located effectively at an angle of <NUM> degrees relative to the internal distribution holes <NUM> of the first separator <NUM>, so that the plane in which each of the internal distribution holes <NUM> is located proves to be parallel with the axis of symmetry <NUM> of the heat exchanger <NUM>.

<FIG> illustrates the cross section E-E, according to <FIG>, from which it can be seen that the cross section of the end holes <NUM> corresponds to the cross section of the air ducts <NUM> of the heat exchanger <NUM>, while the channels <NUM> of the separator <NUM> are a geometrical extension of the air ducts <NUM> of the heat exchanger <NUM>.

<FIG> depicts a partial illustration of the vertical cross section shown in <FIG>, with the first separator <NUM> and part of the heat exchanger <NUM>, said partial illustration providing clarification of the illustrations in <FIG>. Arrows <NUM> and <NUM> denote the extraction and supply air flows respectively. The design of the second separator <NUM> is identical to the design of the first separator <NUM>, the only difference being that the installed position of the second separator <NUM> is turned around by <NUM>° relative to the first separator <NUM>.

<FIG> shows a perspective view of one of the embodiments of the claimed invention, with partially exploded elements of the housing of the indoor module <NUM>, which adjoins the heat-exchange module <NUM>. An external outdoor module <NUM> adjoins the reverse side of the heat-exchange module <NUM>, said external outdoor module having sides <NUM> with holes <NUM> for supply and extraction air flows. The indoor module <NUM> comprises a housing <NUM> which has a front <NUM> and side <NUM> surfaces, as well as flapper valves <NUM>, located on both side surfaces <NUM> of the housing of the indoor module, the purpose of said flapper valves being to close off the supply and/or extraction air flows <NUM>, <NUM>. The indoor module contains an angled baffle plate <NUM>, illustrated in <FIG>, for separating the supply and extraction air flows <NUM>, <NUM>. An air filter <NUM>, illustrated in <FIG> and <FIG>, is fitted in the channels formed by the angled baffle plate <NUM> for the supply and extraction air flows.

According to one of the embodiments of the invention, the indoor module <NUM> comprises a polymer noise attenuator <NUM> fitted in the housing <NUM> of the indoor module, said noise attenuator facilitating a reduction in the operating noise of the unit. An electronic display <NUM>, for controlling and monitoring operation of the claimed device, is located on the front surface <NUM> of the housing of the indoor module <NUM>.

Claim 1:
Decentralized supply and extract unit, with waste heat recovery, designed to be mounted into the external wall of a building, said decentralized supply and extract unit having an indoor module (<NUM>) and, adjoining thereto, a heat-exchange module (<NUM>), comprising
- a cylindrical heat exchanger (<NUM>) with a plurality of heat-exchange air ducts (<NUM>), located along the axis of symmetry (<NUM>) of said heat exchanger, said air ducts being cross-sectionally similar and adjoining each other, forming a continuous corrugated volume of heat-exchange segments,
- a first separator and a second separator (<NUM>, <NUM>) for separating and directing extraction and supply air flows (<NUM>, <NUM>) in opposite directions in heat-exchange air ducts (<NUM>), wherein the first separator and the second separator (<NUM>, <NUM>) adjoin the heat exchanger (<NUM>), at both end surfaces thereof, and are installed on the axis of symmetry (<NUM>) of same,
- a first fan and a second fan (<NUM>, <NUM>), housings (<NUM>, <NUM>) which adjoin the first separator and the second separator (<NUM>, <NUM>) respectively, at the ends of the separators facing away from the heat exchanger (<NUM>), and wherein the axis (<NUM>) of one of the fans (<NUM>, <NUM>) is located parallel with the axis of the other fan (<NUM>, <NUM>) and is not aligned with said axis,
characterized in that the cylindrical heat exchanger (<NUM>) is corrugated;
wherein the first separator and the second separator (<NUM>, <NUM>)
- are designed as separate elements from the heat exchanger (<NUM>),
- have a total cross section which corresponds to the total cross section of the heat exchanger (<NUM>),
- contain channels (<NUM>), which are an extension of the air ducts (<NUM>) of the heat exchanger (<NUM>), forming, together with the air ducts (<NUM>), a continuous volume which is corrugated in shape,
- have external end holes (<NUM>), facing away from the heat exchanger (<NUM>), every second external hole being closed off completely, and
internal distribution holes (<NUM>), facing towards the axis of symmetry (<NUM>) of the heat exchanger (<NUM>), every second hole being closed off completely and being offset by one spacing of channels of the separator (<NUM>), relative to the external end holes (<NUM>).