EP3098527B1 - Method for operating a ventilation device for an area and corresponding ventilation device - Google Patents

Description

The invention relates to a method for operating a ventilation device for a room, with exhaust air with a specific exhaust air mass flow being taken from the room during a ventilation process by means of the ventilation device and / or outside air being taken from the outside environment with a specific outside air mass flow and being supplied to the room in the form of supply air, wherein an exhaust air relative humidity and an exhaust air temperature of the exhaust air as well as an outside air temperature of the outside air are measured. The invention also relates to a ventilation device.

The ventilation device is preferably used to ventilate and / or air-condition the room. The room is, for example, a living room, but can of course also be of a different nature. In particular, the space is not just to be understood as a single room, although this can of course be the case. The space preferably describes a volume of air in very general terms. This can be present in a single room of a building or house or, alternatively, be distributed over several rooms, in particular the entire building.

The ventilation device can be designed as a decentralized ventilation device or as a central ventilation device, or it can be part of a decentralized ventilation system or a central ventilation system. The ventilation device can serve to remove exhaust air from the room, to supply supply air into the room or both to remove exhaust air and to supply supply air. If the ventilation device is in operation, i.e. if the ventilation process is carried out, the room is also exhaust air taken from the specific exhaust air mass flow. The exhaust air is then preferably supplied to the outside environment in the form of exhaust air. In addition or as an alternative, outside air is taken from the outside environment, this being done with the outside air mass flow determined. The outside air is then fed into the room in the form of supply air.

The air in the air flow from the room to the ventilation device is referred to as exhaust air, while the air discharged from the ventilation device in the direction of the outside environment is referred to as exhaust air. The air in the air flow from the outside environment to the ventilation device is referred to above as outside air, while the air in the air flow from the ventilation device into the room is referred to as supply air. Air present in the room can be referred to as room air.

The exhaust air supplied to the outside environment by the ventilation device has a specific exhaust air mass flow, which preferably corresponds to the exhaust air mass flow. Conversely, the supply air from the ventilation device into the room takes place with a certain supply air mass flow, which preferably corresponds to the outside air mass flow. The exhaust air mass flow and / or the outside air mass flow are determined based on at least one parameter and set on the ventilation device.

The ventilation device preferably has at least one air delivery device, in particular a fan. With the help of the air conveyor, the exhaust air is taken from the room or the outside air is taken from the outside environment. Of course, several Air conveying devices can be provided, for example exhaust air is taken from the room by means of a first of the air conveying devices and outside air is taken from the outside environment by means of a second of the air conveying devices.

The air delivery device or the air delivery devices are now set in such a way that the specific exhaust air mass flow and / or the specific outside air mass flow are present. For example, a control and / or regulation of the air delivery device is provided for this purpose, wherein in particular a speed of the at least one air delivery device serves as the manipulated variable.

For example, from the publication EP 1 878 979 A1 a method for controlled ventilation is known. In order to avoid condensation of moisture from the indoor air and long-term moisture damage and mold formation, the temperatures inside and outside the room as well as the relative humidity inside the room are measured using measuring units. The measurement results are passed on to a control unit where they are evaluated by calculating the maximum permissible relative humidity, which can avoid condensation, taking into account the minimum surface temperature, and comparing it with the measured value. If the measured relative humidity is above the calculated relative humidity, a unit is activated to initiate a ventilation process. The EP 1 878 979 A1 thus discloses a method for operating a ventilation device according to the preamble of claim 1 and a ventilation device according to the preamble of claim 8.

The publication also shows DE 10 2008 044 439 A1 a control device and a method for automatic ventilation of basement rooms, the pamphlet DE 199 52 519 1 a temperature and humidity-dependent fan control as well as the publication DE 10 2011 013 944 A1 a ventilation device with dew point-controlled forced ventilation. It is now the object of the invention to propose a method for operating a ventilation device for a room, which has advantages over the prior art, in particular enables reliable dehumidification of the room.

ein Außenlufttemperaturgrenzwert bestimmt wird, wobei ϑ₁ eine erste Temperaturgröße, x_AB eine aus der Abluftrelativfeuchte und der Ablufttemperatur ermittelte Absolutfeuchte und ϑ₂ eine aus der angenommenen Außenluftrelativfeuchte ermittelte zweite Temperaturgröße ist, wobei der Abluftmassenstrom und/oder der Außenluftmassenstrom erhöht werden/wird, wenn die Abluftrelativfeuchte einen Abluftrelativfeuchtegrenzwert übersteigt und die Außenlufttemperatur kleiner als der Außenlufttemperaturgrenzwert ist.According to the invention, this is achieved with a method having the features of claim 1. It is provided that from the exhaust air relative humidity, the exhaust air temperature and a constant and manually predeterminable assumed outdoor air relative humidity using the equation $${\mathrm{\vartheta }}_{\mathrm{AU},\mathrm{Max}}={\mathrm{\vartheta }}_1\ln \left({\mathrm{x}}_{\mathrm{FROM}}\right)-{\mathrm{<figure-callout\; id="2"\; label="\theta "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\vartheta </figure-callout>}}_2$$

an outside air temperature limit value is determined, where ϑ _{1 is} a first temperature variable, x _{AB is} an absolute humidity determined from the exhaust air relative humidity and the extract air temperature and ϑ _{2 is} a second temperature variable determined from the assumed outside air relative humidity, whereby the exhaust air mass flow and / or the outside air mass flow are / is increased if the exhaust air relative humidity exceeds an exhaust air relative humidity limit value and the outside air temperature is lower than the outside air temperature limit value.

To carry out the process, the relative humidity of the exhaust air and the temperature of the exhaust air are measured. In addition, the outside air temperature of the outside air is determined, in particular measured. The exhaust air relative humidity corresponds to the relative humidity of the exhaust air taken from the room or the relative humidity Humidity of the room air present in the room. The exhaust air temperature is analogously the temperature of the exhaust air taken from the room or the temperature of the room air present in the room.

The outside air relative humidity is determined or estimated within the scope of the method according to the invention. For example, the relative humidity of the outside air can be set on the ventilation device, in particular ex works or by a user of the ventilation device. In this respect, the outdoor air relative humidity is a constant value that can be specified manually. Alternatively, the relative humidity of the outside air can of course be estimated or measured. The exhaust air relative humidity, the exhaust air temperature and the outside air relative humidity are now summarized in the form of the outside air temperature limit value. To this extent, the outside air temperature limit value is a function of the relative humidity of the exhaust air, the temperature of the exhaust air and the relative humidity of the outside air.

In the case of high relative humidity in the room and low outside temperatures, condensation can form in cold areas, especially on cold outside walls of the room. Furthermore, too high relative humidity in the room is perceived as stuffy. One aim of the method according to the invention is to reduce the relative humidity of the room air or the relative humidity of the exhaust air, or at least limit it upwards.

If the exhaust air relative humidity exceeds the exhaust air relative humidity limit value, then it is desirable to increase the exhaust air mass flow and / or the outside air mass flow in order to remove moist air from the room and / or to supply dry air to the room. Correspondingly, by increasing the exhaust air mass flow and / or the outside air mass flow, the relative humidity and therefore the relative humidity of the air can only be reduced if the absolute humidity of the outside air is less than the absolute humidity of the extract air.

This results in two conditions that must be met so that the exhaust air mass flow and / or the outside air mass flow are increased. On the one hand, the exhaust air relative humidity must exceed the exhaust air relative humidity limit value, i.e. be greater than this. On the other hand, the outside air temperature must be lower than the outside air temperature limit value, which was determined from the extract air relative humidity, the extract air temperature and the outside air relative humidity. The exhaust air relative humidity limit value is preferably adjustable on the ventilation device, in particular ex works and / or by the user of the ventilation device.

The increase in the exhaust air mass flow and / or the outside air mass flow occurs, for example, as follows: First, a default exhaust air mass flow and / or default outside air mass flow is determined, which is set, for example, by the user on the ventilation device. The default exhaust air mass flow and / or the default external air mass flow can, however, also result in the course of an automatic operation of the ventilation device, whereby they are determined as a function of at least one parameter.

Starting from this default exhaust air mass flow and / or default outside air mass flow, the increase in the exhaust air mass flow and / or the outside air mass flow takes place so that the Exhaust air mass flow actually set on the ventilation device is greater than the default exhaust air mass flow and / or the set outside air mass flow is greater than the default outside air mass flow.

According to the above statements, it can be provided that the exhaust air relative humidity is determined by means of at least one humidity sensor. The humidity sensor can either be provided in the ventilation device, in particular in an exhaust air flow from the ventilation device, or alternatively in the room, at a distance from the ventilation device. As already explained above, the relative humidity of the exhaust air essentially corresponds to the relative humidity of the room air.

In a preferred embodiment of the invention it can be provided that, when using several humidity sensors, the relative humidity of the exhaust air is set equal to the largest humidity reading of the humidity sensors. To this extent, not only a single humidity sensor is provided, although this can of course be the case. The multiple humidity sensors are arranged as desired, for example at least one of the humidity sensors or, alternatively, multiple humidity sensors are located in the ventilation device, in particular in the exhaust air flow. Additionally or alternatively, at least one further humidity sensor, in particular a plurality of further humidity sensors, can be arranged in the room, in particular at a distance from the ventilation device.

Each of these humidity sensors now supplies a measured humidity value which indicates the relative humidity of the exhaust air or the relative humidity of the room air at the location of the respective humidity sensor.

The relative humidity of the exhaust air, from which the outside air temperature limit value is determined, now corresponds to the largest humidity reading of the humidity sensors.

In normal operation of the ventilation device, it can be provided that the exhaust air mass flow corresponds to the outside air mass flow, that is to say as much air is extracted from the room by means of the ventilation device as is supplied to it. However, this does not have to be the case. In at least one operating mode of the ventilation device, the exhaust air mass flow can be different from the outside air mass flow, that is to say either larger or smaller than it. Accordingly, more exhaust air is extracted from the room than is supplied to it, or vice versa. In the extreme case it can be provided that the exhaust air mass flow or the outside air mass flow is set to zero, i.e. in the former case only supply air is supplied to the room and in the latter case only exhaust air is extracted from the room.

An outside air mass flow that differs from the exhaust air mass flow is set in particular when at least one open room closure element and / or building closure element is detected. The room locking element or building locking element is, for example, a door, a window or the like. In its open state, the room closure element or building closure element preferably provides a flow connection from the room to the external environment, so that either air can escape from the room into the external environment or can enter the room from the external environment.

ermittelt wird, wobei ϑ₁ eine erste Temperaturgröße, x_AB eine Absolutfeuchte und ϑ₂ eine aus der angenommenen Außenluftrelativfeuchte ermittelte zweite Temperaturgröße ist.The invention provides that the outside air temperature _limit value ϑ _{AU, max} using the equation $${\mathrm{\vartheta }}_{\mathrm{AU},\mathrm{Max}}={\mathrm{\vartheta }}_1\ln \left({\mathrm{x}}_{\mathrm{FROM}}\right)-{\mathrm{<figure-callout\; id="2"\; label="\theta "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\vartheta </figure-callout>}}_2$$

is determined, where ϑ _{1 is} a first temperature variable, x _{AB is} an absolute humidity and ϑ _{2 is} a second temperature variable determined from the assumed outdoor air relative humidity.

The first temperature variable ϑ ₁ is a constant value which is set in particular invariably on the ventilation device, for example ex works. In this case, the first temperature variable cannot be changed or set by a user of the ventilation device. Of course, this can also be provided in an alternative embodiment. The first temperature variable is given, for example, in the unit ° C and has a value from 10 ° C to 20 ° C, preferably 12 ° C to 16 ° C, preferably 14 ° C to 15 ° C or 14 ° C to 14.5 ° C on. For example, the first temperature variable has the value 14 ° C, 14.1 ° C, 14.2 ° C, 14.3 ° C, 14.4 ° C or 14.5 ° C.

The absolute humidity x _AB corresponds, for example, to the absolute humidity of the exhaust air, so to that extent an exhaust air absolute humidity. The second temperature variable is determined from the relative humidity of the outside air, in this respect from a function of the relative humidity of the outside air. For example, the second temperature variable is determined using a mathematical relationship, a characteristic diagram and / or a table from the outside air relative humidity.

The second temperature variable ϑ ₂ is preferably given in the unit ° C. For example, it has a relative humidity outside the room of 60% a value between 10 ° C and 11 ° C, in particular between 10.5 ° C and 11 ° C. With a relative humidity of the outside air of 70%, the second temperature variable has a value from 12 ° C to 14 ° C, in particular from 12.5 ° C to 13.5 ° C. If the relative humidity of the outside air is 80%, the second temperature variable can have a value between 14 ° C and 15 ° C, in particular a value between 14.5 ° C and 15 ° C.

angegeben werden. Auch eine Normalisierung der Absolutfeuchte auf eine einheitenlose Größe kann vorgesehen sein.In order to ensure that the outside air temperature limit value can be determined on the basis of the equation, provision can also be made to limit the absolute humidity downwards to a value of zero. In this case the equation can be written as $${\mathrm{\vartheta }}_{\mathrm{AU},\mathrm{Max}}={\mathrm{\vartheta }}_1\ln \left(\mathrm{Max}\left(0,{\mathrm{x}}_{\mathrm{FROM}}\right)\right)-{\mathrm{<figure-callout\; id="2"\; label="\theta "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\vartheta </figure-callout>}}_2$$

can be specified. A normalization of the absolute humidity to a unitless size can also be provided.

A preferred embodiment of the invention provides that a constant value is used as the first temperature variable. This has already been pointed out above. The first temperature variable is stored permanently or unchangeably in the ventilation device and cannot be changed by the user of the ventilation device.

ermittelt wird, wobei x_max eine Maximalfeuchte und ρ_AB die Abluftrelativfeuchte ist. Die in der vorstehend angegebenen Gleichung verwendete Absolutfeuchte liegt insoweit als Funktion aus der Maximalfeuchte und der Abluftrelativfeuchte vor. Die Maximalfeuchte gibt dabei die maximale absolute Feuchtigkeit an und kann insoweit auch als Maximalabsolutfeuchte bezeichnet werden.Another embodiment of the invention provides that the absolute humidity based on the relationship $${\mathrm{x}}_{\mathrm{FROM}}={\mathrm{x}}_{\mathrm{Max}}{\mathrm{\rho }}_{\mathrm{FROM}}$$

is determined, where x _{max is} a maximum humidity and ρ _{AB is} the relative humidity of the exhaust air. The absolute humidity used in the equation given above is available as a function of the maximum humidity and the relative humidity of the exhaust air. The maximum humidity indicates the maximum absolute humidity and can in this respect also be referred to as the maximum absolute humidity.

(mit x=0..m)
oder anders ausgedrückt $$x_{\max }={\displaystyle \sum _{x=0}^m{a}_x{\vartheta }_{\mathit{AB}}^x}$$

verwendet wird. Die Beziehung zur Ermittlung der Maximalfeuchte kann insoweit beliebiger Ordnung, in den zuletzt angegeben Gleichungen als m bezeichnet, sein. Beispielsweise wird eine Beziehung erster Ordnung, zweiter Ordnung oder dritter Ordnung verwendet, wobei in letzterem Fall die Beziehung als $${\mathrm{x}}_{\max }={\mathrm{a}}_3{{\mathrm{\vartheta }}^3}_{\mathrm{AB}}+{\mathrm{a}}_2{{\mathrm{\vartheta }}^2}_{\mathrm{AB}}+{\mathrm{a}}_1{\mathrm{\vartheta }}_{\mathrm{AB}}+{\mathrm{a}}_0$$

angegeben werden kann.A preferred embodiment of the invention provides that the maximum humidity is determined from the exhaust air temperature, with the relationship $${\mathrm{x}}_{\mathrm{Max}}={\displaystyle \sum {\mathrm{a}}_{\mathrm{x}}{{\mathrm{\vartheta }}^{\mathrm{x}}}_{\mathrm{FROM}}}$$

(with x = 0..m)
or in other words $$x_{\mathrm{Max}}={\displaystyle \sum _{x=0}^m{a}_x{\vartheta }_{\mathit{FROM}}^x}$$

is used. The relationship for determining the maximum moisture can be of any order, referred to as m in the last equations given. For example, a first-order, second-order, or third-order relationship is used, in the latter case the relationship as $${\mathrm{x}}_{\mathrm{Max}}={\mathrm{a}}_3{{\mathrm{\vartheta }}^3}_{\mathrm{FROM}}+{\mathrm{a}}_2{{\mathrm{<figure-callout\; id="2"\; label="\theta "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\vartheta </figure-callout>}}^2}_{\mathrm{FROM}}+{\mathrm{a}}_1{\mathrm{\vartheta }}_{\mathrm{FROM}}+{\mathrm{a}}_0$$

can be specified.

• a₃ = 0,000212680975552423,
• a₂ = 0,0095118829163135,
• a₁ = 0,260953396021405, und
• a₀ = 3,71104339859367.

The coefficients are preferably selected in such a way that the relationship reproduces the saturation amount of water vapor in the air as precisely as possible, in particular in an operating temperature range the ventilation system, which extends in particular from - 20 ° C to +40 ° C. For example, the coefficients have the following values:

• a ₃ = 0.000212680975552423,
• a ₂ = 0.0095118829163135,
• a ₁ = 0.260953396021405, and
• a ₀ = 3.71104339859367.

A further development of the invention provides that the second temperature variable is determined from the assumed relative humidity of the outside air by means of a mathematical relationship, a characteristic field and / or a table. This has already been pointed out above. In the latter case, for example, the second temperature variable is specified for several different values of the relative humidity of the outside air. For example, the second temperature variable for which the outside air relative humidity assigned in the table is closest to the assumed outside air relative humidity is read from the table. Alternatively, the second temperature variable can also be determined by interpolation or extrapolation from the table, for example by linear interpolation.

In a further preferred embodiment of the invention it is provided that the exhaust air mass flow and / or the outside air mass flow are / is only increased when the outside air temperature is lower than the outside air temperature limit by an activation temperature difference. With such a configuration, it is not sufficient if the outside air temperature is lower than the outside air temperature limit value. Rather, it must be between the outside air temperature and the outside air temperature limit value is at least the activation temperature difference.

If the outside air temperature corresponds at least essentially to the outside air temperature limit value, it can be assumed that the air present in the outside environment has a similar absolute humidity to the exhaust air or room air. Correspondingly, increasing the exhaust air mass flow or the outside air mass flow cannot reduce the humidity in the room. However, if the outside air temperature is at least the activation temperature difference lower than the outside air temperature limit value, it can be assumed that the outside air is drier than the exhaust air or room air.

In a further embodiment of the invention it is provided that the exhaust air mass flow and / or the outside air mass flow are / is reduced again when the exhaust air relative humidity falls below an exhaust air relative humidity limit value by a certain deactivation humidity difference. As already mentioned at the beginning, the aim of the method is to reduce the humidity in the room. Correspondingly, the exhaust air mass flow or the outside air mass flow are increased if the exhaust air relative humidity exceeds the exhaust air relative humidity limit value and the outside air temperature is also lower than the outside air temperature limit value.

If the air humidity in the room or the relative humidity of the exhaust air can be sufficiently reduced by this increase, the exhaust air mass flow and / or the outside air mass flow can be reduced again, in particular to their respective levels Baseline they were on before they increased. For example, in this case the exhaust air mass flow corresponds to the aforementioned default exhaust air mass flow and the outside air mass flow corresponds to the default outside air mass flow. To ensure that the air humidity in the room has actually been reduced, the deactivation humidity difference is specified, which is different from zero, in particular at least 2 percentage points, at least 4 percentage points, at least 6 percentage points, at least 8 percentage points or at least 10 percentage points.

Furthermore, in a preferred embodiment of the invention it can be provided that the outside air temperature limit value is determined periodically, the exhaust air mass flow and / or the outside air mass flow being reduced again when the outside air temperature is greater than or equal to the outside air temperature limit value. While the ventilation device is operated with the increased exhaust air mass flow and / or outside air mass flow, the conditions in the outside environment can change. This should be responded to adequately by periodically redetermining the outside air temperature limit value and the outside air temperature.

The exhaust air mass flow or the outside air mass flow should be reduced again, in particular to the default exhaust air mass flow or the default outside air mass flow, if the humidity in the room can no longer be reduced by the increased exhaust air mass flow or outside air mass flow, because the humidity in the outside environment, now changed at least similar to that there is humidity in the room.

A further development of the invention provides that the exhaust air mass flow and / or the outside air mass flow are only increased when a winter operating mode is set on the ventilation device. In this respect, several different operating modes can be set on the ventilation device, for example a summer operating mode and the winter operating mode. The setting can preferably be made by the user of the ventilation device. Suitable input means are provided for this purpose, for example. The air humidity present in the room or the relative humidity of the exhaust air can take place particularly efficiently with cold and therefore dry outside air. This is particularly the case in winter. In summer, on the other hand, the outside air is usually more humid due to the higher temperature, so that reducing the humidity in the room cannot be carried out as efficiently as in winter.

It can additionally or alternatively be provided that a switchover is made between a summer operating mode and the winter operating mode as a function of a current season. The current time of year is determined, for example, by means of a clock in the ventilation device or is specified by a central point.

In a further preferred embodiment of the invention it is provided that a target exhaust air mass flow and / or a target external air mass flow are / is determined from the exhaust air relative humidity and the exhaust air mass flow is / is set to the target exhaust air mass flow and / or the external air mass flow is / is set to the target external air mass flow. In this respect, it is not only determined from the relative humidity of the exhaust air or the relative humidity of the room whether the exhaust air mass flow and / or the outside air mass flow is increased should be. Rather, the relative humidity of the exhaust air finds its way directly into the target exhaust air mass flow or the target outside air mass flow.

The target exhaust air mass flow or the target outside air mass flow is therefore available as a function of the exhaust air relative humidity. For example, it is provided that at a first value of the relative humidity of the exhaust air, the target exhaust air mass flow rate is set to a first target exhaust air mass flow rate and / or the target external air mass flow rate is set to a first target external air mass flow rate. If, on the other hand, the relative humidity of the exhaust air has a second value which is greater than the first value, then the target exhaust air mass flow should be set to a second target exhaust air mass flow and / or the target external air mass flow should be set to a second target external air mass flow, the second target exhaust air mass flow being greater than the first target exhaust air mass flow or the second Setpoint outside air mass flow is greater than the first setpoint outside air mass flow.

Particularly preferably, a fixed relationship is defined between values of the relative humidity of the exhaust air on the one hand and the target exhaust air mass flow rate and / or the target outside air mass flow rate on the other hand. For example, a linear relationship is provided here. Alternatively, relationships of higher or lower order can of course also be used.

If a default exhaust air mass flow and / or a default outside air mass flow are determined, for example, the larger value is selected from the default outside air mass flow and the set outside air mass flow and the outside air mass flow is applied to the ventilation device this set. Additionally or alternatively, the default exhaust air mass flow rate and the target exhaust air mass flow rate can be used.

A further advantageous embodiment of the invention provides that the target exhaust air mass flow and / or the target outside air mass flow are selected to be higher, the higher the relative humidity of the exhaust air. This has already been discussed above. The determination of the target exhaust air mass flow and / or the target external air mass flow can be determined by means of a mathematical relationship, a characteristic field and / or a table, in particular from the exhaust air relative humidity.

A further development of the invention provides that the exhaust air and / or supply air are passed through a heat exchanger or heat exchanger for temperature control. The heat exchanger is provided to extract heat from the exhaust air and / or to supply heat to the supply air. Particularly preferably, both the exhaust air and the supply air are passed through the heat exchanger, so that the heat extracted from the exhaust air can be used for tempering, in particular heating, the supply air. Of course, provision can also be made for only part of the exhaust air and / or only part of the supply air to be passed through the heat exchanger, but this is preferably the case for all of the exhaust air or all of the supply air.

In a further embodiment of the invention it is provided that an enthalpy exchanger is used as the heat exchanger. While the heat exchanger can of course be designed as a sensible heat exchanger, it is particularly advantageous if it is available as an enthalpy exchanger. The enthalpy exchanger, like the sensitive heat exchanger, has means for transferring heat, in particular from the exhaust air to the supply air. In addition, however, the enthalpy exchanger has means by means of which moisture can be exchanged, in particular transferred from the exhaust air to the supply air.

For this purpose, a film or membrane through which water vapor can diffuse, for example due to osmosis, is provided in the enthalpy exchanger, for example for fluidic separation of the supply air from the exhaust air. The film or membrane consists for example of a polymer.

In a further embodiment of the invention it is provided that the exhaust air mass flow and / or the outside air mass flow are increased during an intensive ventilation mode. The ventilation device is therefore normally operated, for example, in a normal operating mode. As soon as it is determined that the exhaust air relative humidity exceeds the exhaust air relative humidity limit value and the outside air temperature is lower than the outside air temperature limit value, a switch is made to the intensive ventilation mode, in particular from the normal mode.

In the intensive ventilation operating mode, the exhaust air mass flow and / or the outside air mass flow are increased, for example the increase occurs with or shortly after switching to the intensive ventilation operating mode. After the increase, it can be provided that the increased exhaust air mass flow and / or the increased outside air mass flow during the further course of the intensive ventilation operating mode remain constant until the intensive ventilation mode is ended.

In a preferred embodiment of the invention it is provided that the exhaust air relative humidity is temporarily stored as an initial value at the beginning of the intensive ventilation operating mode. Immediately when switching to the intensive ventilation mode, the output value of the relative humidity of the exhaust air is set equal to and saved. The output value remains saved for the entire duration of the intensive ventilation mode and is therefore constant.

A preferred embodiment of the invention provides that, during the intensive ventilation mode, the currently present exhaust air relative humidity is compared with a comparison value determined from the initial value, a bypass around the heat exchanger being at least partially opened if the exhaust air relative humidity is greater than or equal to the comparison value. For example, the comparison value corresponds to the initial value. Alternatively, the comparison value can also be selected to be smaller than the output value, for example by a certain offset.

The comparison between the relative humidity of the exhaust air and the reference value is made either continuously or at defined time intervals. If, in the context of the comparison, it is found that the relative humidity of the exhaust air is greater than or equal to the comparison value, i.e. that the humidity in the room is greater than the humidity present at the start of the intensive ventilation mode, the bypass is opened at least partially, in particular completely.

The bypass preferably serves to guide the outside air or supply air at least partially, in particular completely, around the heat exchanger. Such a procedure is particularly useful if the heat exchanger is designed as an enthalpy exchanger. As already explained above, in addition to heat, moisture can also be transferred in the enthalpy exchanger. However, this can be undesirable if the humidity in the room is too high or should be reduced. In particular, it makes sense to open the bypass when the humidity in the outside environment is greater than or equal to the humidity in the room.

Another embodiment of the invention provides that when the bypass is at least partially open, the supply air supplied to the room is heated by means of a heating device. If the supply air is routed through the bypass and the heat exchanger, it cannot be heated in this. It is therefore necessary to adjust the temperature of the supply air accordingly. The heating device is provided for this purpose. For example, with the aid of the heating device, the supply air is set to a certain temperature, in particular a default temperature which is predetermined by the user of the ventilation device, in particular set in a controlling and / or regulating manner.

In a further preferred embodiment of the invention it is provided that the room has several ventilation zones from which exhaust air with a certain proportion of the exhaust air mass flow is taken and / or supply air with a certain proportion of the outside air mass flow is supplied. The room is divided into several ventilation zones. Each of the ventilation zones is separate Exhaust air can be taken from other ventilation zones and / or supply air can be supplied. The exhaust air taken from all ventilation zones together has the exhaust air mass flow, while the supply air supplied to all ventilation zones has the outside air mass flow. Of course, it can be provided that the number of ventilation zones from which exhaust air is taken is different from or corresponds to the number of ventilation zones into which supply air is supplied. For example, the number of ventilation zones from which exhaust air is extracted is greater or smaller than the number of those ventilation zones into which supply air is supplied. A reverse configuration can also be provided.

Another embodiment of the invention provides that humidity is determined in each of the ventilation zones and the proportion of the exhaust air mass flow and / or the proportion of the outside air mass flow are / is increased for the ventilation zone in which the higher humidity is present. It is therefore not only intended to increase the exhaust air mass flow and / or the outside air mass flow globally. Rather, the exhaust air mass flow or the outside air mass flow is specifically distributed locally to the ventilation zones. In this way, the air between the ventilation zones can be homogenized.

It should be noted here that the ventilation zones do not have to be arranged directly connected in terms of fluid technology. For example, the ventilation zones can be in different rooms of a building, which in their entirety describe the room to which the ventilation device is assigned.

As an alternative, the multiple ventilation zones can of course also be present in a single room, which can accordingly be viewed as the room having the ventilation device.

The invention also relates to a ventilation device having the features of claim 8.

The invention naturally also relates to a room which has a ventilation device according to the above statements. For example, the space can be a room in a building or the building itself.

Figur

ein Ablaufdiagramm eines Verfahrens zum Betreiben einer Lüftungseinrichtung für einen Raum.

The invention is explained in more detail below with reference to the exemplary embodiments shown in the drawing, without restricting the invention. It shows the only one

figure

a flow chart of a method for operating a ventilation device for a room.

The figure shows a flow diagram in which a method for operating a ventilation device for a room is shown. The ventilation device is designed to take exhaust air with a specific exhaust air mass flow from the room during a ventilation process by means of the ventilation device and / to take outside air with a specific outside air mass flow from the outside environment and supply it to the room in the form of supply air.

First, in a first step 1, an exhaust air relative humidity limit value is set, for example by a user of the ventilation device. In a step 2 the exhaust air relative humidity is the Exhaust air measured. In a comparison 3, the measured relative exhaust air humidity is then compared with the set exhaust air relative humidity limit value. If it is smaller, the method is ended in step 4.

If, on the other hand, the exhaust air relative humidity is greater than the exhaust air relative humidity limit value, an outside air temperature limit value is determined from an exhaust air temperature measured in a step 5 in a step 6. This describes the temperature in the outside environment at which the air humidity in the outside environment corresponds at most to the air humidity in the room, in particular is lower than this.

In a step 7, an outside air temperature is now measured. This is compared in a step 8 with the outside air temperature limit value. If it is determined that the outside air temperature is greater than or equal to the outside air temperature limit value, the method is ended in a step 9. Otherwise, a step 10 is initiated. In this context, the exhaust air mass flow and / or the outside air mass flow are increased in order to remove more air from the room and / or to supply more air to it. In this way, the humidity in the room can be reduced.

Claims (8)

1. A method for operating a ventilation device for an area, wherein exhaust air is removed from the area during a ventilation process by means of the ventilation device at a certain exhaust air mass flow rate, and/or ambient air is removed from the outside environment at a certain ambient air mass flow rate and is supplied to the area in the form of supply air, wherein an exhaust air relative humidity and an exhaust air temperature of the exhaust air as well as an ambient air temperature of the ambient air are measured, characterised in that an ambient air temperature threshold value is determined from the exhaust air relative humidity, the exhaust air temperature, as well as a constant and manually predeterminable assumed ambient air relative humidity by means of the equation $${\mathrm{\vartheta }}_{\mathrm{AU},\max }={\mathrm{\vartheta }}_1\ln \left({\mathrm{x}}_{\mathrm{AB}}\right)-{\mathrm{\vartheta }}_2$$

   

   wherein ϑ₁ is a constant first temperature variable, x_AB is an absolute humidity of the exhaust air determined from the exhaust air relative humidity and the exhaust air temperature, and ϑ₂ is a second temperature variable determined from the assumed ambient air relative humidity, wherein the exhaust air mass flow rate and/or the ambient air mass flow rate are/is increased when the exhaust air relative humidity exceeds an exhaust air relative humidity threshold value and the ambient air temperature is smaller than the ambient air temperature threshold value.
2. The method according to any one of the preceding claims, characterised in that the absolute humidity is determined by means of the relationship $${\mathrm{x}}_{\mathrm{AB}}={\mathrm{x}}_{\max }{\mathrm{\rho }}_{\mathrm{AB}},$$

   

   wherein x_max is a maximal humidity and ρ_AB is the exhaust air relative humidity.
3. The method according to any one of the preceding claims, characterised in that the maximal humidity is determined from the exhaust air temperature, whereby the relationship $${\mathrm{x}}_{\max }={\displaystyle \sum {\mathrm{a}}_{\mathrm{x}}{{\mathrm{\vartheta }}^{\mathrm{x}}}_{\mathrm{AB}}}$$

   

   is used.
4. The method according to any one of the preceding claims, characterised in that the second temperature variable is determined from the assumed ambient air relative humidity by means of a mathematical relationship, a characteristic diagram, and/or a table.
5. The method according to any one of the preceding claims, characterised in that the exhaust air mass flow rate and/or the ambient air mass flow rate are/is only increased when the ambient air temperature is smaller by an activation temperature difference than the ambient air temperature threshold value.
6. The method according to any one of the preceding claims, characterised in that the exhaust air mass flow rate and/or the ambient air mass flow rate are/is reduced again when the ambient air relative humidity falls by a specified difference below an exhaust air relative humidity threshold value.
7. The method according to any one of the preceding claims, characterised in that the ambient air temperature threshold value is determined periodically, wherein the exhaust air heat flow rate and/or the ambient air mass flow rate are/is reduced again when the ambient air temperature is greater than or equal to the ambient air temperature threshold value.
8. A ventilation device for an area, in particular for carrying out the method according to any one or several of the preceding claims, wherein the ventilation device is configured to remove exhaust air during a ventilation process from the area at a certain exhaust air mass flow rate and/or to remove ambient air from the outside environment at a certain ambient air mass flow rate and to supply it to the area in the form of supply air, wherein an exhaust air relative humidity and an exhaust air temperature of the exhaust air as well as an ambient air temperature of the ambient air are measured, characterised in that the ventilation device is configured to determine an ambient air temperature threshold value from the exhaust air relative humidity, the exhaust air temperature, as well as a constant and manually predeterminable assumed ambient air relative humidity by means of the equation $${\mathrm{\vartheta }}_{\mathrm{AU},\max }={\mathrm{\vartheta }}_1\ln \left({\mathrm{x}}_{\mathrm{AB}}\right)-{\mathrm{\vartheta }}_2$$

   

   wherein ϑ₁ is a constant first temperature variable, x_AB is an absolute humidity of the exhaust air determined from the exhaust air relative humidity and the exhaust air temperature, and ϑ₂ is a second temperature variable determined from the assumed ambient air relative humidity, wherein the exhaust air mass flow rate and/or the ambient air mass flow rate are/is increased when the exhaust air relative humidity exceeds an exhaust air threshold value and the ambient air temperature is smaller than the ambient air temperature threshold value.

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