Method of ventilation and ventilation device

Abstract

Heating and air conditioning systems influence temperature and humidity in buildings and vehicles. They are known for consuming a considerable amount of energy. Pure ventilation systems, such as those often found in kitchens or bathrooms, require less energy but have an uncontrolled impact on the climate. The present invention aims to extract the physically possible maximum energy efficiency from room climate control systems. In particular, it focuses on controlling relative humidity to prevent or minimize corrosion, mold, and algae growth. Within an adjustable climate zone for permissible temperature and humidity, ventilation is used to try to achieve the warm, dry optimum. Preferably, the control system uses indoor and outdoor sensors to measure temperature and humidity.This means that the specific humidity may be increased if this results in a long-term decrease in relative humidity or if the relative humidity remains below the limit. The invention works best with a heat exchanger that can be bypassed in favorable weather conditions to heat the building or vehicle volume.

Description

[0001] The present invention relates to a ventilation method according to the preamble of claim 1 and to a ventilation device for carrying out the method.

[0002] Excessive humidity is a common cause of various problems, especially indoors such as basements and storage rooms, retail spaces, but also in vehicles: Molds These are microorganisms that grow at a certain relative humidity, which is below saturation. They are aesthetically unappealing and can be hazardous to health. Their volatile metabolic products are known as... musty smell perceived.

[0003] rust Rust also forms more quickly the higher the relative humidity, with a disproportionately strong correlation. Below approximately 65% ​​humidity, hardly any rust forms, regardless of temperature, without the presence of pollutants.

[0004] Salt efflorescenceThese problems occur when moisture dissolves salts in the masonry, the solution migrates to the surface, and the water evaporates there. The remaining salts expand as they crystallize, thus destroying the masonry.

[0005] clumping This occurs in stored goods such as sugar, salt or soap when the humidity is too high.

[0006] fogged-up window panes They obstruct the view to the outside, which is a particular problem in vehicles.

[0007] There are various methods for controlling humidity; the standard DIN 1946-6 provides a good overview: heating systems Heating only lowers relative humidity by increasing the temperature. Air pollutants are not removed; no water is extracted from the building volume. Heating is considered the least energy-efficient solution for lowering relative humidity. Patent application EP3961117A describes a heating system for the purpose of humidity control.

[0008] DehumidifierThey lower both specific humidity and relative humidity, but they consume a lot of electricity, are noisy, and because they operate in recirculation mode, they do not supply fresh air; air pollutants are not removed.

[0009] Ventilation systems without heat exchangers They supply fresh air to the room, while airborne pollutants are extracted or displaced. They are indifferent to humidity, humidifying or dehumidifying depending on the current state of the outside air. Air exchange can be natural, as with free ventilation (e.g., window ventilation), or mechanical, as with fan-assisted ventilation (e.g., classic bathroom fans).

[0010] Ventilation systems with a pure heat exchanger Fresh air is supplied to the room, and heat is transferred simultaneously. In winter, the incoming air is heated by the warm exhaust air, while in summer it is cooled by the cooler exhaust air. The specific humidity and humidity level remain constant.

[0011] The better ventilation systems with a pure heat exchanger have a bypass damper that allows the heat exchanger to be bypassed. With the bypass activated, the effect on temperature and humidity is the same as with natural ventilation. However, in state-of-the-art systems, the bypass damper is only used to cool the rooms at night during the summer. Therefore, it is usually called a summer bypass.

[0012] Ventilation systems with enthalpy heat exchangersFresh air is supplied to the room, and heat and moisture are transferred simultaneously. Mass (water) is also transferred from the exhaust air to the supply air, or vice versa, via suitable exchange walls. This results in changes to specific humidity, humidity level, relative humidity, and temperature. In the height of summer, and in an interior with few sources of moisture, this method allows for ventilation, transferring some of the moisture from the outside air directly back into the exhaust air. In winter, moisture loss can be limited, thus recovering energy and preventing the room from becoming too dry. Enthalpy heat exchangers with vapor-permeable plates offer a constant recovery rate. Rotary heat exchangers and oscillating fans can vary their recovery rate depending on their rotational speed or cycle time; depending on their function, they are either pure heat exchangers or enthalpy heat exchangers.

[0013] Dew point controlsIn conjunction with fans, window, door, or gate drives, these systems calculate the dew point, or the specific or absolute humidity, from the relative humidity and the temperature (measured both inside and outside). They only ventilate when it is drier outside than inside (see, for example, EP2947396A, EP3098527A). The major disadvantages of dew point controls are that they cool rooms down and cannot be used for ventilation for a significant portion of the time.

[0014] Monoblocks They combine a dehumidifier, a heating element, and a heat exchanger with dampers and fans. They can fully control the climate, but without proper control according to this invention, energy consumption is significantly higher than with simple ventilation systems. The devices are large and expensive.

[0015] Solar warm air collectorsThese systems warm outside air and blow it into a building during the day (e.g., EP1448937A). However, especially in summer, the most critical time in terms of humidity, they would overheat the room and blow in very humid air, which is why better models shut down during this period. But this means there is neither ventilation nor dehumidification. Without proper control, there is a risk that the incoming air will create a climate conducive to mold growth on cooler walls.

[0016] Split air conditioners Similar to monoblocks, they can completely control the climate, but they do not ventilate and they reach physical limits when dehumidifying unheated or only partially heated rooms.

[0017] Ventilation systems, particularly for monoblocks, that operate with a climate zone instead of a fixed point already exist. Application WO2012 / 049897A1 describes how the individual registers are switched and operated in such a system when the outside air humidity is suitable. In this application, the climate zone is defined by humidity and temperature. Application US 2011 / 0306288AI defines a target climate for a server room with a monoblock based on absolute and relative humidity, enthalpy, and temperature. The climate is divided into zones, and efforts are made to minimize energy consumption.

[0018] One object of the present invention is to reduce the energy required to maintain a given indoor climate.

[0019] A method that solves this problem is specified in claim 1. The further claims specify preferred embodiments of the method as well as devices for carrying out the method.

[0020] In the following description and claims, "approximately" is to be understood as a tolerance around the specified value that is customary in the industry. In particular, such a tolerance can be considered to be a deviation of 0.1 °C for temperature specifications and a deviation of 1% for humidity specifications in percent.

[0021] An energy-efficient solution to the problem is based on the understanding that one usually ventilates first before using a heat pump or heating system. Furthermore, while parameters such as absolute or specific humidity or dew point can be measured or calculated for intelligent control, ultimately the... relative Moisture is relevant for controlling both mold and algae growth as well as rust formation.

[0022] The invention results in the transfer of heat into building components such as walls, floors, and the ground beneath the building on warm days. This heat helps to keep the relative humidity low at night and on cold days. The same behavior is observed throughout the cold and warm seasons. The ground can store heat for months.

[0023] According to a preferred aspect of the invention, an (indirect) measurement of the surface moisture is also carried out at the coldest point of the building volume.

[0024] The procedure step by step: 1. A target climate zone is defined for the building volume, in the simplest case with four values ​​for minimum and maximum relative temperature and humidity ( T min , T max , φ min , φ max in Fig. 1 ). It simply needs to be an area in the T- φ -Diagram (grey area in Fig. 1) can be set up, this can also be done with additional pairs of values ​​for wet-bulb temperature, specific humidity, or enthalpy. The value for maximum humidity is of particular importance; it depends on the objective, e.g., approximately 65% ​​to prevent rust. 2. The relative humidity and temperature of the room and supply air are determined or measured. As long as the ventilation system is running, a humidity and temperature sensor in the exhaust air duct provides the state of the mixed room air. The sensor pair 8 in Fig. 2 It can be moved arbitrarily in the direction of airflow up to the heat exchanger. If, however, the system is to be able to be switched off, at least one humidity and temperature sensor is required in the room. As long as the ventilation system is running, a humidity and temperature sensor in the supply air duct (5 in Fig. 2) the required values ​​to determine the direction in which ventilation changes the climate. If, however, the system is to be able to be switched off, an external sensor for humidity and temperature is needed (1 in Fig. 2Using the values ​​from the outdoor sensor and known heat exchanger recovery values, the supply air climate can be estimated if the ventilation system were operating. Further values ​​such as saturation vapor pressure, humidity level, and specific humidity can be calculated from the relative humidity and temperature. The outdoor sensor is preferably located in a small climate-controlled enclosure to protect it from overheating in sunlight. The indoor sensor is preferably located where it is protected from mechanical damage and where the relative humidity is within the preferred operating range. In smaller systems with only one exhaust air opening, it is preferably mounted near the opening. 3. The direction in which the climate is changed is calculated individually for each of the available ventilation methods (bypass, heat exchanger, or enthalpy heat exchanger). These change vectors have a first component for temperature and a second for relative humidity.The change in a quantity such as temperature or humidity, which serve as components of a direction vector, is understood as the change per unit of time achieved by a ventilation method. In practice, ventilation methods are usually equally or approximately equally effective, so that instead of the change per unit of time, the achievable change suffices, i.e., the difference between the current state and the state that can be achieved with the ventilation method alone after any arbitrarily long time. 4. A diagram is created (. Fig. 1 ) with relative humidity on the abscissa and temperature on the ordinate. It is important that the abscissa is related to the ordinate by the factor defined in Eqs. 1.12 and 1.16. cs The diagram is scaled. In this diagram, the point representing the indoor climate is plotted. Starting from this point, the three change vectors are plotted. d wt , d ewt and dbof the three ventilation methods. Additionally, the direction vector is drawn. d shouldA vector from the interior point to the point with the minimum permissible humidity at the maximum permissible temperature. This vector is the target climate change vector. 5. Ventilation is carried out using the ventilation method that is available and best matches the target climate change vector. For dehumidification purposes, ventilation only occurs if the ventilation method does not point away from the target, i.e., if the dot product of the current and target directions is positive. Additionally, the angle between the current and target directions should not exceed a certain value. The permissible deviation is greater for the dry side than for the humid side of the deviation. Ventilation for dehumidification purposes also occurs if the indoor climate is within the permissible limits and there is no requirement based on air pollutants. 6. The dot product mentioned above is suitable as a measure of the ventilation intensity. 7.If none of the available ventilation methods offers a clearly positive benefit, but ventilation is still necessary for pollutant control, the ventilation method with the largest positive scalar product in relation to the objective will be used. 8. If none of the available ventilation methods has a positive scalar product, but ventilation is still necessary for pollutant control, the method with the largest scalar product will be used. In this case, that is the method with the least negative scalar product. 9. If the room temperature, or, depending on the priority, a surface temperature, falls below the permitted minimum, a heater can be activated. If the room temperature, or, depending on the priority, a surface temperature, exceeds the permitted maximum, an air conditioner with a heat pump (e.g., a split air conditioner) will be activated. 10. If the relative humidity in the room falls below the permitted minimum, humidification can be used.If the relative humidity in the room, or, depending on the priority, the surface humidity, exceeds the permissible maximum, a dehumidifier or, if necessary, a split air conditioner in dehumidification mode should be switched on. 11. If the relative humidity of the supply air... φ TO , surface moisture φ OF or the surface humidity in relation to the supply air φ OF,ZU are greater than the maximum permissible surface moisture at at least one point in the interior and the ventilation system specifically moisturizing If the humidity-controlled ventilation system is affected, it should be deactivated. Applying all three criteria is the strictest option. Depending on the situation, it may be possible to disregard one or two of the criteria. The ventilation system has a humidifying effect if the specific humidity of the supply air entering the interior is higher at the point of entry than the specific humidity of the air exiting the interior. Preferred embodiment

[0025] The preferred embodiment consists of using a commercially available comfort ventilation unit with heat recovery and bypass. The piping and instrumentation flow diagram Fig. 2 This shows such an arrangement. Here, the numbers 1 represent sensor for outdoor air humidity and temperature, 2 outdoor air, 3 exhaust air, 4 bypass duct, 5 optional sensor for supply air humidity and temperature, 6 building volume, 7 exhaust air, 8 sensor for room humidity and temperature, 9 supply air. For climate symbols, see [reference to climate symbols]. Fig. 3 .

[0026] In practice, the invention is combined with other regulations for air pollutants. Accordingly, it works better the fewer air pollutants are produced, the wider the range of permissible climate conditions, and the more time available to achieve the climate target.

[0027] Although it is theoretically possible to operate a ventilation system according to the invention with only two temperature and humidity sensors, in practice at least three sensors should be used, the third of which measures the supply air. This offers several advantages: Even if the outdoor sensor is housed in a radiation-shielded enclosure, there is always a risk of discrepancies between the outdoor air measured at the sensor and the outdoor air drawn in. The outside air may be supersaturated with fog. Many humidity sensors cannot detect this; the calculated specific humidity will then be too low. If the humidity is sufficiently high on one side and the temperature difference between inside and outside is sufficiently large, condensation can occur in the heat exchanger. A supply air sensor detects the resulting discrepancy.

[0028] If the demands on the indoor climate are higher, the invention can be combined with other devices such as heaters and dehumidifiers. The invention ensures that these energy-intensive devices only run as often and as intensely as absolutely necessary. Mathematical formulation

[0029] A reformulation of the ideal gas law yields the formula for calculating the degree of humidity from relative humidity, temperature, and air pressure: x = M H 2 O M tL ⋅ φ ⋅ E s ϑ p − φ ⋅ E s ϑ

[0030] Humidity is measured in grams of vapor per kilogram of dry air. If the humidity level x in a room is known, only the temperature is needed. ϑ 2 , to establish a relative humidity at any given point 2 φ 2 to calculate. Solving equation 1.1 for φ : φ 2 = x ⋅ p E s ϑ 2 ⋅ M H 2 O M tL + x

[0031] Point 2 can be located in the air or on a surface. By resubstituting equation 1.1, but using the temperature and relative humidity from that equation, this formula can be simplified. The humidity level then disappears, the air pressure becomes irrelevant, and the following applies to the surface humidity: φ OF = φ Raum E s ϑ Raum E s ϑ OF .

[0032] The basic position vectors for the state of the outside air, the room air, and the optimal climate are defined: r → AU = T AU φ AU r → AB = T AB φ AB r → ZU = T ZU φ ZU r → opt = T max φ min

[0033] Next, the direction in which the three ventilation modes act is defined. Bypass and free ventilation have the following change vector: d → B = r → ZU − r → AB = r → AU − r → AB = T AU − T AB φ AU − φ AB

[0034] The most important characteristic of a heat exchanger is its heat recovery rate relative to the outside air. η = T ZU − T AU T AB − T AU

[0035] With her Calculate the supply air temperature: T ZU,calc = T AU - η · ( T AU - T AB ).

[0036] A pure heat exchanger with η WT It therefore works as follows: d → WT = r → ZU , calc − r → AB = 1 − η WT T AU − T AB φ x AU ; T AU − η WT ⋅ T AU − T AB − φ AB

[0037] A Enthalpy heat exchanger with heat recovery rate η 1 E It also has a moisture return value. η 2 E Regarding the outside air: η 2 = x ZU − x AU x AB − x AU

[0038] With her The humidity level of the supply air can be calculated: X ZU,calc = x AU - η 2 · ( x AU - x AB ).

[0039] An enthalpy heat exchanger works as follows: d → E = r → ZU , calc − r → AB = 1 − η 1 E T AU − T AB φ x AU − η 2 E ⋅ x AU − x AB ; T AU − η 1 E ⋅ T AU − T AB − φ AB

[0040] The values ​​for heat loss and humidity loss are listed in the data sheet for each ventilation unit. However, they can also be calculated based on the effective temperatures.

[0041] As long as the current room climate is within the target range, the point with the maximum temperature and minimum humidity is targeted. The desired direction is therefore: d → soll = r → opt − r → AB

[0042] However, if the actual climate is outside the target range, the priority shifts in favor of the factor that deviates. This prioritization is carried out with c Tfor the temperature and c φ The factors are shown for humidity. c T and c φ are significantly above 1. The prioritization leads to a reversal of the desired direction: d → ziel = d → soll + c T ⋅ H T AB − T max T max − T AB + H T min − T AB T min − T AB c φ ⋅ H φ AB − φ max φ max − φ AB + H φ min − φ AB φ min − φAB

[0043] H() is the Heaviside function, which has the value 1 for all arguments greater than zero and the value 0 otherwise. d goal This is referred to in the requirements as the target climate change vector.

[0044] Ultimately, the fundamental benefit arises from the scalar product of the ventilation process's change vector and the target climate change vector. Since temperatures would be multiplied by percentages in the scalar product, a correction factor is needed to make the temperature dimensionless and to account for the weighting between temperature and humidity. Let the scaling factor be... cs This is called the scale vector. cs created: c s → = ° C − 1 c s

[0045] Thus, we obtain the scalars for the basic benefit of the three ventilation methods. a b = d → b ∘ c s → ⋅ d → ziel ∘ c s → a wt = d → wt ∘ c s → ⋅ d → ziel ∘ c s → a ewt = d → ewt ∘ c s → ⋅ d → ziel ∘ c s → .

[0046] The circular operator o represents the Hadamard product, the element-wise multiplication. Negative values ​​indicate that the angle between the ventilation method and the target is greater than 90°, meaning the ventilation method is acting in the wrong direction.

[0047] The dot product produces respectably positive values ​​for large amounts, but angles almost perpendicular to the target still yield impressively positive results. Due to the non-linear nature of humidity, it is hardly worthwhile to ventilate for dehumidification purposes at these values. The cosine of the angle between the ventilation method and the target is calculated as follows: cosα x = a x d → x ∘ c s → ⋅ d → ziel ∘ c s → , where the index x here represents the three ventilation methods b, wt and ewtIf the ventilation direction deviates more significantly from the target climate change vector, one can be more tolerant towards the dry side than towards the humid side. cos α However, it is the same for angles less than 0 as for angles greater than 0. Therefore, for each type of ventilation, we also consider whether it increases or decreases the relative humidity. Mathematically: r x = sgn d x , 2

[0048] Using the signum function, you get +1 if the ventilation method increases the relative humidity, and -1 if it reduces it. Scaling factor

[0049] The scaling factor cs Describes the equivalence of relative humidity and temperature. It can be derived from the gradient of relative humidity with respect to temperature. ∂ ∂ T φ x T It is formed and, at typical room temperatures and humidity levels, ranges between 20 and 60. In other words: SinksA change in relative humidity of 0.01 (1%) is equivalent to a temperature of 0.2°C to 0.6°C at the same humidity level. higher Temperature and vice versa. The exact value is not critical. Equation 1.2 can be derived by differentiating and substituting Equation 1.1. c s : = E s T d d T E s T ⋅ φ ⋅ 1 K .

[0050] The factor 1 / K makes the derivative dimensionless so that a scalar product can be calculated. The sign of cs This is not relevant for the further calculation, especially of equation 1.13, since the factor is later multiplied by itself. Angle tolerance

[0051] When assessing whether a ventilation method is still useful, values ​​for cos prove to be relevant for deviations on the drying side. αA range between 0 and 1 / 2 is considered reasonable, meaning deviations up to 60° or even 90° are still useful. On the humidifying side, it is recommended to set the values ​​somewhat closer and discard the ventilation method if the deviation is greater than 45° or the cosine is less than 2 / 2 is. Surface moisture

[0052] Since it is difficult to directly measure surface humidity (also called water activity), the wall or floor temperature is measured using one or more temperature sensors on the interior surfaces. Subsequently, the existing room air sensor (8 in Fig. 2 ) from which one or more relative surface humidityes or water activities φ OF calculated. This is done using equation 1.3.

[0053] In practice, it has been shown that two temperature sensors provide good readings: One is placed on the inside of an exterior wall at the transition to the ground. This is often the coldest point in summer and therefore the one most susceptible to surface moisture. The other sensor is located on the inside of the exterior wall at the top, where it is often coldest in winter. The coldest point has the highest relative surface humidity and is therefore crucial for the control system.

[0054] If, instead of the humidity level of the room, the humidity level of the supply air is used, one obtains the moisture content that the freshly entering supply air can have when it encounters the coldest surface. This simplification applies analogously to section 1.3. φ OF , ZU = x ZU ⋅ p E s ϑ OF ⋅ M H 2 O M tL + x ZU = φ ZU ⋅ E s ϑ ZU E s ϑ OF

[0055] Depending on the arrangement of the supply air and the position of the coldest spot, it is unlikely that the freshly entering supply air will hit the coldest spot directly. However, as a conservative assumption, it is advisable to shut off the ventilation if... φ OF,ZU > φ max and the incoming air has a humidifying effect. This is the case when it is so much warmer and more humid outside that the maximum permissible relative humidity would be immediately exceeded.

[0056] In winter, however, even if the ventilation system with heat exchanger dehumidifies, poorly insulated walls and the resulting low surface temperatures can still lead to an exceedance of the maximum surface humidity. In this case, it makes sense to run the ventilation system in parallel with the heating or dehumidifier.

[0057] Instead of the maximum surface humidity, the second highest value, a quantile, the mean, or the median can also be used to block ventilation. This makes particular sense when more than two sensors are present and one can accept locally conducive conditions for mold or rust growth. Ventilation units without bypass

[0058] If a ventilation unit without a bypass is used, there are several ways to achieve an equivalent effect: A bypass can be implemented using an additional window motor. To do this, the exhaust air fan is simply switched off. The exhaust air is then blown out through the window. The supply air fan continues to run, forcing the outside air to pass through the filter, thus ensuring clean supply air. This would not be the case with the reverse operation. Instead of a window motor as in the first list item, a damper actuator can also be installed in a wall penetration. This offers advantages in terms of personal safety. If several decentralized ventilation units are used without a bypass, only the supply air fan should run in one group, and only the exhaust air fan in the second group. The number of units per group can vary, but the total exhaust air volume should approximately equal the total supply air volume.With at least one heat exchanger and one enthalpy heat exchanger ventilation unit, not only can a bypass be implemented, but the use of ventilation can also be expanded and the piping effort may be reduced. Combination with windows, doors and gates

[0059] Air exchange can be effectively and energy-efficiently achieved or supported by opening windows, doors, and gates. This can be done in various ways: A display can inform room occupants that conditions are now favorable for window ventilation. They then automatically open and close windows, doors, and gates. The resulting air exchange is often greater than what a ventilation unit can provide, and no energy is consumed while the windows, doors, and gates are open. Automatic doors and gates typically close after a certain waiting period when the comfort sensor (usually a radar sensor) no longer detects a person or vehicle. They open fully in summer, while in winter a reduced opening can be set to minimize heat loss.

[0060] It is possible to integrate the doors and gates into the control system by adjusting the opening width and waiting time to the climate. This also protects the drives, as they run fewer cycles and cover shorter distances.

[0061] Air exchange through windows, doors, and gates is accelerated when the direction of the outside airflow is optimal for bypass ventilation. The criteria are the same as for mechanical ventilation (positive dot product, angle within certain limits). Air exchange is forcibly limited when the dot product is negative. Dynamic behavior

[0062] The absolute and specific humidity, as well as the temperature and dew point, typically decrease slowly during the night before rising rapidly and sharply at sunrise. This is clearly visible in the gradients of these values.

[0063] When the humidity gradients turn positive (typically in the morning), you shouldn't ventilate if you want to dehumidify. Because ventilation causes the indoor humidity to follow the outdoor humidity with a time lag, both values ​​would rise in parallel.

[0064] To obtain a reliable humidity gradient signal, a signal filter based on the humidity value is advisable. A low-pass filter is suitable for this purpose, with a cutoff frequency between one and twelve hours, preferably three to five hours. This frequency filters the signal sufficiently without causing an unacceptably long delay.

[0065] It's not necessary to keep the ventilation system completely closed with a positive gradient; a certain period of time is sufficient. After about an hour, the difference in specific humidity is so great that ventilation would cease anyway.

[0066] A very similar effect can be achieved with a digital timer that calculates sunrise. The ventilation is blocked for approximately one hour (10 minutes to 2 hours) shortly after sunrise (0-30 minutes). Prolonged cold and damp periods

[0067] Unfortunately, there are periods when the benefits of ventilation systems are negative for several days. This is the case, for example, in autumn when it is cool and damp. If a minimum air exchange is desired and the climate control settings are configured to generally dehumidify, then on such days, ventilation should preferably take place when the humidity is lowest. Typically, this is the time before sunrise. So, if you want to ventilate for n hours, you should do so during the n Hours before Sunrise. Combination with solar air collectors

[0068] The invention can be effectively combined with solar air collectors, provided a ventilation unit with a bypass is used. The air collector's outlet is connected to the ventilation unit's outside air inlet. The increased temperature allows for more frequent switching to the advantageous bypass mode; statistically, the ideal scenario of warm and dry outside occurs more often. Integration into monoblocks

[0069] Monoblocks are ventilation units (similar to...) Fig. 2 ), which are equipped with heating and cooling coils as well as a humidifier. They can combine outside air and recirculated air operation. When the invention is used with a monoblock as hardware, it leads to a reduced use of the heating and cooling coils and thus saves energy. Channel sensors for outside air and exhaust air

[0070] Instead of an outdoor and a room sensor, duct sensors can also be used in the outdoor air intake and exhaust air intake. When the system is off, it must be purged periodically until the duct sensors display reasonable readings. During this purging process, unsuitable air may enter the building, and the optimal time for energy-efficient ventilation may be missed. Therefore, it is best to use both freestanding and duct sensors. The freestanding exhaust air sensor is referred to as the room sensor in this document. The freestanding sensors are active when the system is off and during purging; the duct sensors take over afterward.

[0071] One advantage of duct sensors (i.e., sensors in the ducts for exhaust air or air drawn in from outside) is that they can be integrated into the ventilation unit, thus eliminating additional installation effort. On the other hand, they only provide valid readings in flowing air, i.e., when the ventilation system is running and air is flowing both outwards and inwards. For a system where the sensors are also required to provide valid readings when the system is stationary, it is advantageous to position the sensors so that they measure parameters in both the outside and inside air. This means the sensors are positioned separately at appropriate locations inside and outside the building. Starting values ​​for supply air humidity and temperature

[0072] The process involves various parameters such as supply air humidity and temperature. However, these values ​​are unknown when the ventilation system is stationary. Therefore, calculated values ​​based on assumed heat recovery and humidity figures are used as a starting point. After the system has been running for a few minutes, the system can switch to the duct sensors, if present. counter

[0073] With today's fan controllers, the electrical power is known quite precisely. Because the systems are calibrated during commissioning, the airflow at different speeds is also known quite accurately; larger systems often have a volume flow sensor.

[0074] The ratio of electrical power to airflow is the SFP, expressed in energy per unit of airflow.

[0075] The absolute humidity and temperature of the supply and exhaust air are also known. The current humidification and dehumidification capacity can be calculated from the difference between the absolute humidity of the supply and exhaust air, multiplied by the volume flow rate. The integral of these values ​​acts as a counter for the water removed and supplied, provided positive and negative values ​​are recorded separately. Such a counter can reassure customers, as in practice, significantly more water is removed than supplied.

[0076] The available data allows us to calculate the specific enthalpy of the supply and exhaust air. While enthalpy can also be determined using sensors in the outside and exhaust air, this is less practical. Multiplying the difference in specific enthalpy by the density and volume flow rate yields the heat flux, and the integral of this gives the energy, which can be measured per day, week, month, and year.

[0077] The ratios of heat quantity, dehumidification capacity and energy consumption are of interest for monitoring energy efficiency: the performance figures COP, EER and MRE. Consideration of efficiency

[0078] If a very efficient ventilation system is located in a relatively small building volume, the energy expenditure for ventilation may be disproportionate to the benefit in the form of supplied heat or removed moisture.

[0079] It is therefore quite possible to limit the airflow to ensure a certain efficiency, measured in volume of water removed per electrical power or heat supplied per electrical power or a combination of the two values.

[0080] It is also possible to vary the airflow to maximize efficiency. However, this mode has the disadvantage that efficiency is often greatest at low airflow rates, and therefore also at low heat gains and dehumidification capacities. Heat exchanger replacement

[0081] For indoor spaces with a low upper temperature limit T max In the height of summer, an enthalpy heat exchanger package can be used to minimize moisture input when ventilation is necessary for pollutant reduction. The control system simply needs to be informed which package is installed.

[0082] It is also possible to replace a summer package, a plate heat exchanger and an enthalpy heat exchanger with a drive or robot.

[0083] Alternatively, there are heat exchangers with variable moisture recovery, for example rotary heat exchangers. With these, more or less moisture can be recovered or kept out by changing the rotational speed, which can be combined with the control system according to the invention. Specific target climate areas

[0084] Unless the target climate is as in Fig. 1 If the area is a rectangle, the climate target point is determined as follows: In the diagram Fig. 1 a straight line φ = T (Diagonal) approach the area with the target climate from above. The first intersection point is the climate target point. The diagonal represents the equivalence of temperature and relative humidity. If the target climate is defined by the diagonal φ = T To limit the line, one takes the end with the higher temperature. Variations of the preferred embodiments

[0085] From the preceding description of preferred embodiments, modifications and additions are accessible to the person skilled in the art without leaving the scope of protection of the invention as defined by the claims.

[0086] For example, the following are conceivable: If the actual climate deviates from the target range for a parameter such as humidity or temperature, the target direction is adjusted in a different way to bring this parameter back into the target range more quickly, for example, by rotating it by an angle. Additional climate parameters are defined for the target climate zone, such as enthalpy and specific humidity. The boundaries of the target climate zone are defined by lines, each representing a climate parameter as a function of one or more of the other climate parameters. Different dependencies can be chosen for the upper and lower values ​​of a climate parameter; in particular, one value can also be constant. Instead of the normal scalar product... a · b = a · b cos α A definition is used that places greater emphasis on direction, e.g. a · b = ab cos n< α with n > 1. glossary

[0087] absolute humidityDimension grams of steam per cubic meter of air, changes slightly when flowing through a heat exchanger; air pressure does not need to be measured or assumed. Humidity level The unit of measurement is grams of water vapor per kilogram of dry air; it does not change when flowing through a heat exchanger. The calculation requires knowledge of the atmospheric pressure. wet-bulb temperature The wet-bulb temperature is the lowest temperature achievable through evaporative cooling. It is a measure of comfort at higher temperatures. Air pollutants With regard to the invention, CO2, dust, VOCs (which include musty odors) and radon are particularly relevant. ventilation system Total of all installed ventilation components, i.e., ventilation unit with ductwork, dampers, registers, etc. ventilation unit The central component of the ventilation system is usually manufactured in a factory and includes fans, controls, sensors, and often a heat exchanger. relative humidityDimensionless quantity expressed as a percentage of the saturation steam quantity at a given temperature; changes significantly when flowing through a heat exchanger. Re-moisture value is a measure of the specific humidity recovered by an enthalpy heat exchanger. Heat recovery rate also called heat availability rate or temperature change rate, is a measure of the temperature recovered by a heat exchanger.

[0088] Summer package Design for use in ventilation units with external dimensions similar to a plate heat exchanger. Since there is only one plate, it prevents heat exchange.

[0089] specific humidity The unit of measurement is grams of water vapor per kilogram of moist air; it does not change when flowing through a heat exchanger. The calculation requires knowledge of the atmospheric pressure. Acronyms

[0090] AWAY Exhaust air AU Outside air b bypass COP Coefficient of Performance EER Energy Efficiency Ratio ewt Enthalpy heat exchanger fL free ventilation FO Exhaust air MRE Moisture Removing Efficiency SFP specific ventilation performance wt Heat exchanger TO Supply air Formula symbols

[0091] It Saturation vapor pressure, temperature-dependent only; if temperature is given as a parameter: at the specified temperature M H 2 O molar mass of water, 18.02 g mol -1< M tL molar mass of dry air, 28.96 g mol -1< T max upper limit of the target temperature T min lower limit of the target temperature η efficiency φ OF Relative humidity of the surface, water activity φ space relative humidity of the air in the room, measured in a well-ventilated, not too cold location φ TO relative humidity of the supply air φ max upper limit of the relative target humidity φ minlower limit of the relative target humidity φ relative humidity ϑ Temperature in degrees Celsius d Change vector a basic benefit, scalar product of the change vector of the process and the target climate change vector p Air pressure x humidity level, mass of vapor per mass of dry air

Claims

1. Method for adjusting a climate in an interior space, characterized • in that a desired climate zone is defined which is delimited by lines which are given by lower and upper limit values of desired climate parameters, wherein desired climate parameters are at least an upper and a lower temperature, in each case as a function of the relative air humidity or as a constant value, and an upper and a lower relative air humidity, in each case as a function of the temperature or as a constant value, and wherein the climate of the interior space lies in the desired climate zone if at least the temperature of the interior space lies in the range of lower temperature to upper temperature at the prevailing air humidity and the relative air humidity lies in the range of lower air humidity to upper air humidity at the respective temperature, • in that the relative air humidity and the temperature of air are determined at least at in each case one measuring point - outside the interior space and / or in flowing air conducted into the interior space and - in the interior space and / or in flowing air conducted to the outside from the interior space • and in that ventilation is carried out, wherein air is exchanged between the interior space and an environment outside the building or vehicle if a change in the climate of the interior space in the direction of a predefined climate target point in the desired climate zone or from a state outside the desired climate zone in the direction of the limits of the desired climate zone is brought about by the ventilation, wherein the climate target point is defined at least by a target temperature and a target humidity, even if the relative air humidity and the room temperature in the interior space lie within the desired climate zone, in order to reduce the energy consumption during the room climate adjustment by the extended use of ventilation.

2. Method according to claim 1, characterized in that the relative air humidity and the temperature of air are determined at least at in each case one measuring point outside the interior space and in the interior space.

3. Method according to any one of claims 1 to 2, characterized in that one, two or three of the following conditions apply: a) the difference between lower and upper temperature is at least 2°C, preferably at least 4°C, further preferably at least 6°C; b) the target temperature is at most upper temperature and at least upper temperature less than half, preferably less than a third, further preferably a quarter, further preferably an eighth and even further preferably a tenth of the difference between upper and lower temperature, and is most preferably approximately equal to the upper temperature; c) the target humidity is at least the lower relative air humidity and at most the lower air humidity plus half, preferably plus a third, further preferably plus a quarter, further preferably plus an eighth and even further preferably plus a tenth of the difference between upper and lower relative air humidity and is in particular preferably approximately equal to the lower relative air humidity.

4. Method according to any one of claims 1 to 3, characterized in that the interior space climate lies in the desired climate zone if each climate parameter lies within the desired climate zone.

5. Method according to anyone of claims 1 to 4, characterized in that ventilation is carried out if the relative humidity of the supply air is less than the relative humidity in the interior space as long as the supply air temperature lies in the predefined temperature range from lower temperature to upper temperature.

6. Method according to any one of claims 1 to 5, characterized in that the desired climate zone is given exclusively by the upper and the lower temperature and the upper and the lower air humidity.

7. Method according to any one of claims 1 to 6, characterized in that at least two of the following three methods for ventilation are available as air exchange between interior space and environment: • air exchange substantially by discharging air from the interior space and inflow of air from the environment, wherein an outgoing air flow or an inflow air flow arises, without heat exchange between the outgoing air flow and the inflow air flow or with exchange by direct contact of the two air flows; • air exchange via a heat exchanger which permits only heat exchange; and • air exchange via an enthalpy heat exchanger which permits, in addition to the heat exchange, also an exchange of steam; wherein for each of the available air exchange methods it is determined which change of the relative humidity and of the temperature the air exchange method brings about, and that air exchange method is used which brings about the greatest change in the direction of an interior space climate given by the upper temperature and the lower humidity.

8. Method according to claim 7, characterized in that the change is determined as the sum of change of the relative humidity and change of the temperature.

9. Method according to claim 7, characterized in that a desired climate change vector from the current room climate to the climate target point is determined, wherein climate states such as room climate and climate target point are represented as vectors with the climate parameters as components, that the desired climate zone is given at least by the upper temperature and the lower humidity and wherein, as the result of a scalar product of the change vectors of the air exchange methods with the desired climate change vector, a utility of each air exchange method is determined, and that the air exchange method is used which has the highest utility, and preferably no ventilation method is used which yields a scalar product less than or equal to 0 (zero), corresponding to an angle of its change vector with the desired climate change vector greater than or equal to 90°.

10. Method according to claim 9, characterized in that • if the angle between change vector of the respective method and the desired climate change vector lies between 0° and a limit angle, the method with the greatest scalar product is selected in order to preferably use methods in this angle range, • if no method fulfils the above criterion, but the angle between change vector of the respective method and the desired climate change vector lies between the limit angle and 90°, the method with the greatest scalar product is selected, • otherwise ventilation is carried out only with a ventilation method, preferably with a ventilation method with the greatest scalar product, if ventilation is unavoidable.

11. Method according to claim 10, characterized in that at least one of the following measures is used in order to achieve a preference for ventilation methods which reduce the humidity: • in the event of deviations of the change vector of the respective method from the desired climate change vector to the drying side, a first limit angle is predefined and, in the event of deviations to the wetting side, a second limit angle is predefined which is less than the first limit angle, wherein first and second limit angles preferably differ by at least 10°, and further preferably the first limit angle lies in the range of 45° to 90° and the second limit angle lies in the range of 45° to 60°, in each case including the range limits; and • to the cosine of the angle between desired climate change vector and change vector of the ventilation method, a function is applied which brings about a faster drop in the value of the absolute value of the cosine if the ventilation method has a wetting effect, preferably an exponentiation with powers of at least 2, an exponentiation or a mixed form thereof.

12. Method according to any one of claims 7 to 9, characterized in that in a state in which one of the climate parameters lies outside the desired climate zone, that which brings about the greatest change of this climate parameter toward the desired climate zone is used in the selection of the ventilation method.

13. Method according to claim 12, characterized in that that component of the change vector of each air exchange method which corresponds to the climate parameter which lies outside the desired climate zone is multiplied by a weighting factor which is greater than one in order to weight the change of the climate parameter lying outside the desired climate zone higher in the selection of the air exchange method.

14. Method according to claim 9, characterized in that in a state in which one of the climate parameters lies outside the desired climate zone, that which brings about the greatest change of this climate parameter toward the desired climate zone is used in the selection of the ventilation method, and that at least one of the ratios between that component of the change vector of each air exchange method which corresponds to the climate parameter which lies outside the desired climate zone and in each case another component of the change vector is multiplied by a weighting factor which is greater than one in order to weight the change of the climate parameter lying outside the desired climate zone higher in the selection of the air exchange method.

15. Method according to any one of claims 13 to 14, characterized in that the weighting factor has a value in the range of 1.5 to 100, preferably 2 to 50, further preferably 5 to 10.

16. Method according to any one of claims 1 to 15, characterized in that air exchange methods which fulfil at least one of the following conditions are not used: • The method does not lead to a change of the climate of the interior space in the direction of a preferred combination of climate parameters, preferably the climate target point, wherein the preferred combination of climate parameters comprises at least preferred values for the temperature and the humidity for the interior space. • The method leads to an increase of the specific humidity in the interior space and the value of the surface humidity φOF in the interior space at a coldest point is equal to or greater than a predefined limit value of the surface humidity, preferably in addition the surface humidity in relation to the supply air φOF,ZU in the interior space at a coldest point is equal to or greater than the predefined limit value, and further preferably in addition the relative humidity of the supply air φZU is equal to or greater than the predefined limit value, wherein the limit value of the surface humidity is one of the following: - the relative humidity of the climate target point; or - the value at which mold formation starts, preferably 75%; or - the value at which rust formation starts, preferably 65%, in order to avoid rust damage in particular in reinforced concrete or steel structures.

17. Installation for carrying out the method according to any one of claims 1 to 16, characterized in that sensors are present in order to determine at least the humidity and the temperature in the interior space, in the environment and in the supply air, in order to be able to detect the climate parameters of air used for ventilation both generally and specifically in the inflow air flow.

18. Installation according to claim 17, characterized in that at least one of the following sensors is present: • sensor of the supply air in the region between ventilation installation and exit of the supply air into the interior space; • sensor of the outside air in a weather shelter for protection against solar radiation; and • sensor of the outside air in the vicinity of an intake opening of the outside air for the ventilation installation.

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