EP2405210A1 - Arrangement for room air cooling - Google Patents

Abstract

The arrangement has a temperature sensor (9) and a humidity sensor for detecting relative humidity at a to-be-cooled room. The humidity sensor is arranged in direct proximity to flow pipe lines of a coolant circuit in rooms, which are not identical with the to-be-cooled room. A regulating unit receives measuring values of the humidity and temperature sensors by signal connections and determines flow temperature. The regulating unit adjusts temperature of a to-be-cooled medium in the flow pipe lines by a signal connection to a mixing device. An independent claim is also included for a method for operating an arrangement for cooling a room in a building.

Description

The subject matter of the present invention is an arrangement for cooling buildings with increased internal inertia of the temperature and moisture compensation. This applies in particular to buildings with a high proportion of wood, and here in particular older houses, houses with floorboards or wooden floor coverings or beamed ceilings. Furthermore, a procedure for operating this arrangement is presented.

Cooling surfaces are usually arranged in buildings in or on walls, ceilings or floors. They have supply lines which transport the cooling medium to the cooling surfaces and return lines, which transport the heated cooling medium away from the cooling surfaces. Frequently, cooling plates are still arranged on the cooling surfaces to increase the heat exchanging surface.

The indoor temperature envisaged in the rooms is usually adjusted to thermostats arranged in these rooms, which ensure that the room is cooled until the set temperature is reached. The thermostats pass on the preset temperature to control devices in the room or one or more central control devices, which determine the flow temperature and the flow rate.

Advanced systems monitor the humidity in the room or just the condensation near the heatsinks. At these points, the minimum temperature in the room can be expected. In order to avoid a condensation of water, the cooling is interrupted when falling below the dew point and resumed after a temperature rise. Further developed systems continue the cooling with increased flow temperature in order to avoid falling below the dew point temperature. The tempering control system according to DE 10 2006 061 801 go one step further. In this system, a moisture meter is placed in the room next to a temperature sensor. At the start of cooling, the system determines from temperature and humidity a minimum permissible temperature which is above the dew point temperature. The flow temperature is now chosen so that it is above the minimum permissible temperature and thus prevents condensation. Temperature sensors in the vicinity of the cooling surfaces monitor the temperature actually reached and influence the flow temperature via a control device. In preferred developments, the flow temperatures of individual cooling surfaces can be regulated separately.

The suitability of the systems described for modern buildings with good internal temperature and humidity compensation is indisputable. However, the use of these systems is problematic for old buildings and other buildings that are very heterogeneous in their building structure and separated cavities and a variety of organic materials and building materials. Such buildings often have only partially solid exterior walls. The floors or ceilings are often supported by wooden beams and the lines for heating or cooling are preferably laid in wood-borne cavities in floors, walls or ceilings. These cavities often form a sequence of separate rooms or areas in which different climatic conditions can prevail and their temperature and moisture balance is hindered. The buildings thus have an increased inertia of the temperature and humidity compensation. The cavities can not be protected from local underruns of the dew point by prior art arrangements. In addition, wood has a different equilibrium moisture content depending on the relative humidity. If, therefore, there is an increased relative humidity over a longer period due to the lowered temperature, the wood starts to absorb water. Accordingly, swelling phenomena begin in the wood. In extreme cases, it can lead to mold or other fungal attack. It can thus be seen that even humidity levels that are not yet close to saturation can have negative effects on wood. It is generally assumed that the relative humidity of old timbers should not exceed 70% in the long term to avoid damage.

It is therefore an object to provide a cooling system that is suitable for buildings with increased inertia of the temperature and humidity balance and the building fabric protects against negative effects in a cooling. It is not only in the space to be cooled, but also on the entire route of the coolant piping or critical sections in rooms whose temperature and humidity compensation is hindered, a predetermined relative humidity not be exceeded.

According to the invention, this object is achieved with an arrangement according to claim 1. Advantageous developments are disclosed in the dependent claims. An advantageous mode of operation of the arrangement is shown in the dependent method claim.

In the following, the presentation of technical components that would be added to the skilled person due to his knowledge of the arrangement, is omitted. Such may be, for example, temperature sensors in flow and return and the various reservoirs, throttling and control valves, circulating pumps, etc.

The arrangement according to the invention has one or more humidity sensors in the immediate vicinity of the piping (preferably to the flow pipe) of the coolant circuit even in rooms that are not identical to the space to be cooled. These humidity sensors pass on their measured values to a control unit which, together with the Processes measured values from the room to be cooled and determines a flow temperature that avoids exceeding the maximum permissible humidity in all rooms with humidity sensors. The maximum permissible air humidity can be specified separately for the individual humidity sensors in a preferred embodiment. This makes it possible to allow different levels of relative humidity in rooms subject to regular ventilation than in rooms that are largely closed. Such enclosed spaces can be used in addition to actually used spaces and cavities in the floor, walls or ceilings, through which the piping is performed. Since there is usually a relatively low exchange of air, there is a certain inertia of the system. Thus, in summer, at relatively high temperatures, air at a relative humidity will slowly penetrate into such a room, resulting in a very high relative humidity due to the cooling effect of the piping of the system, as the temperature in the room decreases. Due to the low air exchange with the outside air, this condition is only gradually reduced. In cooling processes, care must now be taken that this does not fall below the permissible relative humidity in such rooms or even that the dew point is reached. This monitoring takes place by means of the control unit.

1. a. mindestens einen zu kühlenden Raum, in und/oder an dessen Wand und/oder Boden und/oder Decke eine oder mehrere Kühlflächen angeordnet sind
2. b. mindestens eine Vorlaufrohrleitung zur Zuführung eines kühlenden Mediums zu den Kühlflächen und mindestens eine Rücklaufrohrleitung für die Abführung des kühlenden Mediums von den Kühlflächen
3. c. mindestens ein Reservoir A eines kühlenden Mediums, dessen Temperatur kleiner oder gleich der Temperatur in der Vorlaufrohrleitung ist
4. d. mindestens ein Reservoir B eines kühlenden Mediums, dessen Temperatur größer oder gleich der Temperatur in der Vorlaufrohrleitung ist
5. e. mindestens eine Mischvorrichtung an der Vorlaufrohrleitung zur Mischung des kühlenden Mediums aus Reservoir A und Reservoir B
6. f. mindestens einen Temperatursensor und mindestens einen Feuchtesensor zur Erfassung der relativen Luftfeuchte im zu kühlenden Raum
7. g. mindestens einen Feuchtesensor in unmittelbarer Nähe zu den Vorlaufrohrleitungen des Kühlmittelkreislaufes in Räumen, die nicht mit dem zu kühlenden Raum identisch sind
8. h. mindestens eine Regelungseinheit, die über Signalverbindungen Messwerte der Feuchte- und Temperatursensoren empfängt, diese verarbeitet, eine Vorlauftemperatur ermittelt und über eine Signalverbindung zur Mischeinrichtung die Temperatur des kühlenden Mediums in der Vorlaufrohrleitung einstellt.

Overall, the device according to the invention thus has at least the following components:

1. a. at least one space to be cooled, in and / or on the wall and / or floor and / or ceiling, one or more cooling surfaces are arranged
2. b. at least one flow pipe for supplying a cooling medium to the cooling surfaces and at least one return pipe for the discharge of the cooling medium from the cooling surfaces
3. c. at least one reservoir A of a cooling medium whose temperature is less than or equal to the temperature in the flow pipe
4. d. at least one reservoir B of a cooling medium whose temperature is greater than or equal to the temperature in the flow pipe
5. e. at least one mixing device on the flow pipe for mixing the cooling medium from reservoir A and reservoir B.
6. f. at least one temperature sensor and at least one humidity sensor for detecting the relative humidity in the space to be cooled
7. G. at least one humidity sensor in close proximity to the flow pipelines of the coolant circuit in rooms that are not identical to the room to be cooled
8. H. at least one control unit that receives measured values of the humidity and temperature sensors via signal connections, processes these, determines a flow temperature and adjusts the temperature of the cooling medium in the flow pipe via a signal connection to the mixing device.

Reservoirs A and B may preferably be containers with a cooling medium of different temperatures. But it is also possible that the reservoir A is designed as an output of a heat pump or a heat exchanger. Reservoir B can also be the return of the cooling medium. The setting of the desired flow temperature can then be done for example by mixing return medium to the leading medium. However, the reservoir B may also be the output of a heat exchanger or a heat pump or a heating system.

The target variables of the control are therefore in the operation of the system in addition to the predetermined temperature in the space to be cooled and the relative humidity values on the way the piping to be cooled space.

The control unit processes the measured values of the humidity sensors together with the measured values from the room to be cooled also from the rooms that are not identical to the room to be cooled and determines a flow temperature that avoids exceeding the maximum permissible humidity in all rooms with humidity sensors. This flow temperature is adjusted via the signal connection of the control unit to the mixing device by mixing the cooling media from reservoir A and reservoir B.

Due to the mode of operation, it is possible that under certain circumstances the desired temperature in the room to be cooled is not achieved, or only after a much longer time. However, in this way it is reliably prevented that not only dew point drops and thus condensation phenomena occur, but also that the air humidity values in all monitored piping areas exceed predetermined values. Thus, the building substance, in particular the wood, can be reliably protected against negative effects by the moisture. Since the main purpose is the cooling of living spaces, this represents only a small impairment that the user takes in the interest of preserving the fabric in purchasing.

In a preferred embodiment, temperature sensors are also arranged in spatial proximity to one or more of the moisture meters and also output their measured values to the control unit.

In a further preferred embodiment, the control unit generates a prognosis as to whether the predefined target temperature in the room to be cooled is likely to be reached. The user is advantageously informed via an optical or acoustic message when setting the target temperature for the room and the permissible relative humidities for the air moisture meters in the rooms on the way to the room to be cooled, whether the predetermined temperature is expected to reach.

Advantageously, the control unit is designed as an additional module for retrofitting existing cooling control systems.

The control device of the arrangement is designed as an additional module for a conventional cooling regulator according to the prior art. The module has a number of inputs into which the measuring signals of the moisture meters are fed. In this embodiment, a uniform maximum value for all humidity meters of 70% for the relative humidity is specified on the module. The module has at the output a galvanically isolated actuator in the form of a resistance matrix. The output signal is fed to the outdoor sensor measuring circuit of the conventional cooling controller. The module thus appears in the conventional cooling controller as a simulated external sensor. Based on the signals from the module, the cooling controller regulates the flow temperature to a value that prevents the relative humidity at the individual moisture meters from exceeding the specified value.

• Zur Überwachung der Feuchtigkeit an n Stellen in einem Gebäude werden n resistive Feuchtigkeitssensoren (S1..Sn) verwendet. Diese werden über einen Messstellenumschalter (1) sequentiell auf eine Widerstands-zu-Spannungs-Umsetzerschaltung (3) geschaltet. Das Ausgangssignal des Umsetzers (3) wird auf einen Analog-Digital-Umsetzer-Eingang (4) einen µ-Controllers (5) geführt. Die Software wertet die Messsignale der N-Messstellen (S1..Sn) aus. Entsprechende Feuchtigkeits-Grenzwerte können über ein einfaches Bedieninterface bestehend aus LCD-Display (7) und Menütasten (8) individuell für jede Messstelle (S1..Sn) eingestellt werden. Die Einstellwerte werden im EEPROM des µ-Controllers (5) abgespeichert, so dass diese auch nach Spannungsausfall erhalten bleiben.
• Bei Überschreitung eines Feuchtigkeitsgrenzwertes wird der Widerstand im Messkreis des Temperatursensors (9) der Mischersteuerung (11) durch ein mit Relais geschaltetes Widerstandsnetzwerk (12) verändert und die Mischersteuerung (11) veranlasst, die Vorlauftemperatur anzuheben. Der Widerstand im Temperaturmesskreis kann durch Einschleifen von Zusatzwiderständen erhöht (Relais k3, k4) oder durch Parallelschalten von Zusatzwiderständen verringert werden (Relais k1, k2). Welche Art der Beeinflussung erforderlich ist, hängt von der Art des Temperatursensors (9) ab.
• Im vorliegenden Fall besitzt das Widerstandsnetzwerk (12) nur 1 Stufe. Für anspruchsvollere Regelalgorithmen kann es jedoch sinnvoll sein, den Widerstand des Temperaturmesskreises in mehreren Stufen zu beeinflussen.

In detail, this is realized as follows:

• To monitor the humidity at n points in a building, n resistive humidity sensors (S1..Sn) are used. These are connected via a measuring point switch (1) sequentially to a resistance-to-voltage converter circuit (3). The output signal of the converter (3) is fed to an analog-to-digital converter input (4), a μ-controller (5). The software evaluates the measuring signals of the N measuring points (S1..Sn). Corresponding humidity limit values can be set individually for each measuring point (S1..Sn) via a simple user interface consisting of an LCD display (7) and menu buttons (8). The setting values are stored in the EEPROM of the μ-controller (5) so that they are retained even after a power failure.
• If a moisture limit value is exceeded, the resistance in the measuring circuit of the temperature sensor (9) of the mixer control (11) is changed by a resistor network (12) switched with relays and causes the mixer control (11) to raise the flow temperature. The resistance in the temperature measuring circuit can be increased by looping in additional resistors (relays k3, k4) or reduced by connecting additional resistors in parallel (relays k1, k2). The type of influence required depends on the type of temperature sensor (9).
• In the present case, the resistor network (12) has only 1 stage. For more demanding control algorithms, however, it may be useful to influence the resistance of the temperature measuring circuit in several stages.

Used hardware components

• Measuring point switch (1): Relay matrix, but also analog switches are possible, which are less expensive and wear-free, but require more complex protective measures against electromagnetic interference, especially against overvoltage,
• μ-Controller (5): μ-controller from ATMEL with rewriteable flash memory as program memory and rewritable EEprom memory as parameter memory as well as integrated ADC inputs (4)
• IO Expander / Driver (6): CPLD for I / O decoding of XILINX, with standard driver ICs as drivers
• Switched resistor network (12): Industrial relay with a high number of switching cycles (> 1,000,000), since here in the measuring circuit of assembled products, electrical isolation via relays is necessary, although analog switches can also implement the functionality. Chip resistors with 0.1% tolerance are used as additional resistors.
• LCD display (7) and control buttons (8): Alphanumeric low-cost display with 1x16 characters 3.5 mm character height, without backlight. 4-button operation (e.g.,>, <, Enter, ESC)
• R / V converter (3): Resistance-voltage converter either as a bridge circuit where voltage- or current-fed R / V converters are also possible
• Power supply: Ready-made switching regulator with potential separation 2000Vrms according to available voltage (mains voltage 230V 50Hz AC or 24V DC)

figure

Fig. 1 represents the circuitry implementation of the embodiment as a block diagram of the controlling components. The sensors (S1..Sn) record the humidity values in different rooms through which the piping of the cooling system leads. One or more of the sensors (S1 .. Sn) are also arranged in the space to be cooled. The measured values of the sensors (S1 .. Sn) are forwarded to the microcontroller (5), which processes them together with the default values entered with LCD display (7) and keyboard (8). Control signals are generated, which together with the temperature value in the space to be cooled, which is detected by the temperature sensor (9), are passed via a resistance network (12) to the mixer control (11), where the flow temperature of the cooling circuit is adjusted.

LIST OF REFERENCE NUMBERS

S1 ... Sn

Sensor 1 to sensor n

k1 ... kn

Relay for switching additional resistors

1

Measuring point switch (relay matrix or analogue switch)

2

power supply

3

R / U converter (resistance-voltage converter)

4

ADC in (input of the analog-to-digital converter)

5

Microcontroller (μ-controller) and peripherals

6

Driver (I / O Expander)

7

LCD display

8th

Control buttons

9

temperature sensor

10

Input temperature sensor

11

mixer control

12

switched resistor network

Claims (7)

Arrangement for cooling rooms in buildings with increased inertia of temperature and humidity compensation, comprising: a. at least one space to be cooled, in and / or on the wall and / or floor and / or ceiling, one or more cooling surfaces are arranged b. at least one flow pipe for supplying a cooling medium to the cooling surfaces and at least one return pipe for the discharge of the cooling medium from the cooling surfaces c. at least one reservoir A of a cooling medium whose temperature is less than or equal to the temperature in the flow pipe d. at least one reservoir B of a cooling medium whose temperature is greater than or equal to the temperature in the flow pipe e. at least one mixing device on the flow pipe for mixing the cooling medium from reservoir A and reservoir B. f. at least one temperature sensor and at least one humidity sensor for detecting the relative humidity in the space to be cooled G. at least one humidity sensor in close proximity to the flow pipelines of the coolant circuit in rooms that are not identical to the room to be cooled H. at least one control unit which receives measured values of the humidity and temperature sensors via signal connections, processes these, determines a flow temperature and adjusts the temperature of the cooling medium in the flow pipe via a signal connection to the mixing device. Arrangement according to claim 1, characterized in that temperature sensors are arranged in the spatial vicinity of one or more of the humidity sensors, which pass on their measured values to the control unit. Arrangement according to claim 1 or 2, characterized in that the control unit is designed as an additional module for the retrofitting of existing cooling control systems. Method for operating an arrangement according to one of the preceding claims, characterized in that the control unit processes the measured values of the humidity sensors from the rooms, which are not identical to the room to be cooled, together with the measured values from the room to be cooled and determines a flow temperature, which avoids exceeding the maximum permissible air humidity in all rooms with humidity sensors, and adjusts this flow temperature via the signal connection to the mixing device by mixing the cooling media from reservoir A and reservoir B. A method according to claim 4, characterized in that the desired temperature for the space to be cooled is predetermined at the control unit. A method according to claim 4 or 5, characterized in that the maximum allowable humidity for rooms is given to the control unit, which are not identical to the space to be cooled, but have humidity sensors. Method according to one of claims 4 to 6, characterized in that the control unit processes measured values which originate from temperature sensors in the vicinity of at least some humidity sensors and generates a prognosis as to whether the desired temperature in the space to be cooled is likely to be achieved.

Images