METHOD AND INSTALLATION FOR VENTILATION OF A PLURALITY OF ROOMS IN A BUILDING

The invention relates to a method for ventilating a building, comprising of:

- drawing in a flow of outside air at a central location in the building,

- dividing the indrawn airflow into a number of partial flows at the central location, and - guiding the partial flows from the central location to a number of rooms in the building, and there blowing them out.

Such a method of ventilation is already known in practice. In the known method outside air is drawn in by a central ventilation device, and there separated by a dividing unit into a number of partial flows which are carried to the different rooms through separate ducts. The amount of ventilation air flowing to each of the rooms is regulated here by adjusting the resistance on the outflow side, so by varying the passage opening of an outflow ornament in the room into which each of the ducts debouches.

Compared to earlier ventilation methods, wherein the indrawn outside air was carried to the different rooms through a shared main duct, and partial flows were separated therefrom at each room, this method has the advantage that the distribution of the ventilation air over the different rooms is considerably more uniform. In the older method the air supply to rooms close to the central location was greater than that to more remote rooms. In addition, the large airflow through the main duct resulted in flow-induced noise, while so-called crosstalk noise, i.e. transmission of sound from one of the rooms to the other rooms, could occur

through the main duct. Finally, the newer method provides the advantage that use can be made of relatively thin ducts which can be accommodated in the building more easily than the earlier, usual main duct. The known method does however still have a number of drawbacks. The regulation of the supply of the ventilation air to the rooms themselves has thus been found to be less than ideal in practice because it is time- consuming and undesirable differences can still occur. This is the result of the fact that, due to a change in the resistance of the outflow opening in one of the rooms, the overall resistance of the system, and thereby the outflow into the other rooms, is also affected. The regulation is further carried out by an engineer, whereby personal preferences and skills may influence the regulation. This regulation, wherein the air supply is often greatly limited, also results in whistling or hissing background noises as a result of airflow through narrow openings. Finally, there is a risk of the regulation being disrupted when a user removes the outflow ornaments, for instance in order to clean them, and then does not replace them in the correct manner.

The invention therefore has for its object to provide a ventilation method of the above described type in which these drawbacks do not occur, or at least occur to a lesser extent. According to the invention this is achieved in such a method in that the division of the indrawn airflow into partial flows at the central location is regulated on the basis of the ventilation requirement of each room. By regulating the division at the central location, it can be set optimally in one operation for all rooms. Furthermore, the ventilation air can flow further without disruption from the central location to the rooms, whereby flow-induced noises are prevented as far as possible. Finally, it is thus

possible to already preset the division, whereby this does not depend on the engineer.

A simple regulation is obtained when the air is drawn in at a substantially constant pressure and the division into partial flows is regulated by setting passage openings between the central location and each of the rooms. For an optimal ventilation it is recommended that used air is extracted from the building, the extracted air is guided from different rooms to the central location, and the used air is collected at the central location and discharged to the outside. By thus also regulating the discharge of used air from the rooms at the central location a good balance is achieved between supplied and discharged air, and thereby an excellent ventilation. The extraction does not otherwise have to take place here from the same rooms into which the ventilation air is blown. Extraction will take place in practice from rooms where the air quality is inferior, so in the case of a house the kitchen, the toilet and the bathroom. The ventilation air will on the other hand be supplied to living areas such as the living room, bedrooms and the like. An air circulation is hereby realized in the house.

The invention also relates to an installation for ventilating a building which is suitable for performing the above described method.

A known ventilation installation comprises a suction device placed at a central location in the building, a number of ventilation ducts leading from the suction device to different rooms in the building, and a dividing unit placed between the suction device and the ventilation ducts. The ventilation device according to the present invention is now distinguished from this known installation

by the presence of means for regulating the dividing unit on the basis of the ventilation requirement of each room.

The dividing unit preferably has at least one inflow opening connected to the suction device and a number of outflow openings connected to the ventilation ducts, the suction device is adapted to maintain a substantially constant pressure in the dividing unit, and the regulating means act on the outflow openings. Due to the constant pressure in the dividing unit the ventilation air can be readily divided into partial flows with the desired flow rate by adjusting the outflow openings.

A structurally simple solution is achieved here when the regulating means comprise controllable valves in the outflow openings. By making use of valves in the dividing unit it is possible to dispense with valves at the position of the outflow openings in the rooms. It is hereby possible to opt for a simple finish therein, where the form no longer need be determined on the basis of technical requirements in respect of the regulation. This can result in the use of outflow ornaments which are not only simpler, but also more attractive than the known outflow grates of valves. In addition, outflow noises are thus prevented, and the regulation is not affected by periodic removal and replacement of the outflow ornaments. The installation according to the invention can advantageously be further provided with an extraction device placed at the central location, a number of return ducts leading from different rooms to the extraction device, a collecting unit placed between the return ducts and the extraction device, and means for regulating the collecting unit on the basis of the ventilation requirement of each room, whereby the extraction of used air from the rooms can also be optimally controlled.

The collecting unit can here be structurally embodied in similar manner as the dividing unit, and thus have at least one outflow opening connected to the extraction device and a number of inflow openings connected to the return ducts, wherein the extraction device is then adapted to maintain a substantially constant pressure in the collecting unit and the regulating means once again act on the inflow openings. The regulating means advantageously then also once again comprise controllable valves, this time in the inflow openings.

In order to nevertheless ensure an optimal division of the ventilation air under different conditions, it is recommended that the regulating means comprise an electronic control unit connected to the valves. The division can thus be adjusted in simple manner at any moment. When the electronic control unit is then further programmable, different scenarios for the division of ventilation air can be applied, for instance depending on the season or the time. In order to ensure an accurate regulation and limit flow-induced noise as far as possible, the valves are preferably low-resistance valves.

In order to avoid as far as possible the penetration of suction and extraction noises into the different rooms of the building, the dividing unit and/or the collecting unit is preferably manufactured from or lined with a sound-damping material.

A further noise reduction can be achieved when the installation is provided with at least one sound damper placed respectively between the suction device and the dividing device on the one hand and the extraction device and the collecting unit on the other.

An optimum division of ventilation air over the different rooms is obtained when the installation is provided with means connected to the regulating means for the purpose of detecting the ventilation requirement in the different rooms. Ventilation can then take place in demand- driven manner. These detection means can for instance comprise temperature sensors placed in each of the rooms, whereby a temperature-controlled ventilation is possible. It is also possible in addition or instead to envisage the detection means comprising presence sensors placed in each of the rooms, so that only those rooms in which people are actually present are ventilated.

In order to not only optimally control the amount of ventilation air but also the temperature thereof, and to limit as far as possible the energy consumption of the installation, this latter is preferably provided with exchange means for bringing outside air drawn in by the suction device into heat-exchanging contact with used air coming from the rooms. A compact and simple installation is obtained here when the exchange means comprise at least one heat exchanger placed respectively between the suction device and the dividing unit on the one hand and the extraction device and the collecting unit on the other. The invention is now elucidated on the basis of an example, wherein reference is made to the accompanying drawing, in which:

Fig. 1 is a schematic view of the physical embodiment of the most important components of a ventilation installation according to the invention, and

Fig. 2 is a schematic diagram of a building with a number of rooms and the installation of fig. 1.

An installation 1 for ventilating a building 3 with a number of rooms 2A-F comprises according to the invention a suction device 5 placed at a central location 4 of building 3 and a number of ventilation ducts 6 leading from suction device 5 to different rooms 2A-C. When building 3 is a house, central location 4 can for instance be the attic, while rooms 2A-2C receiving the ventilation air V can for instance be the living room and two bedrooms. In addition, ventilation installation 1 comprises a dividing unit 7 placed between suction device 5 and ventilation ducts 6, as well as means 8 for regulating this dividing unit 7 on the basis of the ventilation requirement of each room 2.

Dividing unit 7 takes the form of a box 9 which is provided with an inflow opening 10 connected to suction device 5 and a number of outflow openings 11 connected to ventilation ducts 6. Box 9 can be manufactured from - or lined with - a sound-damping material. Suction device 5 is adapted to maintain a constant pressure in box 9 and in the shown example takes the form of a so-called constant pressure-regulated fan. Regulating means 8 act on these outflow openings 11 in the sense that they comprise controllable valves 12 which are placed in outflow openings 11.

Ventilation installation 1 further comprises an extraction device 13, which is likewise placed at central location 4 and which can be structurally integrated with suction device 5, as will be elucidated hereinbelow. This extraction device 13 is connected to different rooms 2D-F via a number of return ducts 14, wherein a collecting unit 15 is placed between these return ducts 14 and extraction unit 13. Rooms 2D-F from which the air is extracted are for instance the kitchen, the bathroom and the toilet. On the extraction side installation 1 further also has means 16 for

regulating collecting unit 15 on the basis of the ventilation requirement of each room 2.

The construction of collecting unit 15 corresponds to that of dividing unit 7. Collecting unit 15 thus also takes the form of a box 17 with an outflow opening 18 connected to extraction device 13, and a number of inflow openings 19 which are each connected to one of the return ducts 14. Block 17 can further be lined with a sound-damping material once again, or even be manufactured therefrom. Extraction device 13 is again adapted to maintain a constant pressure in box 17 and, as suction device 5, takes the form of a constant pressure-regulated fan. Regulating means 16 act on inflow openings 19 and once again comprise for this purpose controllable valves 20 in these openings. Valves 12 in dividing unit 7 and valves 20 in collecting unit 15 are embodied in the shown example as low- resistance valves which enable a very precise regulation of the flow surface of respectively outflow openings 11 and inflow openings 19. Regulating means 8 on the suction side and regulating means 16 on the extraction side can comprise a shared electronic control unit 21 connected to both valves 12 and valves 20. This electronic control unit 21 is given a programmable form here so that the regulation of valves 12, 20 can be carried out according to different programs, adjusted for instance to the time of day, the season or the use of the building. A house can for instance be ventilated more during the evening and at night, since it can be expected that more people will be at home then than during the day. Conversely, it is possible to opt for a limited ventilation in an office building or a factory outside usual working hours.

The programming of control unit 21 can take place when ventilation installation 1 is installed or taken into use. The program can be loaded onto a data carrier, such as a CD-ROM or a USB stick, which can be read by control unit 21. Interim modification of the programming is also possible. It is even possible to program control unit 21 remotely, for instance by incorporating it in a local network or providing it with a transmitting and receiving module. In order to enable control unit 21 to optimize the regulation it must be provided with the correct data. In the shown example ventilation installation 1 is provided for this purpose with means 22 for detecting the ventilation requirement in the different rooms 2. These detection means 22 can comprise sensors, for instance temperature sensors, hygrometers and/or presence sensors, in each of the rooms 2. The information is hereby demand-driven information.

Finally, installation 1 is also provided with exchange means 23 whereby the outside air F drawn in by suction device 5 can be brought into heat-exchanging contact with used air R coming from rooms 2 before it is discharged to the outside (arrow D) . These exchange means 23 here take the form of a heat exchanger placed between suction device 5 and dividing unit 7 on the one hand and extraction device 13 and collecting unit 15 on the other. The indrawn outside air F can hereby be preheated in winter by the residual heat in used air R, which will be roughly room temperature. Conversely, the indrawn air will be warmer in the summer than room temperature, and will thus be cooled by the used air. As already indicated above, suction device 5 and extraction device 13 in the shown example are structurally integrated into a single casing 24 together with heat exchanger 23.

Sound dampers 25, 26 are here otherwise also placed between this casing 24 and respectively the dividing unit 7 and collecting unit 15 in order to prevent motor noise from suction device 5 and extraction device 13 penetrating into the rooms 2 for ventilating. These sound dampers 26 thus amplify the damping action of respective pressure boxes 9, 17 of dividing unit 7 and collecting unit 15.

With the above described installation 1 it is thus possible to optimally ventilate each of the different rooms 2 in building 3, wherein different parameters can be taken into account, such as the temperature or air humidity in this room, the use of the room and the like. Furthermore, the installation can be installed and set relatively quickly and easily, while the settings can also be readily modified to for instance changing requirements of use and the like.

Although the invention is elucidated above on the basis of an example, it will be apparent that it is not limited thereto, but can be varied and modified in many ways within the scope of the following claims.