[0001] The present invention relates to a ventilating unit for use on the inner side of
an outside wall of a building, which ventilating unit comprises a passage for passing
outside air through the outside wall, control means for regulating the amount of outside
air that is admitted through the passage, and a control unit for controlling said
control means on the basis of the pressure difference between the inside and the outside
of the building.
[0002] Such a ventilating unit is known from practice, and it functions to provide a natural
and comfortable ventilation of buildings, and in particular of office buildings. A
constant ventilation flow, which reduces any nuisance caused by draught, can be obtained
by means of said control unit and the control means, which consist of a ventilation
grille. Since the unit is built into an outside wall of the building, a complicated
system of tubes is not needed, which makes it possible to keep costs low and reduce
the risk of sick building syndrome, which is caused by long, contaminated ventilation
ducts, in which germs can accumulate and develop.
[0003] The object of the invention is to provide a ventilating unit which enhances comfort
even more and which is furthermore capable of effecting an energy saving.
[0004] In order to accomplish that objective the ventilating unit according to the invention
is characterized in that said ventilating unit is provided with a passageway, which
extends between the passage in the outside wall and the bottom side of a heating element
when the ventilating unit is installed, whilst the control means are mounted in said
passageway.
[0005] Since the inflowing air is heated before it enters the room to be ventilated, any
nuisance caused by draught that can be perceived is reduced even more. The direct
heating of the air by means of the heating element makes it possible to achieve an
energy saving.
[0006] Preferably the ventilating unit is provided with a temperature sensor which is connected
to the control unit, which sensor may be mounted near the upper side of the heating
element, for example, where the ventilating air can flow past the sensor.
[0007] In this manner the ventilating unit can be controlled not only on the basis of the
pressure difference between the outer side and the inner side of the outside wall,
but also on the basis of the temperature. It is possible to arrange thereby that the
temperature of the outflowing air above the heating element must not fall below a
preset value, which value is preferably adjustable, between 12°C and 20°C, for example.
If the temperature falls below the preset value, the amount of outside air that is
admitted will be reduced until the preset temperature is reached again.
[0008] Furthermore it is possible to use the outside temperature as a measure for the control
precision. When the outside temperature is low, a high control precision may be selected,
whilst the control precision will be lower when the outside temperature is high. This
aspect makes it possible to reduce the amount of adjusting movements of the control
means, which saves energy and prolongs the life of the moving components of the control
means. Another possibility is to make this a "sliding" influence, wherein control
can be made dependent of the number of movements of the control means in a preceding
period.
[0009] The control means preferably comprise a valve which is mounted in the passageway,
and which is capable of shutting off said passageway or releasing it partially or
completely. It is advantageous if the valve can also be manually controlled. When
the valve is closed, the control system will be disabled. On the other hand it is
possible to put the valve in the open position, but in that case it is preferred to
provide a frost protection device, which closes the control means if the exit temperature
falls below 3°C, for example, in order to protect the heating element, which generally
works with water, against freezing.
[0010] The invention will be explained in more detail hereafter with reference to the drawing,
which is a very diagrammatic representation of an embodiment of the invention.
[0011] Fig. 1 is a ground plan of a house which is fitted with a number of ventilating units
according to the present invention.
[0012] Fig. 2 is a larger-scale front view of a ventilating unit according to the invention,
which is installed between an outside wall and a heating element.
[0013] Fig. 3 is a side view of the unit of Fig. 2.
[0014] Fig. 4 is a view which corresponds with Fig. 3, without the outside wall, however,
wherein the air flow through the ventilating unit and the heating element is shown.
[0015] Fig. 5 is a larger-scale perspective view of a separate ventilating unit.
[0016] Fig. 1 is a ground plan of a house, in which the present invention is used. The house
has two outside walls 1, on which heating elements 2 are mounted in the various rooms.
Said heating elements may be independent heating elements, but generally they will
form part of a central heating system, and in that case the heating elements 2 will
consist of radiators, in which water heated by a boiler provides the supply of heat.
A passage 3 has been formed in the outside wall 1 at the location of each heating
element 2, which passage functions to pass outside air through the outside wall 1
into the interior of the house for the purpose of ventilating the house. Each passage
3 gives way to a ventilating unit 4, which is disposed between outside wall 1 and
heating element 2 in this case. The exhaust of air takes place via exhaust channels
12, which may or may not be fitted with an exhaust fan.
[0017] As is shown in particular in Figs. 2, 3 and 4, ventilating unit 4 is provided with
a passageway 5, which extends between passage 3 in outside wall 1 and the bottom side
of the associated heating element 2 when the ventilating unit 4 is installed. Heating
element 2 is internally provided with a vertical passage 6, so that rising air can
be heated from two side over a long distance before it enters the room of the house
or other type of building.
[0018] In order to achieve a comfortable regulation of the amount of outside air that is
admitted through passage 3, ventilating unit 4 is fitted with a (preferably electronic)
control unit 7 (Fig. 5), to which control means, in this case in the form of a valve
8, are connected. The valve may be capable of stepless operation, or it may close
or open the passageway 5 of ventilating unit 4 partially or entirely in a number of
steps. Preferably the control unit is set for controlling valve 8 on the basis of
the pressure difference between the inner side and the outer side of outside wall
1 of the house, in order to obtain a constant flow of outside air when pressure differences
vary.
[0019] In this embodiment passageway 5 of ventilating unit 4 comprises an upward portion
5' and a downward portion 5'', and slide valve or rotary valve 8 is provided near
the transition between the two portions 5' and 5''. The valve is driven by means of
an electric motor 9, which is connected to control unit 7, or by another drive unit
for adjusting the valve 8.
[0020] Ventilating unit 4 is fitted with a sensor 10, which is capable of measuring the
pressure difference between the two sides of the outside wall, on the basis of which
pressure difference valve 8 is controlled so as to obtain a desired air flow, for
example a more constant or less constant air flow.
[0021] As it is important that the temperature of the air which enters via heating element
2 is sufficiently high, it is preferred to have the control of valve 8 also take place
on the basis of the temperature of the inflowing air. Ventilating unit 4 is to that
end provided with a temperature sensor 11, which is mounted near the place where the
heated air exits heating element 2, in this case near the upper side of heating element
2. This temperature sensor 11 makes it possible to ensure that the temperature of
the outflowing air will not fall below a preset value, whereby said preset value may
for example be a temperature selected from a possible range of 12 - 20°C, for example
15 to 16°C. Usually no draught problems occur with exit temperatures within this range.
[0022] The power for the electric motor 9 and the control unit 7 may be taken from the existing
electricity grid, but it is also possible to use a separate direct current power supply,
a battery or a solar cell, for this purpose. If more than one ventilating unit 4 is
used, said units may be coupled, and if said units are used in combination with a
central heating system, they may also be coupled to the boiler, so that the temperature
control of the central heating system takes place in cooperation with the control
of the heating unit. All this depends on the particular use. In newly built houses
or in office buildings more central facilities can be provided that in existing houses,
where one or more ventilating units according to the invention are added later on,
for example when carrying out a renovation project. Of course several variations and
additions are possible on the basis of the present principle. Thus, manual influencing
will preferably be possible, in order to provide a possibility of interfering with
the control system according to the circumstances. Furthermore a filter for filtering
the inflowing air may be incorporated in ventilating unit 4, said filtering may take
place electrostatically, for example, but also mechanically or otherwise. The generation
of a ventilating flow may take place in a natural manner, but on the other hand it
is possible to build in exhaust fans so as to effect mechanical ventilation. The ventilating
unit may be fitted with means which ensure that the valve will be closed if the supply
voltage is cut off, this in order to prevent an undesirable inflow of air and freezing
of the water in heating element 2. Said means may comprise a capacitor, for example.
[0023] From the foregoing it will be apparent that the invention provides a ventilating
unit which is capable of providing comfortable and energy-saving ventilation of houses
and other buildings, without large investments being required, whilst the ventilating
unit can also be built into existing buildings without any difficulty.
[0024] The invention is not limited to the embodiment described above and illustrated in
the drawing, which can be varied in several ways within the framework of the invention.
1. A ventilating unit for use on the inner side of an outside wall (1) of a building,
which ventilating unit comprises a passage (3) for passing outside air through the
outside wall, control means (8) for regulating the amount of outside air that is admitted
through the passage, and a control unit (7) for controlling said control means on
the basis of the pressure difference between the inner side and the outer side of
the outside wall, characterized in that said ventilating unit (4) is provided with a passageway (5), which extends between
the passage (3) in the outside wall and the bottom side of a heating element (2) when
the ventilating unit is installed, whilst the control means (8) are mounted in said
passageway (5).
2. A ventilating unit provided with a temperature sensor (11), which is connected to
the control unit (7).
3. A ventilating unit according to claim 2, wherein said temperature sensor (11) can
be mounted near the upper side of the heating element (2), where the ventilating air
can flow past the sensor.
4. A ventilating unit according to any one of the preceding claims, wherein said control
means (8) are mounted within the ends of the passageway (5), and wherein said control
means (8) preferably comprise a sensor (10) for measuring the amount of air flowing
through.
5. A ventilating unit according to claim 4, wherein said passageway (5) comprises a first,
upwardly extending portion (5'), seen from the outer side of the outside wall (1),
and a second, downwardly extending portion (5''), and wherein said control means (8)
are preferably provided at the transition between said two portions (5', 5'').
6. A ventilating unit according to any one of the preceding claims, wherein said control
means (8) comprise a valve, which is preferably also manually adjustable, whilst a
sensor (10) that may be provided will be mounted before the valve, seen in the direction
of flow.
7. A ventilating unit according to any one of the preceding claims, wherein the heating
element (2) is internally provided with a vertically passage (6), to the bottom side
of which the passageway (5) can be connected.
8. A ventilating unit according to any one of the preceding claims, wherein the control
precision of the control unit (7) depends on the outside temperature.
9. A ventilating unit according to any one of the claims 2 - 8, which is provided with
a frost protection device, which is arranged for closing the control means (8) if
the temperature sensor (11) measures a temperature which is lower than a preset minimum
value.
10. A ventilating unit according to any one of the preceding claims, wherein the control
unit (7) can be connected to a thermostat of the heating element (2), preferably to
the thermostat of a central heating system of which the heating element forms part.