FR2938900A1 - Air conditioning device for use in e.g. house, has circuit whose secondary heat exchanger is controlled and arranged in downstream of section and exchanging heat between air and exchanging medium formed by solar sensor - Google Patents

Abstract

The device (14) has a circulating unit (26) for circulating air in an air renewal circuit (16) i.e. ventilator. A main heat exchanger (28) is formed by burying a section of an air inlet conduit (18) of the circuit in a terrestrial basement (30) at a depth. The section is made of a heat conductive material, so that temperature of the air attains an underground temperature. The circuit has a secondary heat exchanger (34) controlled and arranged in a downstream of the section and exchanging heat between the air and an exchanging medium formed by a solar sensor.

Description

The invention relates to an air conditioning device at a set temperature for at least one part of a building. The invention relates more particularly to an air conditioning device at a temperature close to a set temperature for at least one part of a building, the device comprising: - an air renewal circuit which comprises at least one upstream inlet of the air outside the building at an outside temperature and at least one downstream outlet orifice inside the room of the air at an outlet temperature close to the set temperature; Means for circulating the air in the renewal circuit, such as a fan; a main heat exchanger which is formed by at least one section of an air intake pipe of the renewal circuit which is buried in the earth's subsoil at a depth at which there is a substantially constant underground temperature , the buried section of the pipe being made of a heat conducting material so that the temperature of the circulating air approaches the underground temperature. It is generally advisable to maintain the temperature inside inhabited buildings, such as houses or buildings, at a set temperature around 20 ° C, especially for the comfort of the inhabitants. Moreover, when the air stagnates in the rooms of the building, there is a risk of mold growth or that the air becomes stale and harmful to health. It is therefore known to equip buildings with a ventilation system, such as a controlled mechanical ventilation system 2 or "VMC", to constantly renew the building air at the rate of several volumes of air from the house per day. However, the renewal air is sucked outside the building. This air very often has a temperature different from the set temperature. Thus, in winter, outdoor air is generally much colder than the set temperature, while in summer outdoor air is warmer than the set temperature. Air conditioning devices of the type previously described which are sometimes called "Canadian wells" are already known. Such a device makes it possible to renew the air in the rooms of a building with outside air by making it possible to bring the temperature of the outside air closer to the set temperature by using geothermal energy. This energy has the advantage of being completely non-polluting and not producing greenhouse gases. Generally, in winter, the outside air temperature is much lower than the set temperature, for example below 0 ° C. The outside air can be warmed by a few degrees, for example at 1 ° C, before being pumped back into the rooms of the building. The energy required to heat the air introduced into the house up to the set temperature is thus reduced compared to an air renewal device which delivers air directly to the outside temperature in the rooms of the building. . Conversely, in summer, when the outside temperature is higher than the set temperature, the Canadian well is able to cool the air so as to approach the set temperature. Such a Canadian well can thus save energy when using an air conditioner. However, even when using a Canadian well, it is still necessary to use polluting or greenhouse gas sources to heat building air in winter, such as electric heating, heating, and heating. heating oil, or to cool the building air in summer, such as an electric air conditioner. To solve this problem by decreasing or even completely eliminating the use of polluting energies to maintain the air temperature inside the building at a set temperature, the present invention proposes an air conditioning device. of the type described above, characterized in that the renewal circuit comprises at least one controlled secondary heat exchanger which is arranged downstream of the buried section and which exchanges heat between the circulating air and at least one exchange medium . According to other characteristics of the invention: the secondary heat exchanger exchanges heat with the exchange medium via a closed circuit of heat transfer fluid; The exchange medium is capable of forming a natural source of heat; the heat of the exchange medium is captured and stored in a heat storage means which is arranged to supply heat to the coolant of the heat transport circuit; The storage means is formed by an adiabatic enclosure which is filled with a storage fluid with high thermal inertia; - The storage fluid forms the heat transfer fluid of the heat transport circuit; The exchange medium is capable of forming a natural heat sink which is able to absorb heat from the circulating air when it is hotter than the set temperature; the exchange medium is formed by a solar collector; 4 - the exchange medium is formed by the terrestrial subsoil; - A section of the heat transport circuit is buried in the earth's subsoil so as to allow the exchange of heat between the coolant and the earth's subsoil; the exchange medium is formed by a water table; the fluid constituting the water table forms the heat transfer fluid of the heat transfer fluid circuit; a portion of the heat transport circuit is immersed in a water table so as to allow heat exchange between the heat transfer fluid and the terrestrial subsoil; - The heat transport circuit comprises a controlled means, such as a pump, for circulating the coolant in the circuit according to the outside temperature of the air and the set temperature; The conditioning device comprises an electronic control unit for the heat-transfer fluid circulating means, in particular as a function of the outside temperature, the set temperature, the temperature of the air at the outlet of the buried section, and the the temperature of the air at the outlet 20 of the renewal circuit, so that the temperature of the air at the outlet of the renewal circuit is as close as possible to the set temperature. Other features and advantages will become apparent on reading the detailed description which follows, for the understanding of which reference will be made to the appended drawings in which: FIG. 1 is a schematic view showing a building equipped with a device packaging device according to a first embodiment of the invention using a geothermal sensor; - Figure 2 is a view similar to that of Figure 1 which shows a second embodiment of the invention using a water table; - Figure 3 is a view similar to that of Figure 1 which shows a third embodiment of the invention using a solar collector; FIG. 4 is a view similar to that of FIG. 1, which shows a fourth embodiment of the invention using a solar collector and a heat storage enclosure; - Figure 5 is a view similar to that of Figure 1 which shows a fifth embodiment of the invention io in combination with a geothermal sensor and a solar collector. In the remainder of the description, elements having identical, analogous or similar functions will be designated by the same reference number. In the remainder of the description, a flow direction of the air or fluids oriented from upstream to downstream will be adopted. In addition, it will be understood that the term "heat" is used in the thermodynamic sense. Thus, the heating of the air by a warmer source is by heat exchange from the heat source to the air, resulting in a positive amount of heat for the air, while the Cooling of the air by a colder source is done by heat exchange from the air to the cold source, resulting in a supply of a negative amount of heat for the air. FIG. 1 shows a building 10 that has several closed dwelling rooms 12, for example a house or a building containing apartments or offices. The building 10 is equipped with a device 14 for air conditioning at a temperature close to a set temperature "Tc". The air conditioner 14 performs at least two functions.

The first function is to constantly renew the air inside the rooms 12 of the building 10 at a flow rate that is generally regulated by national standards, for example due to a renewal of the total air volume of the building at less once an hour or five times an hour. The second function of the air conditioning device 14 is to approach the temperature of the air "Tsor" introduced into the building 10 as much as possible of the set temperature "Tc" relative to the outside temperature "Text". The setpoint temperature "Tc" is, for example, of the order of 20 ° C. The air conditioning device 14 comprises an air renewal circuit 16 which comprises an air supply line 18 which has an upstream inlet 20 for entering the air outside the building 10, and at least one air distribution line 22 which is connected by its upstream end to the air supply line 18 and which has at least one downstream outlet 24 air outlet inside the rooms 12. The driving The air-conditioning device 14 also has at least one means 26 for circulating the air in the renewal circuit 16 since the air intake device 18 is arranged at least partly outside the building 10. its upstream inlet orifice 20 which draws the outside air to its downstream outlet orifice 24 which delivers the air inside the rooms 12. The circulation means 26 is here formed by a fan 26 which is interposed between the air supply line 18 and the air distribution duct 18 22. The air conditioner 14 also has a main heat exchanger which is formed by a buried section 28 of the air supply line 18 which is buried in the earthen subsoil 30. Referring to FIG. 1, the buried section 28 is formed by the part of the air supply pipe 18 which is parallel to the surface of the ground 32. The buried section 28 is here buried at a constant depth, for example two meters below the surface of the ground 32. Subsequently, the buried section 28 will be called "Canadian well" 28.

The Canadian Well 28 is here specifically buried directly in a trench that has been dug into the ground and has been completely filled with the excavated earth to form the trench. In general, the Canadian well 28 is buried at a depth at which there is a substantially constant underground temperature "Tsol". By "constant", it will be understood that the temperature varies with a very small amplitude compared to daily or even seasonal temperature changes. For example, at two meters depth, the underground temperature "Tsol" is 13 ° C in winter and 17 ° C in summer, ie a maximum annual amplitude of 4 ° C while the maximum annual temperature amplitude outdoor "Text" may exceed 20 ° C. To allow heat exchange between the terrestrial subsoil 30 and the air circulating in the Canadian well 28, the Canadian well 28 is made of a heat conducting material so that the temperature of the air flowing through the Inside the Canadian Well 28 approaches the underground temperature "Tsol". The Canadian well 28 is for example made of polyethylene. With this main heat exchanger, the outside air, which has an outside temperature "Text" before being sucked into the air renewal circuit 16, has, at its exit from the Canadian well 28, an intermediate temperature. "Tint" approaching the "Tsol" basement temperature relative to the "Text" outdoor temperature. According to a first embodiment of the invention shown in FIG. 1, the renewal circuit 16 comprises a controlled secondary heat exchanger 34 which is arranged 8 downstream of the Canadian well 28. The secondary heat exchanger 34 is more particularly interposed in the renewal circuit 16 between the fan 26 and the distribution pipe 22.

The secondary heat exchanger 34 is intended to exchange heat between the air circulating in the renewal circuit 16 and at least one exchange medium. The exchange medium is very advantageously capable of forming a natural source of heat when it is a matter of heating the temperature of the air circulating in the renewal circuit 16, that is to say when the intermediate temperature "Tint" is below the set temperature "Tc". By "natural source of heat", it will be understood that it is a source that produces or stores heat that is not produced directly or indirectly by burning a fuel, or by electricity from the electrical distribution network. The exchange medium is also capable of forming a natural heat sink which is able to absorb heat from the air circulating in the renewal circuit 16 when the intermediate temperature "Tint" is higher than the set temperature. Tc ". The exchange medium is here formed by the terrestrial subsoil 30. The secondary heat exchanger 34 exchanges heat with the exchange medium 30 via a closed heat transfer fluid circuit 36. heat transfer fluid is for example a mixture of water and antifreeze, or a thermal oil, or brine, or any other heat transfer fluid compound. A section 37 of the coolant circuit 36 is buried in the terrestrial subsoil 30 so as to allow the exchange of heat between the coolant and the terrestrial subsoil 30. The heat exchange is carried out in one direction or in one direction. the other as a function of the intermediate temperature "Tint" of the air circulating in the renewal circuit 16 at the outlet of the Canadian well 28. Subsequently, the buried section of the heat transport circuit 36 will be called "geothermal sensor 37".

To allow the exchange of heat between the coolant and the subsoil, the conduit forming the geothermal sensor 37 is made of a heat conducting material such as polyethylene. The duct forming the geothermal sensor 37 has a serpentine shape having a plurality of horizontally spaced, parallel straight sections buried at the same depth as the Canadian well 28. For reasons of clarity, the geothermal sensor 37 has been shown at a depth different from that of the Canadian well 28 in FIG. 1. The heat transport circuit 36 comprises a means controlled to circulate the heat transfer fluid in the heat transfer circuit 36 as a function of the intermediate temperature "Tint" of the air and the temperature of the setpoint "Tc". The circulation means is a pump (not shown in Figure 1). The device 14 also comprises an electronic unit (not shown) for controlling the circulating heat transfer fluid pump so that the "Tsor" temperature of the air coming out of the renewal circuit 16 is as close as possible to the temperature of the setpoint "Tc". The conditioning device 14 is controlled by the electronic unit, in particular as a function of the outside temperature "Text", the set temperature "Tc", and the temperature of the air at the outlet of the Canadian well "Tint". and the temperature "Tsor" of the air at the outlet of the renewal circuit 30 16, so that the temperature of the air at the outlet of the renewal circuit "Tsor" is as close as possible to the set temperature "Tc". The design of the heat transport circuit 36, and in particular of the geothermal sensor 37, depends on the one hand on the climate to which the building 10 is exposed, and in particular on the maximum outside temperatures "Tmax" and minimum "Tmin", and on the other hand volume of air contained in the building 10 and the flow "Dm" of air renewal. The following example is given to illustrate the dimensioning of the conditioning device 14. In this example it will be assumed that the data are as follows: io - the maximum summer outdoor temperature "Tmax" is 32 ° C; - the minimum outside temperature in winter "Tmin" is -7 ° C; the set temperature "Tc" is 20 ° C; 15 - the temperature of the subsoil "Tsol" in winter is 13 ° C to two meters deep; - the temperature of the basement "Tsol" in summer is 16 ° C at two meters depth. Furthermore, the air change rate and the volume of the building 20 may be of a building volume per hour or five building volumes per hour. For example, the building has an interior volume of 300 m3. The renewal of the air can therefore be done at a rate of 300 m3 / h or 1500 m3 / h. By taking again the notations already used, the thermal power dissipated in winter by the renewal of the air without conditioning or on the contrary the thermal power brought in summer by the renewal of the air without conditioning are calculated according to the following formula, the power thermal value being expressed in Watts: Qv = 0.34 • Dm • (Text ûTc) For the extreme temperature conditions given as examples, the heat loss at the outside temperature 2938900 It minimum "Tmin" for a renewal of a volume per hour is -2754 W, while it is equal to -13770 W for a renewal of five volumes per hour. In summer, the external heat input at the maximum outdoor temperature "Tmax" is 714 W for a volume renewal per hour or 3570 W for a five volume renewal per hour. Furthermore, the thermal power likely to be provided by the Canadian well 28 and the geothermal sensor io 37 depends in particular on the nature of the subsoil 30. The recoverable power according to the nature of the subsoil 30 is indicated in FIG. watts per square meter in Table 1 below. Dry sandy soil 10 to 15 W / m2 Wet sandy soil 15 to 20 W / m2 Dry clay soil 20 to 25 W / m2 Wet clay soil 25 to 30 W / m2 Aquifer soil 30 to 35 W / m2 Table 1 The length and width The diameter of the buried pipe section 15 forming the Canadian well 28 is calculated so that, under the conditions of minimum outside temperature "Tmin", the intermediate temperature "Tint" of the air circulating in the renewal circuit 16 has, at the exit from Canadian well 28, a value of around 1 ° C. Likewise, the dimensions of the geothermal sensor 37 are calculated so that the air outlet "Tsor" temperature of the renewal circuit 16 can approach even more the set temperature "Tc". For example, an outlet temperature of the air renewal circuit 16 which is close to 12 ° C. at the coldest of the winter, that is to say for the minimum outside temperature "Tmin" or 21 ° C during the warmest summer, that is for the maximum outside temperature "Tmax". The following table is an example of data that makes it possible to size the geothermal sensor 37 as a function of the diameter of the duct employed, the horizontal spacing reserved between two parallel rectilinear sections of the coil and the heat recovery recoverable by the ground. Diameter Spacing Power in W / m2 as a function of the pipe in meters of the soil Power in W / m of pipe 15 20 25 30 35 16x20 0.30 to 0.35 3.33 5 6.66 8.33 10 11, 66 19x25 0.45 to 0.50 4.55 6.80 9.09 11.36 13.63 15.90 26x32 0.60 to 0.75 6.02 9.03 12.04 15.06 18.07 21,08 Table 2 In this example the Canadian well 28 and the geothermal sensor are sized to obtain the results given in the following Table 3: Canadian well Geothermal sensor Dm (m3 / h) Text Tint Qvl (W) Tint Tsor Qv2 (W) WINTER 300 -7 ° C 1 ° C 816 1 ° C 11 ° C 1020 1500 4080 5100 SUM 300 32 ° C 23 ° C -918 23 ° C 18 ° C -510 1500 -4590 -2550 Table 3 Thus in winter, when the outside air is colder than the set temperature "Tc", the outside air is sucked into the inlet port 20 by the fan 26. Then, it passes through the Canadian well. 28. During this passage, the circulating air absorbs the heat of the subsoil 30 by conduction through the wall of the can well. 28. The air heats locally along the wall while remaining cold in the middle of the duct section. This thermal imbalance 13 causes a convection movement of the circulating air which makes it possible to homogenize the temperature of the air throughout the section of the Canadian well 28. At the exit of the Canadian well 28, the temperature of the air is raised to reach its intermediate temperature "Tint" which is for example equal to 1 ° C for a minimum outside temperature "Tmin". The control unit controls the start-up of the heating circuit pump 36 so as to allow the air circulating in the renewal circuit 16 to be heated again to the intermediate temperature "Tint" when the intermediate temperature "Tint" is reached. less than the set temperature "Tc". Thus, by circulating through the coil formed by the geothermal sensor 37, the heat transfer fluid captures the heat present in the basement. The coolant thus "charged" in heat flows to the secondary heat exchanger 34. The heat carried by the heat transfer fluid is thus transferred to the air circulating in the secondary heat exchanger 34. The coolant thus " The heat discharged thereafter flows to the geothermal sensor 37 to reiterate a heat transport cycle. The air heats up to reach the outlet temperature "Tsor" which here has a value of 12 ° C.

Thus, the renewal air is introduced at a temperature "Tsor" of 12 ° C in the rooms 12 of the building 10. The device (not shown) for heating the building only has to provide the necessary heating power to raise the air temperature from 12 ° C to the set temperature "Tc" of 20 ° C. The heat required to heat the air from -7 ° C up to 12 ° C has indeed been provided free and non-polluting by the basement 30. 14 Similarly, in summer, when the outside air is warmer than the set temperature "Tc", the outside air is sucked into the inlet port 20 by the fan 26. Then, it passes through the Canadian well 28. During its passage, the basement 30 absorbs heat from the air by conduction through the wall of the Canadian well 28. The air cools locally along the wall while remaining warmer in the middle of the duct section. This thermal imbalance causes a convection movement of the circulating air which makes it possible to homogenize the temperature of the air throughout the section of the Canadian well 28. At the exit of the Canadian well 28, the temperature of the air is lowered to reach its intermediate temperature "Tint", which is for example equal to 23 ° C for a maximum outside temperature "Tmax". The control unit controls the start of the heat transport pump 36 so as to further cool the air circulating in the renewal circuit 16 when the intermediate temperature "Tint" is greater than the set temperature "Tc ". Thus, the heat transfer fluid captures the heat present in the air circulating in the secondary heat exchanger 34. The heat transfer fluid is thus "loaded" with heat in excess of the air.

This heat is then transferred by conduction to the subsoil when the coolant circulates through the coil formed by the geothermal sensor 37. The heat transfer fluid thus "discharged" from its heat is then redirected to the secondary heat exchanger 34 in order to reiterate a heat transport cycle. The air thus cools to reach the outlet temperature "Tsor" which here has a value of 18 ° C. Thus, it is not necessary to equip the building with an expensive and polluting air conditioning device. The energy required to cool the air from 32 ° C to 18 ° C has indeed been provided free of charge and non-polluting by the subsoil 30.

A second embodiment of the invention is shown in Figure 2. This second embodiment is similar to the first embodiment described above. Only the differences between these two embodiments will therefore be described later.

In this second embodiment, the exchange medium of the secondary heat exchanger 34 is formed by a water table 40. The heat transfer fluid is here formed by the water constituting the water table which is pumped by the heat transport pump. 36 to the secondary heat exchanger 34, then the water is discharged to the water table 40 after heat exchange, in one direction or the other, with the air flowing in the secondary heat exchanger 34. The operation of the conditioning device 14 is similar to that described in the first embodiment. In a variant not shown, the coolant is separated from the water table 40, that is to say that the coolant circuit 36 is not open on the water table 40. The heat transfer fluid circuit 36 then comprises a section which is immersed in the water table so as to allow the exchange of heat between the coolant and the water table. A third embodiment is shown in Figure 3. This third embodiment is similar to the first embodiment. Only the differences between these two embodiments will therefore be described later. In this third embodiment, the exchange medium of the secondary heat exchanger 34 is formed by a solar collector 42. In this embodiment, the exchange medium forms a natural source of heat that is not not likely to form a heat sink. Thus, the secondary heat exchanger 34 is used only when the intermediate temperature "Tint" is lower than the set temperature "Tc", for example in winter.

The solar collector 42 is arranged at a place exposed to sunlight, advantageously during the whole of the day. The solar collector is here arranged on the roof of the building. The solar collector 42 is interposed in the coolant circuit 36 so as to heat the coolant.

As for the first embodiment, the circulation of the heat transfer fluid 36 is carried out by a pump controlled by the electronic control unit. The heat transfer fluid circuit 36 operates in the manner described in the first embodiment for transmitting the heat of the solar radiation captured by the solar collector 42 to the air circulating in the air renewal circuit 16. This third mode It is possible to operate only when the solar radiation is sufficient to supply heat to the coolant.

A fourth embodiment of the invention is shown in FIG. 4. This fourth embodiment is similar to the third embodiment. However, the heat captured by the solar collector 42 is here stored in a means 44 for storing heat. The heat thus stored is then used to heat the air via the heat transfer circuit 36. The storage means is formed by an adiabatic enclosure 44 which is filled with a high thermal inertia fluid. The storage enclosure 44 is here buried under the ground 17 so as not to encumber the building 10 and so that the earth participates in the thermal insulation of the storage enclosure 44. In this embodiment, a second closed circuit of heat transfer fluid 46, distinct from the first heat transfer circuit 36, is provided for transmitting the heat of the solar radiation to the storage enclosure 44. For this purpose, the solar collector 42 is interposed in the second heat transfer circuit 46, and a section 48 of the second heat transport circuit 46 passes through the storage enclosure 44 so as to transmit by conduction the heat transported by the heat transfer fluid to the storage fluid. The second heat transfer fluid circuit 46 comprises a pump 50 independent of the pump of the first heat transfer circuit 36. The first heat transfer circuit 36 is arranged to transmit the heat stored in the storage chamber 44 to a first heat exchanger. Secondary heat 34. In the example shown in FIG. 4, the storage fluid forms the coolant of the first coolant circuit 36. In other words, the storage enclosure 44 is interposed in the first coolant circuit 36 of the whereby the heated storage fluid can be pumped to the first secondary heat exchanger 34 to heat the air.

This embodiment thus makes it possible to heat the incoming air by means of solar energy permanently, including at night. In addition, such an arrangement also makes it possible to store the strong solar radiation received in summer for use in winter. This embodiment can also be combined with a water heater 52 for the hot water supply of the building. Thus, a single solar collector 42 is common to the water heating device, or water heater, and to the conditioning device 14.

Furthermore, the second heat-transfer circuit 46 may be associated with a second secondary heat exchanger 54 which is interposed in the renewal circuit 16. The second secondary heat exchanger 54 is here arranged just before the outlet orifice 24 of the secondary heat exchanger 54. 'air. The second heat transfer circuit 46 here comprises a bypass line 56 which is connected to a pipe arranged downstream of the solar collector 42 via a three-way valve. Thus, when the fluid contained in the storage chamber 44 is not sufficiently hot, it is possible to heat the air circulating in the renewal line 16 as indicated in the third embodiment via this method. secondary heat exchanger 54. According to a variant of this fourth embodiment and analogously to FIG. 4, the heat contained in the subsoil 30 can be stored in an adiabatic enclosure 44 identical to that described in the fourth embodiment embodiment of the invention. The difference with the fourth embodiment is that there is no second heat transport circuit. Indeed, the storage chamber 20 is arranged directly in the basement. Its walls consist of a heat conductive material that heats the storage fluid to the temperature of the subsoil. Of course, it is possible to combine the different embodiments together by interposing a plurality of secondary heat exchangers in series in the renewal circuit 16 to obtain an even more efficient air conditioning device 14. Thus, FIG. 5 shows a combination between the first embodiment and the third embodiment of the invention. The conditioning device 14 thus comprises a first secondary heat exchanger 34 thermally coupled to a geothermal sensor 37 via a first heat transfer circuit 36 and a second secondary heat exchanger 54 which is thermally coupled to a solar collector 42 via a second heat transfer circuit. 46. Each heat transport circuit 34, 46 is then equipped with an associated pump which can be controlled independently of one another by the electronic control unit so that the air outlet temperature "Tsor" is the as close as possible to the set temperature "Tc". This arrangement makes it possible, in particular in winter, to successively heat the air circulating in the renewal circuit 16 by three main and secondary heat exchangers arranged in series in the renewal circuit 16. The air conditioning device 14 made According to the teachings of the invention, it is thus possible to regulate the temperature of the air inside a building 10 by ensuring the renewal of air and by using very little energy of polluting origin. Only the energy needed to operate the pumps and the fan is likely to be polluting.

Claims (15)

REVENDICATIONS1. Air conditioning device (14) at a temperature close to a set temperature (Tc) for at least one room (12) of a building (10), the device (14) comprising: - a renewal circuit of air (16) having at least one upstream inlet (20) for entering the outside air to the building (10) at an outside temperature (Text) and at least one downstream outlet (24) at the outlet the interior of the room (12) of the air at an outlet temperature (Tsor) close to the set temperature (Tc); means (26) for circulating the air in the renewal circuit (16), such as a fan; a main heat exchanger (28) which is formed by at least one section (28) of an air supply line (18) of the renewal circuit (16) which is buried in the earth's subsoil (30) to a depth at which there is a substantially constant underground temperature (Tsol), the buried section (28) of the pipe being made of a heat conducting material so that the temperature of the circulating air approaches underground temperature (Tsol); characterized in that the renewal circuit (16) comprises at least one controlled secondary heat exchanger (34, 54) which is arranged downstream of the buried section (28) and which exchanges heat between the circulating air and the minus an exchange medium (30, 40, 42). 2. Device (14) according to the preceding claim, characterized in that the secondary heat exchanger (34, 54) exchanges heat with the exchange medium (30, 40, 42, 44) 30 via a closed coolant circuit (36, 46). 3. Device (14) according to any one of the preceding claims, characterized in that the medium 21 of exchange (30, 40, 42) is capable of forming a natural source of heat. 4. Device (14) according to the preceding claim, characterized in that the heat of the exchange medium is captured and stored in a means (44) for storing heat which is arranged to provide heat to the coolant of the heat transport circuit (36). 5. Device (14) according to the preceding claim, characterized in that the storage means is formed by an adiabatic enclosure (44) which is filled with a storage medium with high thermal inertia. 6. Device (14) according to the preceding claim, characterized in that the storage fluid forms the heat transfer fluid of the heat transport circuit (36). 7. Device (14) according to any one of the preceding claims, characterized in that the exchange medium (30, 40) is capable of forming a natural heat sink which is adapted to absorb heat from the air circulating when it is warmer than the set temperature (Tc). 8. Device (14) according to any one of claims 1 to 5, characterized in that the exchange medium is formed by a solar collector (42). 9. Device (14) according to any one of claims 1 to 7, characterized in that the exchange medium 25 is formed by the terrestrial subsoil (30). 10. Device (14) according to the preceding claim taken in combination with any one of claims 1 to 3, characterized in that a section (37) of the coolant circuit (36) is buried in the earth's subsoil (30). ) so as to allow the exchange of heat between the coolant and the terrestrial subsoil (30). 22 11. Device (14) according to any one of claims 1 to 7, characterized in that the exchange medium is formed by a water table (40). 12. Device (14) according to the preceding claim, characterized in that the fluid constituting the water table (40) forms the heat transfer fluid of the coolant circuit (36). 13. Device (14) according to claim 10 taken in combination with any one of claims 1 to 3, characterized in that a section (37) of the coolant circuit (36) is immersed in a water table (40) so as to allow the exchange of heat between the heat transfer fluid and the terrestrial subsoil (30). 14. Device (14) according to any one of the preceding claims, characterized in that the coolant circuit (36, 46) comprises a controlled means, such as a pump, for circulating the coolant in the circuit (36). , 46) as a function of the outside temperature of the air (Text) and the set temperature (Tc). 20 15. Device (14) according to the preceding claim, characterized in that it comprises an electronic control unit of the coolant circulation means in particular depending on the outside temperature (Text), the set temperature (Tc), the temperature of the air at the outlet of the buried section (Tint), and the temperature of the air at the outlet of the renewal circuit (Tsor), so that the temperature of the air at the outlet of the Renewal circuit (Tsor) is as close as possible to the set temperature (Tc).