IE20100802A1

IE20100802A1 - Thermodynamic water-heater

Info

Publication number: IE20100802A1
Application number: IE20100802A
Authority: IE
Inventors: Moktar Bouagila; Gerard Carette; Lionel Palandre
Original assignee: Muller & Cie Ets M
Priority date: 2009-12-24
Filing date: 2010-12-23
Publication date: 2011-07-06
Also published as: IT1403204B1; FR2954815A1; FR2954815B1; ES2398547A1; PT105444B; GB2476567B; ES2398547B1; ITBO20100760A1; PT105444A; GB2476567A; GB201021508D0

Abstract

The present invention refers to a water-heater (1) provided with a heat pump (3) comprising a circuit through which flows a refrigerant, said heat pump comprising notably an evaporator (4), said evaporator being a heat exchanger air/refrigerant, said water-heater being characterised in that it is provided with a conduit (8) comprising an external tube (10) and an internal tube (11), at least one part of the internal tube being contained in the external tube, said two tubes defining two parallels air circulation circuits (16, 17), each one of said circuits opening into a compartment (13, 15), a communication between said compartments being formed by the evaporator. The present invention also refers to a heating installation comprising such a water-heater. <Figure 1>

Description

LODGED Ther nodynamic water-heater The present invention refers to a thermodynamic water-heater, said water-heater being notably intended for the heating of domestic water. The 5 present invention also refers to a heating installation equipped with such a water-heater.

In the field of the domestic heating, search is currently undertaken to reduce the energy expenditure. The thermodynamic water-heaters present notably a much better energetic efficiency than the electric water-heaters.

A thermodynamic water-heater is a water-heater provided with a heat pump as a means of heating. The principle of a heat pump is to take calories from a heat source, for example from the air, in order to transfer them to the water in the water-heater.

In a conventional way, a heat pump comprises a circuit through which flows a refrigerant. A refrigerant is a substance able to absorb and restore heat, according to changes of state liquid /gas or gas/liquid. This circuit of refrigerant extends notably through two heat exchangers: - a condenser, which enables the heat transfer from the fluid to the water to be heated; - an evaporator, which enables the fluid to take calories from a heat source, for example the air outside the water-heater.

In a dwelling, it is known to place the thermodynamic water-heater in an unheated room, such as a cellar or a garage. Thus, the heat taken by the evaporator of the water-heater does not have direct consequences on the heating needs for the dwelling.

However, if the cellar or the garage is placed beside heated rooms, the latter undergo a heat loss indirectly. The total energy balance of the heating installation of the dwelling is then decreased.

In addition, the dwellings such as apartments have seldom an unheated room, appropriate to the installation of a thermodynamic water-heater.

IE 1 00 S 02 To solve this problem, it is known to install conduits extending through an external wail of a dwelling, in order to take heat from the air outside the dwelling and/or to reject the cooled air outside the dwelling.

The heat source being the outside air, the operation of the heat pump 5 does not have any impact on the heating needs for the dwelling. On the other hand, the installation of such conduits requires the carrying out of several perforations through an external wall of the dwelling, which complicates the installation of the thermodynamic water-heater.

The present invention makes it possible to simplify the installation of 10 such a thermodynamic water-heater, while allowing the heat pump to use a heat source outside the building receiving said water-heater. indeed, an object of this invention is a water-heater provided with a heat pump comprising a circuit through which flows a refrigerant, said heat pump comprising notably an evaporator, said evaporator being a heat exchanger air/refrigerant, said water-heater being characterized in that it is provided with a conduit comprising an external tube and an internal tube, at least one part of the internal tube being contained in the external tube, said two tubes defining two air circuits, each one of said circuits opening into a compartment, a communication between said compartments being formed by the evaporator.

Thus, the air entering by one of both circuits flows through the evaporator before going out again through the other circuit. It is thus possible to take the air outside a building, as well as to reject the cooled air outside, thanks to a single conduit. Such a device simplifies the installation of the water-heater and facilitates the installation of thermodynamic water-heaters in residences such as apartments.

According to a preferred embodiment of the invention, the internal tube is made out of a thermally insulating material, so as to minimize heat exchange between the entering air and the outgoing air.

Thus, the air taken outside the building brings a maximum of calories to the evaporator. ΙΕ 100 802 According to a preferred embodiment of the invention, the water-heater comprises a ventilator allowing a circulation of air, towards the evaporator, through a first air circuit between the internal tube and the external tube, in this manner, the air enters through an external circuit of the conduit. It flows then through the evaporator and goes out through an internal circuit, formed by the interior of the tube of lower diameter.

According to a preferred embodiment of the invention, at the end of the conduit opposite the evaporator, a section of the internal tube of the conduit is lower than the annular section of the space between the two tubes. More precisely, the section of the air output circuit is lower than the section of the input circuit. This embodiment reduces the risks of recycling the cooled air in the input circuit.

In addition, according to a preferred embodiment of the invention, at the end of the conduit opposite the evaporator, the external tube is set back from the internal tube of the conduit. Indeed, a difference in the tube lengths also reduces the risks of recycling the cooled air in the input circuit.

According to a preferred embodiment of the invention, the compartment into which opens the air input circuit contains apparatuses the operation of which produces heat. These apparatuses can be a compressor of the heat pump and/or a motor actuating the ventilator. Thus, the air entering said compartment recovers the heat released by said apparatuses, before it flows through the evaporator.

The invention also aims at a heating installation, notably for a building, comprising a water-heater such as previously described.

According to a preferred embodiment of the invention, the water-heater comprises a tank located inside a building and the end of the conduit opposite the evaporator is located outside said building.

According to a preferred embodiment of the invention, an end of the internal tube, near the evaporator, is located outside the external tube.

The invention also aims at a method for mounting an instaliation according to the invention, including the connection of the external tube to an IE 1 00 8 02 existing duct of the building and the installation of a part of the internal tube into said existing duct.

The invention wili be better understood by reading the following description and by examining the accompanying figures. Those are given as an indication and by no means as a restriction of the invention. The figures show: - Figure 1: a schematic sectional view of a water-heater according to a first embodiment ofthe invention; - Figure 2: a schematic view of an element of the water-heater 10 represented in figure 1; - Figure 3: a detailed view of a water-heater according to a second embodiment ofthe invention; - Figure 4: a detailed view of a water-heater according to a third embodiment of the invention.

The figure 1 represents a schematic view of a water-heater according to an embodiment of the invention. The water-heater 1 comprises notably a tank 2, connected to a domestic water circuit (not represented).

The water-heater 1 is provided with a heat pump system 3 intended to heat the water in the tank 2. The system 3 comprises notably a circuit (not represented) through which flows a refrigerant. Said circuit extends notably through an evaporator 4, a compressor 5, a condenser which heats the water in the tank 2 and a pressure reducer.

The evaporator 4 is a heat exchanger air/refrigerant. In order to increase the thermal transfer between the air and the walls of the evaporator 4, the system is equipped with a ventilator 6, which generates a forced convection of air through the evaporator 4.

The water-heater belongs to a heating installation of a dwelling 7. The majority of the elements of the water-heater 1, notably the tank 2, are installed inside the dwelling 7.

JE 1 0 0 8 0 2 However, the principal heat source of the heat pump system 3 is the air outside the dwelling 7. Thus, the operation of said system 3 does not increase the heating needs for said dwelling.

The outside air is put in contact with the evaporator 4 via a conduit 8, which extends through an external wall 9 of the dwelling 7.

The conduit 8 comprises two concentric tubes. For simplification reasons, it is considered in the following description that these two tubes have a circular section. However, other sectional forms are possible.

The conduit 8 comprises a first external tube 10, inside which a second 10 internal tube 11 is located, which has a diameter inferior to that of the tube . The diameters of the tubes {10, 11) respectively, are such that there is a gap 16 between said tubes.

An end 12 of the external tube 10 opens into a first compartment 13 of the heat pump system 3. An end 14 of the internal tube 11 opens into a second compartment 15 of the system 3.

The evaporator 4 is located between the compartments 13 and 15, so that the air can fiow from one compartment to the other while flowing through said evaporator. Preferentially, the external tube 10 and the internal tube 11 of the conduit 8 are the only communications of the compartments 13 and 15 with the outside. Preferentially, the single direct communication between the compartments 13 and 15 is formed by the evaporator 4.

The ventilator 6 is placed in the second compartment 15, at the end 14 of the internal tube 11. Preferentially, its direction of rotation is such that the air flowing through the tube goes from the evaporator 4 towards the outside of the dwelling 7, The depression thus generated inside the first compartment 13 causes the aspiration of the outside air into the gap 16 between the external tube 10 and the internal tube 11.

The tubes 10 and 11 thus form two parallel air circuits (16,17), in which the air flows in opposite direction. The circuit 17 is formed by the interior of the internal tube 11.

IE 1 00 302 When the ventilator 6 is working, the air surrounding the dwelling 7 is thus aspired into the circuit 16, located between the tubes 10 and 11. The air arrives in the first compartment 13. In a preferential way, this compartment contains one or several apparatuses likely to release heat, such as the compressor 5 and/or a motor actuating the ventilator 6.

The air flows then through the evaporator 4 where the air heat is transferred to the refrigerant. It flows then into the second compartment 15 where the ventilator 6 is located. After a passage in the circuit 17 formed by the interior of the internal tube 11, the air is finally rejected outside the dwelling 7. In the figure 1, the air path is represented by arrows.

The figure 2 represents a schematic sectional view of the end of the conduit opposite the evaporator 4, according to the embodiment represented in figure 1, More precisely, the figure 2 represents a part of the conduit 8 extending through the wall 9 and opening outside the dwelling 7.

The end 18 of the external tube 10 and the end 19 of the internal tube 11, opposite the evaporator, are thus located outside the building 7, As described previously, the outside air is aspired into the circuit 16, located between the tubes 13 and 15. After the transfer of its heat to the evaporator 4, it is rejected by the circuit 17 located inside the internal tube 11.

The air circulating in the circuit 16 is thus generally at a higher temperature than the air circulating in the circuit 17. For example, there can be a difference in temperature of approximately 5°C between the two circuits.

Consequently, the internal tube 11 is preferentially made so as to minimize heat exchange between the circuits 16 and 17. In a preferential way, the internal tube 11 consists of a material having a iow thermal conductance, for example a plastic material such as PVC. In the same way, preferentially, the tube 11 has a relatively great thickness, for example of at least 3 mm.

The external tube 10 can also be made out of plastic material.

In order to avoid a return of air into the conduit, the end 18 of the external tube 10 is preferentially set back from the end 19 of the internal f£ 1 00 8 02 tube. Thus, the air is rejected by the internal tube 11 at a certain distance from the input 18 of the external tube 10. The cooled air is thus not aspired again by the conduit 8.

In a preferential way, a distance 20 between the ends 18 and 19 is 5 equal to at least 50% of a diameter 21 of the internal tube 11.

In addition, in a preferential way, a section ofthe tube 11 at its end 19 is lower than an annular section ofthe circuit 16 at its end 18.

The air being colder inside the tube 11 than around said tube, moisture is likely to condense onto an external wall ofthe tube 11.

In a preferential way, in a heating installation, the conduit 8 is installed so as to avoid the accumulation of moisture in one of its points. More precisely, in a vertical axis, one avoids laying the conduit 8 in a U shape, with a part of minimal altitude which would be likely to collect condensation. It is preferable to lay the conduit with a slope of constant sign between its two ends. It is also possible to lay the conduit in a reversed-U shape, with a part of maximum altitude.

In the embodiment represented in figure 1, the conduit 8 comprises a substantially vertical part near the evaporator 4 and a substantially horizontal part which extends through the wall 9. It is also possible to tilt the part which extends through the wall 9, in order to support the flow of moisture.

In the example represented in figure 1, the heat pump system 3 is placed above the tank 2 and the conduit is located above the system 3. If one chooses to tilt the conduit 8 towards the water-heater, it is possible to provide means for recovering and evacuating condensation close to the end 14 ofthe tube 11.

According to another embodiment, the conduit 8 is tilted outwards, while maintaining a slope of constant sign over all its length. This disposition is possible for example when the heat pump system is placed lower than the tank 2, the conduit 8 itself being located lower than the system 3.

The figure 3 represents a detailed view of another embodiment of the invention. One can see a water-heater 101 equipping a dwelling 107. The IE 100802 water-heater is provided with a conduit 108, said conduit being represented in a sectional view. The conduit 108 comprises an external tube 110 which opens into a duct 109 ofthe dwelling 107. In the case in point, the duct 109 is a flue, substantially vertical and opening onto the roof of the dwelling 107.

The conduit 108 comprises moreover an internal tube 111, a part of which is contained in the external tube 110 and another part is contained in the duct 109. An end of the part 122 opens onto the roof of the dwelling 107, such as the duct 109.

As in the example represented in figure 1, the air goes out of the circuit 117 formed by the interior of the internal tube 111. A part of the air input circuit 116 is formed by the gap between the part 122 of the tube 111 and the duct 109.

This embodiment makes it possible to take advantage of existing ducts, such as chimneys, at the time ofthe installation of water-heaters according to the invention in dwellings.

The figure 4 represents a detailed view of another embodiment of the invention. It is an alternative ofthe embodiment represented in figure 1.

It can be seen a water-heater 201 equipping a building 207. The waterheater is provided with a conduit 208, said conduit being represented in a sectional view.

The conduit 208 comprises a first tube 210 and a second tube 211. A part 223 of the tube 210 extends though a wall 209 of the building 207, through an opening in said wall. A part ofthe tube 211 is contained in the part 223 ofthe tube 210.

In addition, inside the building 207, an end 224 of the tube 211 and an end 225 of the tube 210 are connected to a body of the water-heater 201, near the evaporator equipping the heat pump of said water-heater. The end 224 of the tube 211 is placed outside the tube 210. More precisely, a wall of the tube 210 comprises an opening 226, through which extends the tube 211.

The opening 226 is located between the end 225 and the part 223 of the tube 210, therefore inside the building 207.

IE 1 00 Θ 02 Thus, a part of the tube 211 is located inside the tube 210, which makes it possible to bore only one hole in the wall 209 to install the conduit 208. In addition, another part of the tube 221, notably its end 224, is located outside the tube 210. Said end is thus more accessible than that of the internal tube 11 represented in figure 1. This embodiment of the invention facilitates the independent connection of each tube of the conduit 208 to the heat pump system of the water-heater 201.

In order to facilitate the connection of the tubes 210 and 211 to the body of the water-heater, the parts of said tubes close to the ends 224 and 225 can be made out of a material such as a flexible plastic material.

Claims

1. Water-heater (1) provided with a heat pump (3) comprising a circuit through which flows a refrigerant, said heat pump comprising notably an evaporator (4), said 5 evaporator being an heat exchanger air/refrigerant, Said water-heater being characterized in that it is provided with a conduit (8) comprising an external tube (10) and an internal tube (11), at least one part of the internal tube being contained in the external tube, said two tubes defining two air circuits (16, 17), each one of said circuits opening into a compartment (13, 15), a 10 communication between said compartments being formed by the evaporator.

2. Water-heater according to claim 1, wherein the internal tube (11) is made out of a thermally insulating material. 15

3. Water-heater according to claim 1 or claim 2, comprising a ventilator (6) allowing a circulation of air, towards the evaporator, in a first air circuit between both tubes (10,11).

4. Water-heater according to any one of the preceding claims, wherein at one 20 end (18,19) of the conduit opposite the evaporator, a section of the internal tube (11) of the conduit is iower than the annular section of a gap (16) between the internal tube and the externa! tube.

5. Water-heater according to any one of the preceding claims, wherein at one 25 end (18,19) of the conduit opposite the evaporator, the external tube (10) is set back from the internal tube (11).

6. Water-heater according to any one of the claims 3 to 5, wherein a compressor (5) of the heat pump and/or a motor actuating the ventilator (6) are located in a 30 compartment (13) into which opens the first air circuit.

7. Heating installation comprising a water-heater according to any one of the preceding claims, characterized in that the water-heater comprises a tank (2) located ΙΕ ή 00 802 inside a building (7) and in that one end (18, 19) of the conduit opposite the evaporator is located outside said building.

8. Installation according to claim 7, wherein, in a vertical direction, the conduit is 5 laid with a slope of constant sign.

9. Installation according to any one of the claims 7 to 8, wherein one end (224) of the Internal tube (211), located near the evaporator, is outside the external tube (210).

10. Method for mounting an installation according to any one of the claims 7 to 9, including the connection of the external tube (10) to an existing duct (109) of the building (107) and the installation of a part of the internal tube (111) in said existing duct.