Combined thermodynamic installation for a building

Abstract

Installation (1) comprising: - a refrigerant circuit (2) - an outdoor unit (4) - an indoor unit (6) - a storage tank (8) - a control unit configured to activate an auxiliary heating system (16) for the storage tank (8) when the refrigerant is circulating, the indoor unit valves (11; 12) are open, one of the storage tank valves (13; 4) is closed, and the temperature Tc measured by a probe (15) is less than or equal to a threshold temperature Ts determined to prevent migration (M) of the refrigerant. Figure for the abbreviation: Figure 1

Description

Title of the invention: Combined thermodynamic installation for a building. Technical field

[0001] The present invention relates to building design. In particular, the invention relates to a combined thermodynamic installation for a building and a method for controlling such an installation. Technological background

[0002] In a building, to produce domestic hot water on the one hand and heating or air conditioning on the other, it is known to use a combined system.

[0003] Such a system combines, for example, a refrigerant circuit to which a reversible heat compressor, an indoor unit for heating or air conditioning and a water storage tank are connected.

[0004] Refrigerants are generally polluting, flammable, and harmful. In view of these aspects, it is advantageous to limit the quantity of refrigerant in combined systems.

[0005] However, in these limited refrigerant systems, due to the small quantity of refrigerant, significant amounts of refrigerant sometimes migrate into the storage tank. In particular, some of the refrigerant in the tank's heat exchanger can transition into a liquid phase. This excessive refrigerant migration, relative to the total quantity of refrigerant, leads to malfunctions in the system and may even damage it.

[0006] There is therefore a need for a combined thermodynamic installation that limits the risk of fluid migration towards the heat exchanger of the tank. Summary of the invention

[0007] The present invention meets this need by means of, according to one of its aspects, a combined thermodynamic installation for a building, in particular for heating water for heating and producing temperature-controlled air within that building, comprising: - a refrigerant circuit comprising a compressor system configured to circulate a refrigerant within the refrigerant circuit in a first direction of circulation in a heating mode and in a second direction of circulation in an air conditioning mode; - an outdoor unit comprising a first heat exchanger in fluid communication with the refrigerant circuit and configured to carry out a heat exchange between outside air and the refrigerant; - an indoor unit, for example of an air conditioning system, comprising a second heat exchanger in fluid communication with the refrigerant circuit and configured to carry out a heat exchange between the refrigerant and an indoor heating fluid, for example from the ambient air to the building; - a domestic hot water storage tank comprising a third heat exchanger in fluid communication with the refrigerant circuit and configured to perform a heat exchange between the refrigerant and domestic hot water present in a tank of the tank to heat this domestic hot water, - an indoor unit valve system comprising a first indoor unit valve and a second indoor unit valve respectively positioned upstream and downstream of the second heat exchanger, in the first direction of refrigerant flow, to regulate the refrigerant flow through the second heat exchanger, - a tank valve system comprising a first tank valve and a second tank valve respectively positioned upstream and downstream of the third heat exchanger, in the first direction of refrigerant flow, to regulate the flow of refrigerant through the third exchanger, the tank comprising a water temperature probe in the tank at the level of the third heat exchanger, the tank further comprising an auxiliary water heating system in the tank, also called an additional heating system; - a control unit communicating information with the compressor system, the auxiliary heating system, the indoor unit valve system and the tank valve system, the control unit being configured to turn on the tank's auxiliary heating system when the compressor system is circulating the refrigerant, the first and second indoor unit valves are open, one of the first and second tank valves is closed, the other of the first and second tank valves is notably open, and the temperature Te measured by the temperature probe is less than or equal to a threshold temperature Ts, the threshold temperature Ts being determined so as to prevent migration of the refrigerant from the second heat exchanger to the third heat exchanger.

[0008] Thanks to the control of the auxiliary heating system by the control unit, the installation according to the invention prevents refrigerant migration to the third heat exchanger when the latter is not in operation. This ensures proper operation of the installation and limits the amount of refrigerant required.

[0009] The circuit may include a refrigerant pressure sensor near the first tank valve, the second tank valve, or the third heat exchanger, for example between the second tank valve and the second indoor unit valve, the control unit being configured to determine said threshold temperature Ts as a function of the refrigerant pressure measured by the pressure sensor, particularly when the installation is in air conditioning mode.

[0010] The control unit can be configured to determine the evaporation temperature Te of the refrigerant present in the tank from the measurement of the refrigerant pressure measured by the pressure sensor so as to allow the determination of the threshold temperature Ts.

[0011] The control unit can be configured to determine a threshold temperature Ts higher than the evaporation temperature Te.

[0012] The indoor unit may include a refrigerant temperature sensor. The control unit may be configured to determine the threshold temperature Ts of the refrigerant in the tank based on the refrigerant temperature measured by the temperature sensor in the indoor unit, particularly when the system is in heating mode.

[0013] The tank of the balloon may include an upper part and a lower part, the third heat exchanger being positioned in the lower part.

[0014] The tank of the balloon can extend along a longitudinal axis, in particular vertically.

[0015] The tank of the water heater can have a domestic hot water storage volume of between 50 1 and 500 1.

[0016] The temperature probe can be positioned at a height measured along the longitudinal axis between 20% and 30% of the height of the tank measured along the longitudinal axis.

[0017] The temperature probe can be positioned at a height measured along the longitudinal axis between 10% and 50% of the height of the third heat exchanger measured along the longitudinal axis.

[0018] By "open valve" we mean that the valve is fully open or partially open.

[0019] The first and second indoor unit valves and the first and second tank valves may be solenoid valves and / or solenoid valves and / or electronic expansion valves.

[0020] The first indoor unit valve and / or the second indoor unit valve and / or the first tank valve and / or the second tank valve can be positioned in at least three different positions, in particular to allow regulation of the refrigerant flow rate. Said at least three different positions include a closed valve position, a fully open valve position and at least one partially open valve position.

[0021] When one of the valves used can be positioned in at least three different positions, in particular when said valve is an electronic regulator, by "open valve" means that the valve is in the fully open position of the valve or in said at least one partially open position of the valve.

[0022] The auxiliary heating system can extend from the bottom of the tank.

[0023] The auxiliary system can have a heating power between 100 W and 3000 W.

[0024] The auxiliary heating system can be electric.

[0025] The refrigerant can be chosen from the group consisting of the R-134a (Tetrafluoroethane), R-410A (Difluoromethane and Pentafluoroethane Mixture), R-32 (Difluoromethane), R-22 (Chlorodifluoromethane), R-290 (Propane), R-600a (Isobutane), R-1234yf (Tetrafluoropropene), R-744 (Carbon Dioxide), and a mixture of these.

[0026] The installation may include one or more additional indoor units, each comprising a heat exchanger in fluid communication with the refrigerant circuit and configured to carry out heat exchange between the refrigerant and an indoor heating fluid.

[0027] The indoor unit may be a wall unit, in particular fixed to an interior wall, generally used in residential air conditioning systems.

[0028] The indoor unit may be a console unit, in particular installed at the bottom of a wall, similar to a radiator, suitable for residential and commercial spaces.

[0029] The indoor unit may be a ducted unit, in particular installed in a false ceiling or a technical space, allowing discreet distribution of air via ducts.

[0030] The indoor unit can be a cassette unit, in particular mounted in a suspended ceiling, ideal for offices and commercial spaces, distributing air in several directions.

[0031] The indoor unit may be a ceiling unit, in particular fixed directly to the ceiling, used in spaces where wall installation is not possible.

[0032] The invention further relates, in combination with the foregoing, to a method for controlling an installation as defined above, in which the first and second indoor unit valves are open and one of the first and second tank valves is closed, the other of the first and second tank valves being in particular open, the method comprising the following steps: a) circulate the refrigerant in the refrigerant circuit using the compressor system, the refrigerant circulating in the second heat exchanger of the indoor unit; b) measure the temperature Te in the tank of the balloon at the level of the third heat exchanger using the water temperature probe; c) if the temperature Te is less than or equal to the threshold temperature Ts, turn on the auxiliary heating system so as to heat the water in the tank at the level of the third heat exchanger (9) to a higher temperature to prevent condensation of the refrigerant in the third heat exchanger.

[0033] The method may include a step of measuring the temperature of the refrigerant at the indoor unit using the refrigerant temperature probe at the indoor unit and determining the threshold temperature Ts from said temperature measurement, in particular when the installation is in heating mode.

[0034] The method may include a step of measuring the pressure of the refrigerant using the pressure sensor and determining the threshold temperature Ts from said pressure measurement, particularly when the installation is in air conditioning mode.

[0035] The process may include a step of determining the evaporation temperature Te of the refrigerant present in the third heat exchanger of the tank from the measurement of the refrigerant pressure measured by the pressure sensor, the threshold temperature Ts being determined to be greater than the evaporation temperature Te.

[0036] After step c), when the temperature measured by the temperature probe is greater than a predetermined cutoff temperature Tf, the auxiliary heating system can be stopped. Brief description of the figures

[0037] The following description, with reference to the accompanying drawings, given by way of non-limiting examples, will clearly explain what the invention consists of and how it can be implemented. In the accompanying figures:

[0038] [Fig. 1] illustrates a combined thermodynamic installation for a building according to the invention,

[0039] [Fig.2] shows a schematic view of the domestic hot water storage tank of the installation of [Fig.1],

[0040] [Fig.3] shows the installation of [Fig.1] in air conditioning mode with potential refrigerant migration,

[0041] [Fig.4] shows the installation of [Fig.1] in heating mode with potential refrigerant migration, and

[0042] [Fig.5] illustrates a variant of a combined dynamic installation for a building according to the invention. Description of method(s) of implementation

[0043] In the following description, identical elements or elements with identical functions bear the same reference numeral. For the sake of brevity, they are not described opposite each figure; only the differences between the embodiments are described.

[0044] In the figures, the actual proportions have not always been respected, for the sake of clarity.

[0045] Figures 1 and 2 illustrate an example of a combined thermodynamic installation 1 according to the invention.

[0046] The combined thermodynamic installation 1 includes a refrigerant circuit 2. This circuit 2 is equipped with a compressor system 3 designed to circulate the refrigerant in one direction for heating ([Fig.4]) and in the other direction for air conditioning ([Fig.3]).

[0047] In a manner known per se, the compressor system 3 includes in particular a compressor 31 and a four-way valve 32 for selecting the direction of circulation of the refrigerant.

[0048] The circuit 2 is connected to an outdoor unit 4, for example located outside the building, which contains a first heat exchanger 5. This heat exchanger 5 allows heat transfer between the outside air and the refrigerant.

[0049] Installation 1 also includes an indoor unit 6, which may be part of an air conditioning system. Installation 1 may include a plurality of indoor units without departing from the scope of the invention.

[0050] The indoor unit 6 can be a wall unit, a console unit, a ducted unit, a cassette unit or a ceiling unit.

[0051] The indoor unit 6 contains a second heat exchanger 7. This second heat exchanger 7 is connected to the circuit 2 and allows heat exchange between the refrigerant and an indoor heating fluid, such as the ambient air of the building.

[0052] Installation 1 includes for the indoor unit 6, or each indoor unit if installation 1 includes several, an indoor unit valve system comprising a first indoor unit valve 11 and a second indoor unit valve 12, placed respectively upstream and downstream of the second heat exchanger 7 in a direction of refrigerant flow.

[0053] These valves 11 and 12 regulate the circulation of the refrigerant through the second heat exchanger 7.

[0054] The installation 1 also includes a domestic hot water storage tank 8 comprising a tank 10 in which extends a third heat exchanger 9, as illustrated in particular in [Fig.2].

[0055] Tank 10 has for example a capacity of 200 l, the invention not being limited to a specific capacity.

[0056] This third heat exchanger 9 is connected to circuit 2 and allows heat exchange between the refrigerant and the domestic hot water present in the tank 10 to heat this water.

[0057] As with the indoor unit 6, the installation 1 includes a tank valve system comprising a first tank valve 13 and a second tank valve 14, placed respectively upstream and downstream of the third heat exchanger 9 in a direction of refrigerant flow, in order to regulate the flow of refrigerant through the third heat exchanger 9.

[0058] The first indoor unit valve 11 and the first balloon valve 13 are electronic expansion valves, in this example EEV expansion valves (in English "electronic expansion valves").

[0059] The second indoor unit valve 12 and the second tank valve 14 are solenoid valves and / or solenoid valves.

[0060] Since the objective of the tank 8 is to store hot water, the refrigerant can only circulate in the third heat exchanger when the refrigerant circulates in circuit 2 in the direction for heating.

[0061] The tank 10 extends along a longitudinal axis X, which is for example vertical, and comprises an upper part 20 and a lower part 21. The third heat exchanger 9 is positioned in the lower part 21 so as to heat the cold layers of the water present in the tank 10.

[0062] The tank 8 is also equipped with a temperature probe 15 to measure the temperature of the water in the tank 10 at the level of the third heat exchanger 9.

[0063] The temperature probe 15 is positioned at a height H measured along the longitudinal axis X between 20% and 30% of the height Hc of the tank 10 measured along the longitudinal axis X. This position corresponds approximately to a median position of the height He measured along the longitudinal axis X of the third heat exchanger 9.

[0064] In addition, the tank 8 includes an auxiliary heating system 16 for heating the water in the tank 10 extending from a bottom 23 of the tank 10. The auxiliary system 16 may be of the electric type.

[0065] The installation 1 may include a pressure sensor 17 of the refrigerant in the circuit 2 near the third heat exchanger 9, for example between the second tank valve 14 and the second indoor unit valve 12.

[0066] The indoor unit 4 may also include a temperature probe 30 of the refrigerant at the level of the indoor unit 4.

[0067] Installation 1 further includes a control unit (not shown) whose operation is described later in the description.

[0068] Figures 3 and 4 illustrate two different operating modes of the installation 1 of [Fig.1] for which a risk of refrigerant migration M exists.

[0069] In [Fig.3], the installation 1 is in air conditioning mode. The first indoor unit valve 11 and the second indoor unit valve 12 are open, to allow the production of cold air by the indoor unit 6, while the first tank valve 13 is closed and the second tank valve 14 is open, so as not to draw heat from the water present in the tank 10.

[0070] Preferably, in all operating modes of the installation 1, the first tank valve 13 and the second tank valve 14 are never closed at the same time so as not to isolate the part of the circuit 2 at the tank 8. Indeed, this allows for a uniform fluid pressure, which avoids excessive stress on the first tank valve 13 and the second tank valve 14.

[0071] This operating mode may result in a potential migration M of the refrigerant from the second heat exchanger 7 to the third heat exchanger 9 in the event of condensation of some of the refrigerant at that point. This may occur, in particular, when the water temperature in the lower part 21 of the tank 10 is low.

[0072] In [Fig.4], the installation 1 is in heating mode. The first indoor unit valve 11 and the second indoor unit valve 12 are open, to allow the production of hot air by the indoor unit 6, while the first tank valve 13 is open and the second tank valve 14 is closed, for example when the production of hot water is not desired.

[0073] This can also lead to a potential migration M of the refrigerant from the second heat exchanger 7 to the third heat exchanger 9. This can be the case in particular when the temperature of the water in the lower part 21 of the tank 10 is low.

[0074] The installation control unit is in communication with the compressor system 3, the auxiliary heating system 16, the indoor unit valve system, the tank valve system, the pressure sensor 17, the temperature probe 15 and the temperature probe 30 of the refrigerant at the indoor unit 4.

[0075] To prevent this migration, the pilot unit is configured to act according to the process described below when the first and second indoor unit valves 11, 12 are open and one of the first and second tank valves 13, 14 is closed, while the other of the first and second balloon valves 13, 14 is open.

[0076] The method of controlling the installation 1 first includes circulating the refrigerant in the circuit 2 using the compressor system 3, the refrigerant circulating in the second heat exchanger 7 of the indoor unit 6.

[0077] Next, the temperature Te is measured in the tank 10 of the balloon 8 at the level of the third heat exchanger 9 using the water temperature probe 15.

[0078] If the temperature Te is less than or equal to a threshold temperature Ts, the control unit turns on the auxiliary heating system 16 to heat the water in the tank 10 at the level of the third heat exchanger 9 to a higher temperature to prevent condensation of the refrigerant in the third heat exchanger 9. Condensation being prevented, the migration of fluid M is avoided.

[0079] For determining the threshold temperature Ts, the method includes a step of measuring the refrigerant pressure using the pressure sensor 17, particularly when the system 1 is in air conditioning mode. The evaporation temperature Te of the refrigerant present in the third heat exchanger 9 of the tank 8 is determined from the refrigerant pressure measured by the pressure sensor 17, and the threshold temperature Ts is determined to be higher than the evaporation temperature Te.

[0080] Alternatively, the determination of the threshold temperature Ts includes a step of measuring the temperature of the refrigerant at the indoor unit 4 using the temperature probe 30 of the refrigerant at the indoor unit 4, in particular when the installation 1 is in heating mode.

[0081] After the heating stage, when the temperature measured by the temperature probe 15 is greater than a predetermined cut-off temperature Tf, the auxiliary heating system 16 is stopped.

[0082] The cutoff temperature Tf is greater than the threshold temperature Ts.

[0083] Figure 5 illustrates a variant of the installation 1 according to the invention. In this variant, the first tank valve 13 is connected directly to the compressor 31 and not directly to the four-way valve 32 as in installation 1 of Figure 1. The control operated by the control unit remains identical.

[0084] The invention has several advantages, including the ability to efficiently regulate the temperature of domestic hot water and ambient air in a building, while preventing undesirable migration of the refrigerant between heat exchangers.

Claims

1. Demands Combined thermodynamic installation (1) for a building, in particular for heating water and producing temperature-controlled air within that building, comprising: - a refrigerant circuit (2) including a compressor system (3) configured to circulate a refrigerant within the refrigerant circuit (2) in a first direction of circulation in a heating mode and in a second direction of circulation in an air conditioning mode; - an outdoor unit (4) comprising a first heat exchanger (5) in fluid communication with the refrigerant circuit (2) and configured to carry out a heat exchange between outside air and the refrigerant; - an indoor unit (6), for example of an air conditioning system, comprising a second heat exchanger (7) in fluid communication with the refrigerant circuit (2) and configured to carry out a heat exchange between the refrigerant and an indoor heating fluid, for example of ambient air in the building; - a domestic hot water storage tank (8) comprising a third heat exchanger (9) in fluid communication with the refrigerant circuit (2) and configured to perform a heat exchange between the refrigerant and domestic hot water present in a tank (10) of the tank (8) to heat this domestic hot water, - an indoor unit valve system comprising a first indoor unit valve (11) and a second indoor unit valve (12) respectively positioned upstream and downstream of the second heat exchanger (7), in the first direction of refrigerant flow, to regulate the refrigerant flow through the second heat exchanger (7), - a tank valve system comprising a first tank valve (13) and a second tank valve (14) respectively positioned upstream and downstream of the third heat exchanger (9), in the first direction of refrigerant flow, to regulate the refrigerant flow through the third heat exchanger (9), the tank (8) including a temperature probe (15) of the water in the tank (10) at the level of the third heat exchanger (9), the tank (8) further including an auxiliary heating system (16) of the water in the tank (10); - a control unit in information communication with the compressor system (3), the auxiliary heating system (16), the indoor unit valve system and the tank valve system, the control unit being configured to turn on the auxiliary heating system (16) of the tank (8) when the compressor system (3) is circulating the refrigerant, when the first and second indoor unit valves (11; 12) are open, when one of the first and second tank valves (13;14) is closed, and that the temperature Te measured by the temperature probe (15) is less than or equal to a threshold temperature Ts, the threshold temperature Ts being determined so as to prevent a migration (M) of the refrigerant from the second heat exchanger (7) to the third heat exchanger (9).;

2. Installation (1) according to claim 1, wherein the circuit (2) includes a refrigerant pressure sensor (17) in the vicinity of the first tank valve (13), the second tank valve (14), or the third heat exchanger (9), the control unit being configured to determine said threshold temperature Ts as a function of the refrigerant pressure measured by the pressure sensor (17).

3. Installation (1) according to the preceding claim, wherein the control unit is configured to determine the evaporation temperature Te of the refrigerant present in the tank (8) from the measurement of the refrigerant pressure measured by the pressure sensor (17) so as to allow the determination of the threshold temperature Ts.

4. Installation (1) according to the preceding claim, the control unit being configured to determine a threshold temperature Ts greater than the evaporation temperature Te.

5. Installation (1) according to any one of the preceding claims, wherein the indoor unit (4) includes a refrigerant temperature sensor (30) at the indoor unit (4), and the control unit can be configured to determine the threshold temperature Ts of the refrigerant present in the tank (8) from the measurement of the temperature of the refrigerant measured by the temperature probe (30) of the fluid at the level of the indoor unit (4).

6. Installation (1) according to any one of the preceding claims, wherein the tank (10) of the vessel (8) comprises an upper part (20) and a lower part (21), the third heat exchanger (9) being positioned in the lower part (21).

7. Installation (1) according to any one of the preceding claims, wherein the tank (10) of the balloon (8) extends along a longitudinal axis (X), the temperature probe (15) being positioned at a height (H) measured along the longitudinal axis (X) between 10% and 50% of the height (He) of the third heat exchanger (9) measured along the longitudinal axis (X).

8. Installation (1) according to any one of the preceding claims, wherein the first and second indoor unit valves (11; 12) and the first and second tank valves (13; 14) are solenoid valves and / or solenoid valves and / or electronic expansion valves.

9. Installation (1) according to any one of the preceding claims, wherein the auxiliary heating system (16) extends from a bottom (23) of the tank (10).

10. Installation (1) according to any one of the preceding claims, wherein the auxiliary heating system (16) is electric.

11. A method for controlling an installation (1) according to any one of the preceding claims, wherein the first and second indoor unit valves (11; 12) are open and one of the first and second tank valves (13; 14) is closed, the method comprising the following steps: a) circulating the refrigerant in the refrigerant circuit (2) using the compressor system (3), the refrigerant circulating in the second heat exchanger (7) of the indoor unit (6); b) measuring the temperature Te in the tank (10) of the tank (8) at the third heat exchanger (9) using the water temperature probe (15); c) if the temperature Te is less than or equal to the threshold temperature Ts, switching on the auxiliary heating system (16) so as to heat the water in the tank (10) at the level of the third heat exchanger (9) to a higher temperature to prevent condensation of the refrigerant in the third heat exchanger (9).

12. A method according to the preceding claim, the installation (1) being according to any one of the preceding claims in combination with claim 2, comprising a step of measuring the pressure of the refrigerant fluid using the pressure sensor (17) and determining the threshold temperature Ts from said pressure measurement.

13. A method according to the preceding claim, comprising a step of determining the evaporation temperature Te of the refrigerant present in the third heat exchanger (9) of the tank (8) from the measurement of the refrigerant pressure measured by the pressure sensor (17), the threshold temperature Ts being determined to be greater than the evaporation temperature Te.

14. A method according to claim 11, the installation (1) being according to any one of the preceding claims in combination with claim 5, comprising a step of measuring the temperature of the refrigerant at the indoor unit (4) using the temperature probe (30) of the refrigerant at the indoor unit (4) and determining the threshold temperature Ts from said temperature measurement.

15. A method according to any one of claims 11 to 14, wherein, after step c), when the temperature measured by the temperature probe (15) is greater than a predetermined cutoff temperature Tf, the auxiliary heating system (15) is stopped.

Images