Combined thermodynamic installation for a building

Abstract

Installation (1) comprising: - a refrigerant circuit (2) - an outdoor unit (4) - an indoor unit (6), - a tank (8) - a control unit configured to turn on an auxiliary heating system (16) of the tank (8) when the refrigerant is circulating, the indoor unit valves (11; 12) are open, one of the 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 so as to prevent migration (M) of the refrigerant.

Description

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. Given these factors, it is advantageous to limit the amount of refrigerant in combined heating and cooling systems.

[0005] However, in these limited-refrigerant systems, due to the small quantity of refrigerant, significant amounts of refrigerant can migrate into the storage tank. Specifically, some of the refrigerant in the tank's heat exchanger can liquefy. This excessive refrigerant migration, relative to the total quantity of refrigerant, can lead to system malfunctions and even damage.

[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 addresses 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 heating mode and in a second direction of circulation in cooling mode; an outdoor unit comprising a first heat exchanger in fluid communication with the refrigerant circuit and configured to perform 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 perform heat exchange between the refrigerant and an indoor heating fluid,for example, ambient air in 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 arranged upstream and downstream of the second heat exchanger, in the first direction of refrigerant flow, to regulate the circulation of the refrigerant through the second heat exchanger, a tank valve system comprising a first tank valve and a second tank valve respectively arranged upstream and downstream of the third heat exchanger, in the first direction of refrigerant flow,to regulate the circulation of the refrigerant through the third heat exchanger, the tank includes a water temperature probe in the tank at the level of the third heat exchanger; the tank also includes 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 Tc 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 it is not in operation. This ensures proper system operation and reduces 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 based on the refrigerant pressure measurement taken 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 in order 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 can 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 can include an upper part and a lower part, with the third heat exchanger being positioned in the lower part.

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

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

[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 can 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 and / or second tank valve can be positioned in at least three different positions, particularly to allow for regulation of the refrigerant flow rate. These 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 heating 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 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 perform heat exchange between the refrigerant and an indoor heating fluid.

[0027] The indoor unit can be a wall-mounted unit, typically fixed to an interior wall, commonly used in residential air conditioning systems.

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

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

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

[0031] The indoor unit can 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 notably 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 Tc in the tank at the level of the third heat exchanger using the water temperature probe; c) if the temperature Tc 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 process 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, particularly when the installation is in heating mode.

[0034] The process 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 above 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 the nature of the invention and how it can be implemented. Regarding the accompanying figures: [ Fig. 1 ] illustrates a combined thermodynamic installation for a building according to the invention, [ Fig. 2[ ] shows a schematic view of the domestic hot water storage tank of the installation of the figure 1 , [ Fig. 3 ] presents the installation of the figure 1 in air conditioning mode with potential refrigerant migration, [ Fig. 4 ] shows the installation of the figure 1 in heating mode with potential refrigerant migration, and [ Fig. 5 ] illustrates a variant of a combined dynamic installation for a building according to the invention. Description of method(s) of implementation

[0038] In the following description, identical elements or elements with identical functions are marked with the same reference numeral. For the sake of brevity, they are not described alongside each figure; only the differences between the embodiments are described.

[0039] In the figures, the actual proportions have not always been respected, for the sake of clarity.

[0040] We illustrated to figures 1 and 2 an example of a combined thermodynamic installation 1 according to the invention.

[0041] 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 ( figure 4 ) and in the other direction for air conditioning ( figure 3 ).

[0042] As is known, the compressor system 3 includes, in particular, a compressor 31 and a four-way valve 32 to select the direction of refrigerant flow.

[0043] 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.

[0044] 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.

[0045] The indoor unit 6 can be a wall unit, a console unit, a ducted unit, a cassette unit or a ceiling unit.

[0046] The indoor unit 6 contains a second heat exchanger 7. This second heat exchanger 7 is connected to circuit 2 and allows heat exchange between the refrigerant and an indoor heating fluid, such as the ambient air of the building.

[0047] 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.

[0048] These valves 11 and 12 regulate the circulation of the refrigerant through the second heat exchanger 7.

[0049] Installation 1 also includes a domestic hot water storage tank 8 comprising a tank 10 in which a third heat exchanger 9 extends, as illustrated in particular on the figure 2 .

[0050] Tank 10, for example, has a capacity of 200 L, the invention not being limited to a specific capacity.

[0051] This third heat exchanger 9 is connected to circuit 2 and allows heat exchange between the refrigerant and the domestic hot water present in tank 10 to heat this water.

[0052] 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.

[0053] The first indoor unit valve 11 and the first tank valve 13 are electronic expansion valves, in this example EEV expansion valves (in English " electronic expansion valves ".

[0054] The second indoor unit valve 12 and the second tank valve 14 are solenoid valves and / or solenoid valves.

[0055] Since the purpose of tank 8 is to store hot water, the refrigerant can only circulate in the third heat exchanger when the refrigerant is circulating in circuit 2 in the direction for heating.

[0056] The tank 10 extends along a longitudinal axis X, which is for example vertical, and includes 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.

[0057] 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.

[0058] 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.

[0059] In addition, the tank 8 includes an auxiliary heating system 16 to heat 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.

[0060] Installation 1 may include a refrigerant pressure sensor 17 in circuit 2 near the third heat exchanger 9, for example between the second tank valve 14 and the second indoor unit valve 12.

[0061] Indoor unit 4 may also include a refrigerant temperature probe 30 at the level of indoor unit 4.

[0062] Installation 1 also includes a control unit (not shown) whose operation is described later in the description.

[0063] THE figures 3 and 4 illustrate two different operating modes of installation 1 of the figure 1 for which a risk of refrigerant migration M exists.

[0064] In the Fig. 3 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 take heat from the water present in the tank 10.

[0065] Preferably, in all operating modes of 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 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.

[0066] This operating mode can lead to 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 this point. This can occur, in particular, when the water temperature in the lower part 21 of the tank 10 is low.

[0067] In the Fig. 4Installation 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.

[0068] 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 water temperature in the lower part 21 of the tank 10 is low.

[0069] 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.

[0070] To avoid 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 tank valves 13, 14 is open.

[0071] The process of controlling the installation 1 first includes the circulation of 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.

[0072] Next, the temperature Tc 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.

[0073] If the temperature Tc 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. With condensation prevented, the migration of fluid M is avoided.

[0074] To determine the threshold temperature Ts, the process 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 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.

[0075] 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, particularly when the installation 1 is in heating mode.

[0076] After the heating stage, when the temperature measured by the temperature probe 15 is higher than a predetermined cut-off temperature Tf, the auxiliary heating system 16 is stopped.

[0077] The cutoff temperature Tf is higher than the threshold temperature Ts.

[0078] We illustrated at the figure 5 an installation variant 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 the figure 1 However, the piloting carried out by the piloting unit remains the same.

[0079] The invention has several advantages, including the ability to effectively regulate the temperature of domestic hot water and ambient air in a building, while preventing unwanted migration of refrigerant between heat exchangers.

Claims

1. Combined thermodynamic installation (1) for a building, in particular for heating water for heating 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 heating mode and in a second direction of circulation in cooling mode; - an outdoor unit (4) including a first heat exchanger (5) in fluid communication with the refrigerant circuit (2) and configured to effect 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 perform heat exchange between the refrigerant and an indoor heating fluid, for example, 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 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 arranged upstream and downstream of the second heat exchanger (7), in the first direction of refrigerant flow,to regulate the circulation of the refrigerant through the second heat exchanger (7), - a tank valve system comprising a first tank valve (13) and a second tank valve (14) respectively arranged upstream and downstream of the third heat exchanger (9), in the first direction of refrigerant circulation, to regulate the circulation of the refrigerant through the third heat exchanger (9), the tank (8) comprising a temperature probe (15) of the water in the tank (10) at the level of the third heat exchanger (9), the tank (8) further comprising 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, the first and second indoor unit valves (11; 12) are open, one of the first and second tank valves (13; 14) is closed, and the temperature Tc 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 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) near 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 temperature probe (30) of the refrigerant at the indoor unit (4), 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 indoor unit (4).

6. Installation (1) according to any one of the preceding claims, wherein the tank (10) of the balloon (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 Tc in the tank (10) of the tank (8) at the level of the third heat exchanger (9) using the water temperature probe (15);c) if the temperature Tc is less than or equal to the threshold temperature Ts, turn 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. 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. 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. 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 cut-off temperature Tf, the auxiliary heating system (15) is stopped

Images