Heat pump

Abstract

A heat pump (1), in particular of the air-water enobloc type, comprising a housing (2) which internally defines a housing compartment (3), wherein the housing (2) comprises at least one base wall (12), the heat pump (1) further comprising a working fluid circuit (9); a refrigerant circuit (4); a first heat exchanger (6); a second heat exchanger (8), wherein the refrigerant circuit (4), the first heat exchanger (6), and the second heat exchanger (8) are housed within the housing compartment (3), wherein the working fluid circuit (9) comprises a lower duct (10) and an upper duct (11) configured to convey the working fluid through the second heat exchanger (8), so as to perform the heat exchange with the refrigerant fluid, wherein the lower duct (10) is configured to convey the working fluid into the second heat exchanger (8), and the upper duct (11) is configured to convey the working fluid out of the second heat exchanger (8), wherein the lower duct (10) is positioned at a lower level with respect to the upper duct (11), with reference to the base wall (12), wherein the heat pump (1) comprises an antifreeze hydraulic assembly (14) comprising an inlet opening (15) and an outlet opening (16), wherein the antifreeze hydraulic assembly (14) is fluidically connected to the working fluid circuit (9) upstream of the second heat exchanger (8), at the lower duct (10), so that the working fluid circuit (9) is configured to circulate the working fluid in succession through the inlet opening (15), the outlet opening (16), and the lower duct (10), and wherein the antifreeze hydraulic assembly (14) comprises a discharge opening (17) and a thermostatic valve (18) positioned at the discharge opening (17) for discharging the working fluid depending on the temperature of the working fluid.

Description

“Heat pump”

[0001] Field of the invention

[0002] The present invention relates to a heat pump, in particular an monobloc airwater heat pump.

[0003] Prior art

[0004] The heat pump is a thermal machine configured to extract and transfer thermal energy. The thermal energy can be extracted, for example, from air, soil or groundwater, and can be used, for example, for heating environments or for domestic hot water.

[0005] Different types of heat pumps exist, including monobloc air-water heat pumps, which allow extracting the energy present in the air and transferring it to water in the form of heat, by means of a single unit that contains within it all the elements of the refrigeration circuit, and which can be placed, for example, outside a building and directly connected to the water system of the plant through pipes that convey the water from the heat pump to the building.

[0006] Monobloc air-water heat pumps have several advantages, including reduced construction complexity due to the fact that all the components are gathered within the single unit, as well as the possibility of being positioned outside the house, thus advantageous in cases where there is not enough space inside the house when the heat pump is not operating.

[0007] Nevertheless, such heat pumps have some drawbacks, including the potential freezing of the water of the system in the event of very cold climates. In fact, the water circuit that connects the heat pump to the building inevitably presents a segment exposed to the external environment which, in the event of sub-zero external temperatures, can lead to localized freezing of the water of the system.

[0008] In order to mitigate or eliminate the risk of freezing, it is known to add glycol, mixed in a certain percentage with respect to the total water volume of the system, so as to lower the freezing temperature of the resulting mixture. However, glycol is a polluting additive and has several drawbacks, including disposal problems, high maintenance costs due to the need for periodically checking the glycol concentration in the system, and the fact that glycol tends to lose its antifreeze properties over time.

[0009] A known alternative to the use of glycol is the introduction of an antifreeze valve on the segment of the water circuit exposed to the external environment. The antifreeze valve locally detects the temperature of the water of the circuit and allows a discharge from the system when it is detected that the temperature of the water reaches a predetermined critical value, for example 3°C. In this way, the formation of ice in thecircuit is prevented, avoiding possible damage to the heat pump and to the water pipes. However, even the use of antifreeze valves has drawbacks, such as the need to intervene on the water circuit at a stage subsequent to the preparation of the heat pump system in order to install the antifreeze valve therein. Moreover, it is necessary to ensure that the antifreeze valve is installed at the lowest point of the segment of the water circuit exposed to the outside, so as to allow a complete drainage of the water of the circuit in case of activation of the antifreeze valve, a requirement that can complicate the installation of the valve.

[0010] Antifreeze valves are also known which integrate therein a sensor for detecting the temperature of the external air. This sensor, in combination with the local sensor for detecting the temperature of the water of the circuit, allows avoiding an undesired activation of the antifreeze valve, with consequent undesired drainage of the water circuit, when the heat pump operates in a cooling mode of the circuit water, in which therefore “false positives” may occur, where the local temperature of the water reaches values close to the critical value of 3°C, but the external air temperature indicates the absence of freezing risks. An antifreeze valve of this type is for example described in EP4006393A1. However, also a valve of this type has several drawbacks, including the need to intervene on the water circuit, at a stage subsequent to the preparation of the heat pump system, in order to install the valve therein.

[0011] It is also provided the possibility of installing such type of valve on a dead branch of the water circuit, in order to avoid having to intervene subsequently on the water circuit. In particular, a valve of this type, comprising a single opening for the inflow and outflow of working fluid, can be mounted in a terminal position of the system. However, such installation in a dead branch of the water circuit causes the local sensor for detecting the temperature of the water to detect a temperature of stagnant water, with low recirculation as it is located in a dead branch of the circuit, and having a temperature that does not reflect the actual temperature of the water flowing in the circuit.

[0012] Moreover, in order to avoid activation in case of “false positive,” this type of valve necessarily requires the integration of an additional component, the sensor for detecting the temperature of the external air, which complicates the configuration of the valve and increases its overall costs.

[0013] There is therefore a need to provide an improved heat pump capable of solving the critical issues highlighted in the prior art.

[0014] Solution

[0015] The object of the present invention is to provide a heat pump, in particular ofthe monobloc air-water type, capable of overcoming the critical issues highlighted in the prior art.

[0016] A further particular object of the present invention is to provide an monobloc air-water heat pump capable of reducing or eliminating the risk of freezing of the water within the water circuit without requiring the addition of polluting additives.

[0017] A further particular object of the present invention is to provide an monobloc air-water heat pump capable of reducing or eliminating the risk of freezing of the water within the water circuit without requiring a subsequent intervention on the water circuit exposed to external air for the integration of any further components.

[0018] A further particular object of the present invention is to provide an monobloc air-water heat pump capable of reducing or eliminating the risk of freezing of the water within the water circuit, while avoiding the risk of “false positives” that can generate an undesired drainage of the water circuit, without necessarily providing for the presence of further sensors, such as for example an external air temperature sensor.

[0019] These and other objects are achieved by means of a heat pump according to claim 1.

[0020] The dependent claims relate to preferred and advantageous embodiments of the present invention.

[0021] Figures

[0022] To better understand the invention and appreciate its advantages, some exemplary and non-limiting embodiments thereof will be described below, with reference to the accompanying figures, in which:

[0023] - Figure 1 is a perspective view of an antifreeze hydraulic assembly, according to one embodiment of the invention;

[0024] - Figure 2 is a perspective view of an antifreeze hydraulic assembly, according to a further embodiment of the invention;

[0025] - Figure 3 is a perspective view of a portion of a heat pump, according to one embodiment of the invention;

[0026] - Figure 4 is a schematic representation of a heat pump, according to one embodiment of the invention;

[0027] - Figure 5 is a schematic perspective view of an assembly of components of a heat pump, according to one embodiment of the invention;

[0028] - Figure 6 is a schematic longitudinal sectional view of a portion of a heat pump, according to one embodiment of the invention;

[0029] - Figure 7 is a perspective view of a portion of a heat pump, according to a further embodiment of the invention;

[0030] - Figure 8 is a perspective view of an antifreeze hydraulic assembly, according to a further embodiment of the invention.

[0031] Description of some preferred embodiments

[0032] Heat pump 1

[0033] In the following description, a heat pump, in particular of the monobloc airwater type, is generally denoted by the reference number 1.

[0034] The heat pump 1 comprises a housing 2. The housing 2 defines therein a housing compartment 3. Furthermore, the housing 2 comprises at least one base wall 12.

[0035] The base wall 12 is adapted to be positioned at the ground and is adapted to support the components of the heat pump 1 positioned in the housing compartment 3. Preferably, the base wall 12 extends substantially on a horizontal plane, i.e. , parallel to the ground.

[0036] The housing 2 further comprises a peripheral wall 13 connected to the base wall 12. Preferably, the peripheral wall 13 extends in a direction transverse to the base wall 12. The base wall 12 and the peripheral wall 13 define at least partially the housing compartment 3.

[0037] The heat pump 1 further comprises a working fluid circuit 9, configured to circulate a working fluid. The working fluid is, for example, water.

[0038] In particular, the working fluid circuit 9 can constitute a portion of a closed circuit for heating the working fluid, suitable for example for transferring or extracting heat from a house.

[0039] The heat pump 1 further comprises a refrigerant circuit 4, configured to circulate a refrigerant fluid. The refrigerant fluid is, for example, propane (R290).

[0040] The heat pump 1 further comprises a first heat exchanger 6, configured to perform a heat exchange between the refrigerant fluid and air. In particular, the first heat exchanger 6 is configured to perform a heat exchange between the refrigerant fluid and air that can be drawn externally to the housing 2, i.e., ambient air.

[0041] The heat pump 1 further comprises a second heat exchanger 8, configured to perform a heat exchange between the working fluid circulating in the working fluid circuit 9 and the refrigerant fluid.

[0042] The refrigerant circuit 4, the first heat exchanger 6, and the second heatexchanger 8 are housed in the housing compartment 3. They are therefore positioned inside the housing 2.

[0043] The working fluid circuit 9 comprises a lower duct 10 and an upper duct 11 , configured to convey the working fluid through the second heat exchanger 8, so as to achieve the heat exchange with the refrigerant fluid.

[0044] The lower duct 10 is configured to convey the working fluid entering the second heat exchanger 8, whereas the upper duct 11 is configured to convey the working fluid exiting the second heat exchanger 8.

[0045] The lower duct 10 is positioned at a lower height than the upper duct 11 , with reference to the base wall 12. Consequently, when the heat pump 1 is installed in an operational configuration, the lower duct 10 is positioned lower than the upper duct 11.

[0046] The heat pump 1 is configured to heat (“heating” mode) or cool (“cooling” mode) the working fluid. Specifically, the heat pump 1 is configured so that, in heating mode, the second heat exchanger 8 acts as a condenser, performing a heating of the working fluid and a consequent cooling of the refrigerant fluid. Conversely, the heat pump 1 is configured so that, in cooling mode, the second heat exchanger 8 acts as an evaporator, performing a cooling of the working fluid and a consequent heating of the refrigerant fluid.

[0047] The heat pump 1 further comprises an antifreeze hydraulic assembly 14, which comprises an inlet opening 15 and an outlet opening 16. The antifreeze hydraulic assembly 14 is fluidically connected to the working fluid circuit 9. In this way, the working fluid enters the antifreeze hydraulic assembly 14 through the inlet opening 15 and exits the antifreeze hydraulic assembly 14 through the outlet opening 16.

[0048] The antifreeze hydraulic assembly 14 is positioned upstream of the second heat exchanger 8. Specifically, the antifreeze hydraulic assembly 14 is positioned at the lower duct 10.

[0049] In this way, the working fluid circuit 9 is configured to circulate the working fluid in sequence through the inlet opening 15, the outlet opening 16, and the lower duct 10.

[0050] The antifreeze hydraulic assembly 14 further comprises a discharge opening 17 and a thermostatic valve 18. The discharge opening 17 is also in fluid connection with the working fluid circuit 9. The thermostatic valve 18 is positioned at the discharge opening 17 for discharging the working fluid as a function of the temperature of the working fluid. In particular, the thermostatic valve 18 is configured to open upon detecting that the working fluid has reached a predetermined temperature, so as to discharge the working fluid outside the working fluid circuit 9 through the discharge opening 17.

[0051] Advantageously, a heat pump 1 so configured eliminates the risk of freezing of the working fluid, for example water, inside the working fluid circuit 9, without requiring the addition of polluting additives.

[0052] With further advantage, a heat pump 1 so configured already integrates within it the components necessary to achieve the thermal transfer to the working fluid, as well as the antifreeze hydraulic assembly 14 in fluid connection with the working fluid circuit 9 arranged inside the housing compartment 3, therefore not requiring an additional or subsequent intervention on the water circuit exposed to external air for the integration of an antifreeze valve, and therefore presenting lower installation complexity.

[0053] With further advantage, a heat pump 1 so configured, with the antifreeze hydraulic assembly 14 integrated into the working fluid circuit 9 passing inside the housing compartment 3, features a thermostatic valve 18 directly exposed to the working fluid circulating through the working fluid circuit 9, and thus detects the temperature of the circulating working fluid and not the temperature of a stagnant working fluid.

[0054] With further advantage, the positioning of the antifreeze hydraulic assembly 14 upstream of the second heat exchanger 8 means that the antifreeze hydraulic assembly 14, when the heat pump 1 operates in “cooling” mode, is exposed to working fluid having a temperature higher than that assumed by the working fluid after the heat exchange inside the second heat exchanger 8. Consequently, the risk of “false positives” that can generate an undesired drainage of the water circuit is minimized or avoided, without necessarily providing for the presence of additional sensors, such as for example an external air temperature sensor. In fact, even in the case in which, in “cooling” mode, the working fluid reaches, at the upper duct 11 , a temperature close to the critical temperature, the temperature of the working fluid detected by the antifreeze hydraulic assembly 14, at the lower duct 10, will certainly be higher and further away from the critical temperature.

[0055] With further advantage, the heat pump 1 so configured allows, in case of critical temperatures, to discharge substantially all of the working fluid from the working fluid circuit 9, thanks to the positioning of the antifreeze hydraulic assembly 14 at the lower duct 10, corresponding to the lowest point of the working fluid circuit 9.

[0056] With further advantage, the heat pump 1 so configured allows the integration of additional components, such as for example sensors or a circulator, in the same antifreeze hydraulic assembly 14.

[0057] According to one embodiment, the inlet opening 15 and the outlet opening 16 of the antifreeze hydraulic assembly 14 are positioned inside the housing 2, in thehousing compartment 3.

[0058] According to one embodiment, the thermostatic valve 18 of the antifreeze hydraulic assembly 14 is positioned inside the housing 2, in the housing compartment 3.

[0059] According to one embodiment, the antifreeze hydraulic assembly 14 is housed in the housing compartment 3. In particular, the entire antifreeze hydraulic assembly 14 is housed inside the housing 2.

[0060] According to one embodiment, the heat pump 1 comprises a compressor 5, configured to perform a compression of the refrigerant fluid.

[0061] Furthermore, the heat pump 1 comprises an expansion device 7, for example an expansion valve or throttling valve, configured to perform an expansion of the refrigerant fluid.

[0062] The compressor 5 and the expansion device 7 are also housed in the housing compartment 3.

[0063] According to one embodiment, the first heat exchanger 6 is a finned tube exchanger.

[0064] According to one embodiment, the second heat exchanger 8 is a brazed plate heat exchanger (BPHE).

[0065] According to one embodiment, the working fluid circuit 9 comprises a circulation pump 19 adapted to act on the working fluid. In particular, the circulation pump 19 is configured to operate the circulation of the working fluid along the working fluid circuit 9, and in particular along the entire closed heating circuit.

[0066] The circulation pump 19 is housed in the housing compartment 3.

[0067] According to one embodiment, the antifreeze hydraulic assembly 14 is positioned interposed between the circulation pump 19 and the second heat exchanger 8.

[0068] Advantageously, this positioning allows to reduce the overall dimensions of the heat pump 1 as well as to position the antifreeze hydraulic assembly 14 at a point of minimum height of the working fluid circuit 9.

[0069] According to one embodiment, the working fluid circuit 9 comprises a flow rate regulator 20. The flow rate regulator 20 is configured to measure and regulate the flow rate of the working fluid circulating in the working fluid circuit 9, and in particular along the entire closed heating circuit.

[0070] The flow rate regulator 20 is housed in the housing compartment 3.

[0071] According to one embodiment, the antifreeze hydraulic assembly 14 ispositioned interposed between the flow rate regulator 20 and the second heat exchanger 8.

[0072] Advantageously, this positioning allows to reduce the overall dimensions of the heat pump 1 as well as to position the antifreeze hydraulic assembly 14 at a point of minimum height of the working fluid circuit 9.

[0073] According to one embodiment, the circulation pump 19 is interposed between the flow rate regulator 20 and the antifreeze hydraulic assembly 14.

[0074] According to one embodiment, the second heat exchanger 8 is positioned facing the peripheral wall 13, preferably secured abutting against the peripheral wall 13.

[0075] In accordance with this embodiment, the lower duct 10 is positioned opposite to the peripheral wall 13 with respect to the second heat exchanger 8.

[0076] Preferably, in accordance with this embodiment, the upper duct 11 is positioned facing the peripheral wall 13 or is positioned passing through the peripheral wall 13. In this way, the upper duct 11 opens out onto the peripheral wall 13.

[0077] According to one embodiment, the lower duct 10 extends substantially along a direction parallel to the plane on which the base wall 12 is substantially extended.

[0078] According to one embodiment, the lower duct 10 extends substantially along a direction transverse to the peripheral wall 13.

[0079] Advantageously, this configuration of the heat pump 1 allows the integration of the antifreeze hydraulic assembly 14 within the housing compartment 3 with reduced bulk as well as to position the antifreeze hydraulic assembly 14 at a point of minimum height of the working fluid circuit 9.

[0080] According to one embodiment, the upper duct 11 extends substantially along a direction parallel to the plane on which the base wall 12 is substantially extended.

[0081] According to one embodiment, the upper duct 11 extends substantially along a direction transverse to the peripheral wall 13.

[0082] According to one embodiment, the working fluid circuit 9 comprises a supply duct 22. The supply duct 22 is configured to convey the working fluid from outside the housing 2 into the housing compartment 3.

[0083] The working fluid circuit 9 extends from the supply duct 22 to the upper duct 11 . Consequently, the working fluid circulating through the working fluid circuit 9 flows in sequence, inside the housing compartment 3, through the supply duct 22, the lower duct 10 and finally the upper duct 11.

[0084] According to one embodiment, the supply duct 22 and the upper duct 11 arepositioned at the same preferably planar, peripheral wall 13, of the housing 2.

[0085] Advantageously, this configuration reduces the bulk of the heat pump 1 .

[0086] The outlet opening 16 of the antifreeze hydraulic assembly 14 is fluidically connected to the lower duct 10.

[0087] According to one embodiment, the outlet opening 16 faces the lower duct 10. Consequently, the outlet opening 16 also faces the second heat exchanger 8.

[0088] According to one embodiment, the lower duct 10 is at least partially inserted into the outlet opening 16 of the antifreeze hydraulic assembly 14.

[0089] According to one embodiment, the lower duct 10 is connected to the outlet opening 16 by means of a fluid connection element 21 , for example a threaded connection element, for example a brass nut.

[0090] According to one embodiment, the portion of the working fluid circuit 9 interposed between the outlet opening 16 and the lower duct 10 is devoid of thermodynamic units or means, in particular active ones, adapted to substantially modify the thermodynamic state of the working fluid. For example, the segment of the working fluid circuit 9 interposed between the outlet opening 16 and the lower duct 10 is devoid of heat exchangers or compressors or pumps or expansion valves or elements adapted to substantially modify the thermodynamic state of the working fluid.

[0091] According to one embodiment, the working fluid circuit 9 is housed, preferably entirely housed, in the housing compartment 3. Specifically, the working fluid circuit 9 constitutes the portion of the closed heating circuit housed inside the housing 2.

[0092] Antifreeze hydraulic assembly 14

[0093] The antifreeze hydraulic assembly 14 is fluidically connected to the working fluid circuit 9. The antifreeze hydraulic assembly 14 is positioned upstream of the second heat exchanger 8, at the lower duct 10 of the heat pump 1 , so as to convey a working fluid in sequence through the inlet opening 15, the outlet opening 16 and the lower duct 10.

[0094] The antifreeze hydraulic assembly 14 comprises a discharge opening 17 and a thermostatic valve 18 positioned at the discharge opening 17 for discharging the working fluid as a function of the temperature of the working fluid.

[0095] According to one embodiment, the antifreeze hydraulic assembly 14 comprises a tubular body 23 extending between the inlet opening 15 and the outlet opening 16.

[0096] Specifically, the tubular body 23 defines a portion of the working fluid circuit 9comprised between the inlet opening 15 and the outlet opening 16.

[0097] According to one embodiment, the tubular body comprises a tubular inlet body 24 and a tubular outlet body 25. The tubular inlet body 24 extends from the inlet opening 15. The tubular outlet body 25 extends from the outlet opening 16. The tubular inlet body 24 and the tubular outlet body 25 are fluidically connected to one another.

[0098] According to one embodiment, the tubular inlet body 24 extends substantially along an axis not parallel to the axis along which the tubular outlet body 25 is substantially extended.

[0099] According to one embodiment, the tubular inlet body 24 extends substantially along an axis incident to the axis along which the tubular outlet body 25 is substantially extended.

[0100] According to one embodiment, the tubular inlet body 24 extends substantially along an axis perpendicular to the axis along which the tubular outlet body 25 is substantially extended.

[0101] According to one embodiment, the tubular inlet body 24 is offset from the tubular outlet body 25, i.e., it extends substantially along an axis neither parallel nor incident to the axis along which the tubular outlet body 25 is substantially extended.

[0102] According to one embodiment, the tubular inlet body 24 extends along a substantially vertical direction, in particular with reference to the plane along which the base wall 12 is substantially extended.

[0103] According to one embodiment, the tubular outlet body 25 extends along a substantially horizontal direction, preferably of minimum height of the working fluid circuit 9. In particular, the tubular outlet body 25 extends along a direction substantially parallel to the plane along which the base wall 12 is substantially extended.

[0104] Advantageously, this configuration of the antifreeze hydraulic assembly 14 allows its easy integration into the working fluid circuit 9, inside the housing compartment 3 of the heat pump 1 , in particular reducing its bulk.

[0105] According to one embodiment, the tubular inlet body 24 and / or the tubular outlet body 25 have a cylindrical shape with circular section or a prismatic shape.

[0106] According to one embodiment, the tubular outlet body 25 is formed in two parts removably connectable to one another.

[0107] According to one embodiment, the tubular outlet body 25 is formed in two parts extending along substantially incident directions. The two parts may present structural continuity or be removably connectable to one another.

[0108] According to one embodiment, the tubular inlet body 24 is fluidically connected to the tubular outlet body 25 at an elbow portion 26.

[0109] Specifically, the tubular inlet body 24 extends from the inlet opening 15 to the elbow portion 26, whereas the tubular outlet body 25 extends from the elbow portion 26 to the outlet opening 25.

[0110] According to one embodiment, the elbow portion 26 defines a connection angle comprised between 120° and 60°, preferably between 100° and 80°, even more preferably of about 90°.

[0111] The connection angle corresponds to the angle definable by the axis along which the tubular inlet body 24 is substantially extended and the axis along which the tubular outlet body 25 is substantially extended.

[0112] According to one embodiment, the tubular inlet body 24, the elbow portion 26 and the tubular outlet body 25 has structural continuity. Specifically, the tubular body 23 is a continuous tubular body curved at the elbow portion 26.

[0113] According to an alternative embodiment, the tubular body 23 comprises a fitting element forming the elbow portion 26 and configured to fluidically connect the tubular inlet body 24 to the tubular outlet body 25.

[0114] According to one embodiment, the tubular inlet body 23 comprises an inlet segment 27 and a fitting segment 28, fluidically connected to one another.

[0115] The inlet segment 27 extends from the inlet opening 15. The fitting segment 28 extends between the inlet segment 27 and the tubular outlet body 25, preferably between the inlet segment 27 and the elbow portion 26.

[0116] According to one embodiment, the tubular body 23 is configured so that:

[0117] - the inlet segment 27 and the fitting segment 28 extend along respective axes incident to and not parallel to each other;

[0118] - the fitting segment 28 and the tubular outlet body 25 extend along respective axes incident to and not parallel to each other;

[0119] - the inlet segment 27 and the tubular outlet body 25 extend along respective axes neither incident nor parallel to each other.

[0120] According to one embodiment, the inlet segment 27 and the tubular outlet body 25 define an angle between 120° and 60°, preferably between 100° and 80°, even more preferably of about 90°, when projected onto a plane that is parallel to both the axis along which the tubular outlet body 25 is substantially extended and the axis along which the inlet segment 27 is substantially extended.

[0121] According to one embodiment, the axis along which the fitting segment 28 is substantially extended and the axis along which the tubular outlet body 25 is substantially extended define an angle between 120° and 60°, preferably between 100° and 80°, even more preferably of about 90°.

[0122] According to one embodiment, the axis along which the inlet segment 27 is substantially extended and the axis along which the fitting segment 28 is substantially extended define an angle between 10° and 45°, or between 15° and 40°, or of about 30°.

[0123] According to one embodiment, the tubular body 23 is made of copper or a copper alloy. Alternatively, the tubular body 23 is at least partially made of composite material.

[0124] According to one embodiment, the discharge opening 17 and the thermostatic valve 18 are positioned at the tubular outlet body 25. Specifically, the discharge opening 17 and the thermostatic valve 18 are fluidically connected to the tubular outlet body 25.

[0125] Advantageously, an antifreeze hydraulic assembly 14 so configured features both reduced bulk, allowing its integration into the heat pump 1 , and the possibility to position the discharge opening 17 and the thermostatic valve 18 at a point of minimum height of the antifreeze hydraulic assembly 14, corresponding to the tubular outlet body 25.

[0126] According to one embodiment, the antifreeze hydraulic assembly 14 comprises a discharge body 29. The discharge opening 17 is defined by the discharge body 29. Furthermore, the thermostatic valve 18 is housed inside the discharge body 29.

[0127] The discharge body 29 is fluidically connected to the tubular outlet body 25. Advantageously, this configuration allows to position the discharge opening 17 and the thermostatic valve 18 at a point of minimum height of the antifreeze hydraulic assembly 14.

[0128] According to one embodiment, the discharge body 29 is a component separate from the tubular body 23 and connectable to the tubular body 23.

[0129] According to one embodiment, the discharge body 29 is made of brass. Alternatively, the tubular body 23 is at least partially made of composite material.

[0130] Advantageously, this configuration allows to house the thermostatic valve 18 inside a component, the discharge body 29, made of a different material from the tubular body 23, and in particular a material having a lower thermal exchange coefficient.

[0131] According to one embodiment, the discharge opening 17 is open along a direction parallel to and separate from the axis along which the tubular outlet body 25 issubstantially extended. Preferably, the discharge opening 17 is also positioned opposite to the tubular inlet body 24 with respect to the tubular outlet body 25. In this way, in the operating position, the discharge opening 17 is positioned at a point of minimum height of the antifreeze hydraulic assembly 14, in particular lower than the tubular outlet body 25.

[0132] According to an alternative embodiment, the discharge opening 17 is open along a direction transverse to the axis along which the tubular outlet body 25 is substantially extended. In this way, in the operating position, the discharge opening 17 is positioned at a point of minimum height of the antifreeze hydraulic assembly 14, in particular lower than the tubular outlet body 25.

[0133] According to one embodiment, the discharge opening 17 is open along a direction transverse to the axis along which the tubular outlet body 25 is substantially extended, and parallel to or coinciding with the axis along which the tubular inlet body 24 is substantially extended.

[0134] According to one embodiment, the antifreeze hydraulic assembly 14 comprises a fluid temperature sensor 30, configured to detect the temperature of the working fluid circulating in the heat pump 1 , in particular circulating in the working fluid circuit 9.

[0135] According to one embodiment, the fluid temperature sensor 30 is a probe immersed in the working fluid circuit 9, intended for reading the temperature of the working fluid entering the second heat exchanger 8. Advantageously, such reading is usable for monitoring the normal operation of the heat pump 1.

[0136] According to one embodiment, the fluid temperature sensor 30 is connected to the antifreeze hydraulic assembly 14 at the tubular outlet body 25.

[0137] According to one embodiment, the fluid temperature sensor 30 is at least partially housed inside the discharge body 29.

[0138] According to a further embodiment, the fluid temperature sensor 30 is positioned extending along a direction parallel to and separate from the axis along which the tubular outlet body 25 is substantially extended, preferably positioned opposite to the tubular inlet body 24 with respect to the tubular outlet body 25, preferably adjacent to the discharge opening 17.

[0139] According to one embodiment, the fluid temperature sensor 30 is positioned along a direction coinciding with the axis along which the tubular outlet body 25 is substantially extended, opposite to the outlet opening 16.

[0140] According to one embodiment not shown, the antifreeze hydraulic assembly14 comprises an air temperature sensor, configured to detect the temperature of the air outside the antifreeze hydraulic assembly 14.

[0141] Advantageously, the second temperature sensor provides a further indication for redundant safety control to avoid possible cases of “false positives.”

[0142] Preferably, when the air temperature sensor is also present, the thermostatic valve 18 is configured to open upon the occurrence of both of the following conditions:

[0143] - when the thermostatic valve 18 detects that the working fluid has reached a first critical or predetermined temperature, and

[0144] - when the air temperature sensor detects that the air has reached a second critical temperature,

[0145] wherein the first critical temperature is different from or equal to the second critical temperature. Preferably, the second critical temperature is lower than the first critical temperature.

[0146] Conversely, when the thermostatic valve 18 detects that the working fluid has reached a first critical or predetermined temperature, but the air temperature sensor does not detect that the air has reached a second critical temperature, or detects an air temperature higher than the second critical temperature, the antifreeze hydraulic assembly 14 is configured to prevent the opening of the thermostatic valve 18.

[0147] According to one embodiment, the antifreeze hydraulic assembly 14 comprises a safety valve 31 , fluidically connected to the tubular body 23. The safety valve 31 is configured to open when the working fluid circulating in the tubular body 23 reaches a predefined critical pressure.

[0148] According to one embodiment, the predefined critical pressure is between 2 and 5 bar, more preferably 3 bar or 4.5 bar.

[0149] According to one embodiment, the safety valve 31 is connected to the antifreeze hydraulic assembly 14 at the tubular inlet body 24, preferably at the fitting segment 28.

[0150] Advantageously, an antifreeze hydraulic assembly 14 so configured allows to integrate a safety valve 31 as well, with reduced overall dimensions.

[0151] According to one embodiment, the safety valve 31 extends substantially in a direction transverse to the fitting segment 28, optionally in a direction opposite to the tubular outlet body 25.

[0152] According to one embodiment, the tubular inlet body 24 forms a housing seat 32, for housing a possible additional sensor.

[0153] Optionally, the housing seat 32 has a tubular shape. Optionally, the housing seat 32 is formed outside the fitting segment 28 and extends in a direction parallel to the fitting segment 28.

[0154] According to one embodiment, the antifreeze hydraulic assembly 14 comprises a vacuum relief valve 33, configured to promote the drainage of working fluid from the discharge opening 17 when the thermostatic valve 18 opens upon detecting that the working fluid has reached a predetermined temperature.

[0155] According to one embodiment, the vacuum relief valve 33 is connected to the antifreeze hydraulic assembly 14 at the tubular outlet body 25.

[0156] According to one embodiment, the vacuum relief valve 33 is at least partially housed inside the discharge body 29.

[0157] According to one embodiment, the vacuum relief valve 33 is positioned opposite to the discharge opening 17 with respect to the tubular outlet body 25.

[0158] According to one embodiment, the vacuum relief valve 33 is positioned extending along a direction transverse to the axis along which the tubular outlet body 25 is substantially extended, optionally along a direction coinciding with the direction along which the discharge opening 17 is open, optionally transverse to the axis along which the fluid temperature sensor 30 is extended.

[0159] Advantageously, an antifreeze hydraulic assembly 14 so configured allows to integrate the plurality of components described above with reduced bulk, and is at the same time integrable into the working fluid circuit 9 of the heat pump 1 .

[0160] According to one embodiment, the antifreeze hydraulic assembly 14 comprises a fluid connection element 21 positioned respectively at the inlet opening 15 and the outlet opening 16.

[0161] The fluid connection element 21 is configured to obtain a fluid connection between the antifreeze hydraulic assembly 14 and the working fluid circuit 9 of the heat pump 1.

[0162] Advantageously, the two fluid connection elements 21 , placed respectively at the inlet opening 15 and the outlet opening 16, allow to integrate the antifreeze hydraulic assembly 14 into a heat pump 1 , in particular into the working fluid circuit 9 in the housing compartment 3 of the heat pump 1.

[0163] According to one embodiment, the fluid connection element 21 is a threaded element screwed respectively at the inlet opening 15 or the outlet opening 16, for example a brass nut.

[0164] According to an alternative embodiment, the fluid connection element 21 is a quick coupling fitting, for example a fitting configured as a fork fitting.

[0165] According to one embodiment, the antifreeze hydraulic assembly 14 comprises a system filling tap 34, configured to allow the filling of the working fluid into the working fluid circuit 9.

[0166] According to one embodiment, the system filling tap 34 is positioned opposite to the tubular outlet body 25 with respect to the tubular inlet body 24.

[0167] According to one embodiment, the system filling tap 34 and the safety valve 31 are connected to the tubular inlet body 24 aligned along a same axis parallel to the axis along which the tubular inlet body 24 is extended.

[0168] According to one embodiment, the system filling tap 34, the safety valve 31 and the fluid temperature sensor 30 are connected to the tubular inlet body 24 aligned along a same axis parallel to the axis along which the tubular inlet body 24 is extended.

[0169] Alternatively, the system filling tap 34 is positioned parallel and adjacent to the tubular outlet body 25 and / or to the fluid temperature sensor 30.

[0170] Alternatively, the system filling tap 34 is positioned along a direction incident to the tubular outlet body 25 and / or to the fluid temperature sensor 30.

[0171] Obviously, a person skilled in the art will be able to make modifications or adaptations to the present invention, without however departing from the scope of the claims set out below.List of references1. Heat pump2. Housing3. Housing compartment4. Refrigerant circuit5. Compressor6. First heat exchanger7. Expansion device8. Second heat exchanger9. Working fluid circuit10. Lower duct11. Upper duct12. Base wall13. Perimetral wall14. Antifreeze hydraulic assembly15. Inlet opening16. Outlet opening17. Discharge opening18. Thermostatic valve19. Circulation pump20. Flow rate regulator21. Fluid connection element22. Inlet duct23. Tubular body24. Tubular inlet body25. Tubular outlet body26. Elbow portion27. Inlet segment28. Fitting segment29. Discharge body30. Air temperature sensor31 . Safety valve32. Housing seat33. Vacuum relief valve34. System filling tap

Claims

Claims1. A heat pump (1), in particular of the monobloc air-water type, comprising a housing (2) defining a housing compartment (3) therein, wherein the housing (2) comprises at least one base wall (12), the heat pump (1) further comprising:- a working fluid circuit (9), configured to circulate a working fluid;- a refrigerant circuit (4), configured to circulate a refrigerant fluid;- a first heat exchanger (6), configured to perform a heat exchange between the refrigerant fluid and air;- a second heat exchanger (8), configured to perform a heat exchange between the working fluid circulating in the working fluid circuit (9) and the refrigerant fluid, wherein the refrigerant circuit (4), the first heat exchanger (6), and the second heat exchanger (8) are housed in the housing compartment (3), wherein the working fluid circuit (9) comprises a lower duct (10) and an upper duct (11) configured to convey the working fluid through the second heat exchanger (8), so as to obtain the heat exchange with the refrigerant fluid, wherein the lower duct (10) is configured to convey the working fluid entering the second heat exchanger (8), and the upper duct (11) is configured to convey the working fluid exiting the second heat exchanger (8), wherein the lower duct (10) is positioned at a lower height than the upper duct (11), with reference to the base wall (12), wherein the heat pump (1) comprises an antifreeze hydraulic assembly (14) comprising an inlet opening (15) and an outlet opening (16), wherein the antifreeze hydraulic assembly (14) is fluidically connected to the working circuit (9) upstream of the second heat exchanger (8), at the lower duct (10), so that the working fluid circuit (9) is configured to circulate the working fluid in sequence through the inlet opening (15), the outlet opening (16), and the lower duct (10), and wherein the antifreeze hydraulic assembly (14) includes a discharge opening (17) and a thermostatic valve (18) positioned at the discharge opening (17) for discharging the working fluid based on the temperature of the working fluid.

2. A heat pump (1) according to claim 1 , wherein the inlet opening (15) and the outlet opening (16) are positioned in the housing compartment (3), and / or wherein the thermostatic valve (18) is positioned in the housing compartment (3).

3. A heat pump (1) according to claim 1 or 2, wherein the antifreeze hydraulic assembly (14) is housed in the housing compartment (3).

4. A heat pump (1) according to any one of the preceding claims, wherein the working fluid circuit (9) comprises a circulation pump (19) adapted to act on the working fluid, wherein the circulation pump (19) is housed in the housing compartment (3), and wherein the antifreeze hydraulic assembly (14) is interposed between the circulation pump (19) and the second heat exchanger (8).

5. A heat pump (1) according to one of claims 1 to 3, wherein the working fluid circuit (9) comprises a flow rate regulator (20) configured to measure and regulate the flow rate of the working fluid circulating in the working fluid circuit (9), wherein the flow rate regulator (20) is housed in the housing compartment (3), and wherein the antifreeze hydraulic assembly (14) is interposed between the flow rate regulator (20) and the second heat exchanger (8), and / or wherein the working fluid circuit (9) comprises a circulation pump (19) adapted to act on the working fluid, wherein the circulation pump (19) is housed in the housing compartment (3), and wherein the circulation pump (19) is interposed between the flow rate regulator (20) and the antifreeze hydraulic assembly (14).

6. A heat pump (1) according to any one of the preceding claims, wherein the housing (2) comprises a peripheral wall (13) connected to the base wall (12), preferably extending in a direction transverse to the base wall (12), wherein the second heat exchanger (8) is positioned facing the peripheral wall (13), preferably secured to abut against the peripheral wall (13), wherein the lower duct (10) is positioned opposite to the peripheral wall (13) with respect to the second heat exchanger (8) and wherein the upper duct (11) is positioned facing the peripheral wall (13), preferably opening out onto the peripheral wall (13).

7. A heat pump (1) according to any one of the preceding claims, wherein the lower duct (10) substantially extends along a direction parallel to the plane on which the base wall (12) substantially extends, and / or wherein the lower duct (10) substantially extends along a direction transverse to a peripheral wall (13) of the housing (2), and / or wherein the upper duct (11) substantially extends along a direction parallel to theplane on which the base wall (12) substantially extends, and / or wherein the upper duct (11) substantially extends along a direction transverse to a peripheral wall (13) of the housing (2).

8. A heat pump (1) according to any one of the preceding claims, wherein the working fluid circuit (9) comprises a supply duct (22) configured to convey the working fluid from outside the housing (2) into the housing compartment (3), wherein the working fluid circuit (9) extends from the supply duct (22) to the upper duct (11), so that the working fluid circulating through the working fluid circuit (9) flows in sequence, inside the housing compartment (3), through the supply duct (22), the lower duct (10), and finally the upper duct (11), and wherein the supply duct (22) and the upper duct (11) are positioned at the same preferably planar, peripheral wall (13), of the housing (2).

9. A heat pump (1) according to any one of the preceding claims, wherein the outlet opening (16) of the antifreeze hydraulic assembly (14) is fluidically connected to the lower duct (10), and wherein the outlet opening (16) faces the lower duct (10) and the second heat exchanger (8), and / or wherein the lower duct (10) is at least partially inserted into the outlet opening (16) of the antifreeze hydraulic assembly (14), and / or wherein the lower duct (10) is connected to the outlet opening (16) by means of a fluid connection element (21), preferably a threaded connection element or a quick coupling fitting.

10. A heat pump (1) according to any one of the preceding claims, wherein the portion of working fluid circuit (9) interposed between the outlet opening (16) and the lower duct (10) has no thermodynamic units or means adapted to substantially modify the thermodynamic state of the working fluid.

11. A heat pump (1) according to any one of the preceding claims, wherein the antifreeze hydraulic assembly (14) comprises a tubular body (23) extending between the inlet opening (15) and the outlet opening (16), wherein the tubular body (23) defines a portion of the working fluid circuit (9) enclosed between the inlet opening (15) and the outlet opening (16), wherein the tubular body comprises a tubular inlet body (24) and a tubular outlet body(25), wherein the tubular inlet body (24) extends from the inlet opening (15), wherein the tubular outlet body (25) extends from the outlet opening (16), wherein the tubular inlet body (24) and the tubular outlet body (25) are fluidically connected to each other, and wherein the tubular inlet body (24) substantially extends along an axis not parallel to the axis along which the tubular outlet body (25) substantially extends, and wherein, optionally, the tubular inlet body (24) substantially extends along an axis incident to the axis along which the tubular outlet body (25) substantially extends.

12. A heat pump (1) according to claim 11 , wherein the tubular inlet body (24) substantially extends along an axis perpendicular to the axis along which the tubular outlet body (25) substantially extends, and / or wherein the tubular inlet body (24) is offset from the tubular outlet body (25), and / or wherein the tubular inlet body (24) extends along a substantially vertical direction, and / or wherein the tubular outlet body (25) extends along a substantially horizontal direction, preferably of minimum height, of the working fluid circuit (9), and / or wherein the tubular inlet body (24) and / or the tubular outlet body (25) are cylindrical in shape with a circular section or are prismatic in shape.

13. A heat pump (1) according to claim 11 or 12, wherein the tubular inlet body (24) is fluidically connected to the tubular outlet body (25) at an elbow portion (26), and wherein the elbow portion (26) defines a connection angle between 120° and 60°, or between 100° and 80°, or of about 90°, and wherein the tubular inlet body (24), the elbow portion (26), and the tubular outlet body (25) have structural continuity, or wherein the tubular body (23) comprises a fitting element forming the elbow portion(26) configured to fluidically join the tubular inlet body (24) to the tubular outlet body (25).

14. A heat pump (1) according to claim 11 , wherein the tubular inlet body (23) comprises an inlet segment (27) and a fitting segment (28), fluidically connected to each other, wherein the inlet segment (27) extends from the inlet opening (15), wherein the fitting segment (28) extends between the inlet segment (27) and the tubular outlet body (25), and wherein the tubular body (23) is configured so that:- the inlet segment (27) and the fitting segment (28) extend along respective axes incident and not parallel to each other;- the fitting segment (28) and the tubular outlet body (25) extend along respective axes incident and not parallel to each other;- the inlet segment (27) and the tubular outlet body (25) extend along respective axes neither incident nor parallel to each other.

15. A heat pump (1) according to claim 14, wherein the inlet segment (27) and the tubular outlet body (25) define an angle between 120° and 60°, or between 100° and 80°, or of about 90° therebetween, when projected onto a plane being parallel to both the axis along which the tubular outlet body (25) substantially extends and the axis along which the inlet segment (27) substantially extends, and / or wherein the axis along which the fitting segment (28) substantially extends and the axis along which the tubular outlet body (25) substantially extends define an angle between 120° and 60°, or between 100° and 80°, or of about 90° therebetween, and / or wherein the axis along which the inlet segment (27) substantially extends and the axis along which the fitting segment (28) substantially extends define an angle between 10° and 45°, or between 15° and 40°, or of about 30° therebetween.

16. A heat pump (1) according to claim 11 , wherein the discharge opening (17) and the thermostatic valve (18) are positioned at the tubular outlet body (25), and / or wherein the antifreeze hydraulic assembly (14) comprises a discharge body (29), wherein the discharge opening (17) is defined by the discharge body (29) and wherein the thermostatic valve (18) is housed inside the discharge body (29), wherein the discharge body (29) is fluidically connected to the tubular outlet body (25), and wherein, optionally, the discharge body (29) is a component separated from the tubular body (23) and is connectable to the tubular body (23).

17. A heat pump (1) according to claim 11 , wherein the discharge opening (17) is open along a direction parallel to and separate from the axis along which the tubular outlet body (25) substantially extends, or wherein the discharge opening (17) is open along a direction transverse to the axis along which the tubular outlet body (25) substantially extends, or wherein the discharge opening (17) is open along a direction transverse to the axis along which the tubular outlet body (25) substantially extends and parallel to or coinciding with the axis along which the tubular inlet body (24) substantially extends.

18. A heat pump (1) according to one of claims 11 to 17, comprising a fluid temperature sensor (30), configured to detect the temperature of the working fluid circulating in the heat pump (1), wherein, optionally, the fluid temperature sensor (30) is connected to the antifreeze hydraulic assembly (14) at a tubular outlet body (25), and / or wherein the fluid temperature sensor (30) is at least partially housed inside a discharge body (29), and / or wherein the fluid temperature sensor (30) is positioned extending along a direction parallel to and separate from the axis along which a tubular outlet body (25) substantially extends, or along a direction transverse to the axis along which the tubular outlet body (25) substantially extends, or along a direction coinciding with the axis along which the tubular outlet body (25) substantially extends and opposite to the outlet opening (16), and / or wherein the antifreeze hydraulic assembly (14) comprises an air temperature sensor configured to detect the temperature of the air outside the antifreeze hydraulic assembly (14), and wherein the thermostatic valve (18) is configured to open when both of the following conditions occur:- when the thermostatic valve (18) detects that the working fluid has reached a first critical or predetermined temperature, and- when the air temperature sensor detects that the air has reached a second critical temperature, wherein the first critical temperature is different from or equal to the second critical temperature, preferably wherein the second critical temperature is lower than the first critical temperature; and / or wherein the antifreeze hydraulic assembly (14) comprises a safety valve (31) fluidically connected to the tubular body (23) and configured to open when the working fluid circulating in the tubular body (23) reaches a predefined critical pressure, and wherein, optionally, the safety valve (31) is connected to the antifreeze hydraulic assembly (14) at the tubular inlet body (24), or at a fitting segment (28), and / or wherein the tubular inlet body (24) forms a housing seat (32), for housing a possible additional sensor, wherein the housing seat (32) is tubular in shape, and optionally is formed outside the fitting segment (28) and extends in a direction parallel to the fitting segment (28), and / orwherein the antifreeze hydraulic assembly (14) comprises a vacuum relief valve (33) configured to promote the drainage of the working fluid from the discharge opening (17) when the thermostatic valve (18) opens, wherein the vacuum relief valve (33) is connected to the antifreeze hydraulic assembly (14) at the tubular outlet body (25), wherein, optionally, the vacuum relief valve (33) is positioned opposite to the discharge opening (17) with respect to the tubular outlet body (25), and / or is positioned extending along a direction transverse to the axis along which the tubular outlet body (25) substantially extends, and / or wherein the antifreeze hydraulic assembly (14) comprises a fluid connection element (21) positioned at the inlet opening (15) and the outlet opening (16), respectively, wherein the fluid connection element (21) is configured to obtain a fluid connection between the antifreeze hydraulic assembly (14) and the working fluid circuit (9), wherein, optionally, the fluid connection element (21) is a threaded element screwed at the inlet opening (15) or the outlet opening (16), respectively, and / or wherein the antifreeze hydraulic assembly (14) comprises a system filling tap (34) configured to allow filling the working fluid circuit (9), optionally positioned opposite to the tubular outlet body (25) with respect to the tubular inlet body (24), with the working fluid.

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