Flexible and adjustable compensator for microchannel indoor unit

Abstract

A compensator for an indoor unit of a reversible heat pump is disclosed. The compensator includes a conduit having a predefined profile of a first end and a second end. The first end of the conduit is adapted to be fluidly coupled to the thermal expansion device and the primary header of the indoor unit such that the conduit remains above a connection point between the conduit, the thermal expansion device and the primary header. In one or more configurations, the compensator is configured outside the indoor unit. The compensator stores overcharge generated between a heating mode and a cooling mode of the heat pump.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This patent application claims the benefit of U.S. Provisional Patent Application No. 63 / 508,981, filed on June 19, 2023, which is incorporated herein by reference in its entirety. Technical Field

[0002] The present invention relates to the field of heat pumps and, more particularly, to a compensator for an indoor unit of a reversible heat pump. Background Art

[0003] Heat pumps typically have a charge imbalance between heating mode and cooling mode. Existing charge management strategies may not be adequate to store excess charge. Therefore, there is a need to provide a simple, adjustable and cost-effective compensator that can be easily integrated with an indoor unit to achieve charge balance. Summary of the invention

[0004] A compensator for an indoor unit of a reversible heat pump is described herein. The compensator comprises a conduit of a predefined profile having a first end and a second end; wherein the first end of the conduit is adapted to be fluidically coupled to a thermal expansion device and a primary header of the indoor unit such that the conduit is maintained above a connection point between the conduit, the thermal expansion device, and the primary header.

[0005] In one or more embodiments, the conduit is positioned outside the indoor unit.

[0006] In one or more embodiments, the conduit is positioned below the primary header and above the connection point.

[0007] In one or more embodiments, at least a length of conduit is above the primary header.

[0008] In one or more embodiments, the conduit is removably coupled to the indoor unit.

[0009] In one or more embodiments, the first end of the conduit is connected to a predetermined connection point on a supply tube that fluidly connects the thermal expansion device and the primary header such that the conduit is maintained above the predetermined connection point.

[0010] In one or more embodiments, the compensator includes a three-port connector, wherein the first end of the conduit is connected to a first port of the connector, the outlet of the thermal expansion device is connected to a second port of the connector, and the third port of the connector is connected to an inlet of the primary header.

[0011] In one or more embodiments, the duct is adapted to be machined / manufactured with a predefined contour based on an outer contour of a housing of the indoor unit, wherein the duct is wrapped around the housing of the indoor unit.

[0012] In one or more embodiments, the predefined profile of the catheter is a serpentine configuration including a predefined number of turns.

[0013] In one or more embodiments, the predefined profile of the conduit is a vertical configuration.

[0014] In one or more embodiments, the indoor unit is a heat exchanger including an indoor coil comprising a plurality of microchannel tubes, wherein the indoor unit is fluidly connected to an outdoor unit including an outdoor coil comprising a plurality of round tube plate fin tubes.

[0015] In one or more embodiments, the length and inner diameter of the conduit are selected based on the volume difference between the outdoor coil and the indoor coil of the reversible heat pump.

[0016] In one or more embodiments, the conduit is made of one or more of copper, ferrous metals, nonferrous metals, nonmetals, and alloys.

[0017] In one or more embodiments, the catheter is made of a flexible material adapted to adjust to a predefined contour.

[0018] An indoor unit for a reversible heat pump is also described herein. The indoor unit includes a primary header, a secondary header, an indoor coil, and a compensator, the indoor coil including a plurality of microchannel tubes extending between and fluidly coupling the primary header and the secondary header, the compensator including a conduit having a predefined profile with a first end and a second end, wherein the first end of the compensator is adapted to be fluidly coupled to a thermal expansion device and the primary header so that the compensator remains above a connection point between the conduit, the thermal expansion device, and the primary header, and wherein the compensator is positioned outside the indoor unit.

[0019] In one or more embodiments, the indoor unit is fluidly connected to an outdoor unit, the outdoor unit includes an outdoor coil, the outdoor coil includes a plurality of round tube plate fin tubes, and wherein the length and inner diameter of the conduit are selected based on the volume difference between the outdoor coil and the indoor coil of the reversible heat pump.

[0020] In one or more embodiments, the compensator includes a three-port connector, wherein the first end of the conduit is connected to a first port of the connector, the outlet of the thermal expansion device is connected to a second port of the connector, and the third port of the connector is connected to an inlet of the primary header.

[0021] In one or more embodiments, the duct has a predefined contour based on an outer contour of a housing of the indoor unit, wherein the duct wraps around the housing of the indoor unit.

[0022] In one or more embodiments, the predefined profile of the catheter is a serpentine configuration including a predefined number of turns.

[0023] In one or more embodiments, the predefined profile of the conduit is a vertical configuration.

[0024] The foregoing summary is illustrative only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, features, and techniques of the invention will become more apparent from the following description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are included to provide a further understanding of the subject disclosure of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the subject disclosure and together with the description serve to explain the principles of the subject disclosure.

[0026] In the drawings, similar components and / or features may have the same reference numeral. In addition, various components of the same type may be distinguished by having the reference numeral followed by a second reference numeral that distinguishes between similar components. If only the first reference numeral is used in the specification, the description applies to any of the similar components having the same first reference numeral, regardless of the second reference numeral.

[0027] Figure 1A and Figure 1B An exemplary view showing a first design of a compensator implemented in an indoor unit according to one or more embodiments of the present disclosure.

[0028] Figure 1C and Figure 1D An exemplary view showing a second design of a compensator implemented in an indoor unit according to one or more embodiments of the present disclosure.

[0029] Figure 2 An exemplary view illustrating an indoor unit having a compensator configured with a primary header and an expansion device according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0030] The following is a detailed description of the embodiments of the present disclosure depicted in the accompanying drawings. The embodiments are so detailed as to clearly convey the present disclosure. However, the number of details provided is not intended to limit the intended variations of the embodiments; on the contrary, it is intended to cover all modifications, equivalents, and alternatives that fall within the spirit and scope of the subject disclosure as defined by the appended claims.

[0031] Various terms are used herein. To the extent a term used in a claim is not limited below, it should be given the broadest definition persons in the pertinent art would have given that term at the time of filing as reflected in printed publications and issued patents.

[0032] In the specification, when depicting the device in the accompanying drawings, reference may be made to the spatial relationship between various components and the spatial orientation of various aspects of the components. However, as will be recognized by those skilled in the art after reading the subject disclosure in its entirety, the components of the present invention described herein may be positioned in any desired orientation. Therefore, the use of terms such as "above", "below", "upper", "lower", "first", "second" or other similar terms to describe the spatial relationship between various components or to describe the spatial orientation of aspects of such components should be understood to describe the relative relationship between components or the spatial orientation of aspects of such components, respectively, because the auxiliary headers, multi-channel tubes, first and second headers, indoor units, heat exchangers and corresponding components described herein may be oriented in any desired direction.

[0033] An indoor unit such as a microchannel heat exchanger (MCHX) includes a plurality of microchannel tubes having a plurality of inlet ports, which connect an inlet manifold (first header) and an outlet manifold (second header) of the heat exchanger and extend from the inlet manifold (first header) to the outlet manifold (second header) of the heat exchanger. Since the MCHX is used as an indoor unit across various air conditioners and heat pumps, they generally have a charge imbalance between a heating mode and a cooling mode. A heat pump typically has a charge imbalance between a heating mode and a cooling mode, which may be generated due to overcharge generated between the heating mode and the cooling mode.

[0034] Existing charge management strategies are not large enough to store the excess charge of the heat pump. This charge imbalance can damage the indoor unit and the overall cooling and heating system, resulting in a reduction in performance and system shutdown in severe conditions. In addition, the use of microchannel ID coils in the MCHX indoor unit exacerbates this charge imbalance because they have a much smaller internal volume. Therefore, the charge management strategy is the biggest bottleneck in the use of MCHX in heat pumps. The present invention provides a simple, adjustable and cost-effective compensator that can be easily integrated with the indoor unit to achieve charge balance.

[0035] Reference Figure 1A to Figure 1B, a charge compensator 108 for a microchannel indoor unit is disclosed. The indoor unit includes an inlet manifold 102 (hereinafter, also referred to as a first header 102 or a primary header 102), an outlet manifold 104 (hereinafter, also referred to as a second header 104 or a secondary header 104), and a plurality of microchannel tubes 106 extending between the primary header 102 and the secondary header 104 and fluidly connecting the primary header 102 and the secondary header 104. The indoor unit may be associated with a refrigeration system and / or with a heat pump. The indoor unit generally includes a supply pipe 110, which connects the refrigeration line and the thermal expansion device 112 of the indoor unit to the primary header 102. The charge compensator 108 is designed as a conduit (also designated as 108 herein) of a predefined profile (in addition to the primary header 102 and the secondary header 104). The first end of the compensator 108 is adapted to be fluidically coupled to the thermal expansion device 112 and the primary header 102 of the indoor unit so that the conduit (compensator) remains above the connection point 114 between the conduit 108, the thermal expansion device 112 and the primary header 102. In some embodiments, the compensator 108 can be removably coupled to the thermal expansion device 112 and the primary header 102 of the indoor unit from the outside of the indoor unit 102, which allows the compensator 108 to be easily modified with respect to the existing indoor unit. This also reduces the chance of corrosion in the compensator 108, thereby allowing the use of copper or other piping materials in the compensator 108. However, the compensator 108 can also be an integrated part of the indoor unit. The conduit 108 acts as a charge compensator that stores the excess charge generated between the heating mode and the cooling mode of the heat pump.

[0036] The compensator 108 may be positioned at any location outside the indoor unit, as long as at least a length of the compensator 108 remains above the connection point 114 between the compensator 108, the primary header 102, and the expansion device 112. In one or more embodiments, the first end of the conduit may be connected to a predetermined connection point 114 on the supply tube 110, such that the conduit 108 remains above the predetermined connection point 114. In addition, the compensator 108 may include a three-port connector 116 at the predefined connection point 114. The first end of the conduit 108 may be connected to a first port of the connector 116, the outlet of the thermal expansion device 112 may be connected to a second port of the connector 116, and the third port of the connector 116 may be connected to the inlet of the primary header 102, however, the conduit 108 must be positioned above the three-port connector 116.

[0037] In one or more embodiments, Figure 1C and Figure 1D, the conduit 108 may be adapted to be machined / manufactured in a serpentine configuration including a predefined number of turns so that a portion of the conduit 108 remains above the connection point 114. In one or more embodiments, the conduit 108 may be adapted to be machined / manufactured in a predefined profile based on the outer profile of the housing 118 of the indoor unit so that the conduit 108 may be wrapped around the housing 118 of the indoor unit. In one or more embodiments, the conduit 108 may be in a vertical configuration, wherein a first end of the conduit 108 is connected to the connection point 114, and a second end of the conduit 108 extends vertically upward so that the conduit 108 remains above the connection point 114.

[0038] In one or more embodiments, Figure 1A and Figure 1B 1 , the conduit 108 may be a cylindrical shell that is constructed at a predefined height above the primary header 102 (from the horizontal plane of the primary header 102) such that the conduit 108 remains above the connection point 114. An additional tube 120 may be used to fluidly connect the cylindrical compensator 108 to the connection point 114. In some embodiments, the compensator 108 and the primary header 102 may be at the same elevation such that the compensator 108 and the primary header 102 remain in the same horizontal plane, however, the compensator 108 must remain above the connection point 114 between the compensator 108 and the primary header 102. Furthermore, in other embodiments, the compensator 108 may be constructed parallel to the primary header 102 and at a predefined height below the horizontal plane of the primary header 102 without any limitation, however, the compensator 108 must remain above the connection point 114 between the compensator 108 and the primary header 102. Additionally, compensator 108 may be configured non-parallel to primary header 102 such that the longitudinal axes of auxiliary header 108 and primary header 102 remain non-parallel to one another, however, compensator 108 must remain above connection point 114 between the compensator and primary header 102 .

[0039] It should be obvious to those skilled in the art that although for the purpose of simplicity and better explanation, Figures 1A to 1D And some embodiments of the present invention are described in detail for compensators 108 having predefined profiles including wraparound configurations, serpentine configurations, vertical configurations, and horizontal configurations, however, the teachings of the present invention are equally applicable to compensators having other profiles as long as a length of the compensator is maintained above the connection point, and all such embodiments are fully within the scope of the present invention.

[0040] In one or more embodiments, the indoor unit may be a heat exchanger that includes an indoor (ID) coil that includes a plurality of microchannel tubes 106. The indoor unit may be fluidly connected to an outdoor unit that includes an outdoor (OD) coil that includes a plurality of round tube plate fin tubes. The length and inner diameter of the compensator / conduit 108 may be selected based on the volume difference between the outdoor coil and the indoor coil of the reversible heat pump. In addition, the conduit / compensator 108 may be disposed outside the housing 118 of the indoor unit, but proximate to the indoor unit, which may facilitate efficient packaging of the compensator 108 and keeping the overall indoor unit compact.

[0041] In one or more embodiments, the compensator 108 and the primary header 102 may be hollow components having a cylindrical profile. The compensator 108 may be made of a flexible material suitable for adjusting to a predefined profile. The compensator 108 may be one or more of copper, ferrous metals, nonferrous metals, non-metals, and alloys.

[0042] In one or more embodiments, the supply tube 110 may be disposed directly within the primary header 102 via a flat base at one of the ends of the primary header 102 such that a section of the supply tube 110 after the connection point 114 remains parallel to the longitudinal axis of the primary header 102. Furthermore, an additional distributor in the form of a nozzle may be fitted at the outlet of the supply tube 110 within the primary header 102 such that the refrigerant sprayed by the distributor / nozzle within the primary header 102 covers nearly the entire diameter and length of the primary header 102. However, in other embodiments (not shown), the supply tube 110 may have an L-shaped profile, wherein a first section extends upward from the connection point 114, and a second section extends perpendicular to the first section such that the second section of the supply tube 110 remains parallel to the longitudinal axis of the primary header 102.

[0043] In an embodiment, the groove based thereon may be punched out at one end of the compensator 108, and a tube 120 extending from the connection point 114 may be inserted into the compensator 108, followed by brazing the tube 120 to the compensator 108. The ends of the compensator 108 are closed by a cap using a brazing or welding technique to provide a leak-proof compensator. In another embodiment, the connecting tube 120 may also be attached or disposed within the compensator 108 using 3-D printing techniques and other known techniques known in the art.

[0044] Reference Figure 2, showing an exemplary embodiment of an indoor unit 200 of the present invention. The indoor unit 200 includes an inlet manifold 102 (primary header or primary header) and an outlet manifold 104 (secondary header or secondary header), which may preferably be horizontally constructed at the same elevation above the support structure 202, however, in other embodiments, the primary header 102 may also be positioned at an elevated height above the secondary header 104. In addition, the indoor unit 200 includes a plurality of multi-channel tubes "tubes" 106 that are fluidly connected to the primary header 102 and the secondary header 104. The tubes 106 are equally spaced and extend in parallel, wherein one end (first end) of the tube is disposed in the primary header 102, and the other end extends from the primary header 102 at a predefined angle and is further connected to the secondary header 104 and disposed in the secondary header 104, forming a tube structure as shown in FIG. Figure 2 1 , however, the tubes 106 may also extend vertically downward from the primary header 102 to enable fluid flow in a vertically downward direction in the case of a downward fluid flow heat exchanger. In addition, in other embodiments (not shown), the tubes 106 may also extend vertically upward from the primary header 102 to enable fluid flow in a vertically upward direction in the case of an upward fluid flow heat exchanger.

[0045] The indoor unit 200 also includes Figures 1A to 1D The charge compensator 108 of the indoor unit 200 can be designed as a conduit 108 of a predefined profile (in addition to the first and secondary headers 104 of the indoor unit 200). The first end of the conduit 108 is adapted to be fluidly coupled to the thermal expansion device 112 and the primary header 102 of the indoor unit so that the conduit 108 is maintained above the connection point 114 between the conduit 108, the thermal expansion device 112 and the primary header 102. The conduit 108 acts as a charge compensator that stores excess charge generated between the heating mode and the cooling mode of the heat pump, thereby improving the performance, efficiency and life of the overall indoor unit 200 and heat pump.

[0046] The microchannel tube 106 comprises a hollow member, which may preferably have a flat profile with relatively flat walls, however, the tube 106 may also have other profiles without any limitation, and all such embodiments are fully within the scope of the present invention. In addition, the tube 106 comprises a plurality of channels, which are configured in the tube 106 along the axis of the tube 106 and extend in parallel between the first end and the second end of the hollow member, so that a plurality of fluid flow paths of a predefined radius (e.g., generally in the millimeter range) are generated between the first end and the second end of the tube 106, which allows a fluid (such as a refrigerant) to flow from an inlet port of the channel at the first end of the tube 106 to an outlet port of the channel at the second end.

[0047] The tubes 106 are preferably made of a lightweight, thermally conductive, and chemically resistant material; however, the tubes 106 may also be made of other materials within the scope of the present invention. In one embodiment, the tubes 106 may be made of an aluminum extrusion. For ease and clarity of illustration, the tubes 106 are shown in their figures as having a fixed number of channels defining a flow path having a square cross-section. However, it will be understood that in commercial applications (such as, for example, a refrigerant vapor compression system), each multichannel tube 106 typically has about ten to twenty flow channels, but may have more or fewer channels as desired.

[0048] The first end of the tube 106 is suitable for being disposed in the primary header 102 of the indoor unit 200 using brazing technology, 3-D printing technology, and other known technologies known in the art, so that a certain portion of the tube 106 (close to the first end) is disposed in the primary header 102, and the remaining portion of the tube 106 protrudes from the outer surface of the primary header 102 in a downward (or upward) direction to the outside of the primary header 102. In addition, the second end of the tube 106 is suitable for being disposed in the secondary header 104 of the heat exchanger 200 using brazing technology, 3-D printing technology, and other known technologies known in the art, so that a certain portion of the tube 106 (close to the second end) is disposed in the secondary header 104.

[0049] The headers 102, 104 are preferably constructed of cylindrical aluminum tubes / shells with an aluminum brazing coating on their outer surfaces, however, the headers 102, 104 may also have square, rectangular, hexagonal, octagonal or other polygonal cross-sections. On their facing sides, the headers 102, 104 are provided with a series of generally parallel openings for receiving corresponding ends of the tubes 106 so that the ends or sections of the tubes 106 are retained within the headers 102, 104. The tubes 106 are preferably formed from aluminum extrusions. The headers 102, 104 are preferably welded or brazed with the tubes 106. In addition, each of the headers 102, 104 is provided with a substantially spherical dome to improve the pressure resistance of the headers 102, 104. The headers 102, 104 have opposite ends closed by caps brazed or welded thereto. In a preferred embodiment, the various components are all brazed together, and thus, brazing is typically employed to secure the caps to the opposing ends of the headers 102, 104.

[0050] In an embodiment, a slot based on the diameter of the supply tube 110 is punched out at one end of the primary header 102, and the supply tube 110 is inserted into the primary header 102, followed by brazing the supply tube 110 with the primary header 102. An additional distributor or nozzle is fitted at the outlet of the supply tube 110 in the primary header 102, and the end of the primary header 102 is closed by a cap using brazing or welding techniques to provide a leak-proof design. In another embodiment, the supply tube 110 can also be attached or disposed in the primary header 102 using 3-D printing technology and other known techniques known in the art.

[0051] In addition, the indoor unit 200 includes brazed aluminum clad louvered heat sink fins extending in parallel between adjacent microchannel tubes 106. The fins facilitate heat exchange between the fluid flowing through the tubes 106 and the air flowing across the tubes 106 of the indoor unit 200. In addition, the fins also provide structural support and rigidity to the tubes 106 and the heat exchanger 200.

[0052] In one embodiment, Figure 2 As shown in FIG. 1 , the indoor unit 200 may be a V-shaped coil arrangement heat exchanger 200 having a primary header 102 and a secondary header 104 oriented horizontally in the same plane above a support structure. In addition, the tubes 106 protrude from the primary header 102, forming an acute angle with the plane of the primary header 102 in a downward direction, and further extend into the secondary header 104 in an upward direction at the same acute angle, so that a V-shaped coil arrangement of the tubes 106 having a bend at the bottom midpoint of the tube is formed. The bend at the bottom of the tube 106 causes a vertex to be formed at the approximate midpoint of the V-shaped tube 106. The vertex is below the plane defined by the headers 102, 104. In addition, the condensate trough 204 is attached by a fastener along the vertex or bend of the tube, extending along an axis parallel to the longitudinal axis of the headers 102, 104. The trough 204 is configured to collect condensate formed in the tube 106, and the V-shaped coil arrangement facilitates easier flow of the condensate toward the bottom trough 204. Tank 204 may further be provided with one or more condensate outlet 206 fittings to remove collected condensate.

[0053] In one or more embodiments, the indoor unit 200 may be associated with a reversible heat pump and may be further fluidly connected to the outdoor unit of the heat pump via piping, a compressor, a reversing valve, and an expansion device 112. During the cooling mode / cycle, the indoor (ID) coil (microchannel tube) of the indoor unit 200 acts as an evaporator, and the outdoor (OD) coil associated with the outdoor unit acts as a condenser. In addition, during the heating mode / cycle, the ID coil of the indoor unit 200 acts as a condenser, and the OD coil associated with the outdoor unit acts as an evaporator. The heat pump may use a round tube plate fin (RTPF) coil as the OD coil in the outdoor unit, and the microchannel tube of the indoor unit may be an ID coil.

[0054] During the cooling cycle, the liquid refrigerant passes through the expansion device 112, becoming a low-pressure liquid / vapor mixture, which then goes to the ID coil (acting as an evaporator) or the microchannel tube 106 via the supply pipe 110 and the primary header 102, resulting in a uniform two-phase flow. The distributor enhances the port-to-port distribution in the microchannel tube 106 in the primary header 102 without an increase in pressure drop. The liquid refrigerant then flows into the microchannel tube 106, and absorbs heat and boils from the indoor air flowing across the microchannel tube 106 of the indoor unit, thereby becoming a low-temperature vapor. The vapor is then compressed by the compressor, reducing its volume and causing it to heat up. Finally, the gas (which is now hot) passes through the reversing valve to the OD coil (which acts as a condenser). The heat from the hot gas is transferred to the outdoor air, causing the refrigerant to condense into a liquid. The liquid returns to the expansion device 112, and the cycle can be repeated.

[0055] During the heating cycle, the liquid refrigerant passes through the expansion device 112, becoming a low-pressure liquid / vapor mixture, which then goes to the OD coil (which acts as an evaporator). The liquid refrigerant absorbs heat from the outdoor air and boils, becoming a low-temperature vapor. The vapor is then compressed, reducing its volume and causing it to heat up. Finally, the reversing valve sends the gas (which is now hot) to the ID coil (which is a condenser). The heated gas enters the secondary header 104 and flows into the primary header 102 via the microchannel tube / ID coil 106. The heat from the hot gas is transferred to the indoor air flowing across the ID coil 106, causing the refrigerant to condense into liquid. The liquid can then return to the expansion device 112, and the cycle repeats. However, any excess liquid refrigerant generated in the ID coil 106 can be supplied to the compensator 108 via the connection point 114 and the tube 120 and stored in the compensator 108, thereby storing the overcharge. While the compensator 108 remains above the connection point 114 , the liquid refrigerant filled in the compensator 108 may later be supplied back to the expansion device 112 by gravity without using any control strategy.

[0056] Thus, the compensator 108 acts as a passive charge balancing system in the heat pump that can store excess charge generated in the heat pump due to any charge imbalance between the heating cycle and the cooling cycle without any control strategy, thereby improving the performance, efficiency and life of the overall indoor unit and heat pump. In addition, because the compensator 108 facilitates charge balancing in the heat pump, the compensator 108 enables round tube plate fin (RTPF) coils to be used as OD coils in the outdoor unit and enables microchannel tubes to be used as ID coils in the heat pump.

[0057] It should be obvious to those skilled in the art that, although for the purpose of simplicity and better explanation, the figures and some embodiments of the present invention are described in detail with respect to a V-coil arrangement heat exchanger, the teachings of the present invention are equally applicable to other heat exchangers having an upward or downward fluid flow configuration, such as an A-coil heat exchanger, a flat plate design heat exchanger, an N-coil heat exchanger, a J-coil heat exchanger, a U-coil heat exchanger, etc., and all such embodiments are fully within the scope of the present invention.

[0058] Therefore, the present invention overcomes the defects, limitations and shortcomings associated with the prior art by providing a simple, adjustable and cost-effective compensator that can be easily integrated or retrofitted with an indoor unit, which facilitates charge balancing and compensation.

[0059] Although the present invention is described with reference to exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present invention as defined by the appended claims. Modifications may be made to adapt specific circumstances or materials to the teachings of the present invention without departing from the scope of the present invention. Therefore, it is intended that the present invention is not limited to the particular embodiments disclosed, but that the present invention includes all embodiments falling within the scope of the present invention as defined by the appended claims.

[0060] In interpreting the specification, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms "comprises" and "comprising" should be interpreted as referring to elements, components or steps in a non-exclusive manner, indicating that the mentioned elements, components or steps may be present, utilized or combined with other elements, components or steps not explicitly mentioned. In the case where the specification claims refer to at least one of the things selected from the group consisting of A, B, C... and N, the text should be interpreted as requiring only one element from the group, rather than A plus N, or B plus N, etc.

Claims

1. A compensator for an indoor unit of a reversible heat pump, the compensator comprising: a conduit of a predefined profile having a first end and a second end; Wherein, the first end of the conduit is adapted to be fluidly coupled to a thermal expansion device and a primary header of the indoor unit so that the conduit is maintained above a connection point between the conduit, the thermal expansion device, and the primary header.

2. The compensator according to claim 1, wherein: The duct is positioned outside the indoor unit.

3. The compensator according to claim 1, wherein: The conduit is positioned below the primary header and above the connection point.

4. The compensator according to claim 1, wherein: At least a length of the conduit is above the primary header.

5. The compensator according to claim 1, wherein: The conduit is removably coupled to the indoor unit.

6. The compensator according to claim 1, wherein: The first end of the conduit is connected to a predetermined connection point on a supply pipe that fluidly connects the thermal expansion device and the primary header such that the conduit is maintained above the predetermined connection point.

7. The compensator according to claim 1, wherein: The compensator includes a three-port connector, wherein the first end of the conduit is connected to a first port of the connector, an outlet of the thermal expansion device is connected to a second port of the connector, and a third port of the connector is connected to an inlet of the primary header.

8. The compensator according to claim 1, wherein: The duct is adapted to be machined / manufactured with the predefined contour based on an outer contour of a housing of the indoor unit, wherein the duct is wrapped around the housing of the indoor unit.

9. The compensator according to claim 1, wherein: The predefined profile of the conduit is a serpentine configuration including a predefined number of turns.

10. The compensator of claim 1, wherein: The predefined profile of the conduit is a vertical configuration.

11. The compensator of claim 1, wherein: The indoor unit is a heat exchanger including an indoor coil including a plurality of microchannel tubes, wherein the indoor unit is fluidly connected to an outdoor unit including an outdoor coil including a plurality of round tube plate fin tubes.

12. The compensator of claim 1, wherein: The length and inner diameter of the conduit are selected based on a volume difference between the outdoor coil and the indoor coil of the reversible heat pump.

13. The compensator of claim 1, wherein: The conduit is made of one or more of copper, ferrous metal, nonferrous metal, nonmetal and alloy.

14. The compensator of claim 1, wherein: The catheter is made of a flexible material adapted to adjust to the predefined contour.

15. An indoor unit for a reversible heat pump, the indoor unit comprising: Primary header; Secondary headers; an indoor coil including a plurality of microchannel tubes extending between and fluidly coupling the primary header and the secondary header; as well as a compensator comprising a conduit of a predefined profile having a first end and a second end; wherein the first end of the compensator is adapted to be fluidly coupled to a thermal expansion device and the primary header such that the compensator is retained above a connection point between the conduit, the thermal expansion device, and the primary header, and Wherein, the compensator is positioned outside the indoor unit.

16. The indoor unit according to claim 15, wherein: The indoor unit is fluidly connected to an outdoor unit including an outdoor coil comprising a plurality of round tube plate fin tubes, and wherein the length and inner diameter of the conduit are selected based on a volume difference between the outdoor coil and the indoor coil of the reversible heat pump.

17. The compensator of claim 15, wherein: The compensator includes a three-port connector, wherein the first end of the conduit is connected to a first port of the connector, an outlet of the thermal expansion device is connected to a second port of the connector, and a third port of the connector is connected to an inlet of the primary header.

18. The compensator of claim 15, wherein: The duct has the predefined contour based on an outer contour of a housing of the indoor unit, wherein the duct wraps around the housing of the indoor unit.

19. The compensator of claim 15, wherein: The predefined profile of the conduit is a serpentine configuration including a predefined number of turns.

20. The compensator of claim 15, wherein: The predefined profile of the conduit is a vertical configuration.

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