Temperature-controlled system with thermally isolated components

Abstract

Exemplary refrigeration apparatus disclosed and described herein has an interior air conditioned space and a refrigeration circuit charged with a refrigerant such as A3. The refrigeration circuit includes a compressor-condenser assembly thermally isolated from the ambient environment of the air conditioned space. An air ramjet chamber structure can thermally isolate the compressor-condenser assembly from the ambient environment of the air conditioned space and can direct heat dissipation from the refrigeration system. In an operational configuration in which the refrigeration system is installed in a structure, the compressor-condenser assembly can be thermally isolated from the ambient environment of the air conditioned space via at least a portion of the structure, such as by positioning the compressor-condenser assembly on an exterior wall of the structure and coupling the compressor-condenser with the refrigeration circuit and the air conditioned space through the wall.

Description

(19) State Intellectual Property Office (12) Invention Patent Application (10) Application Publication Number (43) Application Publication Date (21) Application Number 202580001768.7 (22) Application Date 2025.02.04 (30) Priority Data 63 / 550,024 2024.02.05 US 63 / 721,071 2024.11.15 US (85) PCT International Application Entering National Phase Date 2025.09.12 (86) PCT International Application Application Data PCT / US2025 / 014513 2025.02.04 (87) PCT International Application Publication Data WO2025 / 170944 EN 2025.08.14 (71) Applicant: Refrigeration Solutions Group LLC Address: USA (72) Inventors: L.A. Warren, P. Brossard, K.E. Gambier (74) Patent Agency: Beijing Linda Liu Intellectual Property Agency (General Partnership) 11277 Patent Attorneys: Zhang Huihua, Yue Hongjie (51) Int.Cl. F25D 13 / 00 (2006.01) F25B 41 / 37 (2006.01) F25D 11 / 00 (2006.01) (54) Invention Title: Temperature Control System with Thermally Insulated Components (57) Abstract: The exemplary refrigeration apparatus disclosed and described herein has an internal air-conditioning space and a refrigeration circuit charged with a refrigerant such as A3. The refrigeration circuit includes a compressor-condenser assembly that is thermally isolated from the surrounding environment of the air-conditioning space. An air ram chamber structure can thermally isolate the compressor-condenser assembly from the surrounding environment of the air-conditioning space and can guide heat dissipation from the refrigeration system. In an operational configuration where a refrigeration system is installed in a structure, the compressor-condenser assembly can be thermally insulated from the surrounding environment of the air-conditioned space via at least a portion of the structure, such as by positioning the compressor-condenser assembly on an outer wall of the structure and connecting the compressor-condenser to the refrigeration circuit and the air-conditioned space via said wall. Claims 5 pages, Description 15 pages, Drawings 12 pages, CN 121039451 A 2025.11.28 CN 1 21 03 94 51 A 1. A refrigeration system comprising: an air-conditioned space; and a refrigeration circuit configured to receive A3 refrigerant, wherein the refrigeration circuit includes: a compressor-condenser assembly comprising: a compressor configured to be connected to the refrigeration circuit; and a condenser configured to be connected to the refrigeration circuit, wherein at least a portion of the compressor-condenser assembly is thermally insulated from the surrounding environment of the air-conditioned space. 2. The refrigeration system of claim 1, further comprising an air ram chamber structure configured to thermally insulate the compressor-condenser assembly.3. The refrigeration system of claim 2, wherein the air ram chamber structure is configured to substantially enclose the compressor-condenser assembly. 4. The refrigeration system of any one of claims 2 to 3, wherein the compressor-condenser assembly is configured to be positioned on the top surface of the air-conditioned space, and the air ram chamber structure is configured to be attached to the top surface. 5. The refrigeration system of claim 4, further comprising an evaporator positioned within the air-conditioned space. 6. The refrigeration system of any one of claims 4 to 5, wherein the air ram chamber structure is detachably attached to the top surface of the air-conditioned space. 7. The refrigeration system of any one of claims 4 to 6, wherein the attachment between the air ram chamber structure and the top surface is configured to substantially seal the compressor-condenser assembly within the air ram chamber structure. 8. The refrigeration system of any one of claims 2 to 7, wherein the air ram chamber structure defines: at least one ram chamber inlet fluidly communicating with the external environment of the air ram chamber structure; and at least one ram chamber outlet fluidly communicating with the external environment of the air ram chamber structure. 9. The refrigeration system of claim 8, wherein the external environment of the air ram chamber structure is thermally isolated from the surrounding environment of the air-conditioned space. 10. The refrigeration system of any one of claims 8 to 9, wherein the air ram chamber structure defines a first air ram chamber inlet and a second air ram chamber inlet, both in fluid communication with the external environment of the air ram chamber structure. 11. The refrigeration system of any one of claims 8 to 10, further comprising an exhaust fan connected to the at least one ram chamber outlet, wherein the exhaust fan is configured to drive heated air within the air ram chamber structure to the external environment. 12. The refrigeration system of any one of claims 2 to 11, wherein the temperature within the air ram chamber structure is greater than the temperature of the external environment. 13. The refrigeration system of claim 1, wherein, in an operating configuration where the refrigeration system is installed in a structure, the compressor-condenser assembly is thermally isolated from the surrounding environment of the air-conditioned space via at least a portion of the structure. 14. The refrigeration system of claim 13, wherein the portion of the structure defines: a first surface adjacent to the air-conditioned space; and a second surface opposite to the first surface adjacent to the compressor-condenser assembly. 15. The refrigeration system of any one of claims 13 to 14, wherein the portion of the structure includes an outer wall of the structure.Claims 1 / 5 Page 2 CN 121039451 A 16. The refrigeration system of claim 15, wherein the outer wall defines: a first surface adjacent to the air-conditioning space; and a second surface opposite to the first surface adjacent to the compressor-condenser assembly. 17. The refrigeration system of claim 16, wherein the compressor-condenser assembly is arranged in the external environment of the structure adjacent to the second surface. 18. The refrigeration system of any one of claims 13 to 17, wherein the support structure defines one or more openings configured to receive at least partially a fluid line assembly therein, wherein the fluid line assembly is configured to provide fluid communication between the compressor-condenser assembly and the air-conditioning space through the structure. 19. The refrigeration system of any one of the preceding claims, wherein the compressor-condenser assembly and the refrigeration circuit include a full charge of the A3 refrigerant. 20. The refrigeration system according to any one of the preceding claims, wherein the compressor-condenser assembly further comprises: a first disconnect fitting connecting the compressor input to the refrigeration circuit; and a second disconnect fitting connecting the condenser output to the refrigeration circuit. 21. The refrigeration system according to claim 20, wherein at least one of the first disconnect fitting and the second disconnect fitting is a double-stop quick-disconnect fitting. 22. The refrigeration system according to claim 1, wherein: the condenser further comprises a condenser output communicatively connected to a first end of the capillary tube; and the compressor further comprises a compressor input and a compressor output. 23. The refrigeration system according to claim 22, further comprising an evaporator including an evaporator input and an evaporator output, wherein the evaporator input is communicatively connected to a second end of the capillary tube and the evaporator output is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube. 24. The refrigeration system according to any one of claims 22 to 23, wherein the compressor input is communicatively connected to a second end of the suction line. 25. The refrigeration system according to any one of claims 22 to 24, wherein the compressor output is communicatively connected to the condenser. 26. The refrigeration system according to any one of claims 23 to 25, wherein the portion of the suction line and the portion of the capillary tube are adjacent to or connected to a heat exchanger. 27. The refrigeration system according to any one of claims 22 to 26, wherein the compressor input is communicatively connected to the suction line via a first disconnect fitting.28. The refrigeration system according to any one of claims 21 to 27, wherein the condenser outlet is communicatively connected to the capillary tube. 29. The refrigeration system according to any one of the preceding claims, further comprising a controller connected to a power source. 30. The refrigeration system according to any one of the preceding claims, wherein the A3 refrigerant has a Global Warming Potential (GWP) value of less than 10. 31. The refrigeration system according to any one of the preceding claims, wherein the refrigeration system further comprises a maximum charge of 5.3 ounces (150 grams) of the A3 refrigerant per compressor. 32. The refrigeration system according to any one of the preceding claims, wherein the A3 refrigerant comprises propane. Claims 2 / 5 pages 3 CN 121039451 A 33. The refrigeration system according to any one of the preceding claims, wherein the refrigeration circuit is formed as part of a walk-in refrigeration unit. 34. A refrigeration system configured to receive a refrigerant, the refrigeration system comprising: a condenser including a condenser outlet communicatively connected to a first end of a capillary tube; and an evaporator including an evaporator inlet and an evaporator outlet, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube. 35. The refrigeration system of claim 34, further comprising a compressor including a compressor inlet and a compressor outlet. 36. The refrigeration system of any one of claims 34 to 35, wherein the compressor inlet is communicatively connected to the second end of the suction line. 37. The refrigeration system of any one of claims 34 to 36, wherein the compressor outlet is communicatively connected to the condenser. 38. The refrigeration system of any one of claims 34 to 37, further comprising an air-conditioned space, wherein the evaporator is located within the air-conditioned space and the condenser is located outside the air-conditioned space or physically separated from the evaporator by a structure. 39. The refrigeration system of any one of claims 34 to 38, wherein the refrigerant has a Global Warming Potential (GWP) value of less than 10. 40. The refrigeration system of any one of claims 34 to 39, wherein the refrigerant is classified as an A3 refrigerant. 41. The refrigeration system of claim 40, wherein the refrigeration system further comprises a maximum charge of 5.3 ounces of the A3 refrigerant per compressor. 42. The refrigeration system of any one of claims 34 to 41, further comprising a controller connected to a power source. 43. The refrigeration system of any one of claims 34 to 42, wherein the refrigerant comprises propane.44. The refrigeration system of any one of claims 34 to 43, wherein the portion of the suction line and the portion of the capillary tube are adjacent to or connected to a heat exchanger. 45. A walk-in refrigeration unit comprising: one or more refrigeration systems configured to receive a refrigerant, wherein each refrigeration system includes: a condenser including a condenser outlet communicatively connected to a first end of a capillary tube; and an evaporator including an evaporator inlet and an evaporator outlet, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of the suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube. 46. The walk-in refrigeration unit of claim 45, further comprising a compressor including a compressor inlet and a compressor outlet. 47. The walk-in refrigeration unit of any one of claims 45 to 46, wherein the compressor inlet is communicatively connected to the second end of the suction line. 48. The walk-in refrigeration unit of any one of claims 45 to 47, wherein the compressor output is communicatively connected to the condenser. 49. The walk-in refrigeration unit of any one of claims 45 to 48, further comprising an air-conditioning space, wherein the evaporator is located within the air-conditioning space and the condenser is located outside the air-conditioning space or physically separated from the evaporator by a structure. 50. The walk-in refrigeration unit of any one of claims 45 to 49, wherein the refrigerant has a Global Warming Potential (GWP) value of less than 10. 51. The walk-in refrigeration unit of any one of claims 45 to 50, wherein the refrigerant is classified as A3 refrigerant. 52. The walk-in refrigeration unit of any one of claims 45 to 51, wherein the one or more refrigeration systems further include a maximum charge of 5.3 ounces of the A3 refrigerant per compressor. 53. The walk-in refrigeration unit of any one of claims 45 to 52, further comprising a controller connected to a power source. 54. The walk-in refrigeration unit according to any one of claims 45 to 53, wherein the refrigerant comprises propane. 55. The walk-in refrigeration unit according to any one of claims 45 to 54, wherein the portion of the suction line and the portion of the capillary tube are adjacent to or connected to a heat exchanger.56. A method of cooling a walk-in refrigeration unit, the method comprising: providing one or more refrigeration systems, wherein each refrigeration system includes: a condenser including a condenser outlet communicatively connected to a first end of a capillary tube; and an evaporator including an evaporator inlet and an evaporator outlet, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube. 57. The method of claim 56, wherein each refrigeration system further includes a compressor including a compressor inlet and a compressor outlet. 58. The method of any one of claims 56 to 57, wherein the compressor inlet is communicatively connected to the second end of the suction line. 59. The method of any one of claims 56 to 58, wherein the compressor outlet is communicatively connected to the condenser. 60. The method of any one of claims 56 to 59, wherein the walk-in refrigeration unit further comprises an air-conditioning space, wherein the evaporator is located within the air-conditioning space and the condenser is located outside the air-conditioning space or physically separated from the evaporator by a structure. 61. The method of any one of claims 56 to 60, wherein each refrigeration system further comprises a controller coupled to a power source. 62. The method of any one of claims 56 to 61, wherein the portion of the suction line and the portion of the capillary tube are adjacent to or coupled to a heat exchanger. 63. The method of any one of claims 56 to 62, wherein each refrigeration system is configured to receive a refrigerant having a Global Warming Potential (GWP) value of less than 10. 64. The method of any one of claims 56 to 63, wherein each refrigeration system is configured to receive a refrigerant classified as A3 refrigerant. 65. The method of any one of claims 56 to 64, wherein each refrigeration system further comprises a maximum charge of 5.3 ounces of the A3 refrigerant per compressor. Claims 4 / 5, page 5, CN 121039451, A 66. The method according to any one of claims 56 to 65, wherein each refrigeration system is configured to receive a refrigerant comprising propane.Claims 5 / 5 Page 6 CN 121039451 A Temperature control system with thermally insulated components

[0001] Cross-reference to related applications

[0002] This international application claims priority to U.S. Provisional Patent Application No. 63 / 550,024, filed February 5, 2024, and U.S. Provisional Patent Application No. 63 / 721,071, filed November 15, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to refrigeration systems. In particular, the disclosed system includes an air-conditioned space and refrigeration circuit components (e.g., compressor, condenser, etc.), the refrigeration circuit components being thermally insulated from the surrounding environment of the air-conditioned space and / or its refrigeration circuit utilizing capillary tubes instead of liquid lines thermally coupled to suction lines. Background Art

[0004] Refrigeration systems (e.g., walk-in cold storage rooms, etc.) and / or the like are used in various environments (e.g., retail environments, kitchens, etc.) to provide refrigerated (e.g., air-conditioned) space for refrigerated goods (such as food). Refrigeration systems operate by using cooled air circulating around the goods to keep the goods below ambient temperature. For example, below ambient temperature includes being at or below 40°F (4.4°C) or at or below 0°F (-17.8°C), and combinations of both within the same air-conditioned space. Refrigeration systems may include air-conditioned spaces (or storage spaces) and openings such as doors that allow access to the food contained therein. Cooling of the refrigeration system may be provided by heat exchange with an endothermic heat exchanger (such as an evaporator as an endothermic heat exchanger) in the refrigeration loop of the refrigeration system. The refrigeration loop may further include a condenser as a radiative heat exchanger. Summary of the Invention

[0005] A simplified summary of one or more examples of the present disclosure is given below to provide a basic understanding of these examples. This abstract is not a broad overview of all the envisioned examples, and is not intended to define the key or critical elements of all examples, nor to indicate the scope of any or all examples. Its sole purpose is to present some concepts of one or more examples in a simplified form as a prelude to the more detailed descriptions that follow.

[0006] As described below, the systems of this disclosure utilize capillary tubes for expansion devices. In one example, the split-type refrigeration system of this disclosure reduces the size of the liquid line or any facility that leaves the condenser outlet and enters a conventional expansion valve. By minimizing the liquid line, the charge in the condenser and evaporator is increased. Thus, this disclosure enables a refrigeration system with a larger capacity while allowing for the regulation of a small amount of working refrigerant. Because there is no additional piping system to reduce airflow as in conventional self-contained refrigeration systems, the systems of this disclosure are an improvement on existing systems.

[0007] Furthermore, as will be more fully explained below, embodiments of this disclosure can operate at least a portion of components of a thermally isolated refrigeration circuit, such as a removably attached compressor and condenser. As an example, in some embodiments, the refrigeration system described herein may include an air ram chamber structure fixed to or otherwise enclosing the compressor-condenser assembly. Specifically, an exemplary compressor-condenser assembly may be positioned on the top surface of an air-conditioned space (e.g., on the outer surface of a housing defining the conditioned space), and the air ram chamber structure may be attached to the top surface of the air-conditioned space such that the compressor-condenser assembly is disposed therein. Heat dissipation from the compressor-condenser assembly can be exhausted to the external environment of the air ram chamber, which is further thermally isolated from the surrounding environment of the air-conditioned space. In other words, the surrounding environment of the air-conditioned space may refer to the occupancy or interior of the structure in which the refrigeration system operates, such that the external environment of the thermal isolation of the air ram chamber structure may refer to the environment outside the occupancy (e.g., the outside world).

[0008] In some examples, a refrigeration system is provided. The refrigeration system may include an air-conditioned space and a refrigeration circuit configured to receive A3 refrigerant. The refrigeration circuit may include a compressor-condenser assembly, which includes a compressor configured to be coupled to the refrigeration circuit and a condenser configured to be coupled to the refrigeration circuit. The compressor-condenser assembly may be thermally insulated from the surrounding environment of the air-conditioned space.

[0009] In some aspects, alone or in combination with any of the foregoing aspects, the refrigeration system may include an air ram chamber structure configured to thermally insulate the compressor-condenser assembly.

[0010] In some aspects, alone or in combination with any of the foregoing aspects, the air ram chamber structure may be configured to substantially enclose the compressor-condenser assembly.

[0011] In some aspects, alone or in combination with any of the foregoing aspects, the compressor-condenser assembly may be configured to be positioned on the top surface of the air-conditioned space, and the air ram chamber structure may be configured to be attached to said top surface.

[0012] In some aspects, alone or in combination with any of the foregoing aspects, the refrigeration system may also include an evaporator configured to be positioned within the air-conditioned space.

[0013] In some aspects, alone or in combination with any of the foregoing aspects, the air ram chamber structure may be detachably attached to the top surface of the air-conditioned space.

[0014] In some aspects, alone or in combination with any of the foregoing aspects, the attachment between the air ram chamber and the top surface of the air-conditioned space may be configured to seal the compressor-condenser assembly within the air ram chamber structure.

[0015] In some aspects, alone or in combination with any of the preceding aspects, the air ram chamber structure may define at least one ram chamber inlet in fluid communication with an external environment of the air ram chamber structure and at least one ram chamber outlet in fluid communication with an external environment of the air ram chamber structure.

[0016] In some aspects, alone or in combination with any of the preceding aspects, the air ram chamber structure may define a first air ram chamber inlet and a second air ram chamber inlet, each of which is in fluid communication with an external environment of the air ram chamber structure.

[0017] In some aspects, alone or in combination with any of the preceding aspects, the external environment of the air ram chamber structure may be thermally isolated from the surrounding environment of the air-conditioned space.

[0018] In some aspects, alone or in combination with any of the preceding aspects, the refrigeration system may further include an exhaust fan coupled to at least one ram chamber outlet. The exhaust fan may be configured to force heated air within the air ram chamber structure to the external environment.

[0019] In some aspects, alone or in combination with any of the foregoing aspects, the temperature inside the air ram chamber may be greater than the temperature of the external environment.

[0020] Additionally or alternatively, in some aspects, alone or in combination with any of the foregoing aspects, in an operating configuration in which the refrigeration system is installed in the structure, the compressor-condenser assembly may be thermally insulated from the surrounding environment of the air-conditioned space via at least a portion of the structure.

[0021] In some aspects, alone or in combination with any of the foregoing aspects, this portion of the structure may define a first surface adjacent to the air-conditioned space and a second surface opposite to the first surface adjacent to the compressor-condenser assembly.

[0022] In some aspects, alone or in combination with any of the foregoing aspects, said portion of the structure may include an outer wall of the structure described in the specification (page 2 / 15, CN 121039451 A).

[0023] In some aspects, alone or in combination with any of the foregoing aspects, the outer wall may define a first surface adjacent to the air-conditioned space and a second surface opposite to the first surface adjacent to the compressor-condenser assembly.

[0024] In some aspects, alone or in combination with any of the foregoing aspects, the compressor-condenser assembly may be arranged in the external environment of the structure near the second surface.

[0025] In some aspects, alone or in combination with any of the foregoing aspects, the support structure may define one or more openings configured to at least partially receive a fluid line assembly. The fluid line assembly may be configured to provide fluid communication between the compressor-condenser assembly and the air-conditioned space through the structure.

[0026] In some aspects, alone or in combination with any of the foregoing aspects, the compressor-condenser assembly and the refrigeration circuit may include a fully charged A3 refrigerant.

[0027] In some aspects, alone or in combination with any of the foregoing aspects, the compressor-condenser assembly may further include a first disconnect fitting connecting the compressor input to the refrigeration circuit and a second disconnect fitting connecting the condenser output to the refrigeration circuit.

[0028] In some aspects, alone or in combination with any of the foregoing aspects, at least one of the first and second disconnect fittings may be a double-stop quick-disconnect fitting.

[0029] In some aspects, alone or in combination with any of the foregoing aspects, the condenser may further include a condenser output communicatively connected to a first end of the capillary tube, and the compressor may further include a compressor input and a compressor output.

[0030] In some aspects, alone or in combination with any of the foregoing aspects, the refrigeration system may include an evaporator, the evaporator including an evaporator input and an evaporator output. The evaporator input may be communicatively connected to a second end of the capillary tube, and the evaporator output may be communicatively connected to a first end of the suction line. At least a portion of the suction line and at least a portion of the capillary tube may be thermally coupled.

[0031] In some aspects, alone or in combination with any of the preceding aspects, the compressor input may be communicatively connected to a second end of the suction line.

[0032] In some aspects, alone or in combination with any of the preceding aspects, the compressor output may be communicatively connected to a condenser.

[0033] In some aspects, alone or in combination with any of the preceding aspects, this portion of the suction line and this portion of the capillary tube may be adjacent to or connected to a heat exchanger.

[0034] In some aspects, alone or in combination with any of the preceding aspects, the compressor input may be communicatively connected to the suction line via a first disconnect fitting.

[0035] In some aspects, alone or in combination with any of the preceding aspects, the condenser output may be communicatively connected to a capillary tube.

[0036] In some aspects, alone or in combination with any of the preceding aspects, the refrigeration system may also include a controller connected to a power source.

[0037] In some aspects, alone or in combination with any of the preceding aspects, the A3 refrigerant may have a Global Warming Potential (GWP) value of less than 10.

[0038] In some aspects, alone or in combination with any of the foregoing aspects, the refrigeration system may also include a maximum charge of 5.3 ounces (150 grams) of A3 refrigerant per compressor.

[0039] In some aspects, alone or in combination with any of the foregoing aspects, the A3 refrigerant may include propane.

[0040] In some examples, a refrigeration system is provided.The refrigeration system is configured to receive refrigerant and includes: a condenser, as described on page 3 / 15 of CN 121039451 A, comprising a condenser outlet communicatively connected to a first end of a capillary tube; and an evaporator, comprising an evaporator inlet and an evaporator outlet, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line and at least a portion of the capillary tube are thermally connected.

[0041] In some aspects, alone or in combination with any of the preceding aspects, the refrigeration circuit includes a compressor, the compressor comprising a compressor inlet and a compressor outlet. In one aspect, alone or in combination with any of the preceding aspects, the compressor inlet is communicatively connected to a second end of a suction line. In one aspect, alone or in combination with any of the preceding aspects, the compressor outlet is communicatively connected to the condenser.

[0042] In some aspects, alone or in combination with any of the preceding aspects, the refrigeration system further includes an air-conditioned space, wherein the evaporator is located within the air-conditioned space and the condenser is located outside the air-conditioned space, or physically separated from the evaporator by a structure.

[0043] In some aspects, alone or in combination with any of the preceding aspects, the refrigerant has a Global Warming Potential (DWP) value of less than 10. In one aspect, alone or in combination with any of the preceding aspects, the refrigerant is classified as an A3 refrigerant. In one aspect, alone or in combination with any of the preceding aspects, the refrigeration system further includes a maximum charge of 5.3 ounces of A3 refrigerant per compressor. In one aspect, alone or in combination with any of the preceding aspects, the refrigerant includes propane.

[0044] In some aspects, alone or in combination with any of the preceding aspects, the refrigeration system further includes a controller coupled to a power source. In one aspect, alone or in combination with any of the preceding aspects, this portion of the suction line and this portion of the capillary tube are adjacent to or coupled to a heat exchanger.

[0045] In some examples, a walk-in refrigeration unit is also provided. A walk-in refrigeration unit includes one or more refrigeration systems configured to receive refrigerant, wherein each refrigeration system includes: a condenser including a condenser outlet communicatively connected to a first end of a capillary tube; and an evaporator including an evaporator inlet and an evaporator outlet, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube.

[0046] In some examples, a method for cooling a walk-in refrigeration unit is provided.The method includes: providing one or more refrigeration systems, wherein each refrigeration system includes: a condenser including a condenser outlet communicatively connected to a first end of a capillary tube; an evaporator including an evaporator inlet end and an evaporator outlet end, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube.

[0047] In some examples, a refrigeration system is provided. The refrigeration system is configured to receive a refrigerant and includes: a condenser including a condenser outlet communicatively connected to a first end of a capillary tube; an evaporator including an evaporator inlet and an evaporator outlet, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube.

[0048] In some aspects, alone or in combination with any of the foregoing aspects, a refrigeration circuit includes a compressor including an inlet and a compressor outlet. In one aspect, alone or in combination with any of the preceding aspects, the compressor inlet is communicatively connected to a second end of the suction line. In one aspect, alone or in combination with any of the preceding aspects, the compressor outlet is communicatively connected to the condenser.

[0049] In some aspects, alone or in combination with any of the preceding aspects, the refrigeration system further includes an air-conditioning space, wherein the evaporator is located within the air-conditioning space and the condenser is located outside the air-conditioning space, or physically separated from the evaporator by a structure.

[0050] In some aspects, alone or in combination with any of the preceding aspects, the refrigerant has a Global Warming Potential (GWP) value of less than 10. In one aspect, alone or in combination with any of the preceding aspects, the refrigerant is classified as an A3 refrigerant. In one aspect, alone or in combination with any of the preceding aspects, the refrigeration system further includes a maximum charge of 5.3 ounces of A3 refrigerant per compressor. In one aspect, alone or in combination with any of the preceding aspects, the refrigerant includes propane.

[0051] In some aspects, alone or in combination with any of the preceding aspects, the refrigeration system also includes a controller connected to a power source. In one aspect, alone or in combination with any of the preceding aspects, this portion of the suction line and this portion of the capillary tube are adjacent to or connected to a heat exchanger.

[0052] In some examples, a walk-in refrigeration unit is also provided.The walk-in refrigeration unit includes one or more refrigeration systems configured to receive refrigerant, wherein each refrigeration system includes: a condenser including a condenser outlet communicatively connected to a first end of a capillary tube; and an evaporator including an evaporator inlet and an evaporator outlet, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube.

[0053] In some examples, a method of cooling a walk-in refrigeration unit is provided. The method includes: providing one or more refrigeration systems, wherein each refrigeration system includes: a condenser including a condenser outlet communicatively connected to a first end of a capillary tube; and an evaporator including an evaporator inlet and an evaporator outlet, wherein the evaporator inlet is communicatively connected to a second end of the capillary tube and the evaporator outlet is communicatively connected to a first end of a suction line, wherein at least a portion of the suction line is thermally connected to at least a portion of the capillary tube.

[0054] The features, functions, and advantages discussed may be implemented independently in various examples of this disclosure, or may be combined with other examples, as can be seen from the following description and accompanying drawings. Brief Description of the Drawings

[0055] Certain exemplary embodiments of this disclosure have been described in the general terms described above, and reference will now be made to the accompanying drawings. Components shown in the figures may or may not be present in some embodiments described herein. Some embodiments may include fewer (or more) components than those shown in the figures.

[0056] FIG1 is a block diagram illustrating a refrigeration system according to an example of this disclosure;

[0057] FIGS. 2A through 2F are block diagrams illustrating examples of heat exchange configurations of a refrigeration system according to this disclosure;

[0058] FIG3 illustrates a walk-in refrigeration unit according to an example of this disclosure;

[0059] FIGS. 4A through 4C illustrate detailed views of exemplary system component groups according to an example of this disclosure; and

[0060] FIG. 4D illustrates a detailed view of another exemplary system component group according to an example of this disclosure.

[0061] Figures 5A and 5B illustrate exemplary quick-disconnect fittings according to an example of the present disclosure;

[0062] Figures 6A and 6B illustrate exemplary air ram chamber structures according to an example of the present disclosure;

[0063] Figure 7 illustrates an exemplary structural installation (e.g., operational configuration) of a refrigeration system with thermal insulation according to an example of the present disclosure; and

[0064] Figure 8 illustrates a transport configuration of the exemplary refrigeration system of Figure 7 according to an example of the present disclosure.Detailed Description

[0065] Overview

[0066] Embodiments of this disclosure pertain to refrigeration systems for temperature-controlled areas or air-conditioned spaces (e.g., walk-in refrigeration units, see page 5 / 15 of specification, CN 121039451 A). In some embodiments, the refrigeration system can thermally insulate at least a portion of the components of the refrigeration circuit from the surrounding environment of the air-conditioned space (e.g., occupancy or interior of a structure). The refrigeration systems of this disclosure provide maximized air-conditioned space in air-conditioned areas by allowing the condenser unit to be removably connected / disconnected from the refrigeration circuit for installation. As described below, a split refrigeration system (e.g., the exemplary refrigeration system of this disclosure) or a walk-in cooler or refrigerator using A3 refrigerant (e.g., R290, etc.) is provided, which has little impact on global warming for medium and small walk-in refrigeration. The refrigeration systems of this disclosure utilize capillary tubes for expansion devices. In one example, the refrigeration systems of this disclosure (e.g., split refrigeration systems) minimize the size of liquid lines or any devices leaving the condenser outlet and heading towards a conventional expansion valve. By minimizing liquid lines and removing thermal expansion valves, the charge in the condenser and evaporator is increased. Therefore, this disclosure provides greater capacity to the refrigeration system while allowing for the regulation of small amounts of working refrigerant. Because there is no additional piping system to reduce airflow as in conventional self-contained refrigeration systems, the system of this disclosure is an improvement over existing systems.

[0067] Examples of this disclosure also point to refrigeration systems using A3-classified refrigerants (according to UL60335-2-89) in walk-in refrigeration units. In one example, the refrigerant is R290 (i.e., propane), an ultra-low GWP (global warming potential) refrigerant that, when used in a refrigeration system, reduces both energy consumption and global warming. Because R290 is classified as a flammable refrigerant, the amount that can be safely used in a refrigeration circuit is limited. For example, in the United States, the current charge limit for R290 is 150 grams (5.3 ounces) per compressor. This charge limit typically limits the refrigeration capacity of systems using R290 as a refrigerant. Therefore, it is necessary to increase the cooling capacity of the system without increasing the refrigerant charge. Examples of this disclosure point to a refrigeration system that utilizes small-diameter lines, such as capillary tubes, instead of conventional liquid lines to increase the cooling capacity of a walk-in unit. Thus, this disclosure provides a refrigeration system that achieves high cooling capacity while utilizing the environmentally friendly A3 refrigerant, thereby reducing environmental impact compared to conventional refrigeration systems.

[0068] In one example, the system of this disclosure includes a condenser configured to be positioned at the top of an air-conditioned space (e.g., on any outer surface defining the air-conditioned space), wherein the condenser is detachably coupled to a refrigeration circuit.In one example, the condenser is detachably coupled to the refrigeration circuit using a quick-disconnect connection (e.g., a quick-disconnect assembly as defined herein). In one example, the system of this disclosure includes one or more evaporator units located within an air-conditioned space.

[0069] Furthermore, and as will be more fully explained below, embodiments of this disclosure can operate to thermally insulate at least a portion of the components of the refrigeration circuit, such as a removably attached compressor and condenser. As an example, in some embodiments, the refrigeration system described herein may include an air ram chamber structure fixed to or otherwise enclosing the compressor-condenser assembly. In particular, an exemplary compressor-condenser assembly may be located on the top surface of the air-conditioned space (e.g., on the outer surface of the housing defining the air-conditioned space), and the air ram chamber structure may be attached to the top surface of the air-conditioned space such that the compressor-condenser assembly is arranged therein. Heat dissipation from the compressor-condenser assembly may be exhausted to the external environment of the air ram chamber, which is further thermally insulated from the surrounding environment of the air-conditioned space. In other words, the surrounding environment of the air-conditioned space can refer to the occupancy or interior of the structure in which the refrigeration system operates, such that the external environment of the thermal isolation of the air blast chamber structure can refer to the environment outside the occupancy (e.g., the outside world).

[0070] In other embodiments, as described herein, the compressor-condenser assembly can be positioned on the outer surface of the structure in which the refrigeration system is mounted (e.g., on the outer wall of the structure in the external environment). For example, in an operating configuration where the refrigeration system is mounted in a structure (e.g., a kitchen, etc.), the compressor-condenser assembly can be thermally isolated from the air-conditioned space by at least a portion of the structure. In other words, the outer wall of the structure can support the air-conditioned space (e.g., the interior of a split walk-in refrigeration system) inside the structure, while the compressor-condenser assembly is supported by the exterior of the structure. Specification 6 / 15 pages 12 CN 121039451 A In doing so, embodiments of this disclosure can operate to eliminate or otherwise reduce the thermal burden (e.g., heat dissipation) generated by the operation of the compressor-condenser assembly, which is typically experienced by the occupancy or interior of the structure.

[0071] Definitions

[0072] Examples of this disclosure can now be illustrated more fully with reference to the accompanying drawings, which show some, but not all, examples of this disclosure. In fact, this disclosure may be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these examples are provided so that this disclosure may meet applicable legal requirements. Similar figures refer to similar elements throughout the text.

[0073] It should be understood that the term "communicably interconnected" as used herein encompasses components that are integrally formed with each other or separately formed and interconnected, for example, to allow the flow of refrigerant and / or heat.Furthermore, "communicable connection" encompasses components that are directly formed with each other, or components formed with one or more components located between components that are communicatively connected. Furthermore, "communicable connection" encompasses components that are separable from each other, or components that are permanently connected together. Furthermore, communicatively connected components encompass components that, when disconnected, maintain at least some degrees of freedom of movement in one or more directions or can rotate about an axis (e.g., rotary connection, pivot connection), while when connected, the components may be restricted or unable to move in one or more directions.

[0074] Given the nature of the refrigeration operation described herein, the term "communicable connection" as used herein may refer to fluid communication between components, devices, etc., that form a refrigeration circuit or are otherwise detachably attached to a refrigeration circuit. Therefore, this disclosure contemplates that the components described herein (e.g., compressors, condensers, evaporators, suction lines, capillaries, etc.) can utilize any conduit, channel, piping system, line assembly, and / or the like through which fluid can flow. Similarly, connections between these components, such as those established via disconnect fittings (e.g., double-stop quick-disconnect fittings, etc.), can also be configured to establish fluid connectivity that prevents or otherwise minimizes refrigerant leakage therein.

[0075] As used herein, the phrase “air-conditioned space” or “temperature-controlled space” is a broad term that should be given its common and customary meaning (and not limited to a particular or custom meaning) by those skilled in the art, and refers to, but not limited to, any implementation that at least partially controls, manages, or otherwise influences the thermal condition of an area. As an example, the refrigeration system described herein may include or otherwise define an air-conditioned space in which objects (e.g., food, etc.) may be positioned, wherein the temperature of the air-conditioned space is controlled by components of the refrigeration system. As an example, the refrigeration system described herein may be a split-type refrigeration system operating as a walk-in refrigeration unit. Although the refrigeration system described herein is by reference to defining an air-conditioned space, this disclosure contemplates that the embodiments described herein can be applied to any space where the temperature is controlled.

[0076] As used herein, “thermally connected” or “in thermal connectivity” encompasses components that are directly or indirectly connected to facilitate heat transfer between components. The heat transfer encompasses any type of heat transfer, including radiation, conduction, convection, phase change, etc. Furthermore, "thermal connection" encompasses a component whose temperature change affects the temperature of another component. Additionally, "thermal connection" encompasses any connection, link, or connection between components (e.g., any component through which heat is transferred) that allows heat to be transferred from one component to another.

[0077] As used herein, the terms "thermal isolation," "thermal barrier," and "thermal insulation" refer to components where heat transfer, relative thermal load, etc., between components is eliminated or otherwise reduced.As an example, in some implementations, thermally isolated components may be physically removed from each other or otherwise distanced from each other, such that the heat and associated temperature of one thermally isolated component has little effect on the heat and associated temperature of another thermally isolated component. As described herein, such as with reference to an exemplary air ram chamber structure, thermal isolation may not require physical separation of components. For example, in such an implementation, thermal isolation may refer to components that are thermally connected but whose heat load and / or heat exchange is reduced. In other words, thermal isolation between thermally connected components may refer to the dissipation of heat associated with one or more thermally connected components in order to reduce the heat load of another component in the thermally connected components or the associated environment.

[0078] As used herein, “surrounding environment” of an air-conditioned space refers to the environment adjacent to the exterior of the air-conditioned space. As an example, the refrigeration system described herein may be a walk-in refrigeration unit installed inside a building or other structure, such as a kitchen. In such exemplary embodiments, the surrounding environment can refer to the interior or occupancy of the building or structure whose temperature is not maintained by the refrigeration system (e.g., the occupancy may be air-conditioned but separate from the refrigeration system described herein). The embodiments described herein can thermally insulate various components of the refrigeration circuit to reduce the thermal load on the occupancy or interior of these buildings or structures (e.g., the exemplary surrounding environment).

[0079] As used herein, “external environment” can refer to an environment that is in fluid communication with the interior of the air ram chamber structure described below but is also thermally isolated from the surrounding environment of the air-conditioned space. For example, the air ram chamber structure described herein may include various conditions, passages, etc., through which heat dissipation from the compressor-condenser assembly can be directed to the external environment outside the structure in which the refrigeration system is installed. In other words, the external embodiment of the air ram chamber structure described herein can refer to any location that is thermally isolated from or otherwise separated from the occupancy or interior of the structure (e.g., the surrounding environment of the air-conditioned space).

[0080] As used herein, the term “fluid” includes gases, liquids, and combinations of gaseous and liquid media, unless specifically specified as limited to a particular medium.

[0081] As used herein, the terms “quick disconnection device,” “quick connection device,” “quick disconnect,” “quick connection,” “quick disconnect coupling,” “quick disconnect assembly,” “disconnect assembly,” “multi-line quick disconnection device,” or “multi-line quick disconnect” (hereinafter referred to as “QD,” “QDC,” or the plural forms thereof) are broad terms and should be given their common and customary meanings (and not limited to special or custom meanings) by those skilled in the art, and refer to, but not limited to, snap-fit ​​(ball latch), non-latch, single-stop, double-stop, or dry-stop couplings that can be operated with one or two hands.In one example, the quick-disconnect assembly of this disclosure includes shut-off valves at both internal and external ends to maintain pressure in fluidly connected components via the quick-disconnect assembly. As an example, the quick-disconnect assembly described herein can be used as an attachment mechanism for an exemplary compressor-condenser assembly such that pressure is maintained within a fluid line in fluid communication (e.g., communicatively connected) with the compressor-condenser assembly.

[0082] The phrase “far side” as used herein is a broad term and should be given its common and customary meaning (and not limited to a specific or customary meaning) by those skilled in the art, and refers to, but not limited to, spatial relationships between various elements, such as the opposite “proximal side” reference point, compared to a particular reference point.

[0083] The term “connected” as used herein is a broad term and should be given its common and customary meaning (and not limited to a specific or customary meaning) by those skilled in the art, and refers to, but not limited to, two or more system elements or components constructed to be attached electrically, mechanically, thermally, fluidly, operatively, or otherwise. Similarly, the phrases “operably connected,” “operably linked,” and “operably coupled” as used herein can refer to one or more components linked to another component in a manner that facilitates the transmission of fluid, heat, current, or electrical signals between the components. In some embodiments, the components are part of the same structure and / or integrated with each other (e.g., “directly connected”). In other examples, the components are connected remotely. For example, one or more temperature probes can be used to detect the temperature at different locations and convert that information into a signal; the signal can then be transmitted to electronic circuitry. In this example, the temperature probe is “operably linked” to the electronic circuitry.

[0084] The term “detachably linked” as used herein can refer to two or more system components or parts that are constructed to be or have been electrically, mechanically, thermally, fluidly, operably, chemically, or otherwise attached and detached without damaging the connected elements or components. For example, one or more fluid lines can be detachably connected using a quick-disconnect fitting as described herein. In such an example, the fluid lines are “communicably connected” (e.g., fluidly connected to each other). As used herein, the phrase "permanently connected" can refer to two or more system components or parts that are configured to be or have been electrically, mechanically, thermally, fluidly, operablely, chemically, or otherwise attached, but cannot be disconnected without damaging at least one of the connected components or parts. As described below, at least a portion of the components of a refrigeration system can be detachably connected via quick-disconnect fittings.As an example, the compressor-condenser assembly can be configured to be detachably connected to the refrigeration circuit of the refrigeration system (e.g., via a quick-disconnect fitting), allowing the compressor-condenser assembly to be installed in the field (e.g., at the installation site of the refrigeration system) while maintaining the charge of refrigerant within the system (e.g., within the combined compressor-condenser and refrigeration circuit). In some embodiments, the term "reversibly connected" may be used interchangeably with "detachably connected." Additionally or alternatively, in some embodiments, the term "reversibly connected" may be used to refer to the ability to reverse the flow direction within the refrigeration circuit based on the connection between components.

[0085] Exemplary Refrigeration Systems

[0086] As described herein, embodiments of this disclosure relate to refrigeration systems using refrigerants or A3-class refrigerants, such as refrigeration systems for refrigeration systems, walk-in refrigeration implementations, and / or the like (according to the safety standards of UL60335-2-89 flammable refrigerants, etc.). In one example, the A3 refrigerant is R290 (i.e., propane), an ultra-low GWP (Global Warming Potential) refrigerant that reduces both energy consumption and global warming when used in a refrigeration system. Given that R290 is classified as a flammable refrigerant, the amount of refrigerant that can be safely used in a refrigeration circuit is limited (e.g., according to applicable regulations). In the United States, for example, the current charge limit for R290 is 150 grams (5.3 ounces) per compressor (without leak detection and venting). In other words, an exemplary refrigeration system may include 150 grams (5.3 ounces) of R290 refrigerant without necessarily employing an expensive leak detection and venting system. This charge limit typically limits the refrigeration capacity of systems using R290 as a refrigerant. Therefore, for refrigeration systems using R290 as a refrigerant, it is necessary to increase the refrigeration capacity of said system without increasing the refrigerant charge.

[0087] In some embodiments, the refrigeration systems described herein may utilize capillary tubes for expansion devices. In one example, the refrigeration system of this disclosure is configured to minimize the liquid line, or any device exiting the condenser outlet and entering a conventional expansion valve. By minimizing the liquid line, the charge in the condenser and evaporator is increased. In other words, the refrigeration circuit of the system described herein may include suction lines and capillaries that act as at least a portion of the liquid line in order to minimize the size (e.g., length, etc.) of the liquid line. In doing so, these systems can operate with a top-mounted condenser to minimize volumetric capacity, provided that no leaks are detected and venting is performed as described above, and without exceeding the maximum permissible R290.

[0088] Figure 1 provides a block diagram illustrating a refrigeration system 100 according to an example of this disclosure. The refrigeration system 100 is configured for a refrigeration unit, such as a walk-in refrigeration unit.As used herein, "refrigeration unit" can refer to any refrigeration device or appliance configured to maintain a temperature-controlled environment within an internal storage space or compartment (e.g., an air-conditioned space). In the example, the internal storage space is separated from the external space via a wall or barrier 120, wherein one or more components of the refrigeration system 100 are configured to be separated by the barrier 120 as described in more detail with respect to FIG3. In the example, the components of the refrigeration system 100 are integrated into a single self-contained system. FIG1 depicts a power supply 102 connected in series with a controller 104. In the example, the power supply 102 includes any direct current (DC) or alternating current (AC) voltage source (e.g., a generator, battery, fuel cell, etc.) configured to provide power to the components of the refrigeration system 100.

[0089] FIG1 also depicts a compressor 114, collectively referred to as a compressor-condenser assembly, communicatively connected to the input of a condenser 110. The input of condenser 110 leads to an output that is communicatively connected to the input of evaporator 112 (page 9 / 15, CN 121039451 A, specification). The input of evaporator 112 leads to an output that is communicatively connected to compressor 114. Capillary tube 118 is communicatively connected to the output of evaporator 112 at heat exchanger 116. Condenser fan 106 is located near condenser 110, and evaporator fan 108 is located near evaporator 112. Controller 104 and power supply 102 are communicatively connected to compressor 114.

[0090] Typically, refrigeration system 100 includes power supply 102, controller 104, at least one condenser fan 106, at least one evaporator fan 108, a single or shared condenser 110, a single or shared evaporator 112, at least one compressor 114, at least one heat exchanger 116, and at least one capillary tube 118. In one example, power supply 102 includes any direct current (DC) or alternating current (AC) voltage source capable of supplying power to system components 104, 106, 108, 110, 112, 114, 116, and 118. In one example, controller 104 may be any fire-resistant electronic controller configured to provide logic and decisions for system 100. In one example, controller may be configured to activate compressor 114. In some examples, the system of this disclosure may include multiple compressors 114, and therefore may include a controller configured to sequentially activate each compressor 114, for example, to avoid excessive ampere surges caused by simultaneous activation of each compressor 114. For example, controller may be configured to sequentially activate each compressor 114 based on sensed temperature, temperature changes, manual input, or events exceeding or falling below a temperature threshold.

[0091] In the example, refrigeration system 100 is configured to receive refrigerant (not shown). Liquid refrigerant is configured to enter the input of evaporator 112.At least one evaporator fan 108 may be positioned near the evaporator 112 and configured to guide atmospheric air over the evaporator 112, causing the liquid refrigerant to evaporate.

[0092] In one example, the compressor 114 is configured to draw cold, low-pressure gaseous refrigerant from the evaporator 112 into the compressor inlet. In some examples, the compressor 114 draws in the cold refrigerant via a suction line 113 thermally connected to the capillary tube 118. The compressor 114 then increases the temperature and pressure of the refrigerant and outputs the heated refrigerant to the inlet of the condenser 110. In one example, at least one condenser fan 106 is positioned near the condenser 110 and configured to guide atmospheric air over the condenser 110, causing the refrigerant to cool from a gaseous state to a liquid state. The refrigerant then flows from the outlet of the condenser 110 through the capillary tube 118 into the inlet of the evaporator 112 for evaporative cooling. Before reaching the inlet of evaporator 112, the cooled refrigerant in capillary tube 118 is introduced into heat exchanger 116, as described in more detail with respect to FIG. 2. In this example, heat exchanger 116 includes a capillary tube 118 and a suction line 113 in a thermally coupled relationship. In this example, heat exchanger 116 includes a capillary tube 118 and a suction line 113 thermally coupled to a conductive material such as copper, aluminum, stainless steel, and / or combinations thereof. In this example, heat exchanger 116 includes a section of capillary tube 118 and a section of suction line 113 welded together, functioning as heat exchanger 116. The length and / or composition of the solder used for thermally coupling capillary tube 118 and suction line 113 can be determined based on an efficiency threshold or other system parameters. The dimensions of capillary tube 118 (e.g., length, diameter, etc.) can be selected or otherwise determined using techniques known in the art relative to at least one of the compressor 114 specifications, among others.

[0093] In some examples, system 100 includes a plurality of compressors 114 connected to a shared power source. In some examples, system 100 includes a plurality of expansion devices or capillaries 116 connected in parallel between the output of condenser 110 and the input of evaporator 112. Examples of such systems are found in commonly assigned U.S. Patent No. 11,859,885.

[0094] As described herein, refrigeration system 100 may be configured for use in a walk-in refrigeration unit. In one example, a single refrigeration system 100 is sufficient to provide the total cooling capacity of the walk-in refrigeration unit, or alternatively, multiple systems 100 may be installed to provide sufficient cooling capacity. In one example, refrigeration system 100 is configured within a refrigeration unit (e.g., the refrigeration system may include an air-conditioned space) such that condenser 110 and at least one condenser fan 106 are positioned outside the temperature-controlled space or environment (e.g., outside the air-conditioned space).In another example, evaporator 112 and at least one evaporator fan 108 are located inside a temperature-controlled space or environment (e.g., an air-conditioned space). In one example, condenser fan 106 and condenser fan 108 are separated from evaporator 112 and evaporator 108 via a wall or barrier 120.

[0095] As described above, in some examples, system 100 is configured to receive refrigerant with a GWP (Global Warming Potential) value of less than 10. Specifically, system 100 is configured to receive R290 refrigerant (i.e., propane) with a GWP value of 3. In the United States, the current charge limit for R290 is 150 grams (5.3 ounces) per compressor, so system 100 is configured to receive less than 5.3 ounces of R290 refrigerant charge per compressor.

[0096] Figures 2A-2F show detailed views of an example of heat exchanger 116 of refrigeration system 100. In Figure 2A, both capillary tube 118 and suction line 113 are configured to pass through heat exchanger 116. In this example, capillary tube 118 is configured to carry refrigerant from external condenser 110 to internal evaporator 112 in a first direction 202. Suction line 113 is configured to carry refrigerant from internal evaporator 112 to external compressor 114 in a second direction 204, i.e., in the direction opposite to the first flow direction 202. In this example, the pressure drop across capillary tube 118 causes the heated liquid refrigerant to flash into a mixture of gas and liquid. In one example, capillary tube 118 is connected to suction line 113 via heat exchanger 116, and this heat exchange further lowers the temperature of the refrigerant at or near the evaporator inlet, thereby increasing the cooling capacity of the system.

[0097] In one example, at heat exchanger 116, capillary tube 118 and suction line 113 are directly coupled to allow heat transfer between the cold refrigerant in capillary tube 118 and the heated refrigerant in suction line 113. In another example, at heat exchanger 116, capillary tube 118 and suction line 113 are indirectly coupled to allow heat transfer between the cold refrigerant in capillary tube 118 and the heated refrigerant in suction line 113. In some examples, heat exchanger 116 includes portions of capillary tube 118 and suction line 113 that are temporarily or permanently (e.g., by welding, etc.) attached together. The cooled refrigerant and the heated refrigerant flow in opposite directions 202 and 204, thereby increasing the temperature difference between the refrigerants as they leave heat exchanger 116.

[0098] Figures 2B-2E illustrate exemplary configurations of the thermal connection between capillary tube 118 and suction line 113.In Figure 2B, the capillary 118 and the suction line 113 are thermally connected via a single heat-conducting element 117, which includes, but is not limited to, solder, a metal-containing strip, or a physical structure that radiates or inductively transfers heat from the suction line 113 to the capillary 118. In Figure 2C, the capillary 118 and the suction line 113 are thermally connected via two heat-conducting elements 121 and 122. In Figure 2D, the capillary 118 and the suction line 113 are thermally connected via a heat-conducting element 123 comprising an X-shaped cross-section. In Figure 2E, the capillary 118 and the suction line 113 are thermally connected via a capillary 118 wound around the outside or around the suction line 113. In another example, the capillary 118 and the suction line 113 are thermally connected via a capillary 118 wound around the inner side of the outer periphery of the suction line 113. In one example, the thermally conductive material is adjacent to both the suction line 113 and the capillary tube 118, and the thermally insulating material at least partially surrounds the thermally conductive material.

[0099] In one example, the heat exchanger 116 may be a two-tube heat exchanger, a shell-and-tube heat exchanger, a plate heat exchanger, and / or any other suitable construction. For example, FIG2F shows a shell-and-tube heat exchanger 116, which includes a capillary inlet 206, a capillary outlet 208, a suction line inlet 210, a suction line outlet 212, a plurality of tubes 214, and a plurality of baffles 216. Heated refrigerant 204 flows from the suction line inlet 210 through the plurality of tubes 214 and exits the heat exchanger 116 at the suction line outlet 212. Similarly, cooled refrigerant 202 flows out from the capillary inlet 206, passes through and around the plurality of tubes 214, and exits the heat exchanger 116 at the capillary outlet 208. In the example, heat exchanger 116 includes a plurality of baffles 216 configured to introduce turbulence into the cooled refrigerant 202, thereby increasing the temperature difference between refrigerants 202 and 204 as they exit heat exchanger 116.

[0100] FIG3 illustrates a temperature-controlled environment 300 (e.g., a walk-in refrigeration unit including refrigeration system 100) according to an example of the present disclosure. The temperature-controlled environment 300 includes a door or entrance passage 301 and a barrier 120 (e.g., a wall, ceiling, roof, and / or the like). A first set of system components 101 is located inside the temperature-controlled environment 300 and a second set of system components 103 is located outside the temperature-controlled environment 300. As described above, the second set of system components 103 may include a compressor-condenser assembly. In the example, the first set of system components 101 and the second set of system components 103 may form the refrigeration circuit described herein. In the example, to increase the total cooling capacity of the refrigeration system 100, the temperature control environment 300 includes an additional set of system components.In the example, the first set of system components 101 and the second set of system components 103 are connected together via a capillary tube 118 and a suction line 113 as described with respect to FIG. 1. In the example, the capillary tube 118 and the suction line 113 are configured to pass through holes, openings, or channels in the barrier 120.

[0101] Although shown as a generally rectangular air-conditioned space in FIG. 3, this disclosure contemplates that the dimensions (e.g., size and shape) of the air-conditioned space associated with environment 300 can vary based on the intended application of the refrigeration system 100. In one example, the space regulated within the temperature-controlled environment 300 (e.g., the air-conditioned space) can be configured to maintain a temperature at or above the water freezing point (e.g., a temperature to avoid water freezing) at a fixed height or pressure range. In one example, the space regulated within the temperature-controlled environment 300 can be configured to maintain food at or above the water freezing point at a fixed height or pressure range.

[0102] FIG. 4A-4C show detailed views of an example set 101 of system components. In one example, system component group 101 includes a unit cooler or fan coil unit. Figure 4A shows a front view of system component group 101, which includes a front vent 401, a capillary tube 118, and a suction line 113. Figure 4B shows a rear view of system component group 101, which includes an evaporator 112, an evaporator fan 108, a capillary tube 118, and a suction line 113. Figure 4C shows a detailed view of the capillary tube 118 and suction line 113 at various thermal connections to form a heat exchanger 116.

[0103] Figure 4D shows a detailed view of another example group 103 of system components. In this example, system component group 103 includes a compressor 114, a condenser 110, and a compressor fan 106 (e.g., a compressor-condenser assembly). In this example, system component group 103 is connected to system component group 101 via the capillary tube 118 and the suction line 113. The capillary tube 118 is in thermal communication with the suction line, forming a heat exchanger 116. In the example, the system component group 103 also includes a dryer 501 (e.g., a filter dryer, liquid trap, receiver, etc.) configured to dehumidify the system 103. In the example, the system component group 103 also includes a liquid injection valve 503 configured to adjust the flow rate of liquid refrigerant 204 into the compressor 114, thereby cooling the compressor 114 and preventing or reducing overheating of the compressor 114.

[0104] Exemplary Quick-Disconnect Assembly

[0105] Referring to Figures 5A-5B, an exemplary disconnect assembly 505 of the present disclosure is shown. As described above, the first group of system components 101 and the second group of system components 103 can together form the refrigeration circuit described herein.As shown, the compressor-condenser assembly 103 (e.g., a second set of system components) may include a first disconnect fitting 509 connecting the input of compressor 114 to refrigeration circuit 20 and a second disconnect fitting 507 connecting the output of condenser 110 to the refrigeration circuit. In some examples, the input of compressor 114 is communicatively connected to suction line 113 via first disconnect fitting 116. In some embodiments, the output of condenser 110 is communicatively connected to capillary tube 118 via second disconnect fitting 507. As described above, the first quick-disconnect fitting 509 and the second quick-disconnect fitting 507 may include, but are not limited to, any snap-fit ​​type (ball latch), non-latch, single-stop, double-stop, or dry-break connector operable by one or two hands. In one example, the quick-disconnect fitting 505 of this disclosure includes shut-off valves at both internal and external ends to maintain pressure in the fluidly communicating components via the quick-disconnect fitting. In view of this disclosure, it will be apparent to those skilled in the art that the type of fitting defined by the compressor-condenser assembly 103 can be complementary to the type of fitting defined by the capillary tube 118 / suction line 113 (e.g., male-to-female connection scheme).

[0106] As described herein, the quick-disconnect fitting 505 of this disclosure can be used as an attachment mechanism for an exemplary compressor-condenser assembly 103 (e.g., a second set of systems not reduced) such that pressure is maintained in the fluid line in fluid communication with the compressor-condenser assembly (e.g., communicatively connected), and the charge of refrigerant is maintained in the same line. As shown in the figure, refrigeration system 100 can utilize the capillary tube 118 for the expansion device in order to minimize the size (e.g., length, etc.) of the liquid line 124. In doing so, these systems can use a top-mounted condenser to minimize the volumetric capacity without exceeding the maximum amount of R290 allowed by the absence of detected leaks and ventilation as described above. Furthermore, as described below, in some embodiments, the quick-disconnect assembly 505 of this disclosure can be used in conjunction with the thermal isolation characteristics described herein. In other words, the quick-disconnect assembly 505 can be used in conjunction with the air ram chamber structure 600 of FIG. 6A-6B and / or in the structure-based thermal isolation implementation 300 of FIG. 7-8.

[0107] Exemplary Thermal Isolation Implementation

[0108] Referring to FIG. 6A-6B, an exemplary air ram chamber structure 600 for use with the refrigeration system 100 of this disclosure is shown. As described above, in some embodiments, at least a portion of the components forming the refrigeration circuit can be thermally isolated from the surrounding environment of the air-conditioned space (e.g., the bounded interior of environment 300).In some embodiments, as shown in Figures 6A-6B, thermal isolation can refer to components that are thermally connected but whose heat load on the space (e.g., the surrounding environment) and / or heat exchange is reduced. In other words, thermal isolation between thermally connected components can refer to heat dissipation associated with one or more thermally connected components to reduce the heat load on other thermally connected components, such as by reducing the heat load on the interior occupied by the structure or building surrounding the air ram chamber structure.

[0109] As shown, air ram chamber structure 600 can refer to a housing, partial enclosure, and / or the like, in which at least a portion of the compressor-condenser assembly 103 (e.g., a second set of system components) can be located. Thus, air ram chamber structure 600 can include a housing 601 defining an interior space in which the condenser 110 and / or compressor 114 can be located in instances where air ram chamber structure 600 is connected to refrigeration system 100. This disclosure contemplates that the dimensions (e.g., size and / or shape) of the housing 601 (e.g., or other structural elements, components, parts, etc. defining the interior) can vary based on the associated size of the refrigeration system 100 and / or the compressor-condenser assembly 103. As shown in FIG6B, in operation where the air ram chamber structure 600 is coupled to the refrigeration system 100, at least a portion of the condenser 110 and the compressor 114 (e.g., or multiple portions of these assemblies) can extend into the interior of the housing 601 to form the air ram chamber structure 600.

[0110] In some embodiments, as shown in FIG6B, the compressor-condenser assembly 103 is configured to be positioned on the top surface of the air-conditioned space (e.g., on top of the environment 300). In other words, the compressor-condenser assembly 103 can be positioned on the outer surface of the walk-in refrigeration system. In such an embodiment, the air ram chamber structure 600 can be configured to be attached to the top surface in a manner that substantially encloses the compressor-condenser assembly 103. In some embodiments, the air ram chamber structure 600 may be detachably attached to a top surface, such as for allowing, for example, the mounting of components forming the compressor-condenser assembly 103 (e.g., compressor 114 and condenser 110). Continuing with reference to FIG. 6B, the attachment between the air ram chamber structure 600 and the top surface may be configured to substantially seal the compressor-condenser assembly 103 within the air ram chamber structure 600 (e.g., within the interior of housing 601). In other words, the air ram chamber structure may cooperate with the top surface to form an environment in which the compressor-condenser assembly 103 can be positioned. In doing so, heat dissipation from these components, such as heat generated by the performance of the refrigeration cycle, may be at least partially contained within the air ram chamber structure.For example, if the refrigeration system 100 operates as a walk-in system in an exemplary kitchen (e.g., as shown in FIG3), the air ram chamber structure 600 may be operated to prevent heat generated by the compressor-condenser assembly 103 from penetrating into the kitchen (e.g., the surrounding environment), which may be detrimental, harmful, or otherwise unsuitable for such an environment.

[0111] In order to facilitate the dissipation (e.g., heat dissipation) of heat generated by the compressor-condenser assembly 103 (e.g., by similar convection cooling) from the air ram chamber structure 600, as shown in FIG6A-6B, the air ram chamber structure 600 may define at least one ram chamber inlet 602 in fluid communication with the external environment of the air ram chamber structure 600 and at least one ram chamber outlet 604 in fluid communication with the external environment of the air ram chamber structure 600. In the exemplary embodiments shown in Figures 6A-6B, the air ram chamber structure 600 includes a first air ram chamber inlet 602 and a second air ram chamber inlet 606, each of which is in fluid communication with the external environment. Although reference is made herein to the first air ram chamber inlet 602, the second air ram chamber inlet 606, and the ram chamber outlet 604, this disclosure contemplates that, based on the intended application of the refrigeration system 100, the air ram chamber structure 600 may include any number of openings providing fluid communication with the external environment. Furthermore, as shown in Figure 6B, the inlets 602, 606, and the ram chamber outlet 604 may be communicatively connected to the external environment (e.g., in fluid communication with the external environment) via one or more conduits, channels, pipes, line assemblies, and / or the like through which fluid / air can flow. In some embodiments, the temperature within the air ram chamber structure 600 may be higher than the temperature of the external environment.

[0112] In some embodiments, the air ram chamber structure 600 may further include an exhaust fan 608 coupled to at least one ram chamber output 604. In view of this disclosure, it will be apparent to those skilled in the art that the exhaust fan 608 may be configured to force heated air within the air ram chamber structure 600 to the external environment. Although an exemplary exhaust fan 608 has been referenced in this description, this disclosure contemplates that heated air within the air ram chamber structure 600 may be moved to the external environment using any technology or mechanism. Similarly, this disclosure contemplates that the air ram chamber structure 600 may utilize any technology or mechanism to drive cooled (e.g., relatively low temperature) air from the external environment (e.g., via ram inlets 602, 606) into the interior of the air ram chamber structure 600.In doing so, the air ram chamber structure of Figures 6A-6B can thermally isolate at least a portion of the compressor-condenser assembly 103 to reduce the thermal load on these components without affecting the installation location of the refrigeration system 100 (e.g., occupancy or interior of a kitchen, etc.).

[0113] Referring to Figure 7, an exemplary structural installation (e.g., operational configuration) of a refrigeration system 700 with thermal isolation is shown. As described above, in some embodiments, the thermal isolation of this disclosure can be achieved by physically moving or otherwise distancing components such that the heat and associated temperature of one thermally isolated component has little effect on the heat and associated temperature of other thermally isolated components. As shown in Figure 7, for example, in an operational / installation configuration, the refrigeration system 700 can be installed in or otherwise positioned within a structure (e.g., a building, etc.). In such an embodiment, the structure for installing at least a portion of the refrigeration system 700 can be operated to thermally isolate at least a portion of the compressor-condenser assembly 103 (e.g., condenser 110, etc.) from the air-conditioned space and the surrounding environment of the aforementioned air-conditioned space.

[0114] For example, as shown in FIG7, a portion of the structure that operates to thermally insulate components may include an outer wall 701 of the structure. Although the outer wall is described below with reference to it, this disclosure contemplates that any portion of the structure (e.g., floor, roof, ceiling, interior wall, etc.) can operate to thermally insulate one or more components described herein. As shown, the outer wall 701 may define a first surface 703 adjacent to the air-conditioned space. The first surface 703 of the outer wall 701 may refer to an inner surface (e.g., the interior of the structure). The outer wall 701 may also define a second surface 705 opposite to the first surface 703, the second surface 705 being adjacent to at least a portion of the compressor-condenser assembly 103 (e.g., condenser 110). The second surface 705 of the outer wall 701 may refer to an outer surface (e.g., the exterior of the structure).

[0115] Continuing to refer to FIG7, at least a portion of the compressor-condenser assembly 103 (e.g., condenser 110) is arranged in the external environment of the structure adjacent to the second surface 705. For example, during the installation of the refrigeration system 700 at the structure, the condenser 110 can be supported externally to the structure or in the surrounding environment. The condenser 110 may be fluidly connected (e.g., fluidly connected to the refrigeration circuit via one or more fluid line assemblies). To enable the connection between these components, the support structure may define one or more openings 702 configured to receive at least partially the fluid line assemblies. To support the condenser 110 external to the structure, one or more attachment mechanisms 707 (e.g., brackets, etc.) may be used. During operation, heat dissipation (e.g., heat generated by the condenser 3) can be generated by the performance of the refrigeration cycle described herein.By providing the condenser 3 in the external environment of the structure, heat can be dissipated to the external environment of the structure with minimal or no impact on the temperature inside the structure.

[0116] FIG8 shows a transport configuration of the exemplary refrigeration system of FIG7 according to an example of the present disclosure. For example, before installation (e.g., when leaving the factory or production site), the condenser 110 of the compressor-condenser assembly 103 can be placed on top of the refrigeration system 700 (e.g., a walk-in refrigerator). The transport configuration shown in FIG8 may include a quick-disconnect fitting 505 and a fluid line assembly 704 as described above with reference to FIGS. 5A-5B. The fluid line assembly 704 may be pre-connected coiled for transport, such that at the structure, the condenser 110 can be disassembled and repositioned to the external environment outside the structure for installation as described herein.

[0117] It should be understood that although exemplary system configurations are drawn with respect to the figures, these examples are non-limiting. It is conceivable that additional or alternative constructions may be included in the design of the refrigerant circuit, depending specifically on the specifications of the refrigeration system, walk-in refrigeration unit, and / or the like. While certain exemplary examples are illustrated and shown in the accompanying drawings, it is understood that such examples are illustrative only and do not limit the broad disclosure, and that this disclosure is not limited to the specific constructions and configurations shown and illustrated, as various other changes, combinations, omissions, modifications, and substitutions may be made in addition to those set forth in the foregoing paragraphs. Those skilled in the art will understand that various adaptations, modifications, and combinations of the examples just illustrated can be constructed without departing from the scope and spirit of this disclosure. Therefore, it is understood that this disclosure may not be practiced in the way specifically described herein within the scope of the appended claims.

[0118] Furthermore, it will be understood that, where possible, any advantage, feature, function, device, and / or operational aspect of any example of this disclosure described and / or contemplated herein may be combined and / or included in any other example of this disclosure described and / or contemplated herein and / or vice versa. Furthermore, where possible, unless otherwise expressly stated, any term expressed in the singular form herein is also intended to include the plural form and / or vice versa.Instruction Manual Page 15 / 15 21 CN 121039451 A Figure 1 Figure 2A Instruction Manual Figure 1 / 12 Page 22 CN 121039451 A Figure 2B Figure 2C Figure 2D Instruction Manual Figure 2 / 12 Page 23 CN 121039451 A Figure 2E Figure 2F Instruction Manual Figure 3 / 12 Page 24 CN 121039451 A Figure 3 Figure 4A Instruction Manual Figure 4 / 12 Page 25 CN 121039451 A Figure 4B Figure 4C Instruction Manual Figure 5 / 12 Page 26 CN 121039451 A Figure 4D Instruction Manual Figure 6 / 12 Page 27 CN 121039451 A Figure 5A Instruction Manual Figure 7 / 12 Page 28 CN 121039451 A Figure 5B Instruction Manual Figure 8 / 12 Page 29 CN 121039451 A Figure 6A Figure 6B, Figure 6B, Figure 7, Figure 8, Figure 9B, Figure 9C, Figure 121039451 A, Figure 6B, Figure 7C, Figure 8, Figure 9C, Figure 12 ...

Claims

1. A refrigeration system comprising: an air-conditioned space; and a refrigeration circuit configured to receive A3 refrigerant, wherein the refrigeration circuit comprises: a compressor-condenser assembly comprising: a compressor configured to be coupled to the refrigeration circuit; and a condenser configured to be coupled to the refrigeration circuit, wherein at least a portion of the compressor-condenser assembly is thermally isolated from a perimeter environment of the air-conditioned space.

2. The refrigeration system of claim 1, further comprising an air plenum structure configured to thermally isolate the compressor-condenser assembly. the air plenum structure is configured to substantially enclose the compressor-condenser assembly.

3. The refrigeration system of claim 2 wherein, the compressor-condenser assembly is configured to be positioned on a ceiling of the air-conditioned space, and the air plenum structure is configured to be attached to the ceiling.

4. The refrigeration system of any of claims 2-3, wherein, 5. The refrigeration system of claim 4, further comprising an evaporator positioned within the air-conditioned space. the air plenum structure is removably attached to a ceiling of the air-conditioned space.

6. The refrigeration system of any of claims 4-5, wherein, the attachment between the air plenum structure and the ceiling is configured to substantially seal the compressor-condenser assembly within the air plenum structure.

7. The refrigeration system of any of claims 4-6, wherein, the air plenum structure defines:

8. The refrigeration system of any of claims 2-7, wherein, at least one plenum input in fluid communication with an external environment of the air plenum structure; and at least one plenum output in fluid communication with the external environment of the air plenum structure. the external environment of the air plenum structure is thermally isolated from a perimeter environment of the air-conditioned space.

9. The refrigeration system of claim 8, wherein, the air plenum structure defines first and second air plenum inputs that are both in fluid communication with the external environment of the air plenum structure.

10. The refrigeration system of any of claims 8-9, wherein, 11. The refrigeration system of any one of claims 8 to 10, further comprising an exhaust fan coupled to the at least one plenum output, wherein the exhaust fan is configured to drive heated air within the air plenum structure to the external environment. a temperature within the air plenum structure is greater than a temperature of the external environment.

12. The refrigeration system of any of claims 2-11, wherein, in an operational configuration in which the refrigeration system is installed in a structure, the compressor-condenser assembly is thermally isolated from a perimeter environment of the air-conditioned space via at least a portion of the structure.

13. The refrigeration system of claim 1 wherein, the portion of the structure defines:

14. The refrigeration system of claim 13, wherein, a first surface proximate the air-conditioned space; and a second surface, opposite the first surface, proximate the compressor-condenser assembly. the portion of the structure comprises an exterior wall of the structure.

15. The refrigeration system of any of claims 13-14, wherein, the exterior wall defines:

16. The refrigeration system of claim 15, wherein, a first surface proximate the air-conditioned space; and a second surface, opposite the first surface, proximate the compressor-condenser assembly. the compressor-condenser assembly is disposed in an external environment of the structure proximate the second surface.

17. The refrigeration system of claim 16, wherein, a support structure defines one or more openings configured to at least partially receive a fluid line set therein, wherein the fluid line set is configured to provide fluid communication between a compressor-condenser assembly and an air-conditioned space through the structure.

18. The refrigeration system of any of claims 13-17, wherein, ​ 19. The refrigeration system of any of the preceding claims, wherein, The compressor-condenser assembly and the refrigeration circuit include a full charge of the A3 refrigerant.

20. The refrigeration system of any of the preceding claims, wherein, The compressor-condenser assembly further includes: a first disconnect fitting that couples the compressor input to the refrigeration circuit; and a second disconnect fitting that couples the condenser output to the refrigeration circuit.

21. The refrigeration system of claim 20, wherein, At least one of the first disconnect fitting and the second disconnect fitting is a double shut-off quick disconnect fitting.

22. The refrigeration system of claim 1, wherein: The condenser further includes a condenser output communicably coupled to a first end of a capillary tube; and The compressor further includes a compressor input and a compressor output.

23. The refrigeration system of claim 22, further comprising an evaporator including an evaporator input and an evaporator output, wherein the evaporator input is communicably coupled to a second end of the capillary tube and the evaporator output is communicably coupled to a first end of a suction line, wherein at least a portion of the suction line is thermally coupled to at least a portion of the capillary tube.

24. The refrigeration system of any of claims 22-23, wherein, The compressor input is communicably coupled to a second end of the suction line.

25. The refrigeration system of any of claims 22-24, wherein, The compressor output is communicably coupled to the condenser.

26. The refrigeration system of any of claims 23-25, wherein, The portion of the suction line and the portion of the capillary tube are adjacent to or coupled to a heat exchanger.

27. The refrigeration system of any of claims 22-26, wherein, The compressor input is communicably coupled to the suction line via a first disconnect fitting.

28. The refrigeration system of any of claims 21-27, wherein, The condenser output is communicably coupled to the capillary tube.

29. The refrigeration system of any of the preceding claims, further comprising a controller coupled to a power source.

30. The refrigeration system of any of the preceding claims, wherein, The A3 refrigerant has a global warming potential (GWP) value of less than 10.

31. The refrigeration system of any of the preceding claims, wherein, The refrigeration system further includes a maximum charge of 5.3 ounces (150 grams) of the A3 refrigerant per compressor.

32. The refrigeration system of any of the preceding claims, wherein, The A3 refrigerant includes propane.

33. The refrigeration system of any of the preceding claims, wherein, The refrigeration circuit is formed as part of a walk-in refrigeration unit.

34. A refrigeration system configured to receive a refrigerant, the refrigeration system comprising: a condenser including a condenser output communicably coupled to a first end of a capillary tube; and an evaporator including an evaporator input and an evaporator output, wherein the evaporator input is communicably coupled to a second end of the capillary tube and the evaporator output is communicably coupled to a first end of a suction line, wherein at least a portion of the suction line is thermally coupled to at least a portion of the capillary tube.

35. The refrigeration system of claim 34, further comprising a compressor including a compressor input and a compressor output.

36. The refrigeration system of any of claims 34-35, wherein, The compressor input is communicably coupled to a second end of the suction line.

37. The refrigeration system of any of claims 34-36, wherein, The compressor output is communicably coupled to the condenser.

38. The refrigeration system of any of claims 34 to 37, further comprising an air conditioned space, wherein the evaporator is positioned within the air conditioned space and the condenser is positioned outside of the air conditioned space or is physically separated from the evaporator by a structure.

39. The refrigeration system of any of claims 34-38, wherein, The refrigerant has a global warming potential (GWP) value of less than 10.

40. The refrigeration system of any of claims 34-39, wherein, The refrigerant is classified as an A3 refrigerant.

41. The refrigeration system of claim 40, wherein, The refrigeration system further includes a maximum charge of 5.3 ounces of the A3 refrigerant per compressor.

42. The refrigeration system of any of claims 34-41, further comprising a controller coupled to a power source.

43. The refrigeration system of any of claims 34-42, wherein, The refrigerant includes propane.

44. The refrigeration system of any of claims 34-43, wherein, The portion of the suction line and the portion of the capillary tube are adjacent to or coupled to a heat exchanger.

45. A walk-in refrigeration unit comprising: one or more refrigeration systems configured to receive a refrigerant, wherein each refrigeration system comprises: a condenser comprising a condenser output communicably coupled to a first end of a capillary tube; and an evaporator comprising an evaporator input and an evaporator output, wherein the evaporator input is communicably coupled to a second end of the capillary tube and the evaporator output is communicably coupled to a first end of a suction line, wherein at least a portion of the suction line is thermally coupled to at least a portion of the capillary tube.

46. The walk-in refrigeration unit of claim 45, further comprising a compressor comprising a compressor input and a compressor output.

47. The walk-in refrigeration unit of any of claims 45-46, wherein, The compressor input is communicably coupled to a second end of the suction line.

48. The walk-in refrigeration unit of any of claims 45-47, wherein, The compressor output is communicably coupled to the condenser.

49. The walk-in refrigeration unit of any of claims 45-48, further comprising an air conditioned space, wherein the evaporator is positioned within the air conditioned space and the condenser is positioned outside of the air conditioned space or is physically separated from the evaporator by a structure.

50. The walk-in refrigeration unit of any of claims 45-49, wherein, The refrigerant has a global warming potential (GWP) value of less than 10.

51. The walk-in refrigeration unit of any of claims 45-50, wherein, The refrigerant is classified as an A3 refrigerant.

52. The walk-in refrigeration unit of any of claims 45-51, wherein, The one or more refrigeration systems further include a maximum charge of 5.3 ounces of the A3 refrigerant per compressor.

53. The walk-in refrigeration unit of any of claims 45-52, further comprising a controller coupled to a power source.

54. The walk-in refrigeration unit of any of claims 45-53, wherein, The refrigerant includes propane.

55. The walk-in refrigeration unit of any of claims 45-54, wherein, The portion of the suction line and the portion of the capillary tube are adjacent to or coupled to a heat exchanger.

56. A method of cooling a walk-in refrigeration unit, the method comprising: providing one or more refrigeration systems, wherein each refrigeration system comprises: a condenser comprising a condenser output communicably coupled to a first end of a capillary tube; and an evaporator comprising an evaporator input and an evaporator output, wherein the evaporator input is communicably coupled to a second end of the capillary tube and the evaporator output is communicably coupled to a first end of a suction line, wherein at least a portion of the suction line is thermally coupled to at least a portion of the capillary tube.

57. The method of claim 56, wherein, Each refrigeration system further comprises a compressor comprising a compressor input and a compressor output.

58. The method of any one of claims 56-57, wherein, The compressor input is communicably coupled to a second end of the suction line.

59. The method of any one of claims 56-58, wherein, The compressor output is communicably coupled to the condenser.

60. The method of any one of claims 56-59, wherein, The walk-in refrigeration unit also includes an air conditioned space, wherein the evaporator is positioned within the air conditioned space and the condenser is positioned outside of the air conditioned space or physically separated from the evaporator by a structure.

61. The method of any one of claims 56-60, wherein, Each refrigeration system also includes a controller coupled to a power source.

62. The method of any one of claims 56-61, wherein, The portion of the suction line and the portion of the capillary tube are adjacent to or coupled to a heat exchanger.

63. The method of any one of claims 56-62, wherein, Each refrigeration system is configured to receive a refrigerant having a global warming potential (GWP) value of less than 10.

64. The method of any one of claims 56-63, wherein, Each refrigeration system is configured to receive a refrigerant classified as an A3 refrigerant.

65. The method of any one of claims 56-64, wherein, Each refrigeration system also includes a maximum charge of 5.3 ounces of the A3 refrigerant per compressor.

66. The method of any one of claims 56-65, wherein, Each refrigeration system is configured to receive a refrigerant including propane.

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