Temperature-Controlled System with Thermally Isolated Components

This application is a continuation of International Patent Application No. PCT/US25/14513, filed Feb. 4, 2025, which application claims priority to U.S. Provisional Patent Application No. 63/550,024, filed Feb. 5, 2024, and U.S. Provisional Patent Application No. 63/721,071, filed Nov. 15, 2024, the entire contents of which applications are incorporated by reference in their entirety.

The present disclosure relates to refrigeration systems. In particular, the disclosed systems include a conditioned space and refrigeration circuit components (e.g., compressors, condensers, etc.) that are thermally isolated from an ambient environment of the conditioned space and/or whose refrigeration circuit utilize a capillary tube in place of a liquid line thermally coupled to a suction line.

Refrigeration systems (e.g., walk-in refrigerators or the like) and/or the like are used in a variety of environments (e.g., retail environments, kitchens, etc.) to provide refrigerated (e.g., conditioned) spaces for refrigerated goods, such as food goods. The refrigeration system operates to maintain the goods below ambient temperature by the use of cooled air that is circulated around the goods. Below ambient temperature includes at or below 40° F. (4.4° C.) or at or below 0° F. (−17.8° C.), for example, and combinations of both in the same conditioned space. A refrigeration system may include a conditioned space (or storage space) and an opening to permit access to the food goods contained therein, such as via a door. Cooling for the refrigeration system may be provided by heat exchange with a heat absorbing heat exchanger of a refrigeration circuit of a cooling system, such as with an evaporator being the heat absorbing heat exchanger. The refrigerant loop may further include a condenser as a heat rejection heat exchanger.

The following presents a simplified summary of one or more examples of the disclosure in order to provide a basic understanding of such examples. This summary is not an extensive overview of all contemplated examples and is intended to neither identify key or critical elements of all examples, nor delineate 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 description that is presented later.

As described hereinafter, the presently disclosed system utilizes a capillary tube for the expansion device. In one example, the presently disclosed split refrigeration system reduces the dimensions of the liquid line, or any means that leaves the outlet of the condenser and goes to a traditional expansion valve. By minimizing the liquid line, the charge amount in the condenser and the evaporator is increased. Thus, the present disclosure gives the refrigeration system more capacity with the regulated small amount of working refrigerant that is allowed. The presently disclosed system is an improvement over existing systems as no ductwork is added to reduce airflow as in conventional self-contained refrigeration systems.

Further, and as described more fully hereinafter, the embodiments of the present disclosure may operate to thermally isolate at least a portion of the components of the refrigeration circuit, such as the removably attached compressors and condensers. By way of an example, in some embodiments, the refrigeration systems described herein may include an air plenum structure that is secured over or otherwise envelopes a compressor-condenser assembly. In particular, an example compressor-condenser assembly may be positioned at a top surface of the conditioned space (e.g., on an exterior surface of the housing bounding the condition space), and the air plenum structure may be attached to the top surface of the conditioned space such that the compressor-condenser assembly is disposed therein. The heated rejection of the compressor-condenser assembly may be exhausted to an external environment of the air plenum that is further thermally isolated from the ambient environment of the conditioned space. In other words, the ambient environment of the conditioned space may refer to the occupancy or interior of a structure within which the refrigeration system operates, such that the thermally isolated external environment of the air plenum structure may refer to an environment that is external to this occupancy (e.g., outside).

In some examples, a refrigeration system is provided. The refrigeration system may include a conditioned space and a refrigeration circuit configured to receive an A3 refrigerant. The refrigeration circuit may include a compressor-condenser assembly including 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 isolated from an ambient environment of the conditioned space.

In some aspects, alone or in combination with any of the previous aspects, the refrigeration system may include an air plenum structure configured to thermally isolate the compressor-condenser assembly.

In some aspects, alone or in combination with any of the previous aspects, the air plenum structure may be configured to substantially envelop the compressor-condenser assembly.

In some aspects, alone or in combination with any of the previous aspects, the compressor-condenser assembly may be configured to be positioned at a top surface of the conditioned space, and the air plenum structure may be configured to be attached to the top surface.

In some aspects, alone or in combination with any of the previous aspects, the refrigeration system may further include an evaporator configured to be positioned within the conditioned space.

In some aspects, alone or in combination with any of the previous aspects, the air plenum structure may be removably attached to the top surface of the conditioned space.

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

In some aspects, alone or in combination with any of the previous aspects, the air plenum structure may define 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.

In some aspects, alone or in combination with any of the previous aspects, the air plenum structure may define a first air plenum input and a second air plenum input each of which are in fluid communication with the external environment of the air plenum structure.

In some aspects, alone or in combination with any of the previous aspects, the external environment of the air plenum structure may be thermally isolated from the ambient environment of the conditioned space.

In some aspects, alone or in combination with any of the previous aspects, the refrigeration system may further include an exhaust fan coupled to the at least one plenum output. The exhaust fan may be configured to force heated air within the air plenum structure to the external environment.

In some aspects, alone or in combination with any of the previous aspects, a temperature within the air plenum may be greater than a temperature of the external environment.

Additionally or alternatively, in some aspects, alone or in combination with any of the previous aspects, in an operational configuration in which the refrigeration system is installed in a structure, the compressor-condenser assembly may be thermally isolated from the ambient environment of the conditioned space via at least a portion of the structure.

In some aspects, alone or in combination with any of the previous aspects, the portion of the structure may define a first surface proximate the conditioned space and a second surface opposite the first surface proximate the compressor-condenser assembly.

In some aspects, alone or in combination with any of the previous aspects, the portion of the structure may include an exterior wall of the structure.

In some aspects, alone or in combination with any of the previous aspects, the exterior wall may define a first surface proximate the conditioned space and a second surface opposite the first surface proximate the compressor-condenser assembly.

In some aspects, alone or in combination with any of the previous aspects, the compressor-condenser assembly may be disposed in an external environment of the structure proximate the second surface.

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

In some aspects, alone or in combination with any of the previous aspects, the compressor-condenser assembly and the refrigeration circuit may include a full charge of the A3 refrigerant.

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

In some aspects, alone or in combination with any of the previous aspects, at least one of the first and the second disconnect fittings may be a double shut-off quick disconnect fitting.

In some aspects, alone or in combination with any of the previous aspects, the condenser may further include a condenser output communicably coupled to a first end of a capillary tube, and the compressor may further include a compressor input and a compressor output.

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

In some aspects, alone or in combination with any of the previous aspects, the compressor input may be communicably coupled to a second end of the suction line.

In some aspects, alone or in combination with any of the previous aspects, the compressor output may be communicably coupled to the condenser.

In some aspects, alone or in combination with any of the previous aspects, the portion of the suction line and the portion of the capillary tube may be adjacent or coupled to a heat exchanger.

In some aspects, alone or in combination with any of the previous aspects, the compressor input may be communicably coupled to the suction line via a first disconnect fitting.

In some aspects, alone or in combination with any of the previous aspects, the condenser output may be communicably coupled to the capillary tube.

In some aspects, alone or in combination with any of the previous aspects, the refrigeration system may further include a controller coupled to a source of power.

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

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

In some aspects, alone or in combination with any of the previous aspects, the A3 refrigerant may include propane.

In some examples, a refrigeration system is provided. The refrigeration system is configured to receive a refrigerant and includes: 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 and at least a portion of the capillary tube are thermally coupled.

In some aspects, alone or in combination with any of the previous aspects, the refrigeration circuit includes a compressor comprising a compressor input and a compressor output. In one aspect, alone or in combination with any of the previous aspects, the compressor input is communicably coupled to a second end of the suction line. In one aspect, alone or in combination with any of the previous aspects, the compressor output is communicably coupled to the condenser.

In some aspects, alone or in combination with any of the previous aspects, the refrigeration system further includes a conditioned space, wherein the evaporator is positioned within the conditioned space and the condenser is either positioned exterior to the conditioned space or physically separated from the evaporator by a structure.

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

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

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 a refrigerant, wherein each refrigeration system includes: 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 and at least a portion of the capillary tube are thermally coupled.

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 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 and at least a portion of the capillary tube are thermally coupled.

In some examples, a refrigeration system is provided. The refrigeration system is configured to receive a refrigerant and includes: 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 and at least a portion of the capillary tube are thermally coupled.

In some aspects, alone or in combination with any of the previous aspects, the refrigeration circuit includes a compressor comprising a compressor input and a compressor output. In one aspect, alone or in combination with any of the previous aspects, the compressor input is communicably coupled to a second end of the suction line. In one aspect, alone or in combination with any of the previous aspects, the compressor output is communicably coupled to the condenser.

In some aspects, alone or in combination with any of the previous aspects, the refrigeration system further includes a conditioned space, wherein the evaporator is positioned within the conditioned space and the condenser is either positioned exterior to the conditioned space or physically separated from the evaporator by a structure.

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

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