TEMPERATURE-CONTROLLED CABINET WITH QUICK-CONNECT COMPRESSOR-CONDENSER ASSEMBLY

Abstract

Disclosed and described here are example temperature-controlled display cabinets having an interior conditioned space and a refrigeration circuit communicably coupled to a controller and charged with a refrigerant. The refrigeration circuit includes a compressor-condenser assembly removably coupled to the refrigeration circuit and/or temperature-controlled display cabinet. An evaporator is operably coupled to the refrigeration circuit, the evaporator is positioned at a bottom surface of the temperature-controlled display cabinet, and the compressor-condenser assembly is removably coupled to a top surface of the temperature-controlled display cabinet. Methods of installing temperature-controlled display cabinet with a charge of A3 refrigerant utilize disconnect fittings coupling the compressor-condenser assembly with the refrigeration circuit are further disclosed.

Claims

1. A refrigeration system comprising: a display cabinet comprising a conditioned space; and a refrigeration circuit configured to receive an A3 refrigerant, wherein the refrigeration circuit comprises: a compressor-condenser assembly comprising: a compressor comprising a compressor input and a first disconnect fitting coupling the compressor input to the refrigeration circuit; and a condenser comprising a condenser output and a second disconnect fitting coupling the condenser output to the refrigeration circuit; wherein the compressor-condenser assembly is configured to be removably coupled to the refrigeration circuit.

2. The refrigeration system of claim 1, wherein the compressor-condenser assembly and the refrigeration circuit comprise a full charge of the A3 refrigerant.

3. The refrigeration system of claim 1, wherein the compressor-condenser assembly is removably coupled to the display cabinet.

4. The refrigeration system of claim 1, wherein at least one of the first and the second disconnect fittings is a double shut-off quick disconnect fitting.

5. The refrigeration system of claim 4, wherein the first and the second disconnect fittings are double shut-off quick disconnect fittings.

6. The refrigeration system of claim 1, wherein the refrigeration circuit further comprises a suction line and a capillary tube configured to minimize a dimension of a liquid line.

7. The refrigeration system of claim 6, wherein the compressor input is communicably coupled to the suction line via the first disconnect fitting.

8. The refrigeration system of any one of claim 6, wherein the condenser output is communicably coupled to the capillary tube.

9. The refrigeration system of claim 1, further comprising at least one evaporator.

10. The refrigeration system of claim 9, wherein the evaporator is configured to be positioned at a bottom surface of the display cabinet.

11. The refrigeration system of claim 10, wherein the compressor-condenser assembly is configured to be positioned at a top surface of the display cabinet opposite the bottom surface.

12. The refrigeration system of claim 9, wherein the compressor-condenser assembly is configured to be positioned at a top surface of the display cabinet, and the evaporator is configured to be positioned at a bottom surface of the display cabinet opposite the top surface.

13. The refrigeration system of any one of claim 6, wherein at least a portion of the suction line and at least a portion of the capillary tube are thermally coupled.

14. The refrigeration system of claim 13, wherein the portion of the suction line and the portion of the capillary tube are adjacent to or coupled to a heat exchanger.

15. The refrigeration system of claim 9, wherein the evaporator is positioned within the conditioned space and the condenser is positioned exterior to the conditioned space.

16. The refrigeration system claim 1, wherein the A3 refrigerant has a Global Warming Potential (GWP) value less than 10.

17. The refrigeration system of claim 1, wherein the refrigeration system further comprises a maximum charge of 5.3 ounces (150 grams) of the A3 refrigerant per compressor.

18. The refrigeration system of claim 1, wherein the A3 refrigerant comprises propane.

19. A temperature controlled display cabinet comprising: a conditioned space configured for temperature control; and at least a portion of a refrigeration circuit containing a charge of an A3 refrigerant, the refrigeration circuit comprising: a suction line having a first end and a second end; a first disconnect fitting coupled to the first end of the suction line, the first disconnect fitting configured to operably couple to a compressor input; a capillary tube having a first end and a second end; and a second disconnect fitting coupled to the first end of the capillary tube, the second disconnect fitting configured to operably couple to a condenser output.

20. The temperature controlled display cabinet of claim 19, wherein the temperature controlled display cabinet is configured to operably couple to a compressor-condenser assembly, the compressor-condenser assembly comprising: a compressor comprising the compressor input; and a condenser comprising the condenser output.

21. The temperature controlled display cabinet of claim 19, wherein the compressor-condenser assembly is configured to be coupled to the display cabinet and the refrigeration circuit.

22. The temperature controlled display cabinet of claim 19, wherein the A3 refrigerant comprises a maximum charge of 5.3 ounces (150 grams) per compressor.

23. The temperature controlled display cabinet of claim 19, wherein the refrigerant comprises propane.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Having described certain example embodiments of the present disclosure in general terms above, reference will now be made to the accompanying drawings. The components illustrated in the figures may or may not be present in certain embodiments described herein. Some embodiments may include fewer (or more) components than those shown in the figures.

[0054] FIGS. 1A-1B illustrate a refrigeration system, in accordance with examples of the present disclosure;

[0055] FIGS. 2A-2B are block diagrams illustrating a refrigeration circuit for a refrigeration system, in accordance with examples of the present disclosure;

[0056] FIG. 3 is a block diagram illustrating components of a refrigeration circuit, in accordance with an example of the present disclosure;

[0057] FIGS. 4A-4B illustrate an aerial perspective of an interior of a display cabinet, in accordance with an example of the present disclosure; and

[0058] FIGS. 5A-5B illustrate example quick disconnect fittings, in accordance with an example of the present disclosure.

DETAILED DESCRIPTION

Overview

[0059] Embodiments of the present disclosure are directed to a refrigeration system for a temperature-controlled display cabinet or conditioned space. A temperature-controlled display cabinet or an endless row of such cabinets is configured to use an A3 classified refrigerant while maximizing the available display area of the cabinet. The presently disclosed display cabinet provides for maximizing conditioned space in the cabinet by allowing the condenser unit to be top-mounted. In one example, the presently disclosed display cabinet provides for the top-mounted condenser unit to be removably disconnected/connected from the refrigeration loop for installation. The presently disclosed display cabinet, via the readily disconnectable top-mounted condenser unit with a full charge of A3 refrigerant, provides for reassembly with the refrigeration circuit without significant loss of the A3 refrigerant. Such display units may be provided in an endless row as desired using 150 grams of A3 refrigerant without the need for a leak detection system.

[0060] The present disclosure is directed to refrigeration systems that use A3 classified refrigerants (according to the UL60335-2-89), such as R290 (i.e., propane). In a setting in which multiple temperature-controlled cabinets are positioned together, such as adjacently along an aisle of a store, each temperature-controlled cabinet using an A3 classified refrigerant is provided with an individual condenser unit. In one example, each temperature-controlled cabinet using an A3 classified refrigerant is provided with an individual condenser unit that is connected with a quick-release connector so as to enable the removable connections described herein.

[0061] The presently disclosed system, in one example, includes a condenser configured to be positioned at the top of a display cabinet, where the condenser is removably coupled to a refrigeration circuit. In one example, a plurality of condensers are positioned at the top of a display cabinet, where the condensers are removably coupled to a refrigeration circuit using quick disconnects (e.g., quick disconnect fittings or the like as defined herein). In one example, the presently disclosed system includes one or more evaporator units positioned at a bottom surface of the display cabinet in order to maximize the available display area of the cabinet (e.g., maximize the dimensions of the conditioned space).

[0062] In one example, the presently disclosed system includes a plurality of condensers positioned at the top of a display cabinet, in combination with one or more evaporator units positioned at a bottom surface of the display cabinet, where the condensers and evaporators are coupled to at least one refrigeration circuit. In one example, the presently disclosed system includes a plurality of condensers positioned at the top of a plurality of display cabinets, in combination with one or more evaporator units positioned at a bottom surface of the plurality of display cabinets, where each of the plurality of display cabinets comprises at least one refrigeration circuit. In one example, the presently disclosed system includes a plurality of condensers positioned at the top of a plurality of display cabinets, in combination with one or more evaporator units positioned at a bottom surface of the plurality of display cabinets, where each of the plurality of display cabinets comprises a single refrigeration circuit.

[0063] The present disclosure also provides for a refrigeration system that includes a standalone refrigeration circuit for each display cabinet of a plurality of display cabinets. In one example, the presently disclosed system includes a plurality of condensers positioned at the top of a display cabinet, where the condensers are coupled to a refrigeration circuit using quick disconnects (e.g., quick disconnect fittings or the like), in combination with one or more evaporator units positioned at a bottom surface of the display cabinet. In such a configuration, the available display area of the cabinet (e.g., the dimensioned of the conditioned space) is maximized.

Definitions

[0064] Examples of the present disclosure now may be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, examples of the disclosure are shown. Indeed, the 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 satisfy applicable legal requirements. Like numbers refer to like elements throughout.

[0065] It should be understood that communicably coupled, as used herein, encompasses components that are formed integrally with each other, or are formed separately and coupled together, for example, to allow the flow of refrigerant and/or heat. Furthermore, communicably coupled encompasses components that are formed directly to each other, or to each other with one or more components located between the components that are communicably coupled together. Furthermore, communicably coupled encompasses components that are detachable from each other, or that are permanently coupled together. Furthermore, communicably coupled components encompasses components that retain at least some freedom of movement in one or more directions or may be rotated about an axis (e.g., rotationally coupled, pivotally coupled) when disconnected, whereas when connected, restricted or no movement in one or more directions of the components can occur. Given the nature of the refrigeration operations described herein, the terms communicably coupled as used herein may refer to the fluid communication between the components, devices, etc. forming or otherwise removably attached with the refrigeration circuits. As such, the present disclosure contemplates that the components described herein (e.g., the compressor, the condenser, the evaporator, the suction line, the capillary tube, etc.) may leverage any conduit, channel, tubing, and/or the like through which a fluid may flow. Similarly, the connections between these components, such as those that are established via disconnect fittings (e.g., double shut-off quick disconnect fittings or the like), may also be configured to establish fluid communication that prevents or otherwise minimizes the leakage of the refrigerants therein.

[0066] As used herein, the phrase refrigerated display cabinet is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art (and is not to be limited to a special or customized meaning) and refers without limitation to any implementation that at least partially controls, manages, or otherwise impacts the thermal condition of an area (e.g., a conditioned space). By way of example, a refrigerated display cabinet as described herein may include or otherwise define a conditioned space within which objects (e.g., food items or the like) may be positioned where the temperature of the conditioned space is controlled by the components of the refrigerated display cabinet. Such a display cabinet may further include any mechanism, structure, etc. for viewing (e.g., by a user) the interior of the conditioned space, such as via a glass door or other transparent portion of the refrigerated display cabinet.

[0067] Thermally coupled or in thermal communication as used herein encompasses components that are directly or indirectly coupled so as to facilitate heat transfer between the components. Said heat transfer encompasses any type of heat transfer including radiation, conduction, convection, phase changes, and the like. Furthermore, thermally coupled encompasses components where a temperature change of one component affects a temperature of another component. Furthermore, thermally coupled encompasses any connection, coupling, link, or the like between components such that heat from one component is imparted to another component (e.g., any components between which heat is transferred).

[0068] Ambient environment as used herein refers to a non-air-conditioned environment or non-temperature-regulated environment. Examples of a non-air-conditioned ambient environment include the outside/outdoors, or structures existing in the outdoors that are without a heating/cooling systems, e.g., barns, sheds, storage units and the like. Ambient temperature as used herein is an air temperature of the non-temperature-regulated ambient environment. By way of a particular example, the ambient environment may refer to any area outside of the conditioned space of an example refrigerated display cabinet.

[0069] As used herein, the term fluid is inclusive of gaseous, liquid, and combinations of gas and liquid medium unless specifically designated as limited to a particular medium.

[0070] As used herein, the terms quick-disconnector, quick connectors, quick-disconnect, quick connect, quick release couplings, quick disconnect fittings, disconnect fittings, multiple line quick disconnector, or multiple line quick disconnect, (hereinafter referred to as QD, QDC or their plural forms) are broad terms, and are to be given their ordinary and customary meaning to a person of ordinary skill in the art (and is not to be limited to a special or customized meaning), and refers without limitation to snap type (ball latching), non-latching, single shut-off, double shut-off, or dry break couplings operable by one or two hands. In one example, the quick disconnect fittings of the present disclosure include shut-off valves within both the internal and external ends so as to retain pressure in the components in fluid communication via the quick disconnect fittings. By way of example, quick disconnect fittings described herein may be used as an attachment mechanism for an example compressor-condenser assembly such that the pressure within the fluid lines in fluid communication with (e.g., communicably coupled with) the compressor-condenser assembly is maintained.

[0071] The phrase distal to as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art (and is not to be limited to a special or customized meaning) and refers without limitation to the spatial relationship between various elements in comparison to a particular point of reference, such as opposite a proximal to reference.

[0072] The term coupled as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art (and is not to be limited to a special or customized meaning) and refers without limitation to two or more system elements or components that are configured to be at least one of electrically, mechanically, thermally, fluidically, operably, or otherwise attached. Similarly, the phrases operably connected, operably linked, and operably coupled as used herein may refer to one or more components linked to another component(s) in a manner that facilitates transmission of fluid, heat, current, or electrical signals between the components. In some examples, components are part of the same structure and/or integral with one another (e.g., directly coupled). In other examples, components are connected via remote means. For example, one or more temperature probes may be used to detect temperatures at different locations and convert that information into a signal; the signal may then be transmitted to an electronic circuit. In this example, the temperature probe is operably linked to the electronic circuit.

[0073] The terms removably coupled as used herein may refer to two or more system elements or components that are configured to be or have been electrically, mechanically, thermally, fluidically, operably, chemically, or otherwise attached and detached without damaging the coupled elements or components. For example, one or more fluid lines may be removably coupled with quick disconnect fittings as described herein. In such an example, the fluid lines are communicably coupled (e.g., in fluid communication with one another). The phrase permanently coupled as used herein may refer to two or more system elements or components that are configured to be or have been electrically, mechanically, thermally, fluidically, operably, chemically, or otherwise attached but cannot be uncoupled without damaging at least one of the coupled elements or components. As described hereinafter, at least a portion of the components of the refrigeration system may be removably coupled via quick disconnect fittings. By way of example, a compressor-condenser assembly may be configured to be removable coupled with a refrigeration circuit of a refrigerated display cabinet (e.g., by quick disconnect fittings), such that the compressor-condenser assembly may be installed on site (e.g., at the installation of the refrigerated display cabinet) while maintaining a charge of refrigerant within the system (e.g., within the combined compressor-condenser and refrigeration circuit). In some embodiments, the terms reversibly coupled may be used interchangeably with removably coupled. Additionally or alternatively, in some embodiments, the terms reversibly coupled may be used to refer to the ability for the flow direction within the refrigeration circuit to be reversed based on the connection between the components.

Example Refrigeration Systems

[0074] As described herein, embodiments of the present disclosure are directed to refrigeration systems that use refrigerants or A3 classified refrigerants, such as those used in display cabinet based refrigeration implementations (according to the UL60335-2-89 standard for safety with flammable refrigerants or the like). In one example, the A3 refrigerant is R290 (i.e., propane), which is an ultra-low GWP (Global Warming Potential) refrigerant that, when used in refrigeration systems, both lowers the energy consumed and reduces global warming. Given that R290 is classified as a flammable refrigerant, the amount of refrigerant that may be safely used in a refrigeration circuit is limited (e.g., by applicable regulations). In the United States, for example, the current charge limit for R290 is 150 gm (5.3 oz) per compressor (without leakage detection and ventilation). Said differently, an example refrigeration system may include 150 grams (5.3 oz) of R290 refrigerant without having to employ costly leakage detection and ventilation systems. This charge restriction typically limits the refrigeration capacity of systems employing R290 as a refrigerant and further limits endless rows of display cabinets that may meet both energy requirements and charge volume requirements employing R290 as a refrigerant. As such, there exists a need for increasing the refrigeration capacity of said systems without increasing the charge amount of refrigerant as well as providing for endless rows of display cabinets employing R290 as a refrigerant.

[0075] In some embodiments, the refrigeration systems described herein may utilize a capillary tube for the expansion device. In one example, the presently disclosed refrigeration system is configured to minimize 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. Said differently, the refrigeration circuit of the systems described herein may include a suction line and a capillary tube functioning as at least a portion of the liquid line so as to minimize the dimensions (e.g., length or the like) of the liquid line. In doing so, these systems may operate to minimize volume capacity using top-mounted condensers without exceeding the maximal amount of R290 permitted without leakage detection and ventilation as described above.

[0076] With reference to FIGS. 1A and 1B, a refrigeration system 100 is illustrated in accordance with an example embodiment of the present disclosure. The refrigeration system 100 includes at least one refrigerated display cabinet 10 (e.g., display cabinet 10) and a refrigeration circuit 20. The refrigerated display cabinet 10 includes any refrigerated device or appliance (e.g., a refrigerator, cooler, and/or the like) configured to maintain a temperature-regulated interior environment (e.g., a conditioned space). In one example, the refrigerated display cabinet 10 defines a conditioned space enclosed by four (4) walls, a cabinet bottom, and a cabinet top, where at least one of the four walls includes a door 30. The door 30 may provide selective access to the interior of the system 100 (e.g., access to the conditioned space), such as by moving from a closed position (e.g., in which fluid communication between the conditioned space and the ambient environment is precluded) to an open position. In one example, the door 30 may be at least partially transparent, such that the interior environment of the refrigerated display cabinet 10 is visible when the door 30 is closed. In some examples, the interior environment may define one or more shelves 40, racks, ledges, and/or similar structures configured to hold items for display. Although illustrated as a substantially rectangular conditioned space, the present disclosure contemplates that the dimensions (e.g., size and shape) of the refrigerated display cabinet 10 and associated conditioned space may vary based on the intended application of the refrigeration system 100. In one example, the space (e.g., conditioned spaced) regulated within the refrigerated display cabinet 10 may be configured to maintain a temperature at or above the freezing point of water at a fixed altitude or barometric pressure range (e.g., avoiding a temperature at which water freezes). In one example, the space regulated within the refrigerated display cabinet 10 may be configured to maintain food at a temperature at or above the freezing point of water at a fixed altitude or barometric pressure range.

[0077] In one example, the refrigerated display cabinet 10 may be oriented in normal use with a top and a base, where references to horizontal and vertical should be understood with reference to such an orientation. In one example, the refrigerated display cabinet 10 may have a vertical dimension between the top and the base thereof, and a horizontal dimension or depth between the front and back, as well as a width between two sides. The conditioned space may be accessible from a front of the refrigerated display cabinet 10. In one example, the refrigerated display cabinet 10 has a height greater than 1.5 m, greater than 2 m. In one example, the refrigerated display cabinet 10 has a height of about 2.5 m or less. In one example, the refrigerated display cabinet 10 can be irregularly shaped to accommodate the positioning of refrigeration circuit components.

[0078] In one example, the refrigeration system 100 comprises multiple display cabinets 10, where each refrigerated display cabinet 10 comprises a refrigeration circuit 20. Each refrigerated display cabinet 10 may be removably coupled to one or more other display cabinets 10. For example, each of the multiple refrigerated display cabinets 10 may be removably coupled side-by-side (e.g., adjacent) to one another in order to form a row of coupled display cabinets 10. The temperature of the refrigerated display cabinet 10 is maintained by a refrigeration circuit 20 installed on, mounted to, or otherwise associated with the display cabinet 10.

[0079] As illustrated in FIG. 2A, the refrigeration circuit 20 includes a group of interior components 106 positioned or installed within the conditioned space of the refrigerated display cabinet 10 and a compressor-condenser assembly 108 positioned outside of the conditioned space of the refrigerated display cabinet 10. In an example, the interior components 106 and the compressor-condenser assembly 108 (e.g., exterior components) comprise or otherwise form the refrigeration system 100. In an example, the refrigerated display cabinet 10 comprises additional groups of system components in order to increase the overall refrigeration capacity of the display cabinet 10. In an example, the interior components 106 and the compressor-condenser assembly 108 are coupled together via at least one capillary tube 18 and a suction line 13 as described in greater detail with respect to FIG. 3. In an example, the interior components 106 are positioned within an area of the conditioned space that allows for airflow between the interior components 106 and the rest of the conditioned space.

[0080] As illustrated in FIG. 2B, the at least one capillary tube 18 and the suction line 13 are configured to pass through a hole 110, aperture, or opening in a wall or ceiling of the display cabinet 10. The at least one capillary tube 18 and suction line 13 are further configured to removably connect to one or more quick disconnect fittings 112 coupled to the compressor-condenser assembly 108. The quick disconnect fittings 112 (e.g., push fittings, ARO-type couplings, industrial interchange plugs, and/or the like) are configured to allow an installer or operator of the refrigeration system 100 to connect and/or disconnect the at least one capillary tube 18 and suction line 13 from the compressor-condenser assembly 108 without the use of hand tools such as a wrench. Furthermore, the quick disconnect fittings 112 may be configured to removably couple the compressor-condenser assembly 108 with the refrigeration circuit of a refrigerated display cabinet 10, such that the compressor-condenser assembly 108 may be installed on site (e.g., at the installation of the refrigerated display cabinet 10) while maintaining a charge of refrigerant within the system 10.

[0081] With reference to FIG. 3, a block diagram illustrating the refrigeration circuit 20 is illustrated in accordance with one example of the present disclosure. As shown, the refrigeration circuit 20 is configured for use in the display cabinet 10. In an example, the refrigeration circuit 20 comprises a source of power connected in series with a controller. In an example, the source of power comprises any direct current (DC) or alternating current (AC) voltage source (e.g., a generator, battery, fuel cell, and/or the like) configured to provide power to components of the refrigeration system 10. FIG. 3 further depicts a compressor 2 communicably coupled to an input of a condenser 3. The input of the condenser 3 leads to one or more outputs, where each of the one or more outputs is communicably coupled to a capillary tube 18. Each capillary tube 18 comprises an output that is communicably coupled to an input of an evaporator 4. Each of the one or more evaporators 4 comprise an evaporator output which is communicably coupled to the compressor 2 via a suction line 13. In an example, a condenser fan is positioned proximate the condenser 3 and one or more evaporator fans are positioned proximate the first and second evaporators. The controller and the source of power are communicably coupled to the compressor 2.

[0082] In one example, the condenser 3 may be a liquid cooled condenser. In one example, the refrigerated display cabinet 10 is a semi-plug in refrigerated display cabinet, where cooling fluid, such as water or a brine solution, is provided to the condenser 3 from a cooling fluid supply. In one example, the condenser 3 is a shell and tube heat exchanger, or the like, configured to exchange heat between the cooling liquid and the relatively hot refrigerant of the refrigeration circuit. In examples where the condenser is a liquid cooled condenser the condenser 3 may not have a corresponding condenser fan so as to reduce both noise and spatial requirements at the condenser 3.

[0083] In one example, an evaporator fan is provided proximate to the evaporator 4. The evaporator 4 and the evaporator fan may be configured to cool the conditioned space, such that the evaporator 4 and the evaporator fan may be configured to exchange heat between the relatively cold refrigerant at the condenser 3 and the relatively hot atmosphere within the conditioned space. In an example, the refrigeration circuit 20 may further include a temperature probe that is communicably coupled to the controller. In an example, the temperature probe includes a thermometer or other temperature-measuring device positioned within the conditioned space of the refrigerated display cabinet 10. The temperature probe is configured to measure a temperature, or one or more temperature thresholds, of the conditioned space and transmit data to the controller.

[0084] In one example, the source of power comprises any direct current (DC) or alternating current (AC) voltage source capable of providing power to one or more system 100 components. In one example, the controller is any ignition-proof electronic controller configured to provide logic and decisioning for the refrigeration system 100. In one example, the controller is configured to activate the compressor 2 in order to maintain and/or cycle about a set temperature point or between temperature thresholds or set points. In one example, the controller is configured to maintain a set point between approximately 30 degrees Celsius (86 degrees Fahrenheit) and approximately 40 degrees Celsius (104 degrees Fahrenheit) and is configured to activate the compressor 2 when a sensed temperature deviates by approximately one to three degrees from the set point. In some examples, the presently disclosed system 100 may comprise multiple compressors 2 and may therefore include a controller configured to activate each compressor sequentially, for example, for avoiding an excessive surge in amperage which would result from each compressor 2 activating simultaneously. For example, the controller may be configured to activate each compressor 2 sequentially based on a sensed temperature from the temperature probe, a change in temperature, a manual input, or an event exceeding or falling below a temperature threshold. In one example, electrical components of the refrigeration system 100 (such as the controller) are either solid state or sealed so as to not be a potential source of ignition in the event of a leak.

[0085] In an example, the refrigeration circuit 20 is configured to receive a refrigerant (not shown). The liquid refrigerant is configured to pass into the inputs of the first and second evaporators. The at least one evaporator fan may be positioned near the evaporators 4 and is configured to direct atmospheric air over the evaporators 4, causing evaporation of the liquid refrigerant. As described herein, the embodiments of the presently disclosed system 100 leverage quick disconnect fittings that removably couple the compressor-condenser assembly 108 with the refrigeration circuit of a refrigerated display cabinet 10, such that the compressor-condenser assembly 108 may be installed on site (e.g., at the installation of the refrigerated display cabinet 10) while maintaining a charge of refrigerant within the system 10. Said differently, the charge of the liquid refrigerant within the system 100 (e.g., within the refrigeration circuit 20) may be maintained (e.g., leakage prevented) via the use of the quick disconnect fittings used to communicably coupled the refrigeration circuitry 20 and the compressor-condenser assembly 108.

[0086] In one example, the compressor 2 is configured to pull cold, low-pressure gaseous refrigerant from the evaporator 4 into a compressor input. In some examples, the compressor 2 pulls the cold refrigerant through the suction line 13, thermally coupled to the one or more capillary tubes 18. The compressor 2 then raises the temperature and pressure of the refrigerant and outputs the heated refrigerant into an input of the condenser 3. In one example, the at least one condenser fan is positioned near the condenser 3 and is configured to direct atmospheric air over the condenser 3, causing the refrigerant to cool from a gaseous state to a liquid state. The refrigerant then flows through the at least one capillary tube 18 from an output of the condenser 3 into an input of the evaporator 4 for evaporative cooling. Before reaching the input of the evaporator 4, the cooled refrigerant in the at least one capillary tube 18 is thermally coupled to heat exchanger 16. In an example, heat exchanger 16 couples the at least one capillary tube 18 and suction line 13 in a thermally coupled relationship.

[0087] In an example, heat exchanger 16 comprises the at least one capillary tube 18 and suction line 13 in a thermally coupled relationship with a conductive material such as copper, aluminum, stainless steel, and/or combinations thereof. In an example, heat exchanger 16 comprises a length of the at least one capillary tube 18 and a length of the suction line 13 soldered together which functions as heat exchanger 16. The length and/or composition of solder for thermally coupling the at least one capillary tube 18 and the suction line 13 can be determined based on an efficiency threshold or other system parameters. The length and diameter of the at least one capillary tube 18 are chosen with respect to at least one of compressor 2 specifications, among other specifications, using techniques known in the art.

[0088] In some examples, the refrigeration circuit 20 may be configured for use in a display cabinet 10. In one example, a single refrigeration circuit 20 is sufficient to provide the total refrigeration capacity of the display cabinet 10, or alternatively, multiple refrigeration circuits 20 are installed in order to provide sufficient refrigeration capacity. In one example, refrigeration circuit 20 is configured within the refrigerated display cabinet 10 such that the condenser 3 and at least one condenser fan are positioned outside of the conditioned space of the display cabinet 10. In another example, the at least one evaporator 4 and at least one evaporator fan are positioned within the conditioned space. In one example, the condenser 3 and condenser fan are separated from the evaporators via a ceiling or barrier. By, in some embodiments, removably attaching the compressor-condenser assembly 108 with the refrigerated display cabinet 10 (e.g. on the top surface or the like), the compressor-condenser assembly 108 may be installed on site (e.g., at the installation location of the system 100). Furthermore, the use of quick disconnect fittings to removably attached the compressor-condenser assembly 108 with the refrigeration circuit 20 may, in such an embodiment, allow the compressor-condenser assembly 108 to be initially charged with the maximum amount of refrigerated (e.g., as defined by applicable regulation) prior to installation. Said differently, the compressor-condenser assembly 108 with quick disconnect fittings described herein may allow the maximum amount of refrigerant that is used by the system 100 to be provided by the installation of the compressor-condenser assembly 108 with the refrigeration circuit 20 as opposed to the system 100 being charged with refrigerant after installation.

[0089] With reference to FIG. 4A a bottom surface 11 of the refrigerated display cabinet 10 is illustrated in accordance with an example embodiment of the present disclosure. In an example, the at least one evaporator 4 is positioned on the bottom surface 11 within the conditioned space of the display cabinet 10. The suction line 13 and at least one capillary tube 18 are configured to pass through an aperture of a wall of the refrigerated display cabinet 10 to communicably couple with inputs of the one or more evaporators 4. With reference to FIG. 4B, an aerial perspective of the bottom surface 11 is illustrated in which the one or more evaporator fans 7 are positioned adjacent to the one or more evaporators 4 on the bottom surface 11.

[0090] In some examples, the refrigeration circuit 20 is configured to receive a refrigerant having a GWP (Global Warming Potential) value less than 10. Specifically, the refrigeration circuit 20 is configured to receive R290 refrigerant (i.e., propane), which has a GWP value of 3. The current charge limit for R290 is 150 gm (5.3 oz) per compressor (without leakage detection and ventilation) in the United States, and therefore the refrigeration circuit 20 is configured to receive a charge less than 5.3 oz of R290 refrigerant per compressor without leakage detection and ventilation.

[0091] With reference to FIGS. 5A-5B, example disconnect fittings 112 of the present disclosure are illustrated. As shown, the compressor-condenser assembly 108 may include a first disconnect fitting 116 coupling the input of the compressor 2 to the refrigeration circuit 20, and a second disconnect fitting 114 coupling the output of the condenser 3 to the refrigeration circuit 20. In some examples, the input of the compressor 2 is communicably coupled to the suction line 13 via the first disconnect fitting 116. In some embodiments, the output of the condenser 3 is communicably coupled to the capillary tube 18 via the second disconnect fitting 114. As described above, the first and the second quick disconnect fittings 116, 114 may include, without limitation, any snap type (ball latching), non-latching, single shut-off, double shut-off, or dry break couplings operable by one or two hands. In one example, the quick disconnect fittings 112 of the present disclosure include shut-off valves within both the internal and external ends so as to retain pressure in the components in fluid communication via the quick disconnect fittings. As would be evident to one of ordinary skill in the art in light of the present disclosure, the fitting type defined by the compressor-condenser assembly 108 may be complimentary to the fitting type defined by the capillary tube 18/suction line 13 (e.g., a male to female connection scheme).

[0092] As described herein, the quick disconnect fittings 112 of the present disclosure may be used as an attachment mechanism for an example compressor-condenser assembly 108 such that the pressure within the fluid lines in fluid communication with (e.g., communicably coupled with) the compressor-condenser assembly is maintained and the charge of the refrigerant within the same is maintained. As shown, the refrigeration system 100 may utilize a capillary tube 18 for the expansion device so as to minimize the dimensions (e.g., length or the like) of the liquid line 118. In doing so, these systems may operate to minimize volume capacity using top-mounted condensers without exceeding the maximal amount of R290 permitted without leakage detection and ventilation as described above.

[0093] It should be understood that while an exemplary system configuration is depicted with respect to the figures, these examples are non-limiting. It is envisioned that additional or alternative configurations may be included in the design of the refrigerant circuit, specifically depending on the specifications of the display cabinet. While certain exemplary examples have been described and shown in the accompanying drawings, it is to be understood that such examples are merely illustrative of and not restrictive on the broad disclosure, and that this disclosure not be limited to the specific constructions and arrangements shown and described, since various other changes, combinations, omissions, modifications and substitutions, in addition to those set forth in the above paragraphs, are possible. Those skilled in the art will appreciate that various adaptations, modifications, and combinations of the just described examples can be configured without departing from the scope and spirit of the present disclosure. Therefore, it is to be understood that, within the scope of the appended claims, the present disclosure may be practiced other than as specifically described herein.

[0094] Also, it will be understood that, where possible, any of the advantages, features, functions, devices, and/or operational aspects of any of the examples of the present disclosure described and/or contemplated herein are combinable and/or included in any of the other examples of the present disclosure described and/or contemplated herein, and/or vice versa. In addition, where possible, any terms expressed in the singular form herein are meant to also include the plural form and/or vice versa, unless explicitly stated otherwise.