AIR CONDITIONER SYSTEM LEAK MITIGATION

Description

FIELD OF THE INVENTION

The present subject matter relates generally to air conditioner systems, and more particularly to air conditioner systems configured for mitigating refrigerant leaks therefrom and related methods for mitigating refrigerant leaks.

BACKGROUND OF THE INVENTION

Air conditioner systems or air conditioning systems are conventionally utilized to adjust the temperature within structures such as dwellings and office buildings. A typical air conditioner or air conditioning system includes an indoor portion comprising one or more indoor units and an outdoor portion comprising at least one outdoor unit. Each of the indoor unit(s) and the outdoor unit(s) generally includes a heat exchanger by which thermal energy is transferred between refrigerant in a sealed cooling system and air. The indoor portion generally communicates (e.g., exchanges air) with the area within a building, and the outdoor portion generally communicates (e.g., exchanges air) with the area outside a building. Generally, the indoor unit may include a fan operable to rotate to motivate air through the indoor unit, or each indoor unit (when the indoor portion includes multiple indoor units) may include such a fan. Another fan (or fans) may be operable to rotate to motivate air through the outdoor portion. The sealed cooling system includes a compressor, and the sealed cooling system is generally coupled to the indoor unit(s) and the outdoor unit(s) to treat (e.g., cool or heat) air as it is circulated through the units. One or more control boards are typically provided to direct the operation of various elements of the particular air conditioner system.

In some instances, refrigerant may escape from the sealed cooling system. Such refrigerant leaks may, if left undetected or untreated, result in undesirable accumulations of gaseous refrigerant in indoor spaces, e.g., enclosed spaces.

As a result, further improvements to air conditioner systems may be advantageous. In particular, it would be useful to provide systems and methods for responding to a refrigerant leak, such as mitigating or avoiding accumulation of refrigerant in enclosed spaces.

BRIEF DESCRIPTION OF THE INVENTION

Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

In one exemplary aspect of the present disclosure, a method of operating an air conditioner system is provided. The air conditioner system includes an outdoor unit, an indoor unit, and a sealed cooling system coupled between the outdoor unit and the indoor unit to circulate refrigerant through an indoor heat exchanger of the indoor unit and an outdoor heat exchanger of the outdoor unit. The method includes detecting a refrigerant leak at the indoor unit and shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak.

In another exemplary aspect of the present disclosure, an air conditioner system is provided. The air conditioner system includes an outdoor unit, an indoor unit, and a sealed cooling system coupled between the outdoor unit and the indoor unit. The sealed cooling system is operable to circulate refrigerant through an indoor heat exchanger of the indoor unit and an outdoor heat exchanger of the outdoor unit. The air conditioner system also includes a controller. The controller is configured for detecting a refrigerant leak at the indoor unit and shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak.

These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures.

FIG. 1 provides a schematic illustration of an air conditioner system according to one or more exemplary embodiments of the present disclosure.

FIG. 2 provides a flowchart illustrating an exemplary method of operating an air conditioner system according to one or more additional exemplary embodiments of the present disclosure.

DETAILED DESCRIPTION

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

As used herein, the terms “includes” and “including” are intended to be inclusive in a manner similar to the term “comprising.” Similarly, the term “or” is generally intended to be inclusive (i.e., “A or B” is intended to mean “A or B or both”). The terms “upstream” and “downstream” refer to the relative flow direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the flow direction from which the fluid flows, and “downstream” refers to the flow direction to which the fluid flows.

As used herein, terms of approximation, such as “generally,” or “about” include values within ten percent greater or less than the stated value. When used in the context of an angle or direction, such terms include within ten degrees greater or less than the stated angle or direction. For example, “generally vertical” includes directions within ten degrees of vertical in any direction, e.g., clockwise or counterclockwise.

Turning now to the figures, FIG. 1 illustrates an exemplary air conditioner system 100. The exemplary air conditioner system 100 may be generally known as a split system or a multi-split system, e.g., the air conditioner system 100 may include an outdoor portion 102, e.g., positioned outside of the structure to be cooled, and an indoor portion 104, e.g., positioned inside of the structure to be cooled. The outdoor portion 102 may include an outdoor unit 106, and the outdoor unit 106 may include an outdoor heat exchanger 108 and an outdoor fan 110. The indoor portion 104 may include at least one indoor unit 112, and the indoor unit 112 may include an indoor heat exchanger 114 and an indoor fan 116. In embodiments where multiple indoor units are provided, each indoor unit may be a substantial duplicate of every other indoor unit, e.g., each indoor unit may include a heat exchanger and a fan similar to those illustrated in FIG. 1. Accordingly, only a single indoor unit 112 is illustrated in FIG. 1 for the sake of clarity. The indoor unit 112 may be located in an enclosed space 180, such as a room, a mechanical closet, or other portion of the structure to be cooled. A refrigerant sensor 182 may be provided in the enclosed space 180, such as on the indoor unit 112, or remote from the indoor unit 112 as illustrated in FIG. 1.

Air conditioner system 100 also includes a sealed cooling system 130, e.g., generally comprising a series of conduits interlinking a compressor 118, the outdoor heat exchanger 108, the indoor heat exchanger 114 (as well as additional indoor heat exchangers of any other indoor units which may be provided), and other refrigerant flow components. Compressor 118 is operable to compress the refrigerant. Accordingly, the pressure and temperature of the refrigerant may be increased in compressor 118 such that the refrigerant becomes a more superheated vapor. The sealed cooling system may be a thermodynamic assembly, which may be operated as a refrigeration assembly (and thus perform a refrigeration cycle) or operated as a heat pump (and thus perform a heat pump cycle). Thus, as is understood, the exemplary air conditioner system 100 may be selectively operated to perform a refrigeration cycle at certain instances (e.g., while in a cooling mode) and a heat pump cycle at other instances (e.g., while in a heating mode). The compressor 118 may be in fluid communication with the heat exchangers 108, 114 to flow refrigerant therethrough, as is generally understood. The outdoor and indoor heat exchangers 108, 114 may each include coils, through which the refrigerant may flow for heat exchange purposes, as is generally understood. Moreover, as may be seen in FIG. 1, heat exchangers 108, 114 may each include multiple circuits therethrough.

Operation of the air conditioner system 100 in heating mode or cooling mode may be controlled or selected based on the position of a reversing valve 120, which may be, for example, a four-way valve. The reversing valve 120 selectively directs compressed refrigerant from compressor 118 to either indoor heat exchanger 114 or outdoor heat exchanger 108. The direction of refrigerant flow through the sealed system 130 in cooling mode is indicated by solid line arrows in FIG. 1, and the direction of refrigerant flow through the sealed cooling system 130 in heating mode is indicated by dashed line arrows in FIG. 1. For example, in cooling mode, reversing valve 120 is arranged or configured to direct compressed, e.g., high-pressure, vapor refrigerant from compressor 118 to outdoor heat exchanger 108. Conversely, in heating mode, reversing valve 120 is arranged or configured to direct compressed, e.g., high-pressure, vapor refrigerant from compressor 118 to indoor heat exchanger 114. Thus, reversing valve 120 permits sealed system 130 to adjust between the heating mode and the cooling mode, as will be understood by those skilled in the art.

In cooling mode, the outdoor heat exchanger 108 acts as a condenser, e.g., outdoor heat exchanger 108 is operable to reject heat into the exterior atmosphere, when sealed system 130 is operating in the cooling mode. For example, the superheated vapor from compressor 118 may enter outdoor heat exchanger 108 from reversing valve 120. Within outdoor heat exchanger 108, the refrigerant transfers energy to the exterior atmosphere and condenses into a saturated liquid and/or liquid-vapor mixture. The exterior air handler or fan 110 positioned adjacent outdoor heat exchanger 108 may facilitate or urge a flow of air from the exterior atmosphere across outdoor heat exchanger 108 in order to facilitate heat transfer.

In cooling mode, indoor heat exchanger 1114 acts as an evaporator. Thus, indoor heat exchanger 114 is operable to heat refrigerant within indoor heat exchanger 114 with energy from the indoor atmosphere when sealed system 130 is operating in the cooling mode. For example, the liquid or liquid-vapor mixture refrigerant may enter indoor heat exchanger 114. Within indoor heat exchanger 114, the refrigerant receives energy from the indoor atmosphere and vaporizes into superheated vapor and/or high quality vapor mixture. An indoor air handler or fan 116 positioned adjacent indoor heat exchanger 114 may facilitate or urge a flow of air from the indoor atmosphere across indoor heat exchanger 114 in order to facilitate heat transfer.

During operation of sealed system 130 in the heating mode, reversing valve 120 reverses the direction of refrigerant flow through sealed system 130. Thus, in the heating mode, indoor heat exchanger 114 is disposed downstream of compressor 118 and acts as a condenser, e.g., such that indoor heat exchanger 114 is operable to reject heat into the indoor atmosphere. In addition, outdoor heat exchanger 108 acts as an evaporator in the heating mode, e.g., such that outdoor heat exchanger 108 is operable to heat refrigerant within outdoor heat exchanger 108 with energy from the exterior atmosphere.

The air conditioner system 100 may further include a gas service valve 122 and a liquid service valve 124. The air conditioner system 100 may also include temperature sensors 166 at various locations throughout the system 100. The air conditioner system 100 may further include an outdoor expansion valve 126 and a strainer 128. A high-pressure switch 140 may be provided on one side of the compressor 118 and a low-pressure switch 142 may be provided on the other side of the compressor 118. Furthermore, a capillary tube 144 and an oil separator 146 may be coupled to the compressor 118. The air conditioner system 100 may further include an accumulator 150 configured to retain liquid-phase refrigerant therein and thus prevent liquid refrigerant flooding the compressor 118 (e.g., the liquid-phase refrigerant may accumulate within the accumulator 150 such that the liquid-phase refrigerant does not reach the compressor 118). A check valve 152 may be coupled to the accumulator 150 and may be positioned and configured to permit refrigerant flow to the accumulator 150 and prevent or limit refrigerant flow away from the accumulator 150.

An expansion device, e.g., electronic expansion valve 160, may be positioned indoors, e.g., in the indoor portion 104 of the air conditioner system 100, downstream of the liquid service valve 124 and upstream of the indoor heat exchanger 114 when the air conditioner system 100 is in cooling mode. When multiple indoor units 112 are provided, an expansion valve 160 may be provided for each indoor unit 114. The electronic expansion valve or valves 160 may generally expand the refrigerant, lowering the pressure and temperature thereof. The refrigerant may then be flowed through indoor heat exchanger 114. Additionally, the electronic expansion valve(s) 160 may be actuated, such as by a stepper motor, to selectively increase or reduce the flow rate of refrigerant therethrough. A strainer 162 may be provided between the electronic expansion valve 160 and the indoor heat exchanger 114.

As mentioned, the air conditioner system 100 may be a multi-split system having one or more indoor units 112 in addition to the one illustrated example indoor unit 112. Refrigerant branches 164 extending to and from such additional indoor units are partially illustrated in FIG. 1 by way of example.

The operation of air conditioner 100 including compressor 118 (and thus the sealed system 130 generally), indoor fan 116, outdoor fan 110, and other suitable components may be controlled by a control board or controller 158. Controller 158 may be in communication (via for example a suitable wired or wireless connection) with such components of the air conditioner 100. Controller 158 may also be in communication with various sensors, e.g., sensors 166 and 182, in the air conditioner system 100. By way of example, the controller 158 may include a memory and one or more processing devices such as microprocessors, CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of air conditioner system 100. The memory may be a separate component from the processor or may be included onboard within the processor. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor. Alternatively, controller 158 may be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software. Further, it should be understood that controllers 158 as disclosed herein are capable of and may be operable to perform any methods and associated method steps as disclosed herein.

It should be understood that the illustrated air conditioner system 100 is generally referred to as a split system, and this configuration is provided by way of example only. The benefits of the present disclosure apply to other types and styles of air conditioner systems as well. Consequently, the description set forth herein is for illustrative purposes only and is not intended to be limiting in any aspect to a particular air conditioner unit configuration.

Turning now to FIG. 2, embodiments of the present disclosure may also include methods of operating an air conditioner system, such as the example method 400 illustrated in FIG. 2. Such methods may be used with any suitable air conditioner system, such as air conditioner system 100 as described above.

For example, as mentioned above, the air conditioner system 100 may include a controller 158 and the controller 158 may be operable for, e.g., configured for, performing some or all of the methods and/or steps thereof described herein. For example, one or more method steps may be embodied as an algorithm or program stored in a memory of the controller 158 and executed by the controller 158 in response to a user input.

As illustrated in FIG. 2, method 400 may include (410) detecting a refrigerant leak at the indoor unit and (420) shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak.

In some embodiments, method 400 may further include, e.g., (420) shutting off refrigerant flow may include, (422) shutting off a compressor of the air conditioner system. In some embodiments, (420) shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak may include (424) switching a reversing valve of the air conditioner system to cooling mode. In additional embodiments, (420) shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak may include (426) fully closing an electronic expansion valve in an indoor portion of the sealed cooling system upstream of the indoor unit. For example, the electronic expansion valve which is fully closed at (426) may be downstream of a liquid service valve, such as the electronic expansion valve may be electronic expansion valve 160 illustrated in FIG. 1 and described above. In further embodiments, (420) shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak may include (428) fully closing an electronic expansion valve in the sealed cooling system between a liquid service valve and the outdoor heat exchanger, such as the electronic expansion valve which is fully closed at (428) may be electronic expansion valve 126 illustrated in FIG. 1 and described above.

In some embodiments, (420) shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak may include more than one of (422), (424), (426), and (428). For example, in embodiments where (420) includes more than one of the foregoing exemplary processes, such multiple processes may be performed simultaneously in response to the detected refrigerant leak at the indoor unit. For example, method 400 may include, e.g., (420) shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak may include shutting off a compressor of the air conditioner system, switching a reversing valve of the air conditioner system to cooling mode, and fully closing at least one electronic expansion valve in the sealed cooling system. For example, such embodiments may include fully closing an electronic expansion valve in an indoor portion of the sealed cooling system upstream of the indoor unit and/or fully closing an electronic expansion valve in the sealed cooling system between a liquid service valve and the outdoor heat exchanger. In such embodiments, shutting off the compressor, switching the reversing valve to cooling mode, and fully closing the at least one electronic expansion valve (e.g., fully closing the electronic expansion valve in the indoor portion of the sealed cooling system upstream of the indoor unit and/or fully closing the electronic expansion valve in the sealed cooling system between the liquid service valve and the outdoor heat exchanger) may be all performed simultaneously.

As mentioned above, the air conditioner system may include more than one indoor unit, such as about five indoor units. In some embodiments which include more than one indoor unit, method 400 may include shutting off all indoor units, or isolating and only shutting down the indoor unit at which the leak was detected. For example, the indoor unit at which the leak is detected may be a first indoor unit of a plurality of indoor units, and shutting off refrigerant flow to the first indoor unit in response to the detected refrigerant leak may include shutting off refrigerant flow to each indoor unit of the plurality of indoor units. As another example when the indoor unit at which the refrigerant leak was detected is a first indoor unit of a plurality of indoor units, shutting off refrigerant flow to the first indoor unit in response to the detected refrigerant leak may include shutting off refrigerant flow to only the first indoor unit while continuing to provide refrigerant flow to every other indoor unit of the plurality of indoor units. For example, shutting off refrigerant flow to only the first indoor unit may include fully closing only the one electronic expansion valve (e.g., electronic expansion valve 160) that is coupled to the first indoor unit.

Each indoor unit may have a refrigerant sensor (e.g., refrigerant sensor 182) associated therewith, such as mounted on the indoor unit or otherwise within the same enclosed space 180 (e.g., room, etc., as described above) as the indoor unit. The indoor unit at which the leak is detected may be identified based on the association thereof with the particular refrigerant sensor which detected the leak.

In some embodiments, (420) shutting off refrigerant flow to the indoor unit in response to the detected refrigerant leak may include preventing, by a check valve coupled to an accumulator of the air conditioner system, refrigerant from flowing away from the accumulator. For example, a check valve such the exemplary check valve 152 illustrated in FIG. 1 and described above may be provided and may prevent the liquid refrigerant stored in the accumulator (e.g., accumulator 150) from draining back to the indoor unit, such as when the compressor is shut off and the pressure of the refrigerant within the sealed system is thereby reduced.

The air conditioner system may also include a user interface, such as a display and one or more user input devices. In some embodiments, the user interface, e.g., the display thereof, may be configured for, and exemplary methods may include, providing a user notification in response to the detected refrigerant leak. The user notification may be or may include a visual notification, e.g., on the display, an audible notification, e.g., a beep, chime, or other alert sound, or combinations of audible and visual notifications. The user notification may be provided locally, e.g., on a user interface of the air conditioner system 100 that is onboard the air conditioner system, e.g., directly physically integrated into the air conditioner system, and/or may be provided remotely, e.g., on a remote user interface such as a computer (e.g., personal computer or tablet computer), smartphone, or other similar device which is spaced apart from the air conditioner system 100 and in wireless communication with the air conditioner system 100, e.g., with the controller 158 thereof.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.