Patent Application
20250237405
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
The present disclosure relates generally to refrigerant leak detection assemblies in a heating, ventilating, and/or air conditioning (HVAC) system, such as a rooftop unit (RTU).
An HVAC system provides ventilation and maintains air quality in a confined space, such as a commercial or a household building. The HVAC system circulates a refrigerant through a closed circuit (e.g., refrigerant loop or circuit, vapor compression loop or circuit) including a compressor, a condenser, an expansion device, and an evaporator. Refrigerant in the evaporator is utilized to cool an air flow via thermal exchange to condition the confined space. However, traditional refrigerants possess certain drawbacks. Although such traditional refrigerants are effective coolants, for example, they may have high global warming potential (GWP). High GWP refrigerants have been replaced in certain traditional configurations with more environmentally friendly refrigerants, such as A2L refrigerants. Although A2L refrigerants have relatively low GWP, they may be flammable. Accordingly, it is now recognized that improved HVAC systems and methods mitigating technical problems associated with A2L refrigerants are desired.
A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below.
In one embodiment, a rooftop unit for a heating, ventilation, and air conditioning (HVAC) system includes a housing and a retention bracket mounted within the housing. The retention bracket includes a retention surface, a first retention flange extending from the retention surface, and a second retention flange extending from the retention surface, where the retention surface, the first retention flange, and the second retention flange define a retention channel. The rooftop unit also includes a refrigerant sensor assembly having a refrigerant detection sensor configured to detect a refrigerant and a mounting bracket configured to support the refrigerant detection sensor. The mounting bracket includes a mounting surface, a plurality of side flanges extending from the mounting surface, and a mounting flange extending from the mounting surface. The refrigerant detection sensor is configured to be attached to the mounting surface, and the mounting flange is configured to be secured to the retention surface in an installed configuration of the refrigerant sensor assembly within the housing.
In another embodiment, a packaged unit of a heating, ventilation, and air conditioning (HVAC) system includes a housing defining a blower section, a blower disposed within the blower section of the housing, a refrigerant circuit conduit extending through the blower section of the housing, and a retention bracket mounted within the blower section of the housing, where the retention bracket defines a retention channel. The packaged unit further includes a refrigerant sensor assembly having a refrigerant detection sensor configured to detect a refrigerant and a mounting bracket configured to support the refrigerant detection sensor. The mounting bracket includes a mounting surface, a plurality of side flanges extending from the mounting surface, and a mounting flange extending from the mounting surface. The refrigerant detection sensor is configured to be attached to the mounting surface, and the mounting flange is configured to be secured to the retention bracket in a predetermined orientation of the refrigerant sensor assembly relative to the retention bracket.
In a further embodiment, a rooftop unit of a heating, ventilation, and air conditioning (HVAC) system includes a housing, refrigerant circuit extending through the housing, where the refrigerant circuit includes a suction conduit configured to direct a refrigerant from a heat exchanger of the rooftop unit to a compressor of the rooftop unit, and a retention bracket mounted within the housing, where the retention bracket extends along the suction conduit, the retention bracket includes a retention surface, and the retention bracket defines a retention channel. The rooftop unit further includes refrigerant sensor assembly having a refrigerant detection sensor configured to detect a refrigerant and a mounting bracket configured to support the refrigerant detection sensor. The mounting bracket includes a mounting surface, a plurality of side flanges extending from the mounting surface, and a mounting flange extending from the mounting surface. The refrigerant detection sensor is configured to be attached to the mounting surface, and the mounting flange is configured to be disposed within the retention channel and secured to the retention surface in an installed configuration of the refrigerant sensor assembly within the housing. In the installed configuration of the refrigerant sensor assembly, the refrigerant detection sensor is disposed atop the mounting surface, relative to a direction of gravity, and the refrigerant sensor assembly is disposed above the suction conduit, relative to the direction of gravity.
Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which:
One or more specific embodiments will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be noted that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.
As used herein, the terms “approximately,” “generally,” “substantially,” and so forth, are intended to convey that the property value being described may be within a relatively small range of the property value, as those of ordinary skill would understand. For example, when a property value is described as being “approximately” equal to (or, for example, “substantially similar” to) a given value, this is intended to convey that the property value may be within +/−5%, within +/−4%, within +/−3%, within +/−2%, within +/−1%, or even closer, of the given value. Similarly, when a given feature is described as being “substantially parallel” to another feature, “generally perpendicular” to another feature, and so forth, this is intended to convey that the given feature is within +/−5%, within +/−4%, within +/−3%, within +/−2%, within +/−1%, or even closer, to having the described nature, such as being parallel to another feature, being perpendicular to another feature, and so forth. Mathematical terms, such as “parallel” and “perpendicular,” should not be rigidly interpreted in a strict mathematical sense, but should instead be interpreted as one of ordinary skill in the art would interpret such terms. For example, one of ordinary skill in the art would understand that two lines that are substantially parallel to each other are parallel to a substantial degree, but may have minor deviation from exactly parallel.
The present disclosure relates to a refrigerant leak detection assembly (e.g., arrangement) of a heating, ventilation, and/or air conditioning (HVAC) system, such as a rooftop unit (RTU). More particularly, the present disclosure relates to a refrigerant leak detection sensor assembly (e.g., sensor, such as a refrigerant concentration sensor, thermal sensor, and/or other types of refrigerant leak detection sensor) within the HVAC system (e.g., RTU). For example, HVAC systems in accordance with the present disclosure may include low Global Warming Potential (GWP) refrigerants, such as A2L refrigerants, as a heat transfer medium (e.g., working fluid). Because low GWP refrigerants (e.g., A2L refrigerants) may be flammable, among other reasons, HVAC systems employing low GWP refrigerants (e.g., A2L refrigerants) may benefit from refrigerant leak detection sensor assemblies (e.g., refrigerant leak detector assemblies) configured to detect refrigerant leaked from a refrigerant loop or circuit (e.g., vapor compression loop or circuit) of the HVAC system (e.g., RTU). As described in detail below, presently disclosed assemblies of refrigerant leak detection sensors enable reliable and repeatable installation of refrigerant leak detection sensors in a desired location and orientation within the HVAC system. The embodiments described herein reduce, mitigate, and/or block improper installation of refrigerant leak detection sensors (e.g., in unintended locations, in unintended orientations) that may otherwise adversely affect intended operation of the refrigerant leak detection sensors to detect refrigerant leaks promptly, reliably, and effectively. In this way, the refrigerant leak detection sensors may be implemented with HVAC systems to detect refrigerant leaks relatively accurately, relatively reliably, and relatively quickly (e.g., within 5 minutes of onset of the refrigerant leak). These and other aspects of the present disclosure are described in detail below with reference to the drawings.
Turning now to the drawings,
To help illustrate, a building 10 serviced by a heating, ventilating, and air conditioning (HVAC) system 11 is shown in
To facilitate controlling operation of the HVAC equipment, the HVAC system 11 may include a control system. In some embodiments, the control system may be implemented using one or more control devices 16, such as a thermostat, a zone sensor, a zone control board, a pressure transducer, and/or a temperature transducer. For example, a control device 16 may be a thermostat used to designate target air conditions, such as target temperature and/or target humidity level, within the building 10 and/or that measures air conditions present within the building 10.
To facilitate achieving the target air conditions, the control system may control operation of the HVAC unit 12 and/or other HVAC equipment, such as fans or air dampers disposed in the ductwork 14, based at least in part on the target air conditions and measured air conditions. For example, when the difference between the measured temperature and the target temperature is greater than a threshold, the control system may turn on or run the HVAC unit 12 to circulate refrigerant through one or more heat exchangers to facilitate producing temperature-controlled air. Additionally, the control system may turn on a fan and/or adjust position of an air damper to facilitate supplying the temperature-controlled air to internal spaces within the building 10 via the ductwork 14.
To facilitate producing temperature-controlled air, in some embodiments, the HVAC unit 12 may be selectively operated in different modes, such as a first-stage cooling mode, a second-stage cooling mode, a fan only mode, a first-stage heating mode, and a second-stage heating mode. For example, when operating in a heating mode or heat pump mode, the HVAC unit 12 may inject heat to produce heated air, which may then be supplied to internal spaces within the building 10. Additionally, or alternatively, the HVAC system 11 may include a furnace that operates to produce the heated air. Furthermore, when operating in a cooling mode or air conditioning mode, the HVAC unit 12 may extract heat to produce cooled air, which may then be supplied to internal spaces within the building 10.
In some embodiments, the HVAC system 11 may be a split HVAC system, for example, which includes an outdoor HVAC unit and an indoor HVAC unit.
Additionally, or alternatively, an HVAC unit 12 may be a single package unit that includes other equipment, such as a blower, a fan, an integrated air handler, and/or an auxiliary heating unit. For example, in the depicted embodiment, the HVAC unit 12 is a rooftop unit (RTU) that conditions a supply air stream, such as environmental air and/or a return air flow from the building 10.
To help illustrate, an example of a single package HVAC unit 12A is shown in
Furthermore, as in the depicted embodiment, rails 26 may be joined to the bottom perimeter of the housing 24 to provide a foundation for the HVAC unit 12A. For example, the rails 26 may provide access for a forklift and/or overhead rigging to install and/or remove the HVAC unit 12. Additionally, in some embodiments, the rails 26 may fit into “curbs,” for example, implemented on the roof of the building 10 to enable the HVAC unit 12 to provide air to the ductwork 14 while blocking contaminants, such as rain, from leaking into the building 10.
As will be described in more detail below, the environment heat exchanger 28 and the supply air heat exchanger 30 may be included in a refrigerant circuit (e.g., loop) that operates to circulate refrigerant. In particular, the environment heat exchanger 28 and the supply air heat exchanger 30 may each include tubing through which the refrigerant is circulated to facilitate heat exchange between the refrigerant and air. In some embodiments, the tubing may include multichannel tubing, copper tubing, aluminum tubing, and/or the like.
In other words, the environment heat exchanger 28 and the supply air heat exchanger 30 may implement a thermal cycle in which the refrigerant undergoes phase changes and/or temperature changes as it flows through the environment heat exchanger 28 and the supply air heat exchanger 30 to produce heated air and/or cooled air. For example, when operating in a cooling mode, the environment heat exchanger 28 may function as a condenser to extract heat from the refrigerant and the supply air heat exchanger 30 may function as an evaporator to use the refrigerant to extract heat from the air to be supplied to internal spaces within the building 10. On the other hand, when operating in a heating mode, the environment heat exchanger 28 may function as an evaporator to inject heat into the refrigerant and the supply air heat exchanger 30 may function as a condenser to inject heat from the refrigerant into the air to be supplied to internal spaces within the building 10.
To facilitate heat exchange, during operation, the fans 32 may draw environmental or outside air through the environment heat exchanger 28. In this manner, the environmental air may be used to heat and/or cool as the refrigerant as it flows through the tubing of the environment heat exchanger 28. Additionally, a blower assembly 34, powered by a motor 36, may draw air to be supplied to internal portions of the building 10 through the supply air heat exchanger 30. In some embodiments, the supply air may include environmental air, outside air, return air, inside air, or any combination thereof. In any case, in this manner, the refrigerant may be used to heat and/or cool the supply air as it flows through the tubing of the supply air heat exchanger 30.
In some embodiments, the HVAC unit 12 may flow supply air through one or more air filters 38 that remove particulates and/or other air contaminants from the supply air. For example, one or more air filters 38 may be disposed on an air intake side of the supply air heat exchanger 30 to reduce likelihood of contaminants contacting tubing of the supply air heat exchanger 30. Additionally, or alternatively, one or more air filters 38 may be disposed on an air output side of the HVAC unit 12A to reduce likelihood of contaminants being supplied to internal spaces within the building 10.
The HVAC unit 12 also may include other HVAC equipment, such as a compressor 40, a solid-core filter drier, a drain pan, a disconnect switch, an economizer, pressure switches, and/or the like. In some embodiments, the compressor 40 may be a scroll compressor, a rotary compressor, a screw compressor, or a reciprocating compressor. Additionally, in some embodiments, the compressor 40 may be implemented using multiple selectable compressor stages 44. For example, in the depicted embodiment, the compressor 40 is implemented in a dual stage configuration with two compressor stages 44.
In this manner, an HVAC system 11 may be implemented with one or more single package HVAC units 12A. As described above, in other embodiments, an HVAC system 11 may be a split HVAC system. In such embodiments, instead of a single package HVAC unit 12A, the HVAC system 11 may be implemented with split HVAC units, such as an outdoor HVAC unit and an indoor HVAC unit.
To help illustrate, an example of a portion 50 of an HVAC system 11, which includes an indoor HVAC unit 12B and an outdoor HVAC unit 12C, is shown in
Additionally, as depicted, the outdoor HVAC unit 12C includes an environment heat exchanger 28 and a fan 32. As discussed above, in some embodiments, the environment heat exchanger 28 may function as a condenser when in a cooling mode and as an evaporator when in a heating mode.
Furthermore, as depicted, the indoor HVAC unit 12B includes a supply air heat exchanger 30 and a blower assembly 34. In some embodiments, the indoor HVAC unit 12B may also include a furnace 52, for example, when HVAC system 11 is not implemented to operate in a heat pump mode. In such embodiments, the furnace 52 may combust fuel, such as natural gas, to produce a combustion product, which may be flowed through tubing of a separate heat exchanger to facilitate injecting heat from the combustion product into supply air to be routed through ductwork 14 of the building 10.
In some embodiments, the supply air heat exchanger 30 may function as an evaporator when in a cooling mode and as a condenser when in a heating mode. Thus, as depicted, the indoor HVAC unit 12B and the outdoor HVAC unit 12C may be fluidly coupled via one or more refrigerant conduits 54 to form a refrigerant circuit (e.g., loop), for example, typically transferring primarily liquid refrigerant in one direction and primarily vaporized refrigerant in the opposite direction.
To help illustrate, an example schematic of a portion 60 of an HVAC unit 12 is shown in
As the refrigerant flows through the condenser 62, a first air flow 68 may be used to extract heat from refrigerant to facilitate condensing the vapor into liquid. When operating in a cooling mode, the first air flow 68 may be produced using environmental or outside air, for example, by actuating a fan 32. On the other hand, when operating in a heating mode, the first air flow 68 may be produced using supply air, for example, by actuating a blower assembly 34. Before being supplied to the evaporator 66, the refrigerant may flow through one or more expansion devices 64 to facilitate reducing pressure.
As the refrigerant flows through the evaporator 66, the refrigerant may undergo a phase change from liquid to vapor that facilitates extracting heat from a second air flow 70. When operating in a cooling mode, the second air flow 70 may be produced using supply air, for example, by actuating a blower assembly 34. On the other hand, when operating in a heating mode, the second air flow 70 may be produced using environmental or outside air, for example, by actuating a fan 32. Thereafter, the refrigerant may be circulated back to the compressor 40.
As depicted, the compressor 40 may be actuated by a motor 72 during operation. In some embodiments, the motor 72 may be a switched reluctance motor, an induction motor, an electronically commutated permanent magnet motor, and/or another suitable electromechanical motor. In other words, the motor 72 may actuate the compressor 40 when electrical power is supplied to the motor 72.
To facilitate controlling supply of electrical power to the motor 72, a variable speed drive (VSD) 74 and/or a control board 42 may be coupled to the motor 72. In particular, the variable speed drive 74 may receive alternating current (AC) electrical power having a fixed line voltage and a fixed line frequency from a power source, such as an electrical grid. Additionally, the control board 42 may control operation of the variable speed drive 74 to supply alternating current (AC) electrical power with a variable voltage and/or a variable frequency to the motor 72, for example, by controlling switching devices implemented in the variable speed drive 74. In other embodiments, the motor 72 may be powered directly from an AC power source or a direct current (DC) power source, such as a battery.
To facilitate controlling operation of the variable speed drive 74 or motor 72, as in the depicted embodiment, the control board 42 may include an analog to digital (A/D) converter 76, a microprocessor 78, non-volatile memory 80, and an interface 82. For example, to control switching in the variable speed drive 74, the microprocessor 78 may execute instructions stored in a tangible, non-transistor, computer readable medium, such as the non-volatile memory 80, to determine control signals or commands, which may be communicated to the variable speed drive 74 via the interface 82. Additionally, the control board 42 may control switching in the variable speed drive 74 based at least in part on feedback from the motor 72 and/or other sensors, for example, as analog electrical signals, which may be converted to digital data via the analog to digital (A/D) converter 76 before processing by the microprocessor 78.
In any case, it should be appreciated that any of the features described herein may be incorporated with the HVAC unit 12, a residential heating and cooling system, or other HVAC system. Additionally, while the features disclosed herein are described in the context of embodiments that directly heat and cool a supply air stream provided to a building or other load, embodiments of the present disclosure may be applicable to other HVAC systems as well. For example, the features described herein may be applied to mechanical cooling systems, free cooling systems, chiller systems, or other heat pump or refrigeration applications. In accordance with the present disclosure, any of the aforementioned HVAC systems, such as an RTU, may include a refrigerant leak detection assembly including various refrigerant leak detectors (e.g., sensors) configured to detect refrigerant leaked from a refrigerant loop or circuit (e.g., vapor compression loop or circuit) thereof. The refrigerant leak detectors (e.g., sensors) are selectively positioned within the HVAC system (e.g., RTU) to improve upon a timing and/or accuracy of refrigerant leak detection over traditional configurations. As an example, a refrigerant leak detector selectively positioned in any of the locations described in greater detail below may be configured to accurately detect a refrigerant leak within 5 minutes of the refrigerant leak occurring.
In the illustrated embodiment, the refrigerant leak detection assembly 102 includes refrigerant leak detectors 104, such as refrigerant leak sensors (e.g., refrigerant concentration sensors, thermal sensors, other types of sensors configured to detect a refrigerant leak, etc.) configured to detect refrigerant (e.g., low GWP refrigerant, such as A2L refrigerant) leaked from a portion of the RTU 100, such as from a refrigerant loop or circuit (e.g., vapor compression loop or circuit) thereof. The refrigerant leak detection assembly 102 also includes a controller 106 (including one or more controller components) in communication (e.g., wired or wireless communication) with the refrigerant leak detectors 104.
As shown, the controller 106 may include control circuitry 108, such as processing circuitry 110, memory circuitry 112, and an analog-to-digital (A-D) converter 114, among other possibly componentry. The controller 106 may also include a database 116 in certain embodiments, while in some embodiments, the database 116 is separate from the controller 106 and the controller 106 accesses the database 116 via wired or wireless communication techniques. The processing circuitry 110 may be implemented as a general-purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable electronic processing components.
The memory circuitry 112 (e.g., memory, memory unit, storage device, etc.) may include one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage, etc.) for storing data and/or computer code for completing or facilitating the various processes, layers and modules described in the present application. Additionally or alternatively, the memory circuitry 112 may be or include volatile memory or non-volatile memory. Additionally or alternatively, the memory circuitry 112 may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described in the present application. According to some embodiments, the memory circuitry 112 is communicably connected to the processing circuitry 110 and includes computer code for executing one or more processes described herein.
In some embodiments, the controller 106 is provided in a control board (e.g., the control board 42 in
As described above, the controller 106 and the refrigerant leak detectors 104 may be in wired or wireless communication with one another, such that the refrigerant leak detectors 104 may transmit sensor feedback (e.g., leak detection signals and/or data) via wired or wireless communication to the controller 106. For example, the controller 106 and the refrigerant leak detectors 104 may communicate with each other using a wireless technique including, but not limited to, Bluetooth technology, Wireless Fidelity (Wi-Fi), mobile communication technology, Infrared communication, etc. Suitable modules may be provided with the refrigerant leak detectors 104 and the controller 106 to facilitate wireless communication therebetween. In some embodiments, the controller 106 may include the A-D converter 116 for converting analog electrical signals received from the refrigerant leak detectors 104 to digital data before processing by the processing circuitry 110.
As described in greater detail below with reference to later drawings, the refrigerant leak detectors 104 (e.g., sensors) may be selectively distributed about various locations within the RTU 100. Locations of the refrigerant leak detectors 104 in accordance with the present disclosure may enable relatively accurate, fast, and reliable refrigerant leak detection. For example, locations of the refrigerant leak detectors 104 in accordance with the present disclosure may enable refrigerant leak detection within 5 minutes of the refrigerant leak occurring, may detect refrigerant leaks proximate critical locations of the RTU 100, etc. Additionally or alternatively, locations of the refrigerant leak detectors 104 may be configured to protect certain componentry of the RTU 100, such as electronic componentry, from negative effects that may otherwise occur when said componentry is contacted by unidentified leaked refrigerant. Additionally or alternatively, locations of the refrigerant leak detectors 104 may be configured to ensure identification of a refrigerant leak prior to the refrigerant leak reaching a space conditioned by the HVAC system (e.g., the RTU 100).
In some embodiments, the controller 106 is configured to determine, based on sensor feedback from the refrigerant leak detectors 104, an extent and/or location of the leaked refrigerant, an extent and/or location of the refrigerant leak, or both. In response to identifying a refrigerant leak and information associated with the refrigerant leak, the controller 106 may perform one or more actions, such as transmitting an alert (e.g., to a user interface 118 of the RTU 100 and/or to a separate device, such as a smart phone, a computer, a tablet, a server, cloud storage, etc.), controlling operation of a component (e.g., a compressor, an expansion valve, a blower or fan, a damper, etc.) of the RTU 100, etc. Controlling operation of the component may include, for example, changing a setting of the component, stopping operation of the component, initiating operation of the component, or any combination thereof.
It should be understood that the present disclosure encompasses embodiments having certain features in one embodiment (e.g., the first embodiment illustrated in
Referring first to
The RTU 200 also includes a return air chamber 238 (e.g., a return air section, a return air compartment, etc.) fluidly coupled a return air inlet 239 illustrated in
One or more filters 248 (e.g., a filter assembly) may be provided in the housing 220 for filtering return air and/or fresh air received in the housing 220. For example, the filters 248 may extend between return air chamber 238 and a blower chamber 250 (e.g., an air flow chamber) defined in the housing 220. Further, a first heat exchanger, such as an evaporator 252, is provided in the housing 220 for cooling air to be supplied to a conditioned space. The RTU 200 further includes one or more blowers 254 provided with a variable frequency drive (VFD) 256 and a motor 258 labeled in
The RTU 200 further includes a compressor 262, a second heat exchanger (e.g., a condenser 264 illustrated in
The fluid conduit 277 may be susceptible to refrigerant leaks at or near the brazed joint 281. Accordingly, the first refrigerant leak detector 204a and the second refrigerant leak detector 204b are disposed adjacent to the brazed joint, such as within six inches, one foot, two feet, or three feet of the brazed joint 281, such that any refrigerant leaked from the fluid conduit 277 at or adjacent to the brazed joint 281 is quickly identified. In some embodiments, the refrigerant leak detectors 204a, 204b are positioned underneath the fluid conduit 277 as the leaked refrigerant may tend to fall downardly toward the refrigerant leak detectors 204a, 204b. In some embodiments, as shown in
In some embodiments, the second refrigerant leak detector 204b may be disposed on a ledge 284 (e.g., bracket, mounting bracket, etc.) coupled to the panel 282. Additionally or alternatively, in some embodiments, the first refrigerant leak detector 204a, the second refrigerant leak detector 204b, or a third refrigerant leak detector may be disposed in and/or otherwise coupled to the drain pan 280, adjacent to (e.g., within six inches, one foot, two feet, or three feet of) any other brazed joint(s) associated with the fluid conduit 277 or an additional fluid conduit, etc.
While the first and second refrigerant leak detectors 204a, 204b are robustly illustrated in
In the illustrated embodiment, the control box 224 is separated into the low voltage compartment 232 receiving low voltage components and the high voltage compartment 234 receiving high voltage components, for example, by the bifurcating panel 236 (e.g., wall). The control board 222 may be distributed between the high voltage compartment 234 and the low voltage compartment 232 in certain embodiments, or the control board 222 may be disposed in one or the other. However, openings 310 through the panel 228 may enable leaked refrigerant from, for example, a chamber 312 corresponding to the evaporator 252 to migrate through the openings 310 and into the control box 224. The fifth refrigerant leak detector 204e may be disposed in the low voltage compartment 232 and the sixth refrigerant leak detector 204f may be disposed in the high voltage compartment 234, such that the fifth refrigerant leak detector 204e and/or the sixth refrigerant leak detector 204f can detect any such migratory refrigerant leaks.
As previously noted, embodiments of the present disclosure may include some but not all of the refrigerant leak detectors 204 described above. For example, described above with respect to various ones of
As previously described,
Further, the third refrigerant leak detector 404c may be positioned adjacent to (e.g., within six inches, one foot, two feet, or three feet of) a hairpin side 416 of the evaporator 406, and the first refrigerant leak detector 404a may be positioned adjacent to (e.g., within six inches, one foot, two feet, or three feet of) an expansion valve 418 of the RTU 400. In some embodiments, the hairpin side 416 of the evaporator 406 and/or the expansion valve 418 are susceptible to refrigerant leaks. The fourth refrigerant leak detector 404d may be positioned adjacent to a brazed joint 420 coupling two portions of a fluid conduit. In this way, refrigerant leaks from the hairpin side 416 of the evaporator 418, the expansion valve 418, and/or the brazed joint 420 may be quickly detected. Although not marked in the illustrated embodiment, as previously described, one or more refrigerant leak detectors may be disposed in, on, or adjacent to a drain pan underneath the evaporator 406. The fifth refrigerant leak detector 404c and the sixth refrigerant leak detector 404f may be positioned at, on, or adjacent to (e.g., within six inches, one foot, two feet, or three feet of) a bottom discharge 422 of the RTU 400, noting that in some embodiments, the RTU 400 may additionally or alternatively include a side and/or top discharge.
For example,
As similarly described above, the RTU 800 (e.g., housing 804) may include a return air section 812 (e.g., return air chamber, return air plenum), a blower section 814, a heating section 816, a control section 818, and an outdoor heat exchanger section 820 (e.g., condenser section). The housing 804 may define a return air inlet 822 configured to receive a return air flow (e.g., from a conditioned space) and direct the return air flow into the return air section 812. In some embodiments, the housing 804 may also be configured to direct an outdoor air flow into the return air section 812 (e.g., via an outdoor air inlet, via an economizer) and/or the housing 804 may be configured to discharge a portion of the air within the return air section 812 and the housing 804 as exhaust air (e.g., via an exhaust air outlet).
In any case, air within the return air section 812 may be directed to flow across (e.g., through) a filter assembly 824 having one or more filters 826 and a heat exchanger 828 (e.g., evaporator, heat exchange coil, cooling coil) disposed within the housing 804 between the return air section 812 and the blower section 814 (e.g., relative to a direction of air flow through the housing 804). More specifically, the blower section 814 may include one or more blowers 830 configured to draw the air flow from the return air section 812, across (e.g., through) the filter assembly 824 and the heat exchanger 828, and into the blower section 814. The heat exchanger 828 may operate as an evaporator and may transfer heat from the air flow to a working fluid circulated through the heat exchanger 828 in order to cool the air flow. The one or more blowers 830 may further force the air flow through the heating section 816 and out of the housing 804 via a supply air outlet 832. In some embodiments, the heating section 816 may include a heater (e.g., gas furnace, heating coil, electric heater) configured to transfer heat to the air flow within the heating section 816. In other embodiments, the heating section 816 may not include a heater, and the heating section 816 may instead be considered a supply air plenum of the housing 804.
As similarly described above, the control section 818 may include one or more components configured to enable supply of power and/or enable control of certain components of the RTU 800. For example, the control section 818 may include a control box portion 834 enclosing one or more controllers (e.g., control boards, control panels, control systems) configured to enable operational control of components of the RTU 800. In some embodiments, the control section 818 may include a variable frequency drive (VFD) section 836 configured to contain and enclose one or more VFDs, which may be configured to regulate operation of one or more compressors of the RTU 800. The one or more compressors may be disposed within the outdoor heat exchanger section 820 along with one or more outdoor heat exchangers (e.g., condensers) configured to enable transfer of heat between a working fluid circulated through the RTU 800 (e.g., a working fluid circuit) and an ambient air flow.
In accordance with the present techniques, the RTU 800 also includes the refrigerant leak detection sensor assembly 802, which may be an assembly of, and/or may include components of, an embodiment of the refrigerant leak detection assembly 102 described above. As shown, the refrigerant leak detection sensor assembly 802 is disposed within the blower section 814 of the RTU 800. The refrigerant leak detection sensor assembly 802 may be a refrigerant sensor assembly including a refrigerant detection sensor and a mounting bracket configured to retain and support the refrigerant detection sensor in a desired orientation within the RTU 800 in an installed configuration of the refrigerant leak detection sensor assembly 802. As described in further detail below, the refrigerant leak detection sensor assembly 802 is configured to be installed within the RTU 800 in a particular orientation (e.g., predetermined orientation) that enables more accurate and reliable operation of the refrigerant detection sensor (e.g., more accurate and reliable detection of leaked refrigerant) within the RTU 800. The present techniques also enable more reliable and repeatable installation of the refrigerant leak detection sensor assembly 802 in the particular or predetermined orientation within the RTU 800.
As described above, the blower 830 may be configured to draw an air flow across the heat exchanger 828 to place the air flow in a heat exchange relationship with a refrigerant (e.g., working fluid) directed through the heat exchanger 828. In the illustrated embodiment, the blower 830 is supported and suspended within the blower section 814 by a support frame 906, which may include one or more rails, braces, bars, brackets, panels, and/or other components to provide structural support for one or more components mounted to the support frame 906. The heat exchanger 828 may be disposed along a refrigerant circuit 908 (e.g., working fluid circuit) configured to circulate the refrigerant through the heat exchanger 828 and through other components (e.g., additional heat exchanger, compressor, expansion valve) disposed along the refrigerant circuit 906. At least a portion of the refrigerant circuit 906 (e.g., refrigerant conduit) may extend through the blower section 814 within the housing 804. In some embodiments, the heat exchanger 828 may be configured to operate as an evaporator to enable cooling of the air flow directed across the heat exchanger 828 via operation of the blower 830. During operation of the heat exchanger 828 as an evaporator, moisture within the air flow may condense to form condensate (e.g., water, liquid droplets). In some embodiments, the RTU 800 may include a condensate blowoff panel 910 configured to capture (e.g., block, divert, redirect) condensate formed via operation of the heat exchanger 828 and to direct the condensate toward a condensate drain pan of the RTU 800. For example, the condensate blowoff panel 910 may be attached to the support frame 906 described above.
In accordance with the present techniques, the refrigerant leak detection sensor assembly 802 is disposed within the blower section 814. The refrigerant leak detection sensor assembly 802 includes a refrigerant detection sensor 912 and a mounting bracket 914 to which the refrigerant detection sensor 912 is coupled (e.g., mounted, attached, secured). The refrigerant leak detection sensor assembly 802 may be retained within the blower section 814 in a desired orientation via engagement between the mounting bracket 914 and a retention bracket 916 disposed within the blower section 814 (e.g., housing 804). More specifically, the mounting bracket 914 and may be attached (e.g., mechanically secured) to the retention bracket 916 in an installed configuration of the refrigerant leak detection sensor assembly 802 within the blower section 814. For example, the retention bracket 916 may be attached to, and/or may be a component of, the support frame 906 described above. Details of the mounting bracket 914 and the retention bracket 916 are described further below.
As shown, in an installed configuration, the refrigerant leak detection sensor assembly 802 (e.g., refrigerant detection sensor 912, mounting bracket 914) may be disposed above (e.g., vertically above, relative to vertical axis 904) a conduit 918 (e.g., suction conduit, conduit segment, suction line) of the refrigerant circuit 906 extending within the blower section 814. For example, the conduit 918 may be a suction conduit of the refrigerant circuit 906, and the conduit 918 may be configured to direct refrigerant from the heat exchanger 828 (e.g., evaporator) to a compressor disposed along the refrigerant circuit 906. As will be appreciated, positioning the refrigerant leak detection sensor assembly 802 above (e.g., directly above, directly adjacent) the conduit 918 may enable more rapid and/or more reliable detection of refrigerant (e.g., vapor refrigerant) that may escape (e.g., leak) from the refrigerant circuit 906 via the refrigerant detection sensor 912. To enable mounting of the refrigerant leak detection sensor assembly 802 above (e.g., relative to vertical axis 904) the conduit 918, the retention bracket 916 may extend along the conduit 918 (e.g., along longitudinal axis 900) within the blower section 814. In some embodiments, the retention bracket 916 may be offset (e.g., laterally offset) from the conduit 918 along the lateral axis 902 to enable positioning of the refrigerant detection sensor 912 above (e.g., directly above, relative to vertical axis 904) the conduit 918 in an installed configuration of the refrigerant leak detection sensor assembly 802. Further, in some embodiments, the retention bracket 916 may be disposed beneath (e.g., relative to vertical axis 904) the condensate blowoff panel 910. Thus, in the installed configuration, the refrigerant leak detection sensor assembly 802 may also be disposed beneath (e.g., relative to vertical axis 904) the condensate blowoff panel 910. In this way, the condensate blowoff panel 910 may at least partially block inadvertent contact (e.g., exposure) between condensate formed during operation of the RTU 800 and the refrigerant detection sensor 912.
The mounting bracket 914 may include a mounting surface 950 (e.g., mounting platform, sensor platform, mounting portion) and a plurality of side flanges 952 extending from the mounting surface 950 (e.g., lateral edges of the mounting surface 950). The mounting bracket 914 may also include a mounting flange 954 extending from the mounting surface 950. In an assembled configuration, the refrigerant detection sensor 912 may be attached to the mounting surface 950. For example, the mounting surface 950 may include one or more apertures 956 (e.g., sensor mounting apertures) formed therethrough. Mechanical fasteners (e.g., screws, bolts, rivets, etc.) may extend through mounting apertures of the refrigerant detection sensor 912 and through the apertures 956 of the mounting surface 950 to fasten the refrigerant detection sensor 912 to the mounting surface 950. In some embodiments, the apertures 956 may be formed in a particular pattern or arrangement that enables mounting of the refrigerant detection sensor 912 to the mounting surface 950 in a single position or orientation (e.g., relative to the mounting bracket 914). For example, the apertures 956 may be formed through the mounting surface 950 in an arraignment that is off-center and/or asymmetrical relative to a centerline 958 (e.g., lateral centerline, relative to lateral axis 902) of the mounting surface 950. The apertures 956 may be configured to align with corresponding mounting apertures (e.g., mounting features) of the refrigerant detection sensor 912 in a desired assembled orientation of the refrigerant detection sensor 912 relative to the mounting bracket 914. In some embodiments, the apertures 956 may also be arranged to misalign with corresponding mounting apertures (e.g., mounting features) of the refrigerant detection sensor 912 in undesired or unintended orientations of the refrigerant detection sensor 912 relative to the mounting bracket 914. In this way, the arrangement of the apertures 956 may guide and enable proper assembly of the refrigerant leak detection sensor assembly 802.
The side flanges 952 and the mounting flange 954 may also guide and/or enable proper assembly of the refrigerant leak detection sensor assembly 802. More specifically, the side flanges 952 and the mounting flange 954 may be arranged to guide mounting of the refrigerant detection sensor 912 to the mounting surface 950 instead of, for example, to an inner surface of the mounting bracket 914 opposite the mounting surface 950. The side flanges 952 and the mounting flange 954 may cooperatively define a cavity 960 formed opposite the mounting surface 950. However, it may be undesirable to mount the refrigerant detection sensor 912 within the cavity 960. Accordingly, the side flanges 952, the mounting flange 954, and/or the apertures 956 may be arranged in a manner that blocks or inhibits securement of the refrigerant detection sensor 912 within the cavity 960. For example, upon arrangement of the refrigerant detection sensor 912 within the cavity 960 and with mounting apertures (e.g., mounting features) of the refrigerant detection sensor 912 in alignment with the apertures 956 of the mounting surface 950, coupling of one or more connectors (e.g., wires, cables) to the refrigerant detection sensor 912 may be blocked via the mounting flange 954 and/or one or more of the side flanges 952 (e.g., due to insufficient clearance between a connector receptible of the refrigerant detection sensor 912 and one of the side flanges 952 and/or mounting flange 954). Therefore, an installer may more readily appreciate that the refrigerant detection sensor 912 should be mounted to the mounting surface 950 (e.g., external to the cavity 960) to enable proper assembly of the refrigerant leak detection sensor assembly 802 and connection of the refrigerant detection sensor 912 to a corresponding connector.
The mounting flange 954 is also configured to enable more rapid and more reliable installation of the refrigerant leak detection sensor assembly 802 within the RTU 800. As mentioned above, the mounting bracket 914 may be configured to engage with the retention bracket 916 disposed within the housing 804 (e.g., blower section 814) of the RTU 800. For example, the mounting flange 954 may be disposed within a retention channel defined by the retention bracket 916 and may abut a retention surface of the retention bracket 916 in the installed configuration. To enable installation of the refrigerant leak detection sensor assembly 802 with the mounting bracket 914 and/or the refrigerant detection sensor 912 in a desired orientation within the RTU 800 (e.g., to facilitate proper operation of the refrigerant detections sensor 912), the mounting bracket 914 may include one or more features and/or characteristics that guides and facilitates proper installation of the refrigerant leak detection sensor assembly 802 in the desired orientation.
In the illustrated embodiment, the mounting flange 954 includes a first edge 962 (e.g., upper edge) and a second edge 964 (e.g., lower edge), opposite the first edge 962. The mounting flange 954 may define or include a first dimension 966 (e.g., height) extending from the first edge 962 to the second edge 964 (e.g., along the vertical axis 904). In some embodiments, the first dimension 966 may be approximately equal to or less than a corresponding dimension defined by the retention bracket 916. In this way, the mounting flange 954 may extend within a retention channel defined by the retention bracket 916 to facilitate proper installation of the refrigerant leak detection sensor assembly 802. In some embodiments, the first edge 962, the second edge 964, or both may be configured to abut one or more corresponding features of the retention bracket 916 to guide and facilitate installation of the refrigerant leak detection sensor assembly 802 in a desired orientation within the housing 804 of the RTU 800.
The mounting flange 954 may also include one or more mounting apertures 968 formed therethrough (e.g., along the lateral axis 902). In some embodiments, the mounting apertures 968 may be formed through the mounting flange 954 in an arrangement that facilitates securement of the mounting bracket 914 to the retention flange 916 in a desired orientation and blocks securement of the mounting bracket 914 to the retention flange 916 in an undesired orientation. For example, the mounting apertures 968 may be offset from a centerline 970 (e.g., vertically-centered line, relative to vertical axis 904, horizontal centerline) of the mounting bracket 954. Thus, the mounting apertures 968 may align with corresponding apertures formed in the retention bracket 916 in a desired orientation of the refrigerant leak detection sensor assembly 802 and may misalign with the corresponding apertures formed in the retention bracket 916 in an undesired orientation of the refrigerant leak detection sensor assembly 802. In this way, improper installation of the refrigerant leak detection sensor assembly 802 within the housing 804 of the RTU 800 may be inhibited, while proper installation of the refrigerant leak detection sensor assembly 802 in a desired orientation may be facilitated.
In an installed configuration, the mounting flange 954 of the mounting bracket 916 may abut the retention surface 982 of the retention bracket 916. Additionally, in some embodiments, the first edge 962 of the mounting flange 954 may abut the first retention flange 984, the second edge 964 of the mounting flange 954 may abut the second retention flange 986, or both. The retention surface 982 also includes mounting apertures 990 formed therethrough. The mounting apertures 990 of the retention surface 982 are configured and arranged to align with the mounting apertures 968 formed in the mounting flange 954 when the mounting bracket 914 is oriented in a desired orientation during installation of the refrigerant leak detection sensor assembly 802. The mounting apertures 990 may also be configured and arranged to misalign with the mounting apertures 968 of the mounting flange 954 when the mounting bracket 914 is oriented in an improper orientation during installation of the refrigerant leak detection sensor assembly 802. In this way, misalignment of the mounting apertures 968 and the mounting apertures 990 may inform an installer that the mounting bracket 914 is not properly oriented and/or arranged relative to the retention bracket 916 during installation of the refrigerant leak detection sensor assembly 802.
For example, in the illustrated embodiment, the refrigerant leak detection sensor assembly 802 is shown in a desired installed orientation relative to the retention bracket 916. Thus, the mounting apertures 990 of the retention bracket 916 and the mounting apertures 968 of the mounting flange 954 align with one another (e.g., along the lateral axis 902) and may be configured to receive corresponding mechanical fasteners to enable securement of the mounting bracket 914 to the retention bracket 916. In the proper orientation, the refrigerant detection sensor 912 is mounted to the mounting surface 950 (e.g., outer surface) of the mounting bracket 914 and extends away from the mounting surface 950 in a first direction 992 (e.g., along the vertical axis 904). The side flanges 952 of the mounting bracket 914 extend away from the mounting surface 950 in a second direction 994 (e.g., along the vertical axis 904), opposite the first direction 992. Additionally, the mounting flange 954 is in abutment with the retention surface 982, and the first edge 962 of the mounting flange 954 at least partially abuts the first retention flange 984 of the retention bracket 916. Accordingly, the mounting apertures 990 of the retention bracket 916 and the mounting apertures 968 of the mounting flange 954 align with one another to enable extension of mechanical fasteners therethrough to retain the refrigerant leak detection sensor assembly 802 in the installed configuration and in the desired orientation (e.g., first orientation, refrigerant detection sensor 802 generally extending and facing in the first direction 992, such as an upward direction relative to the vertical axis 904). However, if the orientation of the refrigerant leak detection sensor assembly 802 were inverted (e.g., 180 degrees) with respect to the vertical axis 904, and relative to the orientation showed in the illustrated embodiment, the refrigerant detection sensor 802 would generally extend and face the second direction 994 (e.g., second orientation, downward direction relative to the vertical axis 904). Such an orientation may be undesirable and may not enable proper operation of the refrigerant detection sensor 912. Accordingly, to block installation of the refrigerant leak detection sensor assembly 802 in the undesired orientation (e.g., second orientation), the mounting apertures 990 of the retention bracket 916 and the mounting apertures 968 of the mounting flange 954 may be misaligned with one another when the refrigerant leak detection sensor assembly 802 (e.g., mounting flange 954) is in the undesired orientation. Accordingly, the mounting apertures 990 of the retention bracket 916 and the mounting apertures 968 of the mounting flange 954 may not cooperatively accommodate and receive corresponding mechanical fasteners to enable securement of the mounting bracket 914 to the retention bracket 916 in the undesired orientation.
As described above, presently disclosed assemblies of refrigerant leak detection sensors enable more reliable and repeatable installation of refrigerant leak detection sensors in a desired location and orientation within the HVAC system. The embodiments described herein reduce, mitigate, and/or block improper installation of refrigerant leak detection sensors (e.g., in unintended locations, in unintended orientations) that may otherwise adversely affect intended operation of the refrigerant leak detection sensors to detect refrigerant leaks promptly, reliably, and effectively. In this way, the refrigerant leak detection sensors may be implemented with HVAC systems to detect refrigerant leaks relatively accurately, relatively reliably, and relatively quickly (e.g., within 5 minutes of onset of the refrigerant leak).
While only certain features and embodiments of the disclosure have been illustrated and described, many modifications and changes may occur to those skilled in the art, such as variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, including temperatures and pressures, mounting arrangements, use of materials, colors, orientations, and so forth without materially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the disclosure. Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not have been described, such as those unrelated to the presently contemplated best mode of carrying out the disclosure, or those unrelated to enabling the claimed disclosure. It should be noted that in the development of any such actual implementation, as in any engineering or design project, numerous implementation specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.
The techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function] . . . ” or “step for [perform]ing [a function] . . . ”, it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f).
This application is a continuation-in-part of U.S. patent application Ser. No. 18/784,720, entitled “ARRANGEMENT FOR REFRIGERANT LEAK MANAGEMENT,” filed Jul. 25, 2024, which claims priority to and the benefit of U.S. Provisional Application No. 63/528,855, entitled “ARRANGEMENT FOR REFRIGERANT LEAK MANAGEMENT,” filed Jul. 25, 2023, each of which is incorporated herein by reference in its entirety for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 63528855 | Jul 2023 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 18784720 | Jul 2024 | US |
| Child | 19176768 | US |
