Air flow monitoring system for HVAC&r system

Abstract

An air flow monitoring system for a heating, ventilation, and air conditioning (HVAC) system includes one or more sensors configured to detect data indicative of a velocity of an air flow directed through a blower of the HVAC system, and a controller configured to regulate operation of a heating unit of the HVAC system based on the data indicative of the velocity of the air flow directed through the blower.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from and the benefit of Provisional Application No. 63 / 755,831, entitled “AIR FLOW MONITORING SYSTEM FOR HVAC&R SYSTEM,” filed February 7, 2025, which is hereby incorporated by reference in its entirety for all purposes.BACKGROUND

[0002] 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.

[0003] The present disclosure relates generally to heating, ventilation, and / or air conditioning (HVAC) systems, such as a rooftop unit (RTU).

[0004] An HVAC system may be utilized to provide ventilation and / or to maintain air quality in a confined space, such as a commercial or a household building. An HVAC system may circulate a working fluid, such as a refrigerant, through a closed circuit (e.g., working fluid loop or circuit, vapor compression loop or circuit) including a compressor, a condenser, an expansion device, and an evaporator. The working fluid in the evaporator may be utilized to cool an air flow via thermal exchange to condition the confined space. Additionally, in certain cases, a heating unit (e.g., furnace, electric heater) may be utilized to heat an air flow via thermal exchange to condition the confined space.

[0005] However, traditional refrigerants possess certain drawbacks. For example, although such traditional refrigerants are effective coolants, they may have a global warming potential (GWP) that is greater than desired. Accordingly, certain HVAC systems may utilize alternative working fluids or refrigerants with a lower GWP, such as A2L refrigerants. However, use of such alternative working fluids may be associated with various rules, regulations, and / or operating standards. Accordingly, it is now recognized that improved HVAC systems and methods for facilitating and / or ensuring operation of HVAC systems utilizing alternative working fluids with associated rules, regulations, and / or operating standards are desired.SUMMARY

[0006] 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.

[0007] In an embodiment, an air flow monitoring system for a heating, ventilation, and air conditioning (HVAC) system includes one or more sensors configured to detect data indicative of a velocity of an air flow directed through a blower of the HVAC system, and a controller configured to regulate operation of a heating unit of the HVAC system based on the data indicative of the velocity of the air flow directed through the blower.

[0008] In another embodiment, a heating, ventilation, and air conditioning (HVAC) system includes a housing configured to receive an air flow, a blower assembly positioned within the housing and having one or more blowers, where the one or more blowers are configured to bias the air flow through the housing, a heating unit positioned within the housing and configured to transfer heat to the air flow directed through the housing, and an air flow monitoring system. The air flow monitoring system includes one or more sensor assemblies positioned within the housing and configured to detect data indicative of a flow rate of the air flow biased through the housing via the one more blowers, and a controller configured to control operation of the heating unit based on the data.

[0009] In another embodiment, a rooftop unit for a heating, ventilation, and air conditioning (HVAC) system includes a housing having a blower chamber, one or more blowers disposed within the blower chamber and configured to direct an air flow through the housing, and a heating unit positioned within the housing downstream of the blower chamber, relative to a flow direction of the air flow through the housing, where the heating unit is configured to heat the air flow during a heating mode of the HVAC system. The rooftop unit further includes one or more sensors coupled to the one or more blowers, where the one or more sensors are configured to detect data indicative of a velocity of the air flow, and a controller configured to compare the velocity to one or more threshold values, and adjust an amount of heat output by the heating unit based on a comparison of the velocity to the one or more threshold values.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[0011] FIG. 1 is a perspective view of an embodiment of a heating, ventilation, and / or air conditioning (HVAC) system for building environmental management that may employ one or more HVAC units, in accordance with aspects of the present disclosure;

[0012] FIG. 2 is a perspective view of an embodiment of an HVAC unit of the HVAC system of FIG. 1, in accordance with aspects of the present disclosure;

[0013] FIG. 3 is a perspective view of an embodiment of a residential split heating and cooling system, in accordance with aspects of the present disclosure;

[0014] FIG. 4 is a schematic view of an embodiment of a vapor compression system that may be used in an HVAC system, in accordance with aspects of the present disclosure;

[0015] FIG. 5 is a schematic view of an embodiment of an HVAC system configured as a rooftop unit (RTU) having an air flow monitoring system, in accordance with aspects of the present disclosure;

[0016] FIG. 6 is an isometric view of an embodiment of an HVAC system configured as an RTU having an air flow monitoring system, in accordance with aspects of the present disclosure;

[0017] FIG. 7 is an axial view of an embodiment of a blower of an RTU, in accordance with aspects of the present disclosure;

[0018] FIG. 8 is a side view of an embodiment of a blower of an RTU, in accordance with aspects of the present disclosure;

[0019] FIG. 9 is a perspective view of an embodiment of an air flow monitoring system having a pitot tube sensor assembly, in accordance with aspects of the present disclosure;

[0020] FIG. 10 is a cross-sectional view of an embodiment of a pressure port of a pitot tube sensor assembly, in accordance with aspects of the present disclosure;

[0021] FIG. 11 is a front schematic view of an embodiment of an air flow monitoring system having an anemometer sensor assembly, in accordance with aspects of the present disclosure;

[0022] FIG. 12 is a front view of an embodiment of an air flow monitoring system having a flow nozzle and piezometer ring sensor assembly, in accordance with aspects of the present disclosure; and

[0023] FIG. 13 is a perspective view of an embodiment of an air flow monitoring system having a flow nozzle and piezometer ring sensor assembly, in accordance with aspects of the present disclosure.DETAILED DESCRIPTION

[0024] 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.

[0025] 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.

[0026] 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.

[0027] The present disclosure relates to an air flow monitoring system of a heating, ventilation, and / or air conditioning (HVAC) system, such as a rooftop unit (RTU). More particularly, the present disclosure relates to a system for controlling aspects of an HVAC system based on detected operating conditions, thereby facilitating compliance with various operational standards associated with a particular working fluid employed by the HVAC system. For example, HVAC systems in accordance with the present disclosure may include low Global Warming Potential (GWP) working fluids (e.g., refrigerants), such as A2L refrigerants or A3 refrigerants, as a heat transfer medium (e.g., working fluid). Because low GWP working fluids (e.g., A2L refrigerants, A3 refrigerants) may be reactive (e.g., flammable), among other reasons, various rules, regulations, and operational standards may apply to HVAC systems utilizing such low GWP working fluids.

[0028] Accordingly, embodiments of the present disclosure are directed toward an air flow monitoring system (e.g., HVAC control system) configured to reduce and / or block combustion of a low GWP refrigerant (e.g., A2L refrigerant), thereby facilitating adherence to the various operational standards associated with low GWP refrigerants. The air flow monitoring system may include one or more sensors (e.g., air flow sensors, temperatures sensors, pressure sensors, sensor assemblies) configured to detect data indicative of an air flow velocity (e.g., air flow flowrate) across (e.g., through) a heating unit (e.g., electric resistance heater, furnace) of an HVAC system and communicate such data to a controller. The controller may then compare the data indicative of the air flow velocity to a threshold velocity (e.g., threshold flowrate). In response to a determination that the air flow velocity (e.g., detected air flow velocity, measured air flow velocity) is below the threshold velocity, the controller may activate one or more switches to disable or block the flow and / or modulate the flow of electricity and / or gas, such as natural gas, to the heating unit. For example, low air flow velocities or flowrates may be associated with decreased amounts of heat transfer from the heating unit, which may cause the heating unit to increase in temperature (e.g., to above a threshold temperature). By blocking and / or modulating (e.g., decreasing) the flow of electricity and / or gas to the heating unit, the air flow monitoring system may enable adherence to and / or compliance with various operational standards associated with low GWP refrigerants, while blocking and / or reducing combustion of the low GWP refrigerant (e.g., caused by exposure of the low GWP refrigerant to an overheated heating unit component).

[0029] Turning now to the drawings, FIG. 1 illustrates a heating, ventilation, and / or air conditioning (HVAC) system for building environmental management that may employ one or more HVAC units. In the illustrated embodiment, a building 10 is air conditioned by an HVAC system 11 that includes an HVAC unit 12. The building 10 may be a commercial structure or a residential structure. As shown, the HVAC unit 12 is disposed on the roof of the building 10; however, the HVAC unit 12 may be located in other equipment rooms or areas adjacent the building 10. The HVAC unit 12 may be a single package unit containing other equipment, such as a blower, integrated air handler, and / or auxiliary heating unit. In other embodiments, the HVAC unit 12 may be part of a split HVAC system, such as the system shown in FIG. 3, which includes an outdoor HVAC unit 58 and an indoor HVAC unit 56.

[0030] The HVAC unit 12 is an air-cooled device that implements a refrigeration cycle to provide conditioned air to the building 10. Specifically, the HVAC unit 12 may include one or more heat exchangers across which an air flow is passed to condition the air flow before the air flow is supplied to the building. In the illustrated 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. After the HVAC unit 12 conditions the air, the air is supplied to the building 10 via ductwork 14 extending throughout the building 10 from the HVAC unit 12. For example, the ductwork 14 may extend to various individual floors or other sections of the building 10. In certain embodiments, the HVAC unit 12 may be a heat pump that provides both heating and cooling to the building with one refrigeration circuit configured to operate in different modes. In other embodiments, the HVAC unit 12 may include one or more refrigeration circuits for cooling an air stream and a furnace for heating the air stream. A heat exchanger of the HVAC unit 12, such as one in a refrigeration circuit, may cause generation of condensate that is collected and removed in accordance with embodiments of the presently disclosed drain system and shield.

[0031] A control device 16, one type of which may be a thermostat, may be used to designate the temperature of the conditioned air. The control device 16 also may be used to control the flow of air through the ductwork 14. For example, the control device 16 may be used to regulate operation of one or more components of the HVAC unit 12 or other components, such as dampers and fans, within the building 10 that may control flow of air through and / or from the ductwork 14. In some embodiments, other devices may be included in the system, such as pressure and / or temperature transducers or switches that sense the temperatures and pressures of the supply air, return air, and so forth. Moreover, the control device 16 may include computer systems that are integrated with or separate from other building control or monitoring systems, and even systems that are remote from the building 10.

[0032] FIG. 2 is a perspective view of an embodiment of the HVAC unit 12. In the illustrated embodiment, the HVAC unit 12 is a single package unit that may include one or more independent refrigeration circuits and components that are tested, charged, wired, piped, and ready for installation. The HVAC unit 12 may provide a variety of heating and / or cooling functions, such as cooling only, heating only, cooling with electric heat, cooling with dehumidification, cooling with gas heat, or cooling with a heat pump. As described above, the HVAC unit 12 may directly cool and / or heat an air stream provided to the building 10 to condition a space in the building 10.

[0033] As shown in the illustrated embodiment of FIG. 2, a cabinet 24 encloses the HVAC unit 12 and provides structural support and protection to the internal components from environmental and other contaminants. In some embodiments, the cabinet 24 may be constructed of galvanized steel and insulated with aluminum foil faced insulation. Rails 26 may be joined to the bottom perimeter of the cabinet 24 and provide a foundation for the HVAC unit 12. In certain embodiments, the rails 26 may provide access for a forklift and / or overhead rigging to facilitate installation and / or removal of the HVAC unit 12. In some embodiments, the rails 26 may fit into “curbs” on the roof to enable the HVAC unit 12 to provide air to the ductwork 14 from the bottom of the HVAC unit 12 while blocking elements such as rain from leaking into the building 10.

[0034] The HVAC unit 12 includes heat exchangers 28 and 30 in fluid communication with one or more refrigeration circuits. Such heat exchangers may cause accumulation of condensate from environmental air that is addressed by embodiments of the presently disclosed drainage system. Tubes within the heat exchangers 28 and 30 may circulate a working fluid, such as R-410A, through the heat exchangers 28 and 30. The tubes may be of various types, such as multichannel tubes, microchannel tubes, conventional copper or aluminum tubing, and so forth. Together, the heat exchangers 28 and 30 may implement a thermal cycle in which the working fluid undergoes phase changes and / or temperature changes as it flows through the heat exchangers 28 and 30 to produce heated and / or cooled air. For example, the heat exchanger 28 may function as a condenser where heat is released from the working fluid to ambient air, and the heat exchanger 30 may function as an evaporator where the working fluid absorbs heat to cool an air stream. In other embodiments, the HVAC unit 12 may operate in a heat pump mode where the roles of the heat exchangers 28 and 30 may be reversed. That is, the heat exchanger 28 may function as an evaporator and the heat exchanger 30 may function as a condenser. In further embodiments, the HVAC unit 12 may include a furnace for heating the air stream that is supplied to the building 10. While the illustrated embodiment of FIG. 2 shows the HVAC unit 12 having two of the heat exchangers 28 and 30, in other embodiments, the HVAC unit 12 may include one heat exchanger or more than two heat exchangers.

[0035] The heat exchanger 30 is located within a compartment 31 that separates the heat exchanger 30 from the heat exchanger 28. Fans 32 draw air from the environment through the heat exchanger 28. Air may be heated and / or cooled as the air flows through the heat exchanger 28 before being released back to the environment surrounding the rooftop unit 12. A blower assembly 34, powered by a motor 36, draws air through the heat exchanger 30 to heat or cool the air. The heated or cooled air may be directed to the building 10 by the ductwork 14, which may be connected to the HVAC unit 12. Before flowing through the heat exchanger 30, the conditioned air flows through one or more filters 38 that may remove particulates and contaminants from the air. In certain embodiments, the filters 38 may be disposed on the air intake side of the heat exchanger 30 to prevent contaminants from contacting the heat exchanger 30.

[0036] The HVAC unit 12 also may include other equipment for implementing the thermal cycle. Compressors 42 increase the pressure and temperature of the working fluid before the working fluid enters the heat exchanger 28. The compressors 42 may be any suitable type of compressors, such as scroll compressors, rotary compressors, screw compressors, or reciprocating compressors. In some embodiments, the compressors 42 may include a pair of hermetic direct drive compressors arranged in a dual stage configuration 44. However, in other embodiments, any number of the compressors 42 may be provided to achieve various stages of heating and / or cooling. As may be appreciated, additional equipment and devices may be included in the HVAC unit 12, such as a solid-core filter drier, a drain pan, a disconnect switch, an economizer, pressure switches, phase monitors, and humidity sensors, among other things.

[0037] The HVAC unit 12 may receive power through a terminal block 46. For example, a high voltage power source may be connected to the terminal block 46 to power the equipment. The operation of the HVAC unit 12 may be governed or regulated by a control board 48. The control board 48 may include control circuitry connected to a thermostat, sensors, and alarms. One or more of these components may be referred to herein separately or collectively as the control device 16. The control circuitry may be configured to control operation of the equipment, provide alarms, and monitor safety switches. Wiring 49 may connect the control board 48 and the terminal block 46 to the equipment of the HVAC unit 12.

[0038] FIG. 3 illustrates a residential heating and cooling system 50, also in accordance with present techniques. The residential heating and cooling system 50 may provide heated and cooled air to a residential structure, as well as provide outside air for ventilation and provide improved indoor air quality (IAQ) through devices such as ultraviolet lights and air filters. In the illustrated embodiment, the residential heating and cooling system 50 is a split HVAC system. In general, a residence 52 conditioned by a split HVAC system may include working fluid conduits 54 that operatively couple the indoor unit 56 to the outdoor unit 58. The indoor unit 56 may be positioned in a utility room, an attic, a basement, and so forth. The outdoor unit 58 is typically situated adjacent to a side of residence 52 and is covered by a shroud to protect the system components and to prevent leaves and other debris or contaminants from entering the unit. The working fluid conduits 54 transfer working fluid between the indoor unit 56 and the outdoor unit 58, typically transferring primarily liquid working fluid in one direction and primarily vaporized working fluid in an opposite direction.

[0039] When the system shown in FIG. 3 is operating as an air conditioner, a heat exchanger 60 in the outdoor unit 58 serves as a condenser for re-condensing vaporized working fluid flowing from the indoor unit 56 to the outdoor unit 58 via one of the working fluid conduits 54. In these applications, a heat exchanger 62 of the indoor unit functions as an evaporator. Specifically, the heat exchanger 62 receives liquid working fluid, which may be expanded by an expansion device, and evaporates the working fluid before returning it to the outdoor unit 58.

[0040] The outdoor unit 58 draws environmental air through the heat exchanger 60 using a fan 64 and expels the air above the outdoor unit 58. When operating as an air conditioner, the air is heated by the heat exchanger 60 within the outdoor unit 58 and exits the unit at a temperature higher than it entered. The indoor unit 56 includes a blower or fan 66 that directs air through or across the indoor heat exchanger 62, where the air is cooled when the system is operating in air conditioning mode. Thereafter, the air is passed through ductwork 68 that directs the air to the residence 52. In accordance with present embodiments, the indoor unit 56 includes a drain system in accordance with the present disclosure to limit or block condensate generated by cooling of atmospheric air, for example, from entering the ductwork 68. The overall system operates to maintain a desired temperature as set by a system controller. When the temperature sensed inside the residence 52 is higher than the set point on the thermostat, or the set point plus a small amount, the residential heating and cooling system 50 may become operative to refrigerate additional air for circulation through the residence 52. When the temperature reaches the set point, or the set point minus a small amount, the residential heating and cooling system 50 may stop the refrigeration cycle temporarily.

[0041] The residential heating and cooling system 50 may also operate as a heat pump. When operating as a heat pump, the roles of heat exchangers 60 and 62 are reversed. That is, the heat exchanger 60 of the outdoor unit 58 will serve as an evaporator to evaporate working fluid and thereby cool air entering the outdoor unit 58 as the air passes over outdoor the heat exchanger 60. The indoor heat exchanger 62 will receive a stream of air blown over it and will heat the air by condensing the working fluid.

[0042] In some embodiments, the indoor unit 56 may include a furnace system 70. For example, the indoor unit 56 may include the furnace system 70 when the residential heating and cooling system 50 is not configured to operate as a heat pump. The furnace system 70 may include a burner assembly and heat exchanger, among other components, inside the indoor unit 56. Fuel is provided to the burner assembly of the furnace 70 where it is mixed with air and combusted to form combustion products. The combustion products may pass through tubes or piping in a heat exchanger, separate from heat exchanger 62, such that air directed by the blower 66 passes over the tubes or pipes and extracts heat from the combustion products. The heated air may then be routed from the furnace system 70 to the ductwork 68 for heating the residence 52.

[0043] FIG. 4 is an embodiment of a vapor compression system 72 that can be used in any of the systems described above and incorporates one or more drainage systems in accordance with present embodiments. The vapor compression system 72 may circulate a working fluid through a circuit starting with a compressor 74. The circuit may also include a condenser 76, an expansion valve(s) or device(s) 78, and an evaporator 80. The vapor compression system 72 may further include a control panel 82 that has an analog to digital (A / D) converter 83, a microprocessor 84, a non-volatile memory 85, and / or an interface board 86. The control panel 82 and its components may function to regulate operation of the vapor compression system 72 based on feedback from an operator, from sensors of the vapor compression system 72 that detect operating conditions, and so forth.

[0044] In some embodiments, the vapor compression system 72 may use one or more of a variable speed drive (VSDs) 87, a motor 88, the compressor 74, the condenser 76, the expansion valve or device 78, and / or the evaporator 80. The motor 88 may drive the compressor 74 and may be powered by the variable speed drive (VSD) 87. The VSD 87 receives alternating current (AC) power having a particular fixed line voltage and fixed line frequency from an AC power source, and provides power having a variable voltage and frequency to the motor 88. In other embodiments, the motor 88 may be powered directly from an AC or direct current (DC) power source. The motor 88 may include any type of electric motor that can be powered by a VSD or directly from an AC or DC power source, such as a switched reluctance motor, an induction motor, an electronically commutated permanent magnet motor, or another suitable motor.

[0045] The compressor 74 compresses a working fluid vapor and delivers the vapor to the condenser 76 through a discharge passage. In some embodiments, the compressor 74 may be a centrifugal compressor. The working fluid vapor delivered by the compressor 74 to the condenser 76 may transfer heat to a fluid passing across the condenser 76, such as ambient or environmental air 89. The working fluid vapor may condense to a working fluid liquid in the condenser 76 as a result of thermal heat transfer with the environmental air 89. The liquid working fluid from the condenser 76 may flow through the expansion device 78 to the evaporator 80.

[0046] The liquid working fluid delivered to the evaporator 80 may absorb heat from another air stream, such as a supply air stream 90 provided to the building 10 or the residence 52. For example, the supply air stream 90 may include ambient or environmental air, return air from a building, or a combination of the two. The liquid working fluid in the evaporator 80 may undergo a phase change from the liquid working fluid to a working fluid vapor. In this manner, the evaporator 80 may reduce the temperature of the supply air stream 90 via thermal heat transfer with the working fluid. Thereafter, the vapor working fluid exits the evaporator 80 and returns to the compressor 74 by a suction line to complete the cycle.

[0047] In some embodiments, the vapor compression system 72 may further include a reheat coil in addition to the evaporator 80. For example, the reheat coil may be positioned downstream of the evaporator relative to the supply air stream 90 and may reheat the supply air stream 90 when the supply air stream 90 is overcooled to remove humidity from the supply air stream 90 before the supply air stream 90 is directed to the building 10 or the residence 52.

[0048] It should be appreciated that any of the features described herein may be incorporated with the HVAC unit 12, the residential heating and cooling system 50, or other HVAC systems. 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.

[0049] As discussed below, any of the aforementioned HVAC systems, such as an RTU (e.g., HVAC unit 12), the residential heating and cooling system 50, and / or the vapor compression system 72, may utilize an air flow monitoring system including various sensors (e.g., sensor systems, sensor assemblies) configured to detect data indicative of an air flow velocity (e.g., air flow flowrate) across a heating unit (e.g., furnace, electric resistance heater) of the HVAC system and communicate such data to a controller. The controller may then compare the data indicative of the air flow velocity to a threshold velocity and may control components of the HVAC system (e.g., furnace, electric resistance heater) based on the comparison. As an example, in response to a determination that an air flow velocity through the heating unit of the HVAC system is below a threshold velocity, the controller may modulate and / or shut down operation of the heating unit, thereby reducing and / or blocking combustion of a low GWP refrigerant employed by the HVAC system.

[0050] With the preceding in mind, FIG. 5 is a schematic view of an embodiment of a rooftop unit (RTU) 100 (e.g., HVAC system) having an air flow monitoring system 102 (e.g., HVAC control system). Other possible features of various embodiments of the RTU 100 and / or the air flow monitoring system 102 will be described in greater detail with reference to later drawings. Further, while certain features of the air flow monitoring system 102 of the present disclosure are described with reference to an RTU, it should be understood that the present disclosure encompasses other types of HVAC systems (e.g., single package units, residential units, split systems, a combination thereof, and / or other types of HVAC systems) with the same or similar features of the air flow monitoring system 102 described herein.

[0051] In the illustrated embodiment, the air flow monitoring system 102 includes one or more sensors 104 (e.g., air flow flowrate sensors, air flow velocity sensors, temperature sensors, pressure sensors, sensor systems, sensor assemblies, pitot tube sensor assembly, anemometer sensor assembly, flow nozzle and piezometer ring sensor assembly) configured to detect data indicative of an air flow flowrate through and / or across components of the RTU 100, such as a heating unit of the RTU 100. The air flow monitoring system 102 also includes a controller 106 (e.g., including one or more controller components) in communication (e.g., wired or wireless communication) with the sensors 104 and configured to control aspects of the RTU 100 (e.g., control operation of the heating unit) based on sensor data received from the sensors 104, as discussed in greater detail below.

[0052] As shown, the controller 106 may include control circuitry 108, such as processing circuitry 110, memory circuitry 112 (e.g., memory device), and an analog-to-digital (A-D) converter 114, among other possible componentry. The controller 106 may also include a database 116 (e.g., memory, storage database) in certain embodiments. In some embodiments, the database 116 may be separate from the controller 106, and the controller 106 may be configured to access 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.

[0053] 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, 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.

[0054] In certain embodiments, the controller 106 is provided in a control board (e.g., control board 48, control panel 82) of the HVAC equipment (e.g., RTU 100). Although the control board 48 is illustrated proximal to the compressor(s) 42 in FIG. 2, for example, the control board 48 can be placed at any other suitable location. In certain embodiments, structure, logic, and / or functionality of the controller 106 may be embedded in the control board 48. Additionally, or alternatively, the controller 106 may be provided in a separate control box which can be positioned within the HVAC equipment or distant from the HVAC equipment. For example, the processing circuitry 110 or the database 116 may be provided in a cloud-based server, whereas other components may be provided in or near the HVAC equipment (e.g., RTU 100).

[0055] As described above, the controller 106 and the sensors 104 may be in wired or wireless communication with one another, such that the sensors 104 may transmit sensor feedback (e.g., temperature data, pressure data, air flow velocity data, sensor data) via wired or wireless communication to the controller 106. For example, the controller 106 and the sensors 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 sensors 104 (e.g., refrigerant sensor, refrigerant detection sensor) and the controller 106 to facilitate wireless communication therebetween. In some embodiments, the controller 106 may include the A-D converter 114 for converting analog electrical signals received from the sensors 104 to digital data before processing by the processing circuitry 110.

[0056] As described in greater detail below with reference to later drawings, embodiments of the sensors 104 may be selectively positioned about various locations within the RTU 100. Further, embodiments of the sensors 104 in accordance with the present disclosure may enable relatively accurate, fast, and reliable air flow velocity and / or air flow flowrate detection across and / or through components of the RTU 100. For example, as described in greater detail below, the RTU 100 may include a heating unit with one or more components (e.g., furnace, electric resistance heater) configured to heat an air flow. The RTU 100 may also include a blower assembly (e.g., supply fan assembly) having one or more blowers or fans configured to direct a flow of air across the heating unit of the RTU 100. Embodiments of the sensors 104 (e.g., sensor assemblies, sensor systems) discussed herein may be positioned proximate to the blower assembly, such as within an inlet cone or nozzle of a fan or blower of the blower assembly, thereby enabling the sensors 104 to detect data indicative of an air flow velocity across the heating unit of the RTU 100. Such data may be communicated to the controller 106, thereby enabling the controller 106 to perform one or more actions, such as controlling operation of a component (e.g., heating unit, compressor, blower assembly) of the RTU 100 and / or 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 the component may include, for example, suspending operation of the component, adjusting a setting of the component, initiating operation of the component, or any combination thereof.

[0057] For example, based on data detected from the sensors 104, the controller 106 may determine that an air flow velocity of an air flow directed across the heating unit of the RTU 100 is below a threshold velocity. In response to a determination that the air flow velocity is below the threshold velocity, the controller 106 may transmit a signal to stop operation of the heating unit of the RTU 100 and / or modulate (e.g., decrease) an amount of heat generated by the heating unit. For example, if the air flow velocity through the heating unit of the RTU 100 falls below a threshold velocity or setpoint, the temperature of components of the heating unit (e.g., electric resistance heaters, heat exchange tubes), or portions thereof, may increase above a threshold temperature or setpoint. In other words, insufficient air flow through the heating unit may reduce heat transfer from components of the heating unit, which may cause such components to increase in temperature above a threshold temperature or setpoint. Accordingly, monitoring the air flow velocity through the heating unit (e.g., via the sensors 104) may enable the controller 106 to shut down and / or modulate operation of the heating unit before the temperature of one or more components in the heating unit increases above a threshold temperature or setpoint. In this way, the air flow monitoring system 102 (e.g., the controller 106) may block or reduce combustion of a low GWP refrigerant, such as an A2L refrigerant, employed by the RTU 100. Additionally, or alternatively, in response to a determination that the air flow velocity is below the threshold velocity, the controller 106 may transmit a signal to increase a speed of a blower of the blower assembly (e.g., increase a rate of rotation of the fans or blowers or the blower assembly), thereby increasing the air flow flowrate and / or velocity. In this way, the increased air flow may limit the temperature of components of the heating unit (e.g., electric resistance heaters, heat exchange tubes), or portions thereof, from increasing above the threshold temperature or setpoint. It should be appreciated that different refrigerants may be associated with different threshold air flow velocities. For example, a particular lower limit of the air flow velocity associated with a particular refrigerant may be based on a lower flammability limit (LFL) of the refrigerant. Thus, refrigerants having different LFLs may be associated with different lower limit air flow velocity thresholds (e.g., minimum acceptable air flow velocity).

[0058] FIG. 6 is an isometric view of an embodiment of the RTU 100, including an embodiment of the air flow monitoring system 102 having the sensors 104. To facilitate discussion, the RTU 100 and components thereof, will be described below with reference to a longitudinal axis 97, a lateral axis 98, and a vertical axis 99. In the illustrated embodiment, the RTU 100 includes a housing 120 having a base 119 and a number of sides 121 that define an interior volume 122 of the housing 120. In certain embodiments, the sides 121 may be defined by one or more exterior panels 124 (e.g., walls). It should be appreciated that, in certain embodiments, one or more of the exterior panels 124 may correspond to removable access panels configured to be removed to provide access to the interior volume 122 of the housing 120. Additionally, the interior volume 122 may further be divided into sections and / or chambers by one or more interior panels 125 (e.g., walls). For example, as shown, a control board 126 (e.g., controller 106) is positioned in the housing 120 (e.g., within the interior volume 122) and includes electronic circuitry and one or more controllers configured to control devices (e.g., HVAC equipment, compressor, condenser, evaporator, damper, blower, etc.) provided in the housing 120. In certain embodiments, the control board 126 includes some or all of the componentry of the controller 106 illustrated in FIG. 5. The control board 126 may be disposed in a control box 128 (e.g., chamber, control box chamber, control enclosure), which may be defined in part by the housing 120 (e.g., by one or more of the sides 121 and / or exterior walls 124 of the housing 120) and / or in part by one or more of the interior panels 124 (e.g., walls) disposed within the housing 120. In certain embodiments, as shown in FIG. 6, the control board 126 may be positioned on a lateral side of the housing 120 along a length 130 of the housing 120 (e.g., where the length 130 of the housing 120 extends in a direction along the longitudinal axis 97, a width 132 of the housing 120 extends in a direction along the lateral axis 98, the length 130 is greater than the width 132, and a height 134 of the housing 120 extends in a direction substantially parallel to the vertical axis 99).

[0059] In the illustrated embodiment, the RTU 100 includes an air intake chamber 135 fluidly coupled to one or more inlets, thereby enabling the air intake chamber 135 to receive one or more air flows, such as a fresh (e.g., outdoor) air flow and / or a return air flow. For example, the RTU 100 may include a return air inlet (not shown) configured to enable return air to enter the housing 120 and a fresh air inlet 136 configured to enable fresh air to enter the housing 120. In certain embodiments, the return air inlet may be defined at least in part by the base 119 of the RTU 100. The fresh air inlet 136 may be defined at least in part by one or more of the exterior panels 124. In certain embodiments, the fresh air inlet 136 may include one or more collapsible hoods 137 (e.g., collapsible rain hoods) configured to block the fresh air inlet 136, thereby limiting exposure of the interior volume 122 of the RTU 100 to environmental conditions. In certain embodiments, the air intake chamber 135 may be divided into a first portion 139 (e.g., first sub-chamber) and a second portion 141 (e.g., second sub-chamber) via one or more of the interior panels 125. In certain embodiments, the first portion 139 may be fluidly coupled to the return air inlet and the second portion 141 may be fluidly coupled to the fresh air inlet 136.

[0060] In certain embodiments, one or more filters 138 (e.g., a filter assembly) may be provided within the interior volume 122 to filter return air and / or fresh air received in the housing 120. For example, the filters 138 may be positioned between the air intake chamber 135 and a blower chamber 140 (e.g., an air flow chamber) defined in the housing 120. In certain embodiments, the filters 138 may extend in one or more directions across the housing 120. For example, the filters 138 may extend in a direction (e.g., horizontal direction) along the lateral axis 98 from a first side 121 (e.g., first lateral side) of the housing 120 to a second side 121 (e.g., second lateral side) of the housing 120, and in a direction (e.g., vertical direction) along the vertical axis 99 from the base 119 of the housing to a third side 121 (e.g., roof) of the housing 120. Said another way, the filters may extend across a lateral dimension of the housing 120 (e.g., across the width 132 of the housing 120) and / or across a vertical dimension of the housing 120 (e.g., across the height 134 of the housing 120).

[0061] As shown in the illustrated embodiment, a first heat exchanger, such as an evaporator 142, is provided in the housing 120 and is configured to cool air (e.g., fresh air and / or return air) to be supplied to a conditioned space. The RTU 100 further includes a blower assembly 144 (e.g., fan assembly) having one or more blowers 145 (e.g., fans, direct drive plenum fans). Each of the blowers 145 may be provided with a variable frequency drive (VFD) and a motor, where the blowers 145 and the corresponding VFD(s) and motor(s) of the blower assembly 144 are disposed in the blower chamber 140. The blowers 145 of the blower assembly 144 generate an air flow to draw air through the air intake chamber 135 and supply conditioned air (e.g., after passing over the evaporator 142). In certain embodiments, the evaporator 142 is at least partially enclosed within an evaporator chamber 146 in the housing 120. In certain embodiments, the evaporator chamber 146 may be positioned within the housing 120 downstream of the filters 138 (and the air intake chamber 135) and upstream of the blower chamber 140 relative to a flow direction 160 (e.g., first flow direction) of an air flow directed through the housing 120 (e.g., via operation of the blower assembly 144). Thus, the evaporator 142 may be positioned upstream of the blowers 145, thereby enabling the blowers 145 to draw the air flow across the evaporator 142 (e.g., in the direction 160). It should be understood that, in general, the various chambers within the interior volume 122 may be separated (e.g., partially or wholly separated) from each other via the interior panels 125 of the RTU 100, as previously described.

[0062] The RTU 100 further includes a condensing section or chamber 148 having a second heat exchanger, such as a condenser 149 having one or more condenser coils, and condenser fans 150 provided proximal to each other. In certain embodiments, the heat exchanger (e.g., condenser 149, condensing units of the condenser 149) and the condenser fans 150 disposed within the condensing section 148 may be configured to cool a working fluid (e.g., low GWP refrigerant) directed through the RTU 100 before returning the working fluid to the evaporator 142 for conditioning the air flow directed through the evaporator chamber 146, as described above. To circulate the working fluid through the RTU 100, the RTU 100 may include a compressor 152 provided proximal to the heat exchanger (e.g., condenser 149) of the condensing section 148. The RTU 100 may also include, in certain embodiments, an economizer 154 and a powered exhaust 156 (e.g., exhaust fan).

[0063] Further still, the RTU 100 may include a heating section 158 (e.g., heating chamber) having a heating unit 159 (e.g., furnace system, gas heat exchanger, electric resistance heater, heating section) disposed therein and configured to supply heat to a conditioned air. For example, during operation of the RTU 100, an air flow (e.g., return air and / or fresh air) may generally be directed and / or drawn through the RTU 100 (e.g., via the blower assembly 144) in the first flow direction 160 (e.g., horizontal direction) along the longitudinal axis 97 from the air intake chamber 135, through the evaporator chamber 146, through the blower chamber 140, and across the heating unit 159 disposed within the heating section 158. After being directed across heating elements of the heating unit 159 (e.g., via operation of the blowers 145 of the blower assembly 144), the air flow may be discharged from the RTU 100 in a second direction 162 (e.g., vertically downward direction) along the vertical axis 99 toward a conditioned space. Thus, the heating section 158 (e.g., the heating unit 159) may be positioned downstream of the blower section 140 (e.g., blower assembly 144) relative to the direction 160 such that air exiting the blower section 140 (e.g., air discharged from the blowers 145 of the blower assembly 144) is directed across and / or through the heating unit 159 disposed within the heating section 158. The heated air may then be routed (e.g., in the direction 160) from the heating section 158 toward one or more additional filters 164 (e.g., a filter assembly) before being discharged out of a discharge section 166 (e.g., supply air section) toward the conditioned space in the direction 162. For example, the base 119 of the housing 120 may at least partially define a discharge outlet 167 within the discharge section 166, thereby enabling the air flow to be discharged from the RTU 100 in the direction 162 and directed toward a conditioned space (e.g., via ductwork coupled to the discharge outlet).

[0064] In certain embodiments, the heating unit 159 disposed within the heating section 158 may be a gas-fired heating unit 168 (e.g., staged gas heating unit, modulating gas heating unit) having one or more heating components configured to provide heat to the air flow directed through the heating section 158. For example, the gas-fired heating unit 168 may include one or more burner assemblies 170, one or more heat exchange tubes 172 (e.g., heating elements), and one or more draft inducer blowers 174, among other components. The one or more burner assemblies 170 may be configured to combust a fuel (e.g., natural gas) to generate combustion products, which may be directed and / or drawn through the heat exchange tubes 172 via operation of the one or more draft inducers 174. Thus, during operation of the gas-fired heating unit 168 (e.g., when the RTU 100 is operating in a heating mode), the combustion products generated via operation of the one or more burner assemblies 170 may pass through the heat exchange tubes 172 (e.g., piping), such that air directed across the heat exchange tubes 172 (e.g., via operation of the blower assembly 144) absorbs heat from the combustion products. In certain embodiments, the gas-fired heating unit 168 may include multiple combustion stages 176, and each combustion stage 176 may include a burner assembly 170, one or more heat exchange tubes 172, and a draft inducer 174. In this way, the gas-fired heat exchanger 168 may be operated (e.g., via the controller 106) to incrementally adjust heat output by selectively operating one or more of the combustion stages 176. Said another way, each of the combustion stages 176 of the gas-fired heating unit 168 may be selectively controllable (e.g., independently controllable), thereby enabling variable thermal output (e.g., based on a heating demand associated with the RTU 100, based on a detected air flow velocity or flowrate of the air flow directed across the heating unit 168).

[0065] In other embodiments, the heating unit 159 disposed within the heating section 158 may be an electric resistance heating unit 178 having one or more electric resistance heating elements 180 (e.g., resistive elements, heating wires, heating coils, heating ribbons) configured to provide heat to the air flow directed through the heating section 158 (e.g., directed across the heating elements 180 of the electric resistance heating unit 178). For example, the electric resistance heating unit 168 may include a power supply 182 configured to provide electrical energy to the heating elements 180 of the electric resistance heating unit 178, and the heating elements 180 may be configured to convert the electrical energy into thermal energy, thereby enabling the electric resistance heating unit 178 to heat the air flow for the conditioned space (e.g., when the RTU 100 is operating in a heating mode). In certain embodiments, the electric resistance heating unit 178 may include multiple heating elements 180 that are independently controllable, thereby enabling the electric resistance heating unit 178 to incrementally adjust heat output (e.g., by selectively operating one or more of the heating elements 180). Said another way, the heating elements 180 may be selectively controllable, thereby enabling variable thermal output. Additionally, or alternatively, the power supply 182 may be controlled (e.g., via the controller 106) to modulate (e.g., adjust) an amount of electrical power delivered to the one or more heating elements 180, thereby enabling variable thermal output (e.g., based on a heating demand associated with the RTU 100, based on a detected air flow velocity or flowrate of the air flow directed across the heating unit 168).

[0066] During operation of the RTU 100, if an air flow velocity or flowrate of the air flow directed across the heating unit 159 (e.g., gas-fired heating unit 168, electric resistance heating unit 178) falls below a threshold velocity or flowrate, the temperature of components of the heating unit 159 (e.g., heat exchange tubes 172 of the gas-fired heating unit 168, electric resistance-heating coils 180 of the electric resistance heating unit 178) may increase above a threshold temperature or setpoint. In other words, insufficient airflow through the heating unit 159 reduces heat transfer from components of the heating unit 159, which may cause such components to increase in temperature (e.g., to above a threshold temperature or setpoint). Accordingly, monitoring the air flow velocity of an air flow directed across the heating unit 159 may enable a controller (e.g., the controller 106, control board 126) to perform one or more actions that block and / or reduce combustion of a refrigerant (e.g., a low GWP refrigerant, such as an A2L refrigerant) employed by the RTU 100.

[0067] To this end, the RTU 100 may include the air flow monitoring system 102 discussed above having the sensors 104 (e.g., sensor system, sensor assemblies). As shown in the illustrated embodiment, embodiments of the sensors 104 discussed herein may be positioned within the blower chamber 140. More particularly, embodiments of the sensors 104 discussed herein may be positioned within an inlet cone or nozzle of one or more of the blowers 145 of the blower assembly 144 of the RTU 100 and may be configured to measure data indicative of an air flow velocity or flowrate through the blower chamber 140 (e.g., through the blowers 145 of the blower assembly 144). For example, the sensors 104 may be configured to measure data indicative of a temperature, a pressure, and / or a direction of an air flow through the blowers 145, and such data may be used by the controller 106 to calculate an estimated air flow velocity of the air flow directed across the heating unit 159. For example, the controller 106 may include software instructions stored thereon that are configured to calculate an estimated air flow velocity of an air flow directed across the heating unit 159 based on detected sensor data measurements from the sensors 104. In response to determining that the air flow velocity of the air flow directed across the heating unit 159 is below a threshold velocity, the controller 106 may perform one or more actions (e.g., stopping operation of a component of the RTU 100, changing a setting of a component of the RTU 100, initiating operation of a component of the RTU 100) configured to reduce a temperature of the heating unit 159, thereby blocking and / or reducing combustion of a refrigerant (e.g., a low GWP refrigerant, such as A2L) employed by the RTU 100. It should be appreciated that the controller 106 may be configured to compare the detected air flow velocity with a number of different thresholds and adjust operation of the heating unit 159 accordingly. For example, in response to a determination that the air flow velocity is below a first threshold value, the controller 106 may decrease an amount of heat output by the heating unit 159 by a first amount. In response to a determination that the air flow velocity is below a second threshold value, where the second threshold value is less than the first threshold value, the controller 106 may decrease the amount of heat output by the heating unit 168 by a second amount, where the second amount is greater than the first amount. In this way, the controller 106 may regulate an amount of heat output by the heating unit 159 based on a comparison of the detected velocity of the air flow through the blower assembly 144 to various threshold values. In certain embodiments, based on the velocity of the air flow falling below a lower limit threshold value, the controller 106 may suspend operation of the heating unit 159 (e.g., to block the heating unit 159 from outputting heat).

[0068] In certain embodiments (e.g., embodiments in which the heating unit 159 is a gas-fired heating unit 168), the controller 106 (e.g., control board 126) may control a position of one or more valves to block and / or regulate (e.g., decrease, suspend) the flow of fuel to one or more of the burner assemblies 170 and / or the flow of combustion products into the heat exchange tubes 172. Additionally, or alternatively, the controller 106 may be configured suspend operation of one or more of the burner assemblies 170 and / or one or more of the draft inducers 174. Thus, the controller 106 may be configured to regulate (e.g., control, reduce) a temperature of the heating unit 168 by controlling an amount of combustion products generated and / or directed through the heat exchange tubes 172 of the heating unit 168 (e.g., via control of the valves, the burner assemblies 170, and / or the draft inducers 174). It should be appreciated that the controller 106 may be configured to control operation of each of the combustion stages 176 (e.g., and the components thereof) independently, thereby enabling the controller 106 to incrementally adjust the temperature of the heating unit 168 (e.g., based on a detected air flow velocity of the air flow directed through the blower assembly 144). For example, the controller 106 may be configured to suspend operation of a first combustion stage 176 to reduce the temperature of the heating unit 168 by a first amount, and subsequently suspend additional stages 176 (e.g., in a sequence) to progressively decrease the temperature of the heating unit 168 (e.g., based on a comparison of the flow rate or velocity to various threshold values). The controller 106 may be configured to iterate through each of the combustion stages 176 until operation of the heating unit 168 is suspended (e.g., such that all combustion stages 176 are inoperative or suspended).

[0069] In other embodiments (e.g., embodiments in which the heating unit 159 is an electric resistance heating unit 178), the controller 106 (e.g., control board 126) may control the power supply 182 (e.g., activate one or more switches of the power supply 182) to deactivate one or more of the heating elements 180 (e.g., electric resistance heating coils) in the heating unit 159, thereby reducing a temperature of the heating unit 159. Additionally, or alternatively, the controller 106 may control the power supply 182 to modulate (e.g., adjust, regulate, decrease) an amount of electrical power delivered to one or more of the heating elements 180, thereby decreasing a temperature of the heating elements 180, which in turn, may decrease a temperature of the heating unit 178. Thus, the controller 106 may be configured to regulate (e.g., control, reduce) a temperature of the heating unit 178 by controlling a number of heating elements 180 in operation and / or by regulating an amount of electrical power provided to the one or more heating elements 180 (e.g., via control of the power supply 182). It should be appreciated that the controller 106 may be configured to control operation of each of the heating elements (e.g., suspend operation of each of the heating elements 180, regulate an amount of electrical power provided to each of the heating elements 180) independently, thereby enabling the controller 106 to incrementally adjust the temperature of the heating unit 178. For example, the controller 106 may be configured to suspend operation of a first heating element 180 to reduce the temperature of the heating unit 178 by a first amount, and subsequently suspend additional heating elements 180 (e.g., in a sequence) to progressively decrease the temperature of the heating unit 178. Additionally, or alternatively, the controller 106 may be configured to progressively decrease an amount of electrical power supplied to a particular heating element 180, thereby decreasing the amount of heat output by the particular heating element 180. The controller 106 may be configured to control remaining heating elements 180 in a similar manner, thereby enabling variable heat output from the heating unit 178.

[0070] Additionally or alternatively, the controller 106 may control operation of the blower assembly 144 to increase a speed of the blowers 145 (e.g., via increasing a frequency supplied to the VFD(s)) of the blower assembly 144, thereby increasing a flow rate and / or velocity of an air flow directed across the heating unit 159, which in turn, may reduce a temperature of the heating unit 159 (e.g., via increased heat exchange from the increased air flow). In certain embodiments, the controller 106 may be configured to maintain and / or increase a speed of the blowers 145 such that the air flow velocity is maintained above the threshold velocity. For example, upon determining that the air flow velocity is approaching the threshold velocity (e.g., is within a threshold deviation or range of the threshold velocity or flow rate), the controller 106 may proactively increase a speed of the blowers 145, thereby increasing the air flow velocity across the heating unit 159. In this way, the air flow velocity may be maintained above the threshold velocity, such that shutdown of certain components of the RTU 100 (e.g., heating unit 159) may be avoided. In certain embodiments, the controller 106 may send or transmit an alert (e.g., to the user interface 118 and / or to a separate device) with a recommendation to perform one or more of the actions described above.

[0071] It should be appreciated that, while each of the blowers 145 is illustrated as having a sensor 104 (e.g., sensor assembly) disposed therein (e.g., disposed within an inlet cone or nozzle of the blower 145), in certain embodiments, a single blower 145 may include the sensor 104 and / or one or more of the blowers 145 may share sensor (e.g., sensor assembly) components, and the controller 106 may be configured to calculate (e.g., average, interpolate) the air flow velocity across the heating unit 159 based on the sensor data from the sensor 104. For example, in certain embodiments, each of the blowers 145 may be operated at the same speed, and thus, sensor data associated with operation of one blower 145, which is indicative of an air flow flowrate through the respective blower 145, may be representative of an air flow flowrate through another blower 145 of the blower assembly 144 that is operated at the same speed as the first blower 145. Additionally, a cross-sectional area of a section containing the heating unit 159 may be known, thereby enabling the controller 106 to calculate the average air velocity of an air flow across or through the heating unit 159 (e.g., based on the volumetric flow rate through the blowers 145 as detected by the sensors 104 and the cross-sectional area of the section containing the heating unit 159). Further, it should be appreciated that positioning of components of the RTU 100 described herein is only for explanation purposes, and the present disclosure is not limited to the aforementioned positions of said components. The components can be arranged in any other suitable way in other embodiments.

[0072] FIGS. 5 and 6, described in detail above, are examples of the RTU 100 having the air flow monitoring system 102 with the sensors 104 and control componentry (e.g., controller 106, control board 126), among other components (e.g., blower assembly 144, blowers 145, heating unit 159). FIGS. 7 and 8, described below, are examples of an embodiment of a blower 145 of the RTU 100 that may include components (e.g., sensors 104) of the air flow monitoring system 102 mounted therein and / or associated therewith . FIGS. 9 and 10 illustrate a first embodiment of the air flow monitoring system 102 of FIG. 5, FIG. 11 illustrates a second embodiment of the air flow monitoring system 102 of FIG. 5, and FIGS. 12 and 13 illustrate a third embodiment of the air flow monitoring system 102 of FIG. 5. For purposes of clarity, the first embodiment of the air flow monitoring system 102 is labeled with reference numeral 202 in FIGS. 9 and 10 and includes a pitot tube sensor assembly 204, the second embodiment of the air flow minoring system 102 is labeled with reference numeral 302 in FIG. 11 and includes an anemometer sensor assembly 304, and the third embodiment of the air flow monitoring system 102 is labeled with reference numeral 402 in FIGS. 12 and 13 and includes a flow nozzle and piezometer ring sensor assembly 404.

[0073] It should be understood that the present disclosure encompasses embodiments having certain features from one embodiment (e.g., the first embodiment illustrated in FIGS. 9 and 10) and certain features from another embodiment (e.g., the second embodiment illustrated in FIG. 11 and / or third embodiment illustrated in FIGS. 12 and 13). Any such suitable combination of any such suitable features is contemplated herein. Further, while the controller 106 of FIG. 5 and / or the control board 126 of FIG. 6 is not labeled in FIGS. 9-13, it should be understood that the controller 106 and / or control board 126 may be included in such embodiments and may be communicatively coupled to each of the sensor assemblies 204, 304, 404 described herein. As previously described, certain instances of the present disclosure describe features of the air flow monitoring system 102 with respect to an RTU configured to utilize a low GWP refrigerant (e.g., A2L refrigerant), although it should be understood that the same or similar features of the air flow monitoring system 102 may be incorporated with other types of HVAC systems.

[0074] Further, as noted above, each of the embodiments of the air flow monitoring system 102 (e.g., air flow monitoring system 202, air flow monitoring system 302, air flow monitoring system 402) may include components (e.g., sensors 104, components of the pitot tube sensor assembly 204, components of the anemometer sensor assembly 304, components of the flow nozzle and piezometer ring sensor assembly 404) associated with a blower 145, such as disposed within an inlet cone of the blower 145 of the blower assembly 144. For example, as shown in FIGS. 7 and 8, each of the blowers 145 employed by the RTU 100 may correspond to a direct drive plenum fan having an inlet cone 184 coupled to an inlet panel (e.g., interior panel 125). In certain embodiments, a supply fan 186 (e.g., fan wheel) may be coupled to the inlet cone 184, a motor 188 may coupled to the supply fan 186, and a variable frequency drive (VFD) 190 may be coupled to the motor 188. As the fan wheel 186 rotates (e.g., via operation of the VFD 190 and the motor 188), air may be drawn through the inlet cone 184 and may exit the fan wheel 186 before being directed to an area (e.g., heating section 158) in which the air may be heated (e.g., by the heating unit 159). The inlet cone 184 may include a first end 192 (e.g., upstream end, face, mouth, upstream edge) coupled to the panel 125, a second end 194 (e.g., downstream end, throat, downstream edge) coupled to the fan wheel 186, and a body 196 that extends between the first end 192 and the second end 194 to define a passage 198 configured to receive the air flow drawn through the blower 145. In certain embodiments, a cross-sectional area of the inlet cone 184 (e.g., passage of the inlet cone) progressively decreases from the first end 192 to the second end 194 (e.g., cross-sectional area of the inlet cone 184 progressively decreases relative to the direction 160 along the longitudinal axis 97). In this way, the inlet cone 184 of the blowers 145 may serve as a flow nozzle to direct air toward the heating unit 159.

[0075] As discussed in greater detail below, components of the sensors 104 discussed herein (e.g., components of the pitot tube sensor assembly 204, components of the anemometer sensor assembly 304, components of the flow nozzle and piezometer ring sensor assembly 404) may be disposed within, positioned within, and / or in fluid communication with the passage 198 defined by the inlet cone 184 to facilitate collection of data indicative of an air flow velocity of an air flow directed through the blowers 145 (e.g., and across the heating unit 159).

[0076] Turning to FIG. 9, a perspective view of an embodiment of the air flow monitoring system 202 including the pitot tube sensor assembly 204 is shown. In the illustrated embodiment, the pitot tube sensor assembly 204 is disposed within the inlet cone 184 of a blower 145. More particularly, components of the pitot tube sensor assembly 204 may be positioned within the passage 198 defined by the inlet cone 184 proximate (e.g., within a threshold distance of) the second end 194 (e.g., throat) of the inlet cone 184 (e.g., at a position of the inlet cone having the smallest cross-sectional area). The pitot tube sensor assembly 204 may be configured to detect data indicative of an air flow velocity through the blower 145 and communicate such data to the controller 106, thereby enabling the controller 106 to control aspects of the RTU 100, as discussed above.

[0077] For example, the pitot tube sensor assembly 204 may include one or more probes 206 configured to detect data indicative of an air flow velocity of an air flow directed through the blower 145. As illustrated, the probes 206 may extend across the passage 198 of the inlet cone 184 in a direction (e.g., vertical direction) along the vertical axis 99. It should be appreciated, however, that the probes 206 may be arranged in other configurations. For example, in certain embodiments, a probe 206 may be disposed around a circumference of the second end 194 of the inlet cone, while in other embodiments, the probes 206 may extend in a direction (e.g., horizontal direction) along the lateral axis 98 and / or may extend diagonally across the passage 198 of the inlet cone 184.

[0078] Each of the probes 206 may include one or more sensing ports 208 (e.g., pressure ports) disposed and / or contained within an exterior surface of the probes 206. The sensing ports 208 may be formulated and / or positioned along the probe 206 on a concentric area basis. The sensing ports 208 of the probes 206 operate on the principle of a multi-point, self-averaging pitot tube to measure total pressure and static pressure components of an air flow directed through the blower 145. For example, as illustrated in FIG. 10, each of the sensing ports 208 may include a total pressure sensing port 210 having a chamfered opening or entrance 211, and a pair of static pressure sensing ports 212 offset from the total pressure sensing port 210. The chamfered opening or entrance 211 may be configured to limit air direction effects within the blower 145.

[0079] Each of the total pressure sensing ports 210 of the sensing ports 208 may be positioned on an upstream edge (e.g., leading edge) of the probe 206 relative to the direction 160 of an air flow through the blower 145. That is, each of the total pressure sensing ports 210 may be oriented in a direction (e.g., horizontal direction) along the longitudinal axis 97, thereby enabling the total pressure sensing ports 210 to collect data indicative of the impact pressure of an air flow through the blower 145. Meanwhile, each of the static pressure sensing ports 212 of a particular sensing port 208 may be oriented in different directions (e.g., horizontal directions) that extend at a respective angle (e.g., non-zero angle) relative to the longitudinal axis 97, thereby limiting error associated with directionalized airflow. The sensing ports 208 may be coupled to a pressure transducer 213 (e.g., pressure transducer) via signal tubing 214, and the pressure transducer 213 may be configured to measure the difference in pressure between the total pressure sensing ports 210 and the static pressure sensing ports 212, which may be indicative of an air flow velocity through the blower 145.

[0080] Thus, as an air flow is directed across the probes 206, the air flow may be directed into the sensing ports 208 which are communicatively coupled to the pressure transducer 213 via the signal tubing 214, thereby enabling the pressure transducer 213 to determine a differential pressure between the total pressure sensing ports 210 and the static pressure sensing ports 212. In turn, the pressure transducer 213 may communicate such data (e.g., the differential pressure) to the controller 106, thereby enabling the controller to determine (e.g., calculate) an air flow velocity through the blower 145. In this way, the controller 106 may control aspects of the RTU 100 (e.g., the heating unit 159, blowers 145 of the blower assembly 144), as discussed above. In certain embodiments, each of the probes 206 may also be communicatively coupled to one another, thereby enabling an average air flow velocity based on all of the sensor measurements to be calculated. Further, it should be appreciated that while each of the probes 206 is illustrated as having pressure ports 208 with total pressure ports 210 and static pressure ports 212, in other embodiments, one of the probes 206 may include static pressure ports 212 while another probe 206 includes the total pressure ports 210.

[0081] FIG. 11 is a schematic view of an embodiment of the air flow monitoring system 302 including the anemometer sensor assembly 304. Similar to the air flow monitoring system 202 described above, components of the air flow monitoring system 302 (e.g., components of the anemometer sensor assembly 304) may be disposed within the inlet cone 184 (e.g., within the passage 198 defined by the inlet cone 184) of the blower 145. More particularly, components of the anemometer sensor assembly 304 may be coupled to the inlet cone 184 proximate the second end 194 (e.g., throat) of the inlet cone 184 and may extend in a direction (e.g., radially inward direction relative to a central axis of the inlet cone 184) into the passage 198 to collect data indicative of an air flow velocity of an air flow through the blower 145. For example, the anemometer sensor assembly 304 may include one or more anemometers 306 extending (e.g., extending in a radially inward direction) into the passage 198 and configured to detect data indicative of an air flow velocity through the blower 145. In certain embodiments, one or more of the anemometers 306 may correspond to cup anemometers 310 that include a shaft 312 that extends in a first direction into the passage 198 (e.g., direction that extends crosswise relative to the longitudinal axis 97) and one or more arms 314 coupled to the shaft 312. Each of the one or more arms 314 may be oriented radially relative to the shaft 312 (e.g., each arm 314 may extend in a direction that is orthogonal relative to the direction along which the shaft 312 extends) and each arm 314 may include a cup 316 disposed on a distal end of the arm 314. Thus, as an air flow is directed past a respective cup (e.g., in the direction 160 along the longitudinal axis 97), the air flow may impinge upon the cup, thereby causing the respective radially oriented arm to move (e.g., in a direction along the direction 162 of the air flow). As the radially oriented arm 314 moves, the shaft 312 coupled thereto may rotate (e.g., in a direction 318), and the rate of rotation of the shaft 312 may be representative of an air flow velocity of an air flow directed through the blower 145 (e.g., and across the heating unit 159).

[0082] Additionally or alternatively, one or more of the anemometers 306 may correspond to vane anemometers 320 having a propeller or fan 322 that is coupled to a shaft 324 with an axis of rotation that is generally aligned in a common direction with the air flow (e.g., aligned with the direction 160, extends in a direction along the longitudinal axis 97). For example, the propeller or fan 322 may include one or more vanes 326 that extend from the shaft 324 in a direction (e.g., radial direction) relative to the axis of rotation of the shaft 324. The one or more vanes 326 may also be angled relative to a direction of an air flow through the blower (e.g., direction 160), such that as an air flow is directed across the blades 326 of the propeller or fan 322, the shaft 324 of the propeller or fan 322 may begin to rotate along the axis of rotation. The rate of rotation may be representative of the air flow velocity of the air flow directed through the blower 145. Upon detecting data indicative of the air flow velocity through the blower 145, the anemometer sensor assembly 304 may communicate such data to the controller 106, thereby enabling the controller 106 to control aspects of the RTU 100, as discussed above.

[0083] FIG. 12 is a front view of an embodiment of the air flow monitoring system 402 including the flow nozzle and piezometer ring sensor assembly 404, and FIG. 13 is a perspective view of an embodiment of the air flow monitoring system 402 including the flow nozzle and piezometer ring sensor assembly 404. In the illustrated embodiments, components of the flow nozzle and piezometer ring sensor assembly 404 are disposed within and / or are in fluid communication with the passage 198 defined by the inlet cone 184 of the blower 145. For example, the flow nozzle and piezometer ring sensor assembly 404 may include a piezometer ring 406 circumscribing the second end 194 of the inlet cone 184. That is, the piezometer ring 406 may be positioned about an exterior surface 185 of the inlet cone 184 and may be in fluid communication with the passage 198 of the inlet cone 184 via one or more ports 408, thereby enabling the piezometer ring 406 to collect data indicative of an air flow pressure through the inlet cone 184.

[0084] The flow nozzle and piezometer ring sensor assembly 404 may also include an inlet tap 410 (e.g., static pressure tap) positioned proximate the first end 192 of the inlet cone 184. For example, a port 412 may be drilled through the body 196 of the inlet cone 184 proximate the first end 192. The port 412 may extend in a direction (e.g., horizontal direction) along the longitudinal axis 97, and may be configured to receive the inlet tap 410, thereby enabling the inlet tap 410 to collect data indicative of an air flow pressure through the inlet cone 184.

[0085] Each of the piezometer ring 406 and the inlet tap 410 may be coupled to a differential pressure transducer 414, thereby enabling the flow nozzle and piezometer ring sensor assembly 404 to calculate the static pressure drop through the inlet cone 184. For example, the inlet cone 184 may be used as a flow nozzle, and the air flow velocity can be calculated by measuring the static pressure drop through the inlet cone 184. The pressure drop is measured from the inlet tap 410 located proximate the first 192 of the inlet cone 184 to the piezometer ring 406 located proximate the second end 194 of the inlet cone 184. The inlet tap 410 is coupled to the high pressure side of the transducer 414 and the piezometer ring 406 is coupled to the low-pressure side of the transducer 414. The measured pressure drop between the inlet tap 410 and the piezometer ring 406 may be representative of an air flow velocity of an air flow directed through the blowers 145, thereby enabling the controller 106 to control aspects of the RTU 100, as discussed above.

[0086] As set forth above, the present disclosure may provide one or more technical effects useful in operating HVAC systems employing low GWP refrigerants, such as A2L or A3 refrigerants. Embodiments of the present disclosure may include an air flow monitoring system having a controller configured to control aspects of the HVAC system based on data detected by one or more sensors of the air flow monitoring system. More particularly, embodiments of the present disclosure may include a sensor assembly configured to detect data indicative of an air flow velocity of an air flow directed across a heating unit, and communicate such data to a controller, thereby enabling the controller to control aspects of the HVAC system. For example, upon receiving data indicative of an air flow velocity of an air flow falling below a threshold velocity, the controller may perform one or more actions to limit, block, and / or reduce combustion of a low GWP refrigerant employed by the HVAC system. Such actions may include shutting down certain components of the HVAC system (e.g., the heating unit), modifying a setting of certain components (e.g., increasing a speed of a fan employed by the HVAC system), and / or sending an alert indicating that the air flow velocity is approaching and / or below the threshold velocity. In this way, combustion of low GWP refrigerants employed by the HVAC system may be blocked and / or reduced while ensuring compliance with various safety standards imposed on HVAC system employing low GWP refrigerants.

[0087] 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.

[0088] 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).

Claims

1. An air flow monitoring system for a heating, ventilation, and air conditioning (HVAC) system, comprising:one or more sensors configured to detect data indicative of a velocity of an air flow directed through a blower of the HVAC system; anda controller configured to regulate operation of a heating unit of the HVAC system based on the data indicative of the velocity of the air flow directed through the blower.

2. The air flow monitoring system of claim 1, wherein the one or more sensors comprise a pitot tube sensor assembly disposed within an inlet cone of the blower.

3. The air flow monitoring system of claim 2, wherein the pitot tube sensor assembly comprises:a probe extending across a passage defined by the inlet cone, wherein the probe defines a sensing port, and the sensing port defines a total pressure sensing port and a static pressure sensing port; anda pressure transducer fluidly coupled to the total pressure sensing port and the static pressure sensing port and communicatively coupled to the controller, wherein the pressure transducer is configured to measure a pressure difference between the total pressure sensing port and the static pressure sensing port, and wherein the pressure difference is indicative of the velocity of the air flow directed through the blower.

4. The air flow monitoring system of claim 3, wherein the total pressure sensing port of the sensing port is oriented in a direction that extends along a longitudinal axis of a housing of the HVAC system.

5. The air flow monitoring system of claim 4, wherein the static pressure sensing port of the sensing port is offset from the total pressure sensing port and extends at a non-zero angle relative to the longitudinal axis.

6. The air flow monitoring system of claim 1, wherein the one or more sensors comprise an anemometer sensor assembly disposed within an inlet cone of the blower.

7. The air flow monitoring system of claim 6, wherein the anemometer sensor assembly comprises one or more anemometers extending into a passage defined by the inlet cone of the blower, wherein the one or more anemometers comprises one or more components configured to rotate via the air flow directed through the blower, wherein a rate of rotation of the one or more components is indicative of the velocity of the air flow directed through the blower.

8. The air flow monitoring system of claim 1, wherein the one or more sensors comprise a flow nozzle and piezometer ring sensor assembly coupled to an inlet cone of the blower.

9. The air flow monitoring system of claim 8, wherein the inlet cone comprises an upstream end and a downstream end, and wherein the flow nozzle and piezometer ring sensor assembly comprises:a piezometer ring positioned about an exterior surface of the downstream end of the inlet cone and in fluid communication with a passage defined by the inlet cone via one or more first ports;an inlet tap positioned within a second port extending through the upstream end of the inlet cone; anda pressure transducer fluidly coupled to the inlet tap and the piezometer ring and communicatively coupled to the controller, wherein the pressure transducer is configured to measure a pressure drop between the upstream end and the downstream end, and wherein the pressure drop is indicative of the velocity of the air flow directed through the blower.

10. The air flow monitoring system of claim 1, wherein the controller is configured to suspend operation of the heating unit of the HVAC system based on the data indicating that the velocity of the air flow directed through the blower is below a threshold velocity.

11. A heating, ventilation, and air conditioning (HVAC) system, comprising:a housing configured to receive an air flow;a blower assembly positioned within the housing and comprising one or more blowers, wherein the one or more blowers are configured to bias the air flow through the housing;a heating unit positioned within the housing and configured to transfer heat to the air flow directed through the housing; andan air flow monitoring system, comprising:one or more sensor assemblies positioned within the housing and configured to detect data indicative of a flow rate of the air flow biased through the housing via the one or more blowers; anda controller configured to control operation of the heating unit based on the data.

12. The HVAC system of claim 11, wherein the controller is configured to adjust the heating unit to reduce an amount of heat output by the heating unit based on the flow rate of the air flow being below a threshold flow rate.

13. The HVAC system of claim 12, wherein the controller is configured to:adjust the heating unit to reduce the amount of heat output by the heating unit by a first amount in response to a determination that the flow rate of the air flow is below the threshold flow rate; andadjust the heating unit to reduce the amount of heat output by the heating unit by a second amount in response to an additional determination that the flow rate of the air flow is below an additional threshold flow rate,wherein the first amount is less than the second amount and the threshold flow rate is greater than the additional threshold flow rate.

14. The HVAC system of claim 13, wherein the controller is configured to suspend operation of the heating unit in response to a determination that the flow rate of the air flow is below a lower limit threshold flow rate, wherein the lower limit threshold flow rate is less than the additional threshold flow rate.

15. The HVAC system of claim 12, wherein the controller is configured to increase a speed of the one or more blowers to increase the flow rate of the air flow based the flow rate of the air flow being within a threshold range of a threshold flow rate.

16. The HVAC system of claim 11, wherein the one or more sensor assemblies comprises a pitot tube sensor assembly, a flow nozzle and piezometer ring sensor assembly, an anemometer sensor assembly, or any combination thereof.

17. A rooftop unit for a heating, ventilation, and air conditioning (HVAC) system, comprising:a housing comprising a blower chamber;one or more blowers disposed within the blower chamber and configured to direct an air flow through the housing;a heating unit positioned within the housing downstream of the blower chamber, relative to a flow direction of the air flow through the housing, wherein the heating unit is configured to heat the air flow during a heating mode of the HVAC system;one or more sensors coupled to the one or more blowers, wherein the one or more sensors are configured to detect data indicative of a velocity of the air flow; anda controller configured to:compare the velocity to one or more threshold values; andadjust an amount of heat output by the heating unit based on a comparison of the velocity to the one or more threshold values.

18. The rooftop unit of claim 17, wherein the controller is configured to:decrease the amount of heat output by the heating unit by a first amount based on the velocity being below a first threshold value of the one or more threshold values; anddecrease the amount of heat output by the heating unit by a second amount based on the velocity being below a second threshold value of the one or more threshold values,wherein the first amount is less than the second amount, and the second threshold value is less than the first threshold value.

19. The rooftop unit of claim 17, wherein the one or more blowers is configured to bias the air flow through the housing in a first direction, the housing is configured to discharge the air flow from the housing in a second direction, and the second direction extends crosswise relative to the first direction.

20. The rooftop unit of claim 17, wherein the one or more sensors comprises a pitot tube sensor assembly, a flow nozzle and piezometer ring sensor assembly, an anemometer sensor assembly, or any combination thereof.

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