Patent Publication Number: US-2020292182-A1

Title: Feedback warning system using inducer pulse width modulation signal

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application Ser. No. 62/817,857, entitled “FEEDBACK WARNING SYSTEM USING INDUCER PULSE WIDTH MODULATION SIGNAL” and filed on Mar. 13, 2019, which is expressly incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     The present disclosure relates generally to heating, ventilation, and air conditioning (HVAC) systems, and more particularly, to a warning system for HVAC systems using an inducer pulse width modulation (PWM) signal. 
     In some HVAC system, including low nitrogen oxides (NOx) systems, efficient combustion airflow may be necessary to remove exhaust gases from a combustion chamber. However, in some instances, the combustion airflow may be blocked due to, for example, particles in a mesh or filter or one or more objects blocking an airflow of a flue. A blocked combustion airflow may prevent the HVAC system from initiating furnace operation or efficiently operating and, in some cases, may damage one or more components of the HVAC system. In typical HVAC systems, detection and warning systems for blocked combustion airflow may be costly, may add unnecessary complexity to the HVAC system, and may require a significant amount of space within the HVAC system. Accordingly, improvements are desired in HVAC systems. 
     SUMMARY 
     The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later. 
     The present disclosure provides systems, apparatuses, and methods for generating a status notification of a combustion airflow by a heating, ventilation, and air conditioning (HVAC) system. 
     In an aspect, an HVAC system may include an inducer motor configured to provide combustion airflow in the HVAC system, a pressure sensor configured to measure an output airflow pressure of the inducer motor, a memory configured to store a set of instructions, and a processor coupled with the memory and configured to execute the set of instructions. The processor may be configured to initiate an inducer motor within the HVAC system. The processor may also be configured to send a pulse width modulation (PWM) signal to the inducer motor, wherein the PWM signal corresponds to a predetermined airflow pressure of the inducer motor and measured by the pressure sensor. The processor may further be configured to compare the PWM signal to a baseline value. The processor may also be configured to control the inducer motor based on the comparing of the PWM signal to the baseline value. The processor may further be configured to generate a status notification of the combustion airflow of the HVAC system in response to the comparing the PWM signal to the baseline value. 
     In another aspect, a method for generating a status notification of a combustion airflow by an HVAC system is disclosed. The method may include initiating an inducer motor within the HVAC system, the inducer motor configured to provide the combustion airflow in the HVAC system. The method may also include receiving an output airflow pressure of the inducer motor from a pressure sensor. The method may include sending a PWM signal to the inducer motor, wherein the PWM signal corresponds to a predetermined airflow pressure of the inducer motor and received from the pressure sensor. The method may further include comparing the PWM signal to a baseline value. The method may include controlling the inducer motor based on the comparing of the PWM signal to the baseline value. The method may also include generating a status notification of the combustion airflow of the HVAC system in response to the comparing the PWM signal to the baseline value. 
     In another aspect, a computer-readable medium storing computer executable code for generating a status notification of a combustion airflow by an HVAC system is disclosed. The computer-readable medium may include code to initiate an inducer motor within the HVAC system, the inducer motor is configured to provide the combustion airflow in the HVAC system. The computer-readable medium may also include code to receive an output airflow pressure of the inducer motor. The computer-readable medium may include code to send a PWM signal to the inducer motor, wherein the PWM signal corresponds to a predetermined airflow pressure of the inducer motor and received from the pressure sensor. The computer-readable medium may further include code to compare the PWM signal to a baseline value. The computer-readable medium may include code to control the inducer motor based on the comparing of the PWM signal to the baseline value. The computer-readable medium may also include code to generate a status notification of the combustion airflow of the HVAC system in response to the comparing the PWM signal to the baseline value. 
     To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosed aspects will hereinafter be described in conjunction with the appended drawings, provided to illustrate and not to limit the disclosed aspects, wherein like designations denote like elements, and in which: 
         FIG. 1  is a block diagram of an example heating, ventilation, and air conditioning (HVAC) system, according to aspects of the present disclosure; 
         FIG. 2  is a block diagram of an example of functions of a furnace, according to aspects of the present disclosure; 
         FIG. 3  is a flowchart of an example method, according to aspects of the present disclosure; and 
         FIG. 4  is a block diagram of an example of components of the HVAC unit of  FIG. 1 , according to aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known components may be shown in block diagram form in order to avoid obscuring such concepts. 
     Aspects of the present disclosure provide systems, methods, and computer-readable medium for generating a status notification of a combustion airflow by a heating, ventilation, and air conditioning (HVAC) system. In an HVAC system, an inducer motor removes any gas remaining from a previous combustion cycle from a furnace via a flue. In some cases, efficient combustion airflow or furnace ignition may be prevented due to, for example, a filter or a mesh of a premix burner accumulating particles, or the flue being blocked by one or more objects. A typical warning system, which may include airflow sensors, power analyzers, or filter exchange timers are either costly, consume a significant amount of space within the HVAC system, or do not provide sufficient warning of the combustion airflow being blocked. 
     The present disclosure uses a pulse width modulation (PWM) signal to control inducer motor work performance. Unlike analyzing power measured in watts directly, the PWM signal allows a comparative measurement. In an aspect, a controller may initiate an initial run of the inducer motor. When the inducer motor reaches a predetermined airflow pressure, the controller may record an initial PWM signal (baseline value or field set baseline value) corresponding to the predetermined airflow pressure. The initial PWM signal may be recorded, for example, when the HVAC system is initially setup at a location (e.g., a first time run of the inducer motor in the HVAC system). The initial PWM signal may be a baseline value used for comparing whether the inducer motor requires a different PWM value to reach the predetermined airflow pressure. Each baseline value may be specific to setup (e.g., mountainous install, varying vent and/or air intake pipe lengths) of the HVAC system. The controller may use the baseline value to compare at set point operation how much a subsequent PWM signal deviates from the baseline value. The controller may issue a warning alert and/or a critical alert based on a deviation. For example, an alert (e.g., warning or critical) may be issued if a deviation percentage exceeds a threshold percentage from the baseline value. 
     Use of the PWM signal, as described in the present disclosure, may provide a low cost, warning system for an HVAC system, as compared to a conventional warning system. Use of the warning system of the present disclosure may provide an up-to-date notification of a blockage in the combustion airflow as a result of heat exchanger soot preventing oxygen in combustion air, excess pollutants and emissions due to combustion mixture changes from the lack of fresh air flow, or any other blockage in the combustion airflow. 
     Turning now to the figures, example aspects are depicted with reference to one or more components described herein, where components in dashed lines may be optional. 
     Referring to  FIG. 1 , an HVAC system  100  for a building  10  is disclosed. The HVAC system  100  may include an HVAC unit  110  configured to control an ambient condition of the one or more areas (e.g., rooms) of the building  10  based on information from one or more sensors  150  and a mobile device  160 . In an example, an ambient condition may be a temperature or a humidity level of one or more areas of the building  10 . As shown by  FIG. 1 , the HVAC unit  110  may be external to the building  10 . Alternatively, in some aspects, one or more components (e.g., air conditioning (A/C) unit  112 , furnace  114 , blower  116 , humidifier/dehumidifier  118 , communications component  130 , or controller  140 ) may be located in different locations including inside the building  10 . Examples of the building  10  may include a home, an office, or any other structure that may use an HVAC system for controlling one or more ambient conditions of the structure. 
     In an aspect, the HVAC system  100  may include supply ducts  120  and return ducts  124  installed within the building  10  and coupled with the HVAC unit  110 . The supply ducts  120  may supply air to the building  10 , and the return ducts  124  may return air from the building  10 . The supply ducts  120  may receive supply air through one or more of intakes  128  that provide outside air to the HVAC system  100  and/or may recycle return air from the return ducts  124 . The supply ducts  120  may output the supply air at one or more of the areas of the building  10  via one or more supply vents  122 . The return ducts  124  may receive return air from the building  10  via the return ducts  124  to balance air within the building  10 . The return air may be input into the return ducts  124  via one or more return vents  126 . 
     The HVAC unit  110  may include one or more of an A/C unit  112 , a furnace  114 , a blower  116 , a humidifier/dehumidifier  118 , or any other component for adjusting an ambient condition of an area (e.g., room) of the building  10 . The A/C unit  112  may be configured to cool the supply air by passing the supply air through or around one or more cooled pipes (e.g., chiller pipes) to lower a temperature of the supply air. The furnace  114  may be configured to warm the supply air by passing the supply air through or around one or more warmed pipes (e.g., heating coils) to raise a temperature of the supply air. The blower  116  may be configured to blow the supply air through the supply ducts  120  to the building  10  and pull the return air from the building  10 . The humidifier  118  may be configured to add moisture to the supply air, and the dehumidifier  118  may be configured to reduce moisture in the supply air. While the humidifier/dehumidifier  118  is shown as a single unit, these units may be separate units. Alternatively to a dehumidifier  118 , aspects of dehumidification may be performed through other methods including use of the A/C unit  112  to dehumidify the supply air. 
     The HVAC unit  110  may also include a communications component  130  configured to communicate with the one or more sensors  150  and/or the mobile device  160 . In an aspect, the communications component  130  may communicate with the one or more sensors  150  and/or the mobile device  160  via one or more communications links  132 . In an example, the communications component  130  may include one or more antennas, processors, modems, radio frequency components, and/or circuitry for communicating with the sensors  150  and/or the mobile device  160 . The one or more communications links  132  may be one or more of a wired communication link or a wireless communication link. 
     The HVAC system  100  may also include the one or more sensors  150  located within one or more areas of the building  10  and/or within or near the supply vents  122 . One or more sensors  150  may be configured to detect an ambient condition such as a temperature or a humidity level of the area where the sensor  150  is located. Each of the sensors  150  may provide sensor information  180  to the HVAC unit  110 . Examples of a sensor  150  may include a temperature sensor, a humidity sensor, or any sensor configured to detect an ambient condition of one or more areas of the building  10 . 
     The HVAC system  100  may also include the mobile device  160  configured to communicate with the HVAC unit  110 . The mobile device may include an HVAC application  162  configured to display, adjust, and store setpoint information (“info”)  164  indicating desired user settings for one or more areas of the building  10 . In an example, the setpoint information  164  may include heating/cooling settings  166  indicating one or more desired temperatures (e.g., minimum and/or maximum area temperatures) for one or more areas of the building and/or humidity settings  168  indicating a desired humidity level for one or more areas of the building  10 . The mobile device  160  may provide the setpoint information  164  to the HVAC unit  110 . Examples of a mobile device  160  may include a cellular phone, a smart phone, a personal digital assistant (PDA), a smart speaker, a home assistant, a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a smart watch, an entertainment device, an Internet of Things (IoT) device, or any device capable of communicating with the HVAC unit  100 . A smart speaker may include, for example, an Echo® device available from Amazon, Inc. of Seattle, Wash., a Google Home® device available from Google, Inc. of Mountain View, Calif., or other similar voice-controlled devices. The HVAC application  162  may include a voice interface that responds to voice commands. 
     The HVAC unit  110  may also include a controller  140  configured to control the A/C unit  112 , the furnace  114 , the blower  116 , and the humidifier/dehumidifier  118 , based on the sensor information  180  received from the sensor  150  and the setpoint information  164  received from the mobile device  160 . While the controller  140  is shown in  FIG. 1  as being located external to the building (e.g., within HVAC unit  110 ), aspects of the present disclosure do not limit the controller  140  to this location. For example, the controller  140  may be located within an area of the building  10  and/or combined with one or more sensors  150 . 
     The controller  140  may communicate with the communications component  130 , the A/C unit  112 , the furnace  114 , the blower  116 , and/or the humidifier/dehumidifier  118  via a communications bus  134 . The controller  140  may include logic to operate the A/C unit  112 , the furnace  114 , the blower  116 , and the humidifier/dehumidifier  118 , based on the sensor information  180  and the setpoint information  164 . The operation of the components of the HVAC unit  110  may include one or more of an initiation time, a stop time, a run time, a power state, speed level, a heating/cooling level, and/or any other operational state of one or more of these components of the HVAC unit  110 . 
     In an aspect, the controller  140  may include an operation control component  142  to perform the logic of the controller  140 . The operation control component  142  may include a monitoring component  170  configured to monitor and compare the setpoint information  164  and the sensor information  180 . In an example, the monitoring component  170  may include an information receiver  170  configured to receive one or more of the setpoint information  164  or the sensor information  180 . The monitoring component  170  may also include a comparer  174  configured to receive one or more of the setpoint information  164  or the sensor information  180  from the information receiver  172  and determine a difference between the setpoint information  164  (or stored setpoint information) and the sensor information  180 . 
     In an aspect, the operation control component  142  may also include a system operator  176  configured to determine one or more operational states for controlling one or more functions of the components (e.g., A/C unit  112 , furnace  114 , blower  116 , humidifier/dehumidifier  118 ) of the HVAC unit  110  and control the components based on the determined operations. For example, the system operator  176  may determine one or more of an initiation time, a stop time, a run time, a power state, speed level, or a heating/cooling level, of one or more of the components and control the components according to the operational state(s). 
     In an example, the system operator  176  may receive information on the difference between the setpoint information  164  (or stored setpoint information) and the sensor information  180  from the comparer  174  and determine an operational state of the components. The system operator  176  may compare the difference between the setpoint information  164  (or stored setpoint information) and the sensor information  180  and determine whether the difference is within a threshold range. The system operator  176  may determine operational states based on a result of the determination. 
     While the controller  140 , the communications component  130 , the sensors  150 , and the mobile device  160  are shown separately in  FIG. 1 , aspects of the present disclosure do not limit the functionality of these components being separated. For example, one or more of the functionalities of the controller  140 , the communications component  130 , the sensors  150 , or the mobile device  160  may be combined (e.g., thermostat) so that a user may access the functionalities within the building  10 . 
     Referring to  FIG. 2 , an example of a heating cycle of the furnace  114 , according to aspects of the present disclosure, is provided. As shown, the furnace  114  may include a burner  202  configured to release and burn a gas (e.g., natural gas or propane) within a heat exchanger  204 . The heat exchanger  204  may be a set of pipes and, in some examples, fins, configured to transfer heat from the pipes to air that passes over (externally) the heat exchanger  204 . 
     During a heating cycle, the blower  118  may pass air along a supply airflow  250  such that the air passes over the heat exchanger  204  to heat the air. The air, after having passed over the heat exchanger  204 , is pushed to the building  10  via the supply duct  120 , as described herein. 
     The furnace  114  may also include an inducer motor (e.g., blower)  206  configured to pull air/gas from the burner  202  and the heat exchanger  204  and vent the air/gas out of a flue  208 . The combustion airflow  260  may be the path air/gas follows from the burner  202  through the heat exchanger  204 , the inducer motor  206 , and the flue  208 . The inducer motor  206  may be powered by a voltage (e.g., 110 VAC) and a controlled via a PWM signal. In some examples, the inducer motor  206  may initiate prior to an initiation of the burner  202  in order to clear the air/gas in the combustion airflow  260  that may have remained from a prior heating cycle. Clearing the air/gas from the combustion airflow  260  prior to the initiation of the burner  202 , provides a controlled burn for the burner  202  (e.g., prevents uncontrolled explosions in heat exchanger  204  from left over gas). Further, the inducer motor  206  may remain running while the burner  202  is burning to provide a source of oxygen to the burner  202  and allow the burner  202  to burn efficiently. 
     The furnace  114  may also include a pressure sensor  210  configured to measure an output airflow pressure of the inducer motor  206 . The pressure signal  210  may be located at or near the output of the inducer motor or any location to measure an output/input airflow force of the inducer motor (e.g., anywhere within the flue  208 ). 
     In some situations, a combustion airflow may be blocked. Blockage may occur do to any number of reasons, for example, soot or particles caught in a mesh or filter of a premix burner, one or more objects covering the flue, and/or a general build-up of soot or particles along the combustion airflow corresponding to one or more of the burner  202 , the heat exchanger  204 , the inducer motor  206 , or the flue  208 . 
     In an aspect, the controller  140  may monitor the inducer motor  206  and generate a status notification based on a PWM signal. A change in the PWM signal to the inducer motor  206  from a baseline value may indicate that the combustion airflow is blocked. For example, when the combustion airflow is blocked (either partially or wholly), the inducer motor  206  may become strained and require the PWM to run at a higher duty cycle in order to reach a desired airflow pressure. Accordingly, the monitoring component  170  may be configured to monitor the PWM (PWM signal) via, for example, a communication bus  212  and also monitor an output airflow pressure via the pressure sensor  210 . When the output airflow pressure reaches a predetermined airflow pressure, the monitoring component  170  may verify the PWM signal to the inducer motor  206  at the predetermined airflow pressure. The comparer  174  may then compare the PWM signal to a baseline value. The baseline value may indicate a baseline PWM signal corresponding to a desired airflow pressure of the inducer motor  206 . In an aspect, one or more of the baseline PWM signal or the predetermined airflow pressure may be based on a manufacture, installer, or user setting. In another aspect, one or more of one or more of the baseline PWM signal or the predetermined airflow pressure may be based on an initial setup of one or more components of the HVAC system  100 . For example, when the inducer motor  206 , the furnace  114 , and/or the HVAC unit  110  is initially setup, the controller  140  (or one or more subcomponents) may initiate the inducer motor  206 . The controller  140  (or one or more subcomponents) may monitor the airflow pressure of the inducer motor  206  via the pressure sensor  210 . When the output airflow pressure of the inducer motor  206  reaches a predetermined airflow pressure, the controller  140  (or one or more subcomponents) may record the PWM signal corresponding to the predetermined airflow pressure. The recorded PWM signal may be the baseline value. Alternatively, the controller  140  (or one or more subcomponents) may determine a baseline range (e.g., +/−10% deviation) from the recorded PWM signal, and the baseline range may be used by the controller  140  as the baseline value. 
     During a heating cycle of the furnace  114 , the monitoring component  170  may monitor the PWM to the inducer motor  206  and monitor the output airflow pressure via the pressure sensor  210 . When the output airflow pressure reaches the predetermined airflow pressure, the PWM signal, which indicates a PWM signal of the inducer motor corresponding to the predetermined airflow pressure is verified, and the comparer  174  may compare the PWM signal to the baseline value. 
     Based on the comparison, the system operator  176  may control the inducer motor  206 . For example, if the PWM signal matches the baseline value, the inducer motor  206  may be operating at a normal state. However, if the PWM signal exceeds the baseline value or another threshold, the inducer motor  206  may be operating at a warning state. 
     Further, a notification component  178  of the operation control component  142  may generate a status notification based on the comparison. For example, the notification component  178  may generate a status notification of a normal status to indicate the combustion airflow is not blocked, a warning status to indicate the combustion airflow is at least partially blocked, or a critical status to indicate the combustion airflow is largely blocked. 
     In some examples, the notification component  178  may determine a deviation of the PWM signal from the baseline value, and generate the status notification of the combustion airflow further based on the deviation. The notification component  178  may further compare the deviation to a first threshold and/or a second threshold to determine whether a deviation percentage exceeds a threshold percentage from the baseline value. When the deviation is satisfies the first threshold, the notification component  178  may generate the normal status. When the deviation exceeds the first threshold but does not exceed the second threshold, the notification component  178  may generate the warning status. When the deviation exceeds the second threshold, the notification component  178  may generate the critical status. 
     Referring to  FIG. 3 , an example of a method  300  for generating a status notification of a combustion airflow by the HVAC system  100  is disclosed. The method  300  may implement the functionality described herein with reference to  FIGS. 1 and 2  and may be performed by one or more components of the HVAC system  100  as described herein with reference to  FIGS. 1, 2, and 4 . 
     At  302 , the method  300  may include initiating an inducer motor within the HVAC system. For example, one or more components (e.g., processor  410 , memory  420 , operation control component  142 , or system operator  176 ) of the HVAC unit  110  may initiate the inducer motor  206  within the furnace  114 . 
     At  304 , the method  300  may include receiving an output airflow pressure of the inducer motor from a pressure sensor. For example, one or more components (e.g., processor  410 , memory  420 , operation control component  142 , monitoring component  170 , and/or information receiver  172 ) may receive an output airflow pressure of the inducer motor  206  via the pressure sensor  210 . 
     At  306 , the method  300  may also include sending a PWM signal to the inducer motor. For example, one or more components (e.g., processor  410 , memory  420 , operation control component  142 , and/or system operator  176 ) of the HVAC unit  110  may send a PWM signal to the inducer motor  206 . In an example, the PWM signal may correspond to a predetermined airflow pressure of the inducer motor  206  and received from the pressure sensor  210 . In an example, the PWM signal may indicate a speed of the inducer motor  206 . 
     At  308 , the method  300  may include comparing the PWM signal to a baseline value. For example, one or more components (e.g., processor  310 , memory  320 , operation control component  142 , monitoring component  170 , and/or comparer  174 ) of the HVAC unit  110  may compare the PWM signal to a baseline value. In an example, the baseline value may indicate a baseline range of a PWM signal for the inducer motor  206 . In some examples, the baseline value may correspond to an initial PWM signal recorded at an initial setup of the inducer motor  206 , the furnace  114 , and/or the HVAC unit  110 . 
     At  310 , the method  300  may also include controlling the inducer motor based on the comparing of the PWM signal to the baseline value. For example, one or more components (e.g., processor  310 , memory  320 , operation control component  142 , and/or system operator  176 ) of the HVAC unit  110  may control the inducer motor  206  based on the comparing of the PWM-signal to the baseline value. 
     At  312 , the method  300  may further include generating a status notification of the combustion airflow of the HVAC system in response to the comparing the PWM signal to the baseline value. For example, one or more components (e.g., processor  310 , memory  320 , operation control component  142 , and/or notification component  178 ) of the HVAC unit  110  may generate a status notification of the combustion airflow  260  of the HVAC system  100  in response to the comparing the PWM signal to the baseline value. 
     In an aspect, the method  300  may include determining a deviation of the PWM signal from the baseline value. The controlling of the inducer motor and the generating of the status notification of the combustion airflow are further based on the deviation. 
     In some examples, when the deviation satisfies a first threshold, the controlling of the inducer motor may include operating the inducer motor in a normal state, and the status notification of the combustion airflow may be a normal status to indicate the combustion airflow is not blocked. 
     In some examples, when the deviation exceeds a first threshold, the controlling of the inducer motor may include operating the inducer motor in a warning state, and the status notification of the combustion airflow may be a warning status to indicate the combustion airflow is at least partially blocked. 
     In some examples, when the deviation exceeds a second threshold, the controlling of the inducer motor includes operating the inducer motor in a critical state (e.g., stopping the inducer motor  206 ), and the status notification of a combustion airflow may be a critical status to indicate the combustion airflow is largely blocked. 
     In some aspects, the method  300  may include transmitting the status notification of the combustion airflow to one or more of a display, a thermostat, or a mobile device. For example, a status notification may be displayed by the user interface  400  of the controller  140  via a status indicator  450 , and/or transmitted to the mobile device  160  via email, text message, or any other method of notification. 
     Referring to  FIG. 4 , the HVAC unit  110  and the controller  140  may include a variety of components, some of which have already been described herein. As shown, the controller  140  may also include a user interface  400 , a processor  410 , and a memory  420  which operate in conjunction to perform one or more functions described herein related to the faceless system control. The user interface  400  may operate to receive information from the processor  410  and communicate the information to a user. In an example, the user interface  400  may include one or more lights, speakers, or displays to communicate the information to the user. In an example, the user interface  400  may include a status indicator  450  to indicate one or more status notifications from the notification component  178  such as a normal status, a warning status, or a critical status of the combustion airflow  260 . The processor  410  may be one or more processors configured to control the HVAC unit  110  and perform one or more functions described herein. 
     The memory  420  may be configured to store data (e.g., setpoint information  420 , operational settings  422 ) used herein and/or functions and operations performed by the processor  410  and/or the operation control component  142 . The memory  420  may include any type of computer-readable medium usable by a computer or at least one processor  420 , such as random access memory (RAM), read only memory (ROM), tapes, magnetic discs, optical discs, volatile memory, non-volatile memory, and any combination thereof. In an aspect, the memory  420  may be a non-transitory computer-readable storage medium that stores one or more computer-executable codes defining the operation control component  142  and/or one or more of subcomponents of the operation control component  142 , and/or data associated therewith, when HVAC unit  110  is operating the processor  410  to execute the operation control component  142  and/or one or more of subcomponents. 
     The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C,” “one or more of A, B, or C,” “at least one of A, B, and C,” “one or more of A, B, and C,” and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C,” “one or more of A, B, or C,” “at least one of A, B, and C,” “one or more of A, B, and C,” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module,” “mechanism,” “element,” “device,” and the like may not be a substitute for the word “means.” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for.”