Abstract: A method is provided for controlling an HVAC system. The method includes receiving zone priority levels and zone temperature setpoints, where at least one of the zones haves a higher priority level than others of the zones, receiving an indication of zone ambient temperature values, determining requested zone capacity values to maintain the zone ambient temperature values within a threshold deviation of respective ones of the zone temperature setpoints, determining target zone capacity values from the requested zone capacity values and zone size values, and from the zone priority levels where the target zone capacity values may be responsive to a total of the requested zone capacity values that is less than a minimum capacity or greater than a maximum capacity of the HVAC system, and causing the HVAC system to provide the conditioned air to the zones according to respective ones of the target zone capacity values.

Abstract: A method is provided for controlling an HVAC system. The method includes receiving zone priority levels and zone temperature setpoints, where at least one of the zones haves a higher priority level than others of the zones, receiving an indication of zone ambient temperature values, determining requested zone capacity values to maintain the zone ambient temperature values within a threshold deviation of respective ones of the zone temperature setpoints, determining target zone capacity values from the requested zone capacity values and zone size values, and from the zone priority levels where the target zone capacity values may be responsive to a total of the requested zone capacity values that is less than a minimum capacity or greater than a maximum capacity of the HVAC system, and causing the HVAC system to provide the conditioned air to the zones according to respective ones of the target zone capacity values.

Abstract: A method is provided for controlling combustion in a modulating gas furnace. The method includes receiving an indication of a firing rate setpoint for a burner assembly, and applying the firing rate setpoint to first and second continuous functions that map the firing rate setpoint to air-to-fuel ratio and combustion system pressure setpoints. A variable-speed draft inducer blower is set to drive to a combustion system pressure setpoint, and the modulating gas valve is controlled during combustion in the combustion system. In this regard, a combustion system pressure measurement is obtained and applied to an inverse of the first continuous function that outputs an adjusted firing rate for the combustion system pressure measurement. The adjusted firing rate is applied to a third continuous function that maps the firing rate to gas valve position, and outputs a gas valve position to which the modulating gas valve is set.

Abstract: Methods and related systems for operating a furnace are disclosed. In an embodiment, the method includes activating a burner assembly and a first fan of the furnace to combust fuel and air and circulate combustion gases along a flow path extending through a heat exchanger of the furnace. In addition, the method includes operating a second fan of the furnace to circulate air across an external surface of the heat exchanger of the furnace and produce a conditioned airflow. Further, the method includes monitoring one or more parameters of a motor of the second fan indicative of an airflow rate of the conditioned airflow, and deactivating the burner assembly, whereby combustion of the fuel and air in the furnace ceases, in response to the one or more parameters indicating that the airflow rate is less than a minimum airflow rate.

Abstract: Methods and related systems for operating a furnace are disclosed. In an embodiment, the method includes activating a burner assembly and a first fan of the furnace to combust fuel and air and circulate combustion gases along a flow path extending through a heat exchanger of the furnace. In addition, the method includes operating a second fan of the furnace to circulate air across an external surface of the heat exchanger of the furnace and produce a conditioned airflow. Further, the method includes monitoring one or more parameters of a motor of the second fan indicative of an airflow rate of the conditioned airflow, and deactivating the burner assembly, whereby combustion of the fuel and air in the furnace ceases, in response to the one or more parameters indicating that the airflow rate is less than a minimum airflow rate.

Abstract: Climate control systems and related methods and systems therefore a disclosed. In an embodiment, the climate control system includes a heat exchanger configured to discharge conditioned air to an indoor space. In addition, the climate control system includes a display and a controller coupled to the display. The controller is to generate an operation selection option on the display. The operation selection option includes a plurality of selections for operating of the climate control system based on operational efficiency or occupant comfort within the indoor space. The controller is to adjust a temperature of the heat exchanger relative to a user selection from the plurality of selections.

Abstract: A method is provided for controlling an HVAC system. The method includes receiving zone airflow target values for zones of a conditioned space. The method includes accessing a duct model including a first term that describes a flow factor for a zone damper as a nonlinear function of damper position, and a second term that describes zone airflow as a function of the flow factor and a branch pressure across zone-specific branches of an air circulation path. The method includes applying the zone airflow target values to the duct model to determine a damper position set, and actuating zone dampers to respective damper positions of the damper position set. The method may also include determining a value of total airflow to achieve the zone airflow target values with a total pressure target, and causing a fan to provide conditioned air with the value of the total airflow.

Abstract: A method is provided for controlling an HVAC system. The method includes receiving zone priority levels and zone temperature setpoints, where at least one of the zones haves a higher priority level than others of the zones, receiving an indication of zone ambient temperature values, determining requested zone capacity values to maintain the zone ambient temperature values within a threshold deviation of respective ones of the zone temperature setpoints, determining target zone capacity values from the requested zone capacity values and zone size values, and from the zone priority levels where the target zone capacity values may be responsive to a total of the requested zone capacity values that is less than a minimum capacity or greater than a maximum capacity of the HVAC system, and causing the HVAC system to provide the conditioned air to the zones according to respective ones of the target zone capacity values.

Abstract: Methods and related systems for operating a climate control system for an indoor space are disclosed. In an embodiment, the method includes operating an indoor fan of the climate control system to rotate an impeller of the indoor fan in a reverse rotational direction opposite a nominal rotational direction of the impeller. Additionally, the method includes determining an airflow of the indoor fan when the impeller of the indoor fan is rotated in the reverse rotational direction. Further, the method includes determining a duct leakage rate associated with at least one duct of the climate control system based on the determined airflow, wherein the at least one duct is sealed-off at an end thereof.

Abstract: Methods and related systems for detecting inaccurate airflow delivery of an indoor unit of a climate control system are disclosed. In an embodiment, the method includes operating a fan of the climate control system by transmitting a requested airflow value from a controller of the climate control system to a controller of the fan. Additionally, the method includes collecting estimated airflow values of the indoor fan, and identifying a steady state condition of the climate control system. Further, the method includes determining airflow error values, and issuing at least one of a first alert to a user of the climate control system in response to at least one of the airflow error values being equal to or greater than an alert value, and a second alert to the user in response to each of the airflow error values being less than the alert value.

Abstract: Methods and related systems for estimating input power supplied to a fan motor of a climate control system are disclosed. In an embodiment, the method includes selecting an input power function of a fan motor class. Additionally, the method includes operating a fan of the climate control system to produce an airflow, wherein the fan includes the fan motor of the selected fan motor class. Further, the method includes measuring a speed and a torque of the fan motor, and estimating an input power of the fan motor by entering the speed and the torque of the fan motor into the selected input power function.

Abstract: Methods and related systems for operating a furnace are disclosed. In an embodiment, the method includes activating a burner assembly and a first fan of the furnace to combust fuel and air and circulate combustion gases along a flow path extending through a heat exchanger of the furnace. In addition, the method includes operating a second fan of the furnace to circulate air across an external surface of the heat exchanger of the furnace and produce a conditioned airflow. Further, the method includes monitoring one or more parameters of a motor of the second fan indicative of an airflow rate of the conditioned airflow, and deactivating the burner assembly, whereby combustion of the fuel and air in the furnace ceases, in response to the one or more parameters indicating that the airflow rate is less than a minimum airflow rate.

Abstract: A method for calibrating a motor is provided. The method includes defining a reference speed for operating the motor; operating the motor until a first operating point at which the motor reaches the reference speed; measuring a first current of the motor and an angular acceleration associated with the first current at the first operating point; operating the motor until a second operating point at which the motor reaches the reference speed; measuring a second current of the motor at the second operating point; and estimating a calibration coefficient for calibrating the motor based at least on the first current, the second current, and the angular acceleration associated with the first current.

Abstract: This disclosure relates to flame shapers for use in gas burners, gas burner systems, and methods for operating gas burner systems. Flame shaper embodiments include an opening having an unobstructed center, and turning vanes that extend from the perimeter of the opening towards its center. The turning vanes are configured to induce swirling in an ignited flame. Burner systems include an ignition source, the flame shaper, and a heat exchanger. In method embodiments, a flame is formed by igniting fuel and air, the flame is directed through the flame shaper, and the flame is then directed into a heat exchanger.

Abstract: A heating, ventilation and air condition (HVAC) system is provided. The system includes a thermostat including an onboard temperature sensor, a remote temperature sensor in operable communication with the thermostat, and a controller in operable communication with each of the onboard sensor and the remote sensor and configured to execute a control algorithm that calculates a temperature difference between a temperature detected by the onboard temperature sensor and a temperature detected by the remote temperature sensor, such that when the remote temperature sensor fails, the controller uses the calculated temperature difference to calibrate the onboard temperature sensor and set the thermostat to the temperature detected by the remote temperature sensor.

Abstract: This disclosure relates to flame shapers for use in gas burners, gas burner systems, and methods for operating gas burner systems. Flame shaper embodiments include an opening having an unobstructed center, and turning vanes that extend from the perimeter of the opening towards its center. The turning vanes are configured to induce swirling in an ignited flame. Burner systems include an ignition source, the flame shaper, and a heat exchanger. In method embodiments, a flame is formed by igniting fuel and air, the flame is directed through the flame shaper, and the flame is then directed into a heat exchanger.

Abstract: A method for calibrating a motor is provided. The method includes defining a reference speed for operating the motor; operating the motor until a first operating point at which the motor reaches the reference speed; measuring a first current of the motor and an angular acceleration associated with the first current at the first operating point; operating the motor until a second operating point at which the motor reaches the reference speed; measuring a second current of the motor at the second operating point; and estimating a calibration coefficient for calibrating the motor based at least on the first current, the second current, and the angular acceleration associated with the first current.

Abstract: A heat exchanger tube includes a first pass for at least partially combusting a fuel and the first pass having a modified shape including a minor diameter and major diameter that reduces the external pressure drop of an external fluid flowing across the heat exchanger tube. A HVACR system includes a heat exchanger tube with a first heat exchange pass that at least partially combusts a fuel and has a modified shape. A method of making a heat exchanger including configuring a first heat exchange pass such that the major diameter of modified portion of the first heat exchange pass is oriented towards an incoming direction of the process fluid.

Abstract: A heating, ventilation and air condition (HVAC) system is provided. The system includes a thermostat including an onboard temperature sensor, a remote temperature sensor in operable communication with the thermostat, and a controller in operable communication with each of the onboard sensor and the remote sensor and configured to execute a control algorithm that calculates a temperature difference between a temperature detected by the onboard temperature sensor and a temperature detected by the remote temperature sensor, such that when the remote temperature sensor fails, the controller uses the calculated temperature difference to calibrate the onboard temperature sensor and set the thermostat to the temperature detected by the remote temperature sensor.

Abstract: A heat exchanger tube includes a first pass for at least partially combusting a fuel and the first pass having a modified shape including a minor diameter and major diameter that reduces the external pressure drop of an external fluid flowing across the heat exchanger tube. A HVACR system includes a heat exchanger tube with a first heat exchange pass that at least partially combusts a fuel and has a modified shape.