Abstract: A heating, ventilating, and air conditioning (HVAC) system includes at least one indoor air quality monitor. The indoor air quality monitor is formed with an arrangement of chambers—intake chamber, low-flow chamber, and outlet chamber—such that a particulate sensor on an interior and another air quality sensor are neither overwhelmed nor underwhelmed by air flow to the sensors. The indoor air quality monitor may be arranged for attaching to a surface in a conditioned space for sampling air therein or may include a bypass chamber that fluidly couples to an HVAC duct.

Abstract: A controller is configured to operate a heating, ventilation, and air conditioning (HVAC) system based on a measurement of a detected quantity of particulate matter from an air quality sensor in relation to a threshold value.

Abstract: A controller is configured to operate a heating, ventilation, and air conditioning (HVAC) system based on a first plurality of particulate matter measurements and a second plurality of particulate matter measurements. The controller is configured to determine an air filter efficiency for an air filter based on the received first plurality of particulate matter measurements and the received second plurality of particulate matter measurements. The controller is further configured to determine if a quantity of particulate matter in an airflow exceeds a first threshold value based on the received second plurality of particulate matter measurements. In response to determining that the quantity of particulate matter in the airflow does exceed the first threshold value, the controller is configured to transmit a notification indicating an action to inspect the air filter.

Abstract: The disclosure provides a method of operating a (HVAC) system. The method includes measuring a concentration of a gas in the target space, and determining that the concentration exceeds a gas concentration threshold. The method includes determining that operation of the HVAC system in a ventilation mode is indicated to reduce the concentration of the gas. The method includes determining a total capacity of the HVAC system, and determining a current capacity of the HVAC system. The method includes causing the HVAC system to operate in the ventilation mode after validating that the total capacity is greater than the current capacity during operation of the HVAC system in the ventilation mode.

Abstract: An air quality measuring device that includes a first chamber, a second chamber, a third chamber, and a fourth chamber. The first chamber includes a first inlet configured to receive a first airflow, a first outlet configured to receive a first portion of the first airflow, and a second outlet configured to receive a second portion of the first airflow. The second chamber includes a second inlet configured to receive the first portion of the first airflow and a first sensor disposed within the second chamber. The third chamber includes a third inlet configured to receive the second portion of the first airflow and a second sensor disposed within the third chamber. The fourth chamber includes a fourth inlet configured to receive the second portion of the first airflow and a third sensor disposed within the fourth chamber.

Abstract: An indoor air quality monitor for an HVAC system includes a monitor body formed with a plurality of chambers defined at least in part by chamber walls. A bypass chamber allows for a majority of airflow entering the monitor to pass through. An intake chamber coupled to the bypass chamber allows for a portion of air to be removed for sampling by a particulate sensor. Air from the particulate sensor is discharged to an outlet chamber that is fluidly coupled to a downstream portion of the bypass chamber. The fluid requirements of the particulate sensor are maintained without overwhelming or underwhelming the particulate sensor.

Abstract: An air quality measuring device that includes a first chamber, a second chamber, a third chamber, and a fourth chamber. The first chamber includes a first inlet configured to receive a first airflow, a first outlet configured to receive a first portion of the first airflow, and a second outlet configured to receive a second portion of the first airflow. The second chamber includes a second inlet configured to receive the first portion of the first airflow and a first sensor disposed within the second chamber. The third chamber includes a third inlet configured to receive the second portion of the first airflow and a second sensor disposed within the third chamber. The fourth chamber includes a fourth inlet configured to receive the second portion of the first airflow and a third sensor disposed within the fourth chamber.

Abstract: A controller is configured to operate a heating, ventilation, and air conditioning (HVAC) system based on a plurality of concentration measurements received from a gas sensor, wherein the gas sensor is disposed within a sensor housing upstream of an evaporator coil. The controller is configured to receive the plurality of concentration measurements and determine if a concentration of total volatile organic compounds (TVOCs) in an airflow exceeds a first threshold value. The controller is further configured to operate the HVAC system in a second mode of operation to increase ventilation in response to determining that the concentration of TVOCs in the airflow does exceed the first threshold value, wherein a volume of air is introduced into and discharged from the HVAC system during the second mode of operation.

Abstract: A controller is configured to operate a heating, ventilation, and air conditioning (HVAC) system based on a first plurality of particulate matter measurements and a second plurality of particulate matter measurements. The controller is configured to determine an air filter efficiency for an air filter based on the received first plurality of particulate matter measurements and the received second plurality of particulate matter measurements. The controller is further configured to determine if a quantity of particulate matter in an airflow exceeds a first threshold value based on the received second plurality of particulate matter measurements. In response to determining that the quantity of particulate matter in the airflow does exceed the first threshold value, the controller is configured to transmit a notification indicating an action to inspect the air filter.

Abstract: A heating, ventilating, and air conditioning (HVAC) system includes at least one indoor air quality monitor. The indoor air quality monitor is formed with an arrangement of chambers—intake chamber, low-flow chamber, and outlet chamber—such that a particulate sensor on an interior and another air quality sensor are neither overwhelmed nor underwhelmed by air flow to the sensors. The indoor air quality monitor may be arranged for attaching to a surface in a conditioned space for sampling air therein or may include a bypass chamber that fluidly couples to an HVAC duct. Other systems and methods are presented.

Abstract: An indoor air quality monitor for an HVAC system includes a monitor body formed with a plurality of chambers defined at least in part by chamber walls. A bypass chamber allows for a majority of airflow entering the monitor to pass through. An intake chamber coupled to the bypass chamber allows for a portion of air to be removed for sampling by a particulate sensor. Air from the particulate sensor is discharged to an outlet chamber that is fluidly coupled to a downstream portion of the bypass chamber. The fluid requirements of the particulate sensor are maintained without overwhelming or underwhelming the particulate sensor. Other systems and monitors are presented; some include separate TVOC sensors.

Abstract: An HVAC system includes one or more air quality sensors, each configured to measure an air quality and a thermostat communicatively coupled to the one or more air quality sensors. The thermostat receives indoor air quality measurements from the one or more air quality sensors. An indoor air quality score is determined based at least in part on the received indoor air quality measurements. The thermostat determines, based at least in part on the indoor air quality score, a mitigation action, wherein the mitigation action comprises one or more actions selected from the group of: (i) a filtering action comprising filtering air provided to the space using an air purification subsystem, and (ii) a ventilation action comprising ventilating the space using a ventilation subsystem. The mitigation action is executed, or implemented, by adjusting one or more components of the HVAC system.

Abstract: An air quality measuring device that includes a first chamber, a second chamber, a third chamber, and a fourth chamber. The first chamber includes a first inlet configured to receive a first airflow, a first outlet configured to receive a first portion of the first airflow, and a second outlet configured to receive a second portion of the first airflow. The second chamber includes a second inlet configured to receive the first portion of the first airflow and a first sensor disposed within the second chamber. The third chamber includes a third inlet configured to receive the second portion of the first airflow and a second sensor disposed within the third chamber. The fourth chamber includes a fourth inlet configured to receive the second portion of the first airflow and a third sensor disposed within the fourth chamber.

Abstract: A pressure probe includes a tube having an output end, an internal passage, an axial run, and pressure orifices axially aligned along a downstream side of the axial run. The pressure orifices are in communication with the output end through the internal passage and an upstream side of the axial run that is opposite from the downstream side of the axial run and does not include a pressure orifice. The downstream side is perpendicular to airflow.

Abstract: A pressure probe includes a tube having an output end, an internal passage, an axial run, and pressure orifices axially aligned along a downstream side of the axial run. The pressure orifices are in communication with the output end through the internal passage and an upstream side of the axial run that is opposite from the downstream side of the axial run and does not include a pressure orifice. The downstream side is perpendicular to airflow.

Abstract: In an embodiment, the present disclosure pertains to a pressure probe. In some embodiments, the pressure probe includes a tube having an output end, an internal passage, an axial run, and pressure orifices axially aligned along a downstream side of the axial run. In some embodiments, the pressure orifices are in communication with the output end through the internal passage and an upstream side of the axial run that is opposite from the downstream side of the axial run and does not include a pressure orifice. Additionally, in some embodiments, the downstream side is perpendicular to airflow.

Abstract: In an embodiment, the present disclosure pertains to a pressure probe. In some embodiments, the pressure probe includes a tube having an output end, an internal passage, an axial run, and pressure orifices axially aligned along a downstream side of the axial run. In some embodiments, the pressure orifices are in communication with the output end through the internal passage and an upstream side of the axial run that is opposite from the downstream side of the axial run and does not include a pressure orifice. Additionally, in some embodiments, the downstream side is perpendicular to airflow.

Abstract: In an embodiment, the present disclosure pertains to a pressure probe. In some embodiments, the pressure probe includes a tube having an output end, an internal passage, an axial run, and pressure orifices axially aligned along a downstream side of the axial run. In some embodiments, the pressure orifices are in communication with the output end through the internal passage and an upstream side of the axial run that is opposite from the downstream side of the axial run and does not include a pressure orifice. Additionally, in some embodiments, the downstream side is perpendicular to airflow.

Abstract: A method includes initiating, by a controller of a heating, ventilation, and air conditioning (“HVAC”) system, a filter calibration procedure, curve fitting a first line based on a plurality of static pressure measurements and corresponding flowrates of air, and generating a second line based on the first line. The method further includes determining a first static pressure measurement sensed by at least one sensor in response to determining that a first flowrate of air has been moved by the at least one blower and comparing the first static pressure value to a predicted static pressure value of the second line, the predicted static pressure value corresponding to the first flowrate of air. The method further includes determining that an air filter of the HVAC system has no more usable life in response to determining that the first static pressure value is greater than the predicted static pressure value.

Abstract: A method includes initiating, by a controller of a heating, ventilation, and air conditioning (“HVAC”) system, a filter calibration procedure, curve fitting a first line based on a plurality of static pressure measurements and corresponding flowrates of air, and generating a second line based on the first line. The method further includes determining a first static pressure measurement sensed by at least one sensor in response to determining that a first flowrate of air has been moved by the at least one blower and comparing the first static pressure value to a predicted static pressure value of the second line, the predicted static pressure value corresponding to the first flowrate of air. The method further includes determining that an air filter of the HVAC system has no more usable life in response to determining that the first static pressure value is greater than the predicted static pressure value.