Abstract: Methods for controlling an economizer of an HVAC system are disclosed. An illustrative control method may include positioning one or more controllable dampers in first and second configurations such that a mixed air stream has first and second mixing ratios of incoming outside air to return air. First and second measures related to the temperature of the mixed air stream may be recorded when the dampers are in each of the first and second configurations. Based on the recorded first and second measures, it may be determined whether and/or how much of the incoming outside air to admit into the economizer via the one or more controllable dampers during subsequent operation of the HVAC system.

Abstract: The present disclosure provides a method for controlling an economizer of an HVAC system. The economizer has an outside air stream of incoming outside air, a return air stream of return air, and a mixed air stream of mixed incoming outside air and return air that is provided to the cooling unit of the HVAC system. The economizer also includes one or more controllable dampers for controlling a mixing ratio of incoming outside air to return air in the mixed air stream. The control method includes positioning the one or more controllable dampers in first and second configurations such that the mixed air stream has first and second mixing ratios of incoming outside air to return air in the mixed air stream. The method also includes recording first and second measures related to the temperature of the mixed air stream when the dampers are in each of the first and second configurations. First and second measures related to other parameters of the mixed air stream may be recorded as well.

Abstract: An economizer controller system having a plug and play recognition approach with an automatic user interface population mechanism. A check may be made for sensors connected to the controller. The control type of the sensors may be determined. The menu structure may be repopulated based on the control type. The user interface may then be updated. This approach may be repeated as needed.

Abstract: Demand ventilation protocols can address the issue of sensor failure while still providing desirable levels of energy conservation. An occupancy indicator such as a sensor can be monitored. If the sensor reading is determined to be incorrect, unexpected or otherwise erroneous, the ventilation system can provide an amount of fresh air sufficient for adequate ventilation without over-ventilating the building.

Abstract: A method and system for operating a demand control ventilation system with a multi-speed fan is disclosed. The control system may modulate the fan speed of a multi-speed fan and/or the position of a ventilation damper in order to achieve desired ventilation levels for a building.

Abstract: Methods and systems for automatically calibrating one or more damper positions of a demand control ventilation system are disclosed. In one illustrative embodiment, a demand control ventilation system includes a damper for controlling a flow of outside air into a building. A controller may be programmed to automatically execute a calibration algorithm from time to time to calibrate one or more calibration damper positions such that a predetermined flow of outside air is drawn through the damper and into the building at each of the one or more calibration damper positions. This calibration can, in some instances, help increase the efficiency and/or utility of the demand control ventilation system.

Abstract: The disclosure relates to a Demand Control Ventilation (DCV) and/or Economizer system that is capable of drawing outside air into an HVAC air stream. In some instances, the DCV and/or Economizer system may be configured to help perform one or more system checks to help verify that the system is functioning properly. In some instances, the DCV and/or Economizer system may provide some level of manual control over certain hardware (e.g. dampers) to help commission the system. The DCV and/or Economizer system may store one or more settings and or parameters used during the commissioning process (either in the factory or in the field), so that these settings and/or parameters may be later accessed to verify that the DCV and/or Economizer system was commissioned and commissioned properly.

Abstract: The present disclosure provides a method for operating an HVAC system for conditioning air of an inside space. The HVAC system has an economizer configured to control the intake of outside air into an HVAC air stream of the HVAC system. The method includes determining at least two parameters of the air of the inside space, where the at least two parameters are selected from a set of parameters from which an inside air dry bulb temperature, an inside air dew point, an inside air relative humidity, and an inside air enthalpy can be determined, either directly or indirectly. The method also includes determining at least two parameters of the outside air, where the at least two parameters being selected from a set of parameters from which an outside air dry bulb temperature, an outside air dew point, and an outside air enthalpy can be determined, either directly or indirectly.

Abstract: The present disclosure provides a method for controlling an economizer of an HVAC system. The economizer has an outside air stream of incoming outside air, a return air stream of return air, and a mixed air stream of mixed incoming outside air and return air that is provided to the cooling unit of the HVAC system. The economizer also includes one or more controllable dampers for controlling a mixing ratio of incoming outside air to return air in the mixed air stream. The control method includes positioning the one or more controllable dampers in first and second configurations such that the mixed air stream has first and second mixing ratios of incoming outside air to return air in the mixed air stream. The method also includes recording first and second measures related to the temperature of the mixed air stream when the dampers are in each of the first and second configurations. First and second measures related to other parameters of the mixed air stream may be recorded as well.

Abstract: Demand ventilation protocols can address the issue of sensor failure while still providing desirable levels of energy conservation. An occupancy indicator such as a sensor can be monitored. If the sensor reading is determined to be incorrect, unexpected or otherwise erroneous, the ventilation system can provide an amount of fresh air sufficient for adequate ventilation without over-ventilating the building.