Abstract: A Heating, Ventilating Air Conditioning (HVAC) fan control method to detect an HVAC fan is controlled by at least one fan-on duration control selected by a user and provide at least one fan-on alarm message prior to overriding the at least one fan-on duration control. The method monitors an occupancy sensor signal to determine an occupancy in a conditioned space served by an HVAC system and automatically overrides the at least one fan-on duration control to save energy when the conditioned space is unoccupied. The overriding may comprise operating the HVAC fan based only on a thermostat call for cooling or a thermostat call for heating, operating the HVAC fan for less time than the at least one fan-on duration control selected by the user, and operating the HVAC fan for less frequency than the at least one fan-on duration control selected by the user.

Abstract: The ionizer feedback control converts high-voltage signals to feedback signals to monitor the corresponding high-voltage signals and compares the feedback signals to a first specification to determine whether the feedback signals are within the first specification. The ionizer varies a frequency and a duty cycle of a digital signal to control an excitation signal for a step-up transformer and modulates the frequency and the duty cycle of a step-up transformer output voltage to consistently maintain the feedback signals within the first specification and maintain the high-voltage signals within a second specification to generate consistent ion concentrations over a range of electrical signal inputs. The microprocessor calculates and reports high-voltage signals, and ion concentrations based on feedback signals.

Abstract: A Heating, Ventilating Air Conditioning (HVAC) fan control method to detect an HVAC fan is controlled by at least one fan-on duration control selected by a user and provide at least one fan-on alarm message prior to overriding the at least one fan-on duration control. The method monitors an occupancy sensor signal to determine an occupancy in a conditioned space served by an HVAC system and automatically overrides the at least one fan-on duration control to save energy when the conditioned space is unoccupied. The overriding may comprise operating the HVAC fan based only on a thermostat call for cooling or a thermostat call for heating, operating the HVAC fan for less time than the at least one fan-on duration control selected by the user, and operating the HVAC fan for less frequency than the at least one fan-on duration control selected by the user.

Abstract: Detecting a thermostat call for heating or cooling based on detecting a heat W or compressor Y signal is activated and energizing a fan signal output and operating a system fan/blower while the W or Y signal is activated and energizing the fan signal and operating the fan for a variable fan-off delay immediately after the W or Y signal is de-activated and de-energizing the fan signal and not operating the fan after the variable fan-off delay when a fan G signal is not activated. Detecting the fan G signal is activated and the W or Y signal is not activated indicating a fan-on duration control selected by a user, and energizing the fan signal and operating the fan while the fan G signal is activated and de-energizing the fan signal and not operating the fan and not providing the variable fan-off delay when the fan G signal is de-activated.

Abstract: Detecting a thermostat call for heating or cooling based on detecting a heat W or compressor Y signal is activated and energizing a fan signal output and operating a system fan/blower while the W or Y signal is activated and energizing the fan signal and operating the fan for a variable fan-off delay immediately after the W or Y signal is de-activated and de-energizing the fan signal and not operating the fan after the variable fan-off delay when a fan G signal is not activated. Detecting the fan G signal is activated and the W or Y signal is not activated indicating a fan-on duration control selected by a user, and energizing the fan signal and operating the fan while the fan G signal is activated and de-energizing the fan signal and not operating the fan and not providing the variable fan-off delay when the fan G signal is de-activated.

Abstract: A method for providing a variable fan-off delay after a thermostat call for cooling or after a heating on cycle for a Heating, Ventilation, Air Conditioning (HVAC) system. The variable fan-off delay may be ended based on comparing a measurement of a Conditioned Space Temperature (CST) to a CST threshold. The CST threshold may be based on a previous measurement of the CST monitored during the current variable fan-off delay. The CST threshold may be an inflection point where the rate of change of the CST with respect to time equals zero plus or minus a confidence interval tolerance. The CST threshold may also be a fan-off delay differential offset or a thermostat setpoint differential where the variable fan-off delay is ended when the measurement of the CST during the variable fan-off delay crosses the differential at least once after the cooling or heating on cycle.

Abstract: A balanced bipolar ionizer that generates zero or nearly-zero ozone concentration by providing a bipolar ion concentration ratio greater than 80 percent based on a high-voltage output ratio less than 80 percent over a range of electric signal inputs. A signal-conditioning element provides an excitation signal to a step-up transformer which provides an output voltage to a positive and a negative voltage multiplier which provide a positive high-voltage output greater than an absolute value of a negative high-voltage output or vice versa. The high-voltage output ratio is equal to a minimum of an absolute value of a negative and positive high-voltage output divided by a maximum of the absolute value of the negative and positive high-voltage output. The bipolar ion-concentration ratio is equal to a minimum of an absolute value of a negative-ion and positive-ion concentration divided by a maximum of the absolute value of the negative-ion and positive-ion concentration.

Abstract: A fan-on Fault Detection Diagnostic (FDD) and correction method comprising at least one method selected from the group consisting of: detecting a Heating, Ventilating, Air Conditioning (HVAC) fan is controlled by a fan-on duration setting or a continuous or intermittent fan-on duration setting or schedule, and performing at least one action selected from the group consisting of: providing at least one fan-on alarm message, overriding the fan-on duration setting or the fan-on duration schedule, and turning off the HVAC fan for a fraction of the fan-on duration setting or schedule. Turning off the HVAC fan is based on at least one method selected from the group consisting of: a variable duration, skipping a scheduled fan-on duration setting, based on a call for cooling/heating, based on a geofencing or occupancy sensor signal, and based on a user-selected fan-on duration setting or a user-selected fan-off duration schedule.

Abstract: A Heating, Ventilating Air Conditioning (HVAC) fan control method comprising: detecting a HVAC fan is controlled by a fan-on setting, determining a HVAC fan-on operating time (F6) is greater than a Threshold Fan-on Time (TFT); and performing at least one action selected from the group consisting of: providing a HVAC fan-on alarm message, overriding the fan-on setting, and turning off the HVAC fan. The method may also include turning off an ultraviolet lamp after the HVAC fan is turned off, and turning on the ultraviolet lamp after the HVAC fan is turned on. Turning off the HVAC fan comprises: turning off the HVAC fan for a variable duration, skipping a scheduled fan-on setting, turning off the HVAC fan based on a call for cooling/heating, turning off the HVAC fan based on an indoor air quality measurement, and turning off the HVAC fan based on a geofencing or occupancy sensor signal.

Abstract: An economizer controller calibration method, comprising: sealing an economizer perimeter gap between the economizer frame and a Heating, Ventilating Air Conditioning (HVAC) system cabinet to reduce an uncontrolled outdoor airflow; determining a functional relationship between an economizer actuator voltage (x) and a damper position Outdoor Airflow Fraction (OAF) (y); monitoring the economizer actuator voltage (x) and measuring at least one airflow characteristic to calculate the damper position OAF (y) and obtain a set of x-versus-y data for at least two damper positions: closed, intermediate, and fully-open; calculating at least two coefficients of the functional relationship using the x-versus-y data; calculating a target economizer actuator voltage (xt) as a function of a required OAFr (yr) using the functional relationship; and positioning the damper using the target economizer actuator voltage (xt) to provide the target damper position OAFr (yr) within a tolerance of the required OAFr (yr).

Abstract: A method for controlling a Heating, Ventilation, Air Conditioning (HVAC) fan based on at least one Fault Detection Diagnostic (FDD) output wherein a previously monitored HVAC parameter is compared to a current HVAC parameter, and if a fault is detected, and impacts energy efficiency performance, then the FDD output is used to perform at least one action selected from the group consisting of: turning off a fan accidentally left on, and determining and providing a variable fan-off delay at the end of a heating or cooling cycle to improve energy efficiency, where both actions are based on HVAC parameters including, for example: a heating cycle duration, a cooling cycle duration, a conditioned space temperature and the rate of change of the HVAC parameters with respect to time. The method may be embodied in a fan controller, forced air unit control board, thermostat, or fan motor.

Abstract: A method for sealing an economizer perimeter gap to reduce an uncontrolled excess outdoor airflow by applying a sealing material over or into the economizer perimeter gap between the economizer frame and a Heating, Ventilating, Air Conditioning (HVAC) system cabinet comprising: locating the economizer perimeter gap between the economizer frame and the HVAC system cabinet and applying a sealing material over or into the economizer perimeter gap. The sealing material is selected from the group consisting of: an adhesive tape sealant, an adhesive sealant, a mastic sealant, a caulking material, and a weatherstripping. The method comprises: disconnecting an electrical power to the HVAC system, removing an economizer hood, locating and cleaning the metal services on both sides of the gap between the economizer frame and the HVAC cabinet, applying the sealing material over or into the gap, reinstalling the economizer hood, and reconnecting the electrical power to the HVAC system.

Abstract: A method for sealing an economizer perimeter gap to reduce an uncontrolled excess outdoor airflow by applying a sealing material over or into the economizer perimeter gap between the economizer frame and a Heating, Ventilating, Air Conditioning (HVAC) system cabinet comprising: locating the economizer perimeter gap between the economizer frame and the HVAC system cabinet and applying a sealing material over or into the economizer perimeter gap. The sealing material is selected from the group consisting of: an adhesive tape sealant, an adhesive sealant, a mastic sealant, a caulking material, and a weatherstripping. The method comprises: disconnecting an electrical power to the HVAC system, removing an economizer hood, locating and cleaning the metal services on both sides of the gap between the economizer frame and the HVAC cabinet, applying the sealing material over or into the gap, reinstalling the economizer hood, and reconnecting the electrical power to the HVAC system.

Abstract: An economizer controller calibration method, comprising: sealing an economizer perimeter gap between the economizer frame and a Heating, Ventilating Air Conditioning (HVAC) system cabinet to reduce an uncontrolled outdoor airflow; determining a functional relationship between an economizer actuator voltage (x) and a damper position Outdoor Airflow Fraction (OAF) (y); monitoring the economizer actuator voltage (x) and measuring at least one airflow characteristic to calculate the damper position OAF (y) and obtain a set of x-versus-y data for at least two damper positions: closed, intermediate, and fully-open; calculating at least two coefficients of the functional relationship using the x-versus-y data; calculating a target economizer actuator voltage (xt) as a function of a required OAFr (yr) using the functional relationship; and positioning the damper using the target economizer actuator voltage (xt) to provide the target damper position OAFr (yr) within a tolerance of the required OAFr (yr).

Abstract: A Fault Detection Diagnostic (FDD) correction method for increasing the cooling capacity delivered by an Air-Conditioning (AC) system with an economizer comprising: correcting/superseding at least one cooling fault/delay, the correcting/superseding selected from the group consisting of: correcting/superseding a High-limit-Shut-off-Temperature (HST) fault/delay based on detecting an Outdoor Air Temperature (OAT) is less than or equal to a High-limit-Control Temperature (HCT) during a thermostat call for cooling to enable economizer cooling otherwise delayed by the at least one HST fault/delay, superseding a thermostat second-stage time/temperature-deadband delay based on detecting an OAT is greater than or equal to an AC Control Temperature (ACT) during a call for cooling and energizing an AC compressor otherwise delayed by a thermostat second-stage time/temperature-deadband delay, superseding at least one economizer second-stage time/temperature delay based on detecting a thermostat second-stage cooling signa

Abstract: A method for controlling a Heating, Ventilation, Air Conditioning (HVAC) fan based on at least one Fault Detection Diagnostic (FDD) output wherein a previously monitored HVAC parameter is compared to a current HVAC parameter, and if a fault is detected, and impacts energy efficiency performance, then the FDD output is used to perform at least one action selected from the group consisting of: turning off a fan accidentally left on, and determining and providing a variable fan-off delay at the end of a heating or cooling cycle to improve energy efficiency, where both actions are based on HVAC parameters including, for example: a heating cycle duration, a cooling cycle duration, a conditioned space temperature and the rate of change of the HVAC parameters with respect to time. The method may be embodied in a fan controller, forced air unit control board, thermostat, or fan motor.

Abstract: Apparatus to continuously charge a smart thermostat battery and enable control of a 2-wire millivolt gas fireplace/heating system or a Heating, Ventilating, Air Conditioning (HVAC) system with at least one 24 VAC control voltage signal. The apparatus comprises one diode in a thermostat element or at least one terminal with a diode and a switch in the smart thermostat, and two diodes and a switch device in a switch element. The apparatus is configured to conduct a rectified current signal to charge the smart thermostat battery, and the at least one rectified 24 VAC control voltage signal to energize the switch device to control a HVAC system. The apparatus may be integrated into a smart thermostat with a graphical display to provide simple instructions to easily install the apparatus and the smart thermostat for a HVAC system without a common wire or a 2-wire millivolt gas fireplace/heating system.

Abstract: A solid-state common-wire adapter combines two Heating, Ventilating, Air Conditioning (HVAC) control signals on a single pre-existing wire to allow another pre-existing wire to be used as a common-wire to provide reliable power to a Smart Communicating Thermostat. The solid-state common-wire adapter may comprise a thermostat element with at least one diode and an HVAC element with at least one device selected from the group consisting of: a solid-state TRIode for Alternating Current (TRIAC), a capacitor, a microprocessor, a power supply, an optoisolator, and a load resistor. Smart Communicating Thermostats require continuous power for communicating with a wireless network, providing a Liquid Crystal Display (LCD) display, and controlling an HVAC system. Some Smart Communicating Thermostats use power stealing which is unreliable. The solid-state common-wire adapter is reliable, small, low-cost, and easy to install.

Abstract: A Fault Detection Diagnostic (FDD) correction method for increasing the cooling capacity delivered by an Air-Conditioning (AC) system with an economizer comprising: correcting/superseding at least one cooling fault/delay, the correcting/superseding selected from the group consisting of: correcting/superseding a High-limit-Shut-off-Temperature (HST) fault/delay based on detecting an Outdoor Air Temperature (OAT) is less than or equal to a High-limit-Control Temperature (HCT) during a thermostat call for cooling to enable economizer cooling otherwise delayed by the at least one HST fault/delay, superseding a thermostat second-stage time/temperature-deadband delay based on detecting an OAT is greater than or equal to an AC Control Temperature (ACT) during a call for cooling and energizing an AC compressor otherwise delayed by a thermostat second-stage time/temperature-deadband delay, superseding at least one economizer second-stage time/temperature delay based on detecting a thermostat second-stage cooling signa

Abstract: A Heating, Ventilating Air Conditioning (HVAC) fan control method comprising: detecting a HVAC fan is controlled by a fan-on setting, determining a HVAC fan-on operating time (F6) is greater than a Threshold Fan-on Time (TFT); and performing at least one action selected from the group consisting of: providing a HVAC fan-on alarm message, overriding the fan-on setting, and turning off the HVAC fan. The method may also include turning off an ultraviolet lamp after the HVAC fan is turned off, and turning on the ultraviolet lamp after the HVAC fan is turned on. Turning off the HVAC fan comprises: turning off the HVAC fan for a variable duration, skipping a scheduled fan-on setting, turning off the HVAC fan based on a call for cooling/heating, turning off the HVAC fan based on an indoor air quality measurement, and turning off the HVAC fan based on a geofencing or occupancy sensor signal.