A heat recovery ventilator (HRV) and/or energy recovery ventilator (ERV) that integrates with a residential capacity air handling unit (AHU) is embodied in a small footprint HRV or ERV unit that connects directly to the return side of an AHU and to outdoor air inlet and exhaust ducts. The ventilator includes a control system incorporating a processor and sensors that control the operation of the system to provide desired ventilation flow rates under varying conditions.

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.

A method for calibrating a product fluid flow valve disposed along a flow path in a site duct, and including damper blades, an actuator coupled thereto, a differential pressure sensor, and a blade controller adapted to define adjustable product flow apertures, comprising the steps: with a calibration fluid flow valve in a calibration duct remote from the product fluid flow valve, and characterized by a geometric shape and operational parameters corresponding to those of the product fluid flow valve, and with a calibration controller, establishing a plurality of calibration conditions including pressure drop across the calibration blades and area of the calibration apertures, determining a calibration flow rate (CFM) function, transferring the CFM function to the product blade controller and adjusting the adjustable product flow apertures so that a parameter set point is attained. In a form, fluid flowing through the product flow apertures forms a vena contracta.

An animal house climate control system uses a method for operating a baffle of an air inlet of an animal house with a motor using timed inlet control. The method includes performing a calibration sequence to calculate opening velocity and opening inertia values and closing velocity and closing inertia values. The method also includes moving the baffle from an initial position to a final position by calculating a calculated power on time for the motor using the opening inertia or closing inertia values. The method can also include calculating a real position error value by comparing the calculated on time for the motor and a measured on time for the motor and using the real position error value to calculate adjusted opening and closing velocity values.

An air conditioning system includes one or more cameras, one or more air conditioning operation units, and an air conditioner control unit that obtains, via the one or more cameras, images of a surrounding environment of the air conditioning operation units, and determines a first set of factors, including a layout of the surrounding environment, based on analysis of the images through predefined machine learning models. The control unit, in accordance with the first set of factors that has been determined based on the analysis of the images through the predefined machine learning models, selects a first operation profile from a plurality of predefined operation profiles to control the air conditioning operation units.

A method is provided for controlling airflow into a furnace that employs a velocity type damper. In one embodiment, the method for controlling airflow may include engaging a velocity type damper to an air port opening of a furnace. The velocity type damper includes at least one air controlling surface that is positioned proximate to a wall of the furnace at the air port opening so that air velocity exiting the at least one air controlling surface is substantially equal to the air velocity entering the air port opening to the furnace. The method may further include adjusting a cross sectional area through the velocity type damper to control air velocity into the furnace through the air port opening.

An air conditioner indoor unit includes a housing having an air inlet, a first air outlet, and a second air outlet arranged below the first air outlet, and an air output door assembly arranged at the second air outlet and connected to the housing. At least a portion of the air output door assembly is configured to move relative to the housing to form an air output channel between the at least a portion of the air output door assembly and the housing. The air output channel has a ring-shaped air output end located in front of the second air outlet. The air conditioner indoor unit further includes an opening-closing mechanism movably mounted at the air output door assembly and configured to open or close an air regulation channel area that includes an upper part of the air output channel.

A method of controlling a ceiling type air conditioner including a panel located on a ceiling surface, outlets formed at positions corresponding to four sides of the panel, a first vane group for opening and closing the outlets located at two opposing sides, and a second vane group for opening and closing the outlets located at the other two opposing sides includes performing a dynamic airflow mode in which an indoor temperature reaches a set temperature by controlling rotation angles of the first vane group and the second vane group, and calculating a pleasant airflow index Y for determining a pleasant feeling of a user at the set temperature. The pleasant airflow index is calculated using the indoor temperature, the rotation angle of the first vane group or the second vane group, an air volume, a distance from a floor surface and an airflow position as variables.

A condenser fan assembly includes a first condenser fan and a first motor coupled to the first condenser fan via a first shaft, where the first motor is configured to drive rotation of the first condenser fan via the first shaft, and a second condenser fan and a second motor coupled to the second condenser fan via a second shaft, where the second motor is configured to drive rotation of the second condenser fan via the second shaft. The condenser fan assembly also includes a fan rotation restrictor configured to selectively block and enable rotation of the first shaft.

The present disclosure describes a supply fan assembly including a controller, a memory operably coupled with the controller. The supply fan assembly further includes at least one environment sensor operably coupled with the controller and a fan supplying fresh air from an exterior environment into a structure according to instructions from the controller. Additionally, the operational data is generated by the at least one of the environment sensor and the controller, and the controller instructs the fan in response to the operational data generated during a pre-defined time period.