Systems and methods for air flow circulation are described which utilize one or more air conditioning units as well as transfer grilles to move cooler air from one space to another. The transfer grilles can include bi-directional in-line fans to move air between spaces in discrete ducts located between the spaces. Motorized dampers can be controlled by a controller that receives information about various rooms and areas from temperature and occupancy sensors within those rooms or areas. In this manner, conditioned air can be directed to those rooms that are occupied and whose temperature needs correction based on a thermostat setting, and use of the air conditioning unit can be avoided when a cool air source is present in another space.

An air conditioner includes a main body including a body fan, a heat exchanger, and a body housing. A ventilation hose connects the main body to outdoor air. A ventilation module is attached to an outer side of the body housing, and includes a ventilation fan. The ventilation module switches between an exhaust mode in which indoor air is exhausted to the outdoors through the ventilation hose and an air supply mode in which outdoor air is supplied to the main body through the ventilation hose.

A space cleaning system includes: a detection unit configured to detect generation and a generation position of an infectious substance in a space; an airflow control unit configured to generate an airflow towards the generation position detected in response to detection of the generation of the infectious substance; and a cleaning control unit configured to clean the space at least after the generation of the infectious substance is detected.

An air handling device includes a plurality of tunnels defining a plurality of separate air flow pathways. At least one tunnel of the plurality of tunnels is an active tunnel and at least one tunnel of the plurality of tunnels is a redundant tunnel. The air handling device further includes a first air select at a first end of the plurality of tunnels and a second air select on a second end of the plurality of tunnels, wherein the first end is opposite to the second end. The air handling device also includes a plurality of dampers within each of the first and second air selects, wherein the plurality of dampers are configured to change an air flow therein to block air flow through the active tunnel and allow air flow through the redundant tunnel.

Air gap insulation is a common means of providing thermal insulation from the environment. In many cases the air gap is heated by direct or indirect solar radiation, so ventilating this gap has a cooling effect. The invention cools this gap by integrating moisture-absorption material units that harvest water from the air during the night and provide evaporative cooling during the day. Compared to the ambient air, the daily relative humidity fluctuations in the air gap are more extreme, allowing a significant cooling effect. Furthermore, during the night, humidity absorption on the absorption unit reduces the risk of condensation within the air gap. Additionally the absorption process generates heat, and by using a controller processes of heating, cooling and dehumidifying can be activated when possible and needed.

This patent presents a method, and some devices based on the method, to achieve near zero air based transmission of disease within a business, while still allowing people to approach each other closer than arms length touching distance. This can be achieved with rapidly deployable portable units. It also presents a simple method to test whether the airflow structure requirements of the system have been met, and to adjust it if not.

The humidity control unit includes: an air passage through which a first space which is a target space and a second space communicate with each other; a moisture absorber arranged in the air passage and configured to absorb moisture from air and desorb the moisture to the air; a heat source arranged in the air passage and configured to at least cool or heat the moisture absorber; an air transport mechanism configured to allow the air in the air passage to flow in reverse directions; and a controller configured to control the heat source and the air transport mechanism.

A device for controlling air flow in an air duct comprises a rotary, profiled damper, a fan or turbine, and an actuator. The profiled damper comprises two rotatable integral canopies, a central opening therebetween, flat ribs extending outwardly from the canopies and towards an interior of the air duct, wherein an axis of rotation of said canopies coincides with an axis of rotation of the profiled damper and the canopies are arranged on the opposite sides of the profiled damper. The profiled damper is characterized in that the actuator is configured to reverse a position of the profiled damper, thereby reversing a direction of an air stream generated by the fan or turbine.

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 (x.sub.t) as a function of a required OAF.sub.r (y.sub.r) using the functional relationship; and positioning the damper using the target economizer actuator voltage (x.sub.t) to provide the target damper position OAF.sub.r (y.sub.r) within a tolerance of the required OAF.sub.r (y.sub.r).

A two-part reversible air deflector for reversing the flow direction of air pumped by a radial fan with constant rotation direction and a ventilation system formed of ventilation installations with use of reversible air deflectors, wherein the air deflector is divided into the suction-inlet body and the separate compression-outlet body, each of them having the frontal through opening surrounded with an annular protrusion wherein both bodies and of the deflector are arranged opposite a fixed partition having a round through opening with its edge of a funnel outline surrounded on two sides with a pair of annular protrusions in such a manner that the common axis X of frontal openings of the bodies is aligned with the axis of the round opening of the partition.