The disclosed technology includes devices and systems for an economizer of a heating ventilation and air conditioning (HVAC) system. The disclosed technology can include an economizer for an HVAC system comprising a housing, an air inlet extending through a wall of the housing, a sliding door configured to transition between a closed position and an open position, and a controller configured to cause the sliding door to transition between the closed position and the open position based on temperature data. The sliding door can comprise a first portion forming a barrier and a second portion comprising at least one aperture. In the closed position, the first portion can align with the air inlet and substantially prevent ambient air from moving through the air inlet. In the open position, the second portion can align with the air inlet and permit the ambient air to move through the air inlet.

An air supply system comprising at least two bleed sources configured to provide bleed air, wherein each bleed source comprises an engine or an auxiliary power unit and an oil as lubricant for the engine or the auxiliary power unit. The system also includes at least one air conditioning pack for cooling the bleed air from the bleed sources, and a plurality of bleed ducts, wherein each bleed duct connects one of the bleed sources to the at least one air conditioning pack. The system further comprises a plurality of detectors, wherein each detector is associated with a bleed source and the plurality of detectors are configured for detecting substances specific for the oil.

An air conditioning system using a fuel cell system can reduce energy consumption for air conditioning and can use the electricity produced by operating the fuel cells, where a fuel cell blower that is used to operate fuel cells is also used for air conditioning. The air conditioning system includes an air intake line connected between an interior and an exterior of a building; an air blower disposed in the air intake line to supply external air to the interior; a first intake shut-off valve for opening or closing the air intake line; a fuel cell system receiving air in the interior by operation of the fuel cell blower and producing electrical energy; and a controller controlling operation of the first intake shut-off valve to open the air intake line when the fuel cell system is operated.

An indoor pollution prevention system includes a plurality of gas detection modules, one or more intelligent control-driving processing devices, one or more gas-exchange processing devices, one or more intake passages, and one or more discharge passages. The intake passage is connected to the gas-exchange processing device and has an intake opening for guiding the outdoor gas into an indoor space. The discharge passage is connected to the gas-exchange processing device and has a discharge opening for discharging the air pollution source to the outdoor space. The intelligent control-driving processing device controls the gas-exchange processing device to be enabled under a surveillance condition of the gas detection module, so that the air pollution source passes through the discharge passage, filtered and purified by a cleaning and filtration assembly, and is discharged to the outdoor space, thereby allowing the indoor space to have a clean air.

An air conditioner unit includes a housing with an outdoor heat exchanger assembly and an indoor heat exchanger assembly therein. A makeup air intake duct an a makeup are exhaust duct are disposed above the housing parallel to each other. The air conditioner unit also includes a heat exchanger having a first coil and a second coil. The first coil is disposed within the makeup air intake duct. The second coil is disposed with the makeup air exhaust duct. The heat exchanger also includes a first pipe connecting an outlet of the first coil to an inlet of the second coil and a second pipe connecting an outlet of the second coil to an inlet of the first coil.

A heating control device includes an estimating unit to estimate a latent heat load of air present in a ventilation target space as a ventilation target and a heating control unit to control, in accordance with the latent heat load estimated by the estimating unit, a temperature of heating outside air by a heat exchanger to heat outside air supplied to the ventilation target space, via control of a condensation temperature of a refrigerant in the heat exchanger. The estimating unit estimates the latent heat load from ΔX, which is a value obtained by subtracting, from a target absolute humidity (X0) set by a temperature/humidity setting device to set a target humidity of an interior as the ventilation target space, an absolute humidity (Xi) of the interior detected by an indoor humidity sensor.

Apparatus and method of heating and ventilating an enclosed area comprising a floor arranged as a number of floor zones. The method comprises providing a radiant heater spaced above each floor zone so as in use to direct heat downwards towards the floor; providing a ventilating air inlet spaced above at least part of each floor zone, the air inlet being at the same level as, or closer to, the floor than the radiant heater, the air inlet being arranged in use to draw-in a controllable quantity of air from outside of the enclosed area; providing a ventilating air outlet spaced above at least part of each floor zone, the air outlet being spaced further from the floor than the radiant heater and air inlet, the air outlet being arranged in use to extract a controllable quantity of air from inside of the enclosed area, wherein the method further comprises, for each floor zone, independently controlling the quantity of air being drawn in and extracted from said floor zone based on the sensed temperature inside and outside the enclosed space.

An indoor pollution prevention system includes a plurality of gas detection modules, one or more intelligent control-driving processing devices, one or more gas-exchange processing devices, and one or more indoor cleaning and filtration devices. The gas-exchange processing device includes one or more flow-guiding component and a cleaning and filtration assembly. The intelligent control-driving processing device controls the operation of the indoor cleaning and filtration device in real-time under a surveillance condition, therefore the air pollution source in the indoor space passes through the indoor cleaning and filtration device, allowing the air pollution source in the indoor space to be filtered and exchanged to become a clean air.

Embodiments of the present disclosure include methods and systems of circulating air in an enclosed environment. In such embodiments, the system may comprise an air handling unit (AHU), the AHU including an indoor air inlet to receive an indoor airflow from the enclosed environment and an indoor air outlet to expel the indoor airflow, a conditioning element arranged between the inlet and the outlet configured to at least heat or cool the indoor airflow as it flows thereover, one or more fan units arranged between the inlet and the outlet configured to provide velocity to the indoor airflow, and an air treatment assembly (ATA) arranged within or proximate the AHU, the ATA including an air inlet configured to receive a portion of the indoor airflow received by the AHU indoor air inlet.

A ventilation system with: (i) a volumetric enclosure having an inlet and an outlet and for coupling to an interior of a building habitable by human occupants; (ii) a fan located within the volumetric enclosure and for drawing air exterior to the building and supplying the air to the interior of the building; (iii) a programmable control apparatus for enabling and disabling the fan in response to a plurality of parameters, at least some of the parameters relating to quality of air to me moved in response to the fan; and (iv) circuitry coupled between the inlet and the outlet for measuring a signal representative of a volume of air passing through the volumetric enclosure over a period of time.