Abstract: An air conditioning system to improve indoor air quality (“IAQ”) comprises an air conditioner to receive indoor air from an indoor space and to heat or cool the air, the air conditioner to then return conditioned air to the indoor space. An IAQ option board (“IOB”), electrically coupled to the air conditioner control board, is configured to accept electrical inputs from at least one IAQ sensor. A fresh air damper is electrically connected to the IOB, the IOB controlling the position of the fresh air damper valve. An air purifier is situated such that air from the indoor space passes through the purifier. The operation of state of operation of the purifier is based at least in part on the input from at least one IAQ sensor to improve the IAQ of the indoor space.

Abstract: An environmental control system (ECS) for an aircraft may be employed to regulate temperature of air entering a cabin of the aircraft. During conditioning of the air, condensate may form in the air. A multiple-stage condensate extraction unit may be incorporated into the ECS to remove the condensate. The extraction unit may be provided with two fluid collection stages built into a cylindrical duct. The duct may have a bend therein. One of the collection stages may be positioned on an upstream side of the bend while the second one of the stages may be positioned on a downstream side thereof. The combination of the two stages and their positioning on either side of the bend may provide a particularly compact and efficient condensate extraction unit.

Abstract: A method of balancing the supply of bleed air from a plurality of gas turbine engines, there being an air bleed line from each of the engines to a common distribution line which distributes the bled air to at least one ancillary system, each air bleed line including a control valve which is controllable by a controller to vary the flow rate of air bled from the associated engine, the method including providing to the controller a demand signal indicative of the demand for bleed air by the ancillary system, sensing air pressure in the distribution line and comparing the demand signal with the sensed air pressure to derive a command signal, flow rates the air pressure individually in each of the air bleed lines from the engines with respective air flow rate sensors which provide air flow rate signals to the controller, comparing the air flow rates in each of the air bleed lines to derive individual flow matching signals for each of the engines, comparing each of the flow matching signals to the command signal t