For environment control systems utilizing centralized controllers, attention should be paid
to how the controller interacts with the building’s air inlet system. In many older facilities
there is no air inlet control except perhaps one or more hand cranks to adjust inlet (or
curtain) width. New facilities typically use air inlet controllers that work to maintain a
constant static pressure difference between inside and outside. This type of system is
11.3
easy to use with virtually any environmental control system because the air inlet
controller automatically adjusts inlets as the number of fans operating changes.