Part 2 examines two methods of controlling the supply fan to minimise static pressure. without sacrificing comfort or adequate ventilation. Both methods make use of feedback from local zone flow control loops, which has recently become possible with the introduction of direct digital control terminal boxes. States that preliminary evaluation of proposed static pressure minimisation control algorithms using simulation yielded encouraging results, showing that such a strategy is feasible in systems combining VSDs and DDC terminal boxes.

KEYWORDS: Fans, ventilation, energy conservation, modernising, controls, calculating, air flow, variable volume air conditioning, offices, case studies, pressure, algorithms, static pressure, computer controls, models