Examines the key components of ventilation and air conditioning air systems, with emphasis on how to select plant and design ductwork distribution circuits, air diffusers and controls to provide acceptable indoor comfort conditions while minimising energy consumption. This subject introduces the student to the engineering design of air systems in buildings. It encompasses the design and installation requirements of air systems including modern heat recovery technology design features.
VENTILATION AIR REQUIREMENTS: Recommended fresh air rates, natural/mechanical ventilation applications, air quality, exhaust air requirements, impact of ventilation air requirements on heating and cooling loads calculations.
ROOM AIR DISTRIBUTION: Human comfort criteria, grille & diffuser types and application, impact of air change rate per hour on diffuser selection, throw, terminal velocity, & noise criteria design requirements, effects of heating and/or cooling mode of operation on diffuser performance.
AIR FLOW AND PRESSURES IN DUCTWORK SYSTEMS: Total, Velocity & Static pressures in a ductwork system, plotting pressure flow diagrams, pressure loss factors for fittings, equal pressure drop limiting velocity ductwork and fan sizing.
SINGLE ZONE CAV AIR CONDITIONING SYSTEMS: Air properties, review and plotting of basic processes, winter & summer psychrometric cycles and calculations, single & multiple zone constant volume terminal reheat systems, zoning, calculation of plant heating, humidification & cooling loads, fresh air requirements, room sensible & latent heat gains, full fresh, recirculation system AHU configurations, modifications to reduce cooling and heating loads.
COMMISSIONING: Air commissioning, pre-commissioning checks, measurement of air flow/pressure drop, damper characteristics, commissioning tolerances, theory of proportional balancing using the Harrison & Gibbards’s method.
