commercial HVAC system design, safe working practices and relevant standards, codes and regulations, including: design parameters for single-storey buildings (e.g. offices, restaurants, hotels and bars): customer and objective customer concept of environment desired economics client brief relevant design criteria: building purpose, location, orientation and shape external environment ambient conditions internal load diversity thermal capacity behaviour thermal load (full and partial) zoning and building usage: space and building occupancies, single purpose and multi-purpose system selection criteria: economics environment control requirements existing structures new structures system components space for equipment and system selection of appropriate system, equipment, ductwork and components systems and applications: design features, engineering and selection procedures for direct expansion air conditioning systems: air conditioning split systems and package units free blow and ducted fan coil units cooling, heat pump and electric heating air conditioning system components and piping selection air conditioning system components and piping selection, safe working practices and relevant standards, codes and regulations, including: relevant industry practices: AS/NZS 1677 Refrigerating systems SAA refrigeration code AS/NZS 3666 Air-handling and water systems of buildings ozone protection regulations ANSI/IIAR standards ANSI/ASHRAE mechanical refrigeration and IIAR bulletins and standards equipment manufacturer’s specifications and practices calculation of capacity in heat exchangers: Q = UA (LMTD) Q = mc∆t Q = m ∆h evaporators commercial types and applications coil bypass factor effects of evaporator TD on space humidity effects of air circulation on product conditions selection criteria and selection tables condensers: commercial types and applications effects of ambient conditions condenser control heat rejection factor condenser TD selection criteria and selection tables compressors types and applications capacity displacement volume flow rate theoretical capacity total volumetric efficiency effect of operating conditions, including suction pressure drop and superheating actual capacity power theoretical requirement effects of operating conditions actual requirements post defrost loads pull down torque requirements, high and medium and low back pressure compressors selection tables and motor selection liquid expansion devices: types, operation and applications effects from sub-cooling distributor types, operation and applications selection tables system load balance point encompassing: graphical representation line sizing and design velocity tables pressure drop in lines and fittings oil migration stabilisation refrigerant velocity effect of varying system capacity oil traps risers double risers liquid migration design for parallel components and multiplex systems automatic controls: fin spacing, suction temp to evaporator suction hot-gas bypass valves electronic control of valves and programmable logic controllers (PLC) refrigerant regulating valves solenoid valves condenser pressure regulating valves evaporator pressure regulating valves crankcase pressure regulating valves cycling controls pressure-stats thermostats defrost controls monitoring and alarm controls refrigeration automation systems control strategies control modes problem-solving techniques relevant job safety assessments or risk mitigation processes relevant WHS/OHS legislated requirements relevant workplace budget, quality, policies and procedures relevant workplace documentation. |