commercial refrigeration heat load estimating commercial refrigeration applications, safe working practices and relevant standards, codes and regulations, including: heat transfer: factors affecting heat transfer insulation material characteristics vapour barriers (seals) ambient conditions composite walls (heat flows) types of common insulation thermal conductivity film factors cabinet construction and design: deep freeze case meat case dairy case fruit and vegetable case drink cabinets air change load: room volumes room usage (average, medium and heavy) heat removed from cooling air to refrigerated conditions air curtains temperature differences door opening sizes Tamm’s equation product load: sensible heat latent heat heat of respiration storage temperatures unit running times humidity air flows stacking of products freeze, chill and thaw times total freezer/cool room loads: wall load air change load product load miscellaneous total load, safety factor and unit running times floor loads in cool rooms door opening loads (ASHRAE and RADS methods) door opening loads (for trucks) process cooling loads cooling chemical reactions energy balance methods sensible and latent cooling of gases sensible and latent cooling of water vapour in gas streams computer programs commercial air conditioning heat load estimating heat load estimating for commercial air conditioning applications, safe working practices and relevant standards, codes and regulations, including: heat flow in buildings: conduction convection radiation heat paths thermal storage different methods of calculations: ASHRAE carrier finite difference U values film coefficients solar heat: direct diffuse sol air temperature sun position calculations design conditions: outdoor monthly/daily corrections comfort/critical indoor effective temperature thermal comfort space characteristics equipment location zoning internal loads: lighting equipment people load profiles internal partitions fresh air/AS 1668 The use of ventilation and air conditioning in buildings calculation of fabric loads: walls roofs floors windows: glass types and factors shade factors internal and external shading shading from adjacent structures air quantity calculation: psychrometrics by-pass factor coil load variable air volume (VAV) air quantities piping and other losses refrigeration plant load computer software: responsible use relevant commercial refrigeration and air conditioning manufacturer specifications relevant job safety assessments or risk mitigation processes relevant WHS/OHS legislated requirements relevant workplace documentation relevant workplace policies and procedures. |