The mathematical adjustment required to calculate actual refrigeration system performance at elevated locations where reduced atmospheric pressure and air density decrease cooling capacity and efficiency. At Johannesburg’s 1,750m elevation, refrigeration systems lose approximately 21% capacity compared to sea-level specifications, requiring systems to be oversized 25-30% to achieve equivalent performance. The altitude correction factor accounts for reduced air density affecting compressor volumetric efficiency, decreased condenser heat rejection capability, and lower atmospheric pressure impacting thermodynamic cycle performance. Most transport refrigeration equipment is rated at sea level (101.325 kPa), systematically misleading Gauteng operators about actual available capacity. Professional equipment specification requires applying altitude correction factors to manufacturer specifications rather than accepting sea-level ratings that guarantee underperformance in South African high-altitude operations.
Engineering Formula: For detailed calculations including worked examples with Johannesburg operational data, see Altitude Correction Factor for Refrigeration Capacity in our Technical Formulas Reference.
Related Terms: High-Altitude Refrigeration, Coefficient of Performance (COP), Transport Refrigeration Unit (TRU), Gauteng Frozen Delivery