Refrigeration and air conditioning engineers provide an essential service to today’s way of living. Engineers install, maintain and service refrigeration and air conditioning equipment of varying sizes and types, mainly in commercial and industrial sites such as supermarkets, food processing factories, office blocks and computer centres. They need a knowledge of electrical components and systems, as air conditioning and refrigeration systems consist of many electrical and electronic components such as motors, thermostats, switches, pumps, fans and compressors.