Fresh fruits and vegetables are perishable products. Their final quality is influenced by several factors such as initial quality, harvest maturity, packaging, physical injuries and pulp temperature. Temperature plays the most important role in the preservation of fresh produce. Its effect is cumulative, hence affecting quality when produce is exposed to temperature variations even for short periods of time. In regions with extensive road networks, refrigerated semi-trailers are used to transport and distribute fresh fruits and vegetables. The semi-trailer is equipped with a refrigeration system to maintain the optimum transit environment of the produce. This paper presents an overview of refrigerated semi-trailers used in the transport of perishable horticultural products. The sources of heat loads inside a refrigerated semi-trailer are identified. A sample calculation of the heat load inside a refrigerated semi-trailer is presented using heat transfer equations. Recommendations on how to minimise the cooling requirements for the refrigeration system will also be made.