ABSTRACT
In the Refrigerating Industry, the frosting of refrigerating coils and its effect on heat transfer is a problem of obvious importance. Amount of frost on the evaporator is dependent on the ambient temperature and air humidity. The performance of any cold storage unit depends upon maintaining storage space and evaporator temperatures within a range of most favourable conditions. This research project therefore is aimed at investigating the peculiarities of frosting, especially the variations of the heat transfer coefficient as a function of the duration of use during frosting with the influence of air conditions as close as possible to those in practice and to present some recommendations for defrosting on the basis of the results obtained. The theory of frost formation is outlined and its complexity identified. Design procedure of a cold storage is briefly given. This is to give readers an idea of how the various components of the system, eg, the evaporator, the condenser, etc were selected; the various factors that contributed to the successful working of the unit. Measurements on a house hold refrigerator are present tedj the results obtained are analysed and on the basis of these results and the experience obtained during the performed tests, some conclusions and recommendations are made.