الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
HVAC systems in buildings must be complemented with a good control scheme to maintain conditions under any load variation. Efficient HVAC control is often the most cost effective option to improve the energy efficiency of a building. However, HVAC processes are characterized change on a seasonal basis so the effect of changing control strategy is usually difficult to predict.In this research, a framework for designing HVAC system is by using district cooling system (chillers, cooling tower and pumps) will be presented. A case study is carried out in MENA SMART LIFE (MSL) which is located in Dokki/Cairo, Egypt to calculate the cooling capacity and total energy. Then, Building Management System (BMS) will be used in the control of the HVAC system based on these values. The three energy management strategies are (the Occupied Strategy, the Optimum Start Strategy and the Occupied Economizer Strategy) will be illustrated. The first strategy (Occupied Strategy) saves energy by 30%. The second strategy (Optimum Start Strategy) saves energy by approximately 31%. The third strategy (Occupied Economizer Strategy) saves energy by approximately 37%. This thesis will show that using two strategies can save more energy. The best integration between strategies when the occupied economizer strategy is used with optimum start strategy (Occupied Economizer with Optimum Start Strategy), the energy saved can reach up to 38%. If the control system is not operating properly as designed, energy usage could be either greater or less than anticipated, and space conditions could be out of tolerance. However, it is more likely that poor control system performance will result in excess energy usage since problems which result in less energy consumption will likely generate complaints from occupants regarding comfort conditions. Two potential malfunctions in the combined system (Occupied Economizer with Optimum Start strategy) will be analyzed, and their effects on the energy consumption will be calculated. The first diagnosis (Chilled-water supply stays at constant design temperature) will increase the energy consumption 38%, while the second diagnosis (Mixed-air temperature is near outside-air temperature during cooling mode) will increase the energy consumption 11.6%.