Energy Management by Simulation of Air Handling Unit Degradation Behavior for Planning Maintenance Schedule

In this research, with the aim of effective cost reduction in the commercial building, focuses on maintenance activity of air handling units (AHUs) in water cooled water chiller (WCWC) cooling system, which costs approximately 50 to 60 percent of the electricity cost. This organization absolutely has a certain impact on cost of operation due to energy crisis. This makes the organization concerns about its cooling system´s energy consumption whether its utilization is running under waste or not. So management aims to cut down the unnecessary expenditure that is loss of energy cost in this study. Theoretically, taking good maintenance on system may cause less energy consumed. Thus it is important to seek the proper maintenance schedule by trading off between loss of energy cost and maintenance cost. To achieve that objective, understanding the degradation behavior of AHU is significantly meaningful for maintenance manager. Then simulation roadmap has been adopted and applied to this research. Data have been collected from AHUs on the first floor of this commercial building, during March to May, considered summer season in the south of Thailand. The result from this study found out that the optimal maintenance plan is to clean the filters and the cooling coils 54 times per year. It will decrease the total cost to 20 percent comparing to current maintenance plan, which is 28 times per year or every three month. However, other factors should be taken into consideration with this optimal plan such number of operators, rainy season in the south of Thailand, etc