MODELLING THE CONDENSED WATER DISCHARGE RATE IN AN AIR CONDITIONAL SYSTEM

Abstract

In almost all modern buildings today, air-conditioning unit is used to provide a conditioned indoor environment while using large amounts of energy to cool, filter, and dehumidify the air in these structures. Condensed water from air-conditioning unit is formed from moisture in the air, it is high quality water that can be collected and used for different purposes. In Nigeria, the condensate are left to drain off on open grounds as waste. It is, therefore, necessary to develop a model that is capable of determining condensed water discharge rate in an air conditional system. An office located on the ground floor within the school of engineering and engineering technology building of the Federal University of Technology, Akure was used as case study. The dry bulb temperature and relative humidity of the office space were measured, using indoor/outdoor hygro-thermometer. The period for collection was between November 2015 to April 2016 and the air conditioning system works for a period of 8hrs per day. The result of six month data collected showed that a total of 528 L of condensed water was collected from a single 2500 W split type air conditioning unit used for the study. The highest condensate discharge rate of 1.07 L/hr was recorded on 6th and 7th April 2016. The data collected included; volume of condensate, dry bulb temperature, relative humidity, sensible heat ratio and dew point. These parameter were used in formulating the regression model. The coefficient of determination, R2, obtained for first, second and third order were 0.964, 0.9793, 0.9803, respectively. The model validation shows significant improvement in accuracy of the model in predicting the condensate of the experimental and predicted values. This study shows that condensed water from split type air conditioning unit has potential for water sustainability that should be pursued and, if this condensed water is properly channelled and harvested, its importance cannot be over emphasised.