Investigating the viability of air conditioning units in cooling buildings in Kampala.
Abstract
This research paper presents the results of ventilation studies in naturally ventilated residential or commercial buildings and those that use mechanical ventilation (air conditioning units) in Kampala city, Uganda. Interview surveys were used for obtaining the factors that influence the performance of air conditioning units as well as the costs incurred with their use. Some of the factors obtained were; the age of the air conditioning unit, the cooling load, the size of the room with the conditioner and the type of air conditioner employed. These factors were further investigated by obtaining data, this data enabled the performance of a regression analysis that showed the relationship between each of these factors and the output performance of the air conditioning unit employed in a building. The costs incurred with the use of air conditioning units included maintenance costs which comprised of activities such as cleaning of coils, refilling of refrigerants and repairs. Among the key costs incurred were electricity costs which varied depending on the type of conditioner considering different conditioners have a different power consumption rate. With the help of an infrared thermometer, the measurements of ambient temperatures for the air conditioned rooms and naturally ventilated rooms were obtained for ten buildings, in the morning, afternoon and in the evening. The air conditioned room temperature range was 190C to 230C while that of a naturally ventilated room was 220C to 280C. The findings obtained show that much as air conditioning units have a high economic cost, they are very effective in cooling buildings compared to natural ventilation, this is seen by the range of temperatures obtained. However, there are several factors that should be considered to ensure that the air conditioning unit is fully operational and effective in its purpose. If these are put into consideration by the building maintenance team, then the air conditioning unit is sure to last long while being efficient and effective. The researcher suggests further studies on air conditioning systems to be carried out to be able to find ways of navigating the electricity issues incurred with the use of air conditioning units in Kampala.